Control of Emissions from Marine SI 

and Small SI Engines, Vessels, and 

Equipment 

Summary and Analysis of Comments 
Control of Emissions from Marine SI 

and Small SI Engines, Vessels, and 

Equipment 

Summary and Analysis of Comments 

Assessment and Standards Division 

Office of ransportation and Air Quality 

U.S. Environmental Protection Agency 

EPA420-R-08-016 

September 2008 
TABLE OF CONTENTS 

Index of Commenters 

1. General and Cross Program Issues 

2. Small SI Engines and Equipment 

3. Marine SI Engines and Vessels 

4. Evaporative Emissions 

 i 
INDEX OF COMMENTERS 

Commenter Abbreviation Docket ID Number 

EPA-HQ-OAR-2004-0008-

A. Swanson -0596 

AAR AAR -0669 

Alcock, G. -0601 

American Honda Motor Company, Inc Honda -0705 

-0767 

American Marine Sports -0639 

American Road & Transportation Builders 

Association 

ARTBA -0685 

American Society for Testing and Materials ASTM -0606 

Arctic Cat -0709 

Attwood Corporation -0653 

Baja Marine Corporation -0662 

Bombardier Recreational Products BRP -0674 

Briggs & Stratton -0657 

-0767 

Brunswick Commercial & Government Products, Inc. -0652 

Brunswick Corporation -0695 

California Air Resources Board California ARB -0682 

-0718 

Caterpillar Inc. -0813 

-0814 

-0822 

Challenger Powerboats, Inc -0644 

Chaparral Boats, Inc. -0630 

Cigarette Racing -0637 

Congresswoman Velazquez -0702 

Cummins Inc. -0719 

-0785 

-0795 

Delphi Corporation -0638 

Electro-Motive Diesel, Inc EMD -0687 

-0797 

-0801 

Emission Control System Engineering, Testing and 

Certification 

ECO -0712 

-0798 

-0802 

Engine Manufacturers Association EMA -0691 

-0768 

-0807 

-0808 

-0809 

-0810 

-0816 

-0817 

-0818 

ii 
Commenter Abbreviation Docket ID Number 

EPA-HQ-OAR-2004-0008-

Enviro-Fill, Inc. -0684 

-0806 

Environmental Control Corporation EVCC -0608 

-0654 

Environmental Defense -0648 

Euromot -0649 

-0766 

Exergy Partners Corporation -0627 

Fluoro-Seal International -0646 

Four Winns Boats L.L.C. -0650 

-0625 

General Electric Transportation GE -0679 

-0786 

General Motors GM -0787 

Godfrey Marine -0645 

Grady-White Boats, Inc. -0677 

Hallett Boats -0713 

Harold Haskew & Associates, Inc. -0640 

Holland, D. -0595 

Houston-Galveston Area Council H-GAC -0633 

Husky Corporation -0803 

Ilmor, Inc. -0658 

IMPCO Technologies, Inc. IMPCO -0614 

-0692 

-0812 

Inca Molded Products Inca -0700 

Indmar Products Indmar -0667 

Industrial Truck Association ITA -0800 

Ingenium -0616 

International Consortium for Fire Safety, Health and 

the Environment 

ICFSHE -0711 

ISMA ISMA -0671 

John Deere -0767 

Johnson County Environmental Department -0619 

Keichline, R. -0561 

Kelly, A. -0643 

Kohler Company -0703 

Larson/Glastron Boats -0626 

Leggett, N. -0603 

-0612 

Lowe Boats -0660 

Lund Boat Company -0655 

Maryland Department of the Environment -0722 

Massachusetts Marine Trades Association MMTA -0634 

MeadWestvaco -0723 

-0724 

MECA MECA -0668 

iii 
Commenter Abbreviation Docket ID Number 

EPA-HQ-OAR-2004-0008-

Mercury Marine Mercury -0693 

-0717 

-0716 

-0799 

Mid-American Regional Council Air Quality Forum MARC AQ Forum -0696 

Motorcycle Industry Council MIC -0701 

-0821 

National Association of Clean Air Agencies NACAA -0651 

NACCO Materials Handling -0714 

National Association of State Fire Marshals NASFM -0673 

National Marine Manufacturers Association NMMA -0688 

-0790 

-0792 

-0805 

Natural Resources Defense Council, et.al NRDC -0690 

Nautigaz -0727 

New Jersey Department of Environmental Quality NJ DEP -0710 

New York State Department of Environmental 

Conservation 

NY DEC -0659 

Nixon, T. -0599 

North American Sleekcraft, Inc. NAS -0666 

Northeast States for Coordinated Air Use 

Management 

NESCAUM -0641 

OPW Fueling Components -0804 

Outdoor Power Equipment Institute, Inc. OPEI -0675 

-0793 

Ozone Transport Commission OTC -0678 

Paddock, B. -0607 

Parker Hannifin Corporation -0672 

Pennsylvania Department of Environmental Protection PA DEP -0676 

Premier Marine, Inc. -0613 

Protectoseal -0615 

Pure Power EcoFuel LLC and Marine Propulsion 

Technology, Inc. 

Pure Power -0664 

Recreation Vehicle Industry Association RVIA -0647 

Regal Marine Industries, Inc. -0635 

Regulator Marine Inc. -0632 

Rolls Royce -0715 

S2 Yachts, Inc -0697 

Saint-Gobain, PPL -0661 

-0796 

Sea Ray Boats, Inc. -0683 

Shields Marine Hose -0624 

Skeeter Products, Inc -0706 

Small Engine Repair Service -0623 

Smith, F. -0694 

iv 
Commenter Abbreviation Docket ID Number 

EPA-HQ-OAR-2004-0008-

South Coast Air Quality Management District South Coast AQMD -0704 

-0689 

Sterling Performance Sterling -0665 

Stihl Inc. -0767 

-0784 

Suzuki Motor Corporation Suzuki -0698 

Trident Rubber, Inc. -0636 

Triton Boat Company -0656 

U.S. Coast Guard -0631 

Volvo Penta of the Americas Volvo -0708 

White, L. -0620 

Wisconsin Department of Natural Resources Wisconsin DNR -0725 

-0663 

Wood Mfg. (Ranger Boats) -0628 

Yamaha Motor Corporation USA Yamaha -0721 

-0826 

Yellowfin Yachts -0681 

v 

Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

1 Rulemaking Process and Cross-Program Issues 

What We Proposed: 

The comments in this section generally correspond to Sections I, II, VIII, IX, XI, XII, 

XIII, and XIV of the preamble to the proposed rule, where we give an overview of the 

rulemaking, describe the process for public participation, and detail a range of technical 

amendments that apply to programs other than those that are the focus of the proposed emission 

standards. The applicable regulatory provisions for cross-program issues are in 40 CFR parts 

1027, 1065, 1068, and 1074. In addition, we proposed technical amendments to specific 

programs in 40 CFR 89, 90, 91, 94, 1033, 1039, 1042, 1045, 1048, 1051, 1054. The Regulatory 

Impact Analysis describes the calculated air quality and benefits associated with the proposed 

standards in Chapters 2 and 8, respectively. 

1.1 General input 

1.1.1 Broad support and general observations 

What Commenters Said: 

EMA commented that it has been an active participant in the development of the NPRM 

for the next-phase Small SI engine standards. Specifically, EMA has worked to help EPA staff 

determine: (i) the most effective exhaust emission control technologies that could be applied to 

Small SI engines; (ii) the most effective evaporative emission control technologies that could be 

applied to Small SI engines and the equipment that they power; (iii) limitations on the 

applicability of such emission control technologies to Small SI engines and the equipment that 

these engines power; and (iv) the optimized timeline for deploying the available emission control 

technologies into the marketplace. The net result of that collaborative process is an NPRM that 

truly and properly reflects the maximum achievable emission reductions for Small SI engines 

and the equipment that they power. In that regard, EMA greatly appreciates the time and effort 

that have gone into the development of the pending rulemaking -- a rulemaking that has set forth 

extremely challenging and dramatic, but nonetheless potentially achievable, emission reduction 

targets. Indeed, the effort that has gone into this collaborative rulemaking has resulted in the 

promulgation of an overall framework of technology-forcing standards and accompanying 

regulations that are at the very limit of feasibility and implementability. As a consequence, that 

overall framework needs to be maintained in any final rule that results from the NPRM, since 

any potential increased stringency of the proposed standards or the overall regulatory program 

would necessarily result in an infeasible and nonimplementable rule. 

EMA continued to comment that the NPRM properly recognizes the inherent constraints 

on the transfer of advanced exhaust emission control systems to Small SI engines, and 

appropriately limits the efficiency of the required aftertreatment to achieve the proposed 

standards to those levels that can be effectively implemented taking into consideration, among 

other things, noise and safety. Similarly, the NPRM properly recognizes that evaporative 

emission control of Small SI engines and the equipment these engines power may involve the 

1-1 
Chapter 1: Rulemaking Process and Cross-Program Issues 

engine manufacturer, the equipment manufacturer, or the component supplier. Accordingly, 

EMA supports the overall framework of the NPRM, and urges EPA to finalize a rule that 

preserves that framework in order to maintain the feasibility of the pending rulemaking. 

EMA generally supports the NPRM’s approach to the certification process and the 

standardization of testing requirements. Certification is critical to the creation of a level playing 

field. Manufacturers must have confidence that all competitors are required to meet the same 

requirements, and are subject to the same liabilities with respect to emission related product 

performance and warranty. Approved alternate test procedures must be available for all 

manufacturers without subsequent approval. EMA recommends that approved alternative 

procedures for emission testing, both exhaust and evaporative, and exhaust emission 

deterioration factor determination be documented and posted on the EPA website for all 

manufacturers to see and use. In addition, EMA has the following specific concerns with respect 

to the NPRM’s proposed certification and testing requirements that should be resolved in the 

final rule. (see section 1054.245(b)(9)). 

EMA commented on §1065.12 “Approval of alternate procedures.” that approved 

alternate test procedures must be available for all manufacturers without subsequent approval. 

EMA recommends that approved alternative procedures be documented and posted on the EPA 

website for all manufacturers to see and use. 

Kohler Co. is committed to participating with government and regulatory agencies in the 

development of responsible environmental law and regulations. Kohler believes in harmonizing, 

to the greatest extent possible, the EPA Phase 3 regulation with the California Tier III regulation. 

A 50-state regulation is in the best interest of the industry and the Phase 3 regulation reasonably 

balances the benefit to the environment with the additional product costs of compliance. Kohler 

believes the resulting compliant product will perform satisfactorily in every way, including 

safety. Kohler agrees with the overall framework of the NPRM for Phase 3 regulations and has 

participated in and publicly supported EPA’s efforts in developing the Phase 3 regulation. 

However, Kohler has some concerns with the details of the regulation. There are a few aspects of 

the regulation on which Kohler feels compelled to provide additional comment. These include: 

determining engine displacement for the LSI exemption, exhaust emission calculations, 

transparency of approved alternative emission test cycles, allowable maintenance for DF testing, 

and record keeping/reporting. 

NMMA commented that its members are supportive of EPA’s proposal to control 

evaporative and exhaust emissions from marine SI engine s and fuel system components. 

NMMA members are committed to producing environmentally responsible products. Over the 

years, the recreational marine industry has devoted significant time and resources to ensure that 

they are in compliance with all applicable federal environmental and safety regulations as well as 

recommended industry “best practices” and standards. NMMA also has worked closely with 

EPA on the implementation of several important regulatory programs, including this current 

proposal. With all of these rulemakings, NMMA has appreciated EPA’s willingness to consider 

additional information and data from NMMA members and work collaboratively with the 

recreational marine industry to address concerns which the industry has had with the specifics in 

these rulemakings. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Indmar commented that they support the proposed federal emission regulations for new 

marine spark-ignited sterndrive/inboard engines that will substantially reduce emissions from 

these engines. There are a few areas that they would suggest alternative language or changes. 

Indmar Products supports the enactment of the proposed Federal sterndrive/inboard exhaust 

emissions standards with the noted changes. 

Overall, BRP commented that they are supportive of EPA’s proposal to control 

evaporative and exhaust emissions from marine SI engines and fuel system components and to 

the revisions of the regulations impacting off-road recreational vehicles and engines. Over the 

years, BRP has devoted significant time and resources to ensure compliance with all applicable 

federal environmental and safety regulations as well as recommended industry “best practices” 

and standards. BRP also has worked closely with EPA on the implementation of several 

important regulatory programs, including this current proposal. With all of these rulemakings, 

they have appreciated EPA’s willingness to consider additional information and data. 

Mercury Marine supports EPA’s proposal to control evaporative and exhaust emissions 

from marine SI engines and fuel system components. They are committed to producing 

environmentally responsible products. Over the years, the recreational marine industry has 

devoted significant time and resources to ensure that they are in compliance with all applicable 

federal environmental and safety regulations as well as recommended industry “best practices” 

and standards. Mercury Marine has worked closely with EPA on the implementation of several 

important regulatory programs, including this current proposal. 

Mercury Marine has a few remaining concerns regarding the technology, timing, and 

implementation required by the proposal. Catalysts and low permeation hoses are available and 

can be incorporated into marine exhaust and fuel systems. However, there are market issues, 

some that are out of their control, that have an impact on our abilities to meet some of the 

proposed standards in the proposed timeline. Therefore, they will propose alternatives to the 

items they have issues on that will provide EPA with emissions reductions but maintain their 

business, customers, and employees. If the issues they have raised in these comments are 

adequately addressed, then Mercury Marine fully supports this rule. 

Yamaha is supportive of EPA’s proposal with the addition of NMMA industry comments 

to control evaporative and exhaust emissions from Marine SI engines and fuel systems 

components. Over the past many years Yamaha has worked closely with the EPA on other 

rulemakings for motorsports products on both evaporative and exhaust emission controls. With 

all these rulemakings Yamaha has appreciated EPA’s willingness to consider additional 

information and data from Yamaha and work with the industry to address concerns and issues 

relative to specifics in these rulemakings. It is Yamaha’s position that although this proposal is 

very comprehensive and they are in general agreement with its intent, however there are still a 

few remaining concerns outstanding that need to be addressed regarding technology availability 

and implementation timing of this proposal. As they hope, these comments along with those 

submitted with their approval of the NMMA will demonstrate the need for additional lead time 

to design, manufacture and implement effective controls for exhaust and evaporative emissions. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

Yamaha also will offer comments on other aspects of the proposal in regards to certification, 

ABT and compliance test protocols. 

Volvo Penta commented that “care for the environment” is a core corporate value of the 

entire Volvo Group, including Volvo Penta. Volvo Penta supports EPA’s proposal to control 

exhaust emissions from SD/I engines, and has been committed to producing environmentally 

responsible products. Over the years, Volvo Penta has devoted significant time and resources to 

ensure their products comply with all applicable federal environmental and safety regulations as 

well as recommended industry standards. During the past several years, Volvo Penta has worked 

closely with the National Marine Manufacturers Association (NMMA) and the EPA to craft a 

workable solution to emissions concerns. Throughout this process, Volvo Penta has appreciated 

EPA’s willingness to consider additional information and data from the industry. These 

collaborative efforts have reduced industry concerns regarding the proposed rule. The comments 

included reflect the Volvo Penta's few remaining issues of concern: 

Euromot commented that they have reviewed the proposed Phase 3 regulation within 

their membership and they fully support the OPEl comments. As established manufacturers with 

a long compliance history they understand the new concept of EPA for imports (and exports). 

The changes proposed by the OPEI comments are essential for the Euromot members to be 

present on the market in the future. Without these changes the regulation would be not practical 

and a dramatic burden (financial and administrative) would be laid to the industry. 

In a public hearing, Ilmor stated that broadly speaking, Ilmor supports the proposed EPA 

Rule. 

Pleasurecraft Marine commented in a hearing that their company is fully supportive of 

emission reductions and is working diligently to solve the many complex technical and 

implementation issues associated with manufacturing a catalyst controlled engine. They would 

like to thank the EPA for their insights in crafting a document that, with minor changes, will be 

of great benefit to our industry, the boating community and the environment. 

Brunswick supports EPA's efforts of improving the environment through cleaner 

products. 

Inca does support the need for control of evaporative emissions through low permeation 

fuel tanks, diurnal emission controls, and low permeation hose. However, due to the direct 

correlation their products have with boating safety they want to be sure that the requirements of 

this standard do not create a low emission product that is inferior in quality to the current product 

that has been successful in the marine industry for years. 

Heraeus commented that their small engine solutions provide a variety of different 

catalyst solutions. They provide effective conversion of the bad stuff coming out of the engine. 

They have catalysts which match the durability needed, in other words, addressing the DF factor 

for the engine application. And an engine exhaust catalyst is really quite a cost-effective 

approach. They support the proposed EPA Phase 3 emissions regulations for Class I and Class II 

1-4 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

nonroad spark-ignition engines. Heraeus is ready and believes this rule should be finalized as 

soon as possible. 

MeadWestvaco Corporation supports the EPA’s proposal to control evaporative 

emissions from marine SI engines and fuel system components and is committed to providing 

products used to control these emissions. 

NACAA strongly supports prompt EPA action to reduce emissions from these sources. 

They believe this long-awaited proposal – which includes HC, NOx, and carbon monoxide (CO) 

exhaust emission standards, as well as evaporative emission standards – is a critically important 

step forward. 

EVCC commented that as their technology has proven reductions in HC+NOx of up to 

98.9% on a two-stroke engine and 90% on a four-stroke engine (while also significantly reducing 

CO), they are not only in full support of the current regulations, but they encourage our 

organizations to set even more stringent standards in the near future. 

Ozone Transport Commission (OTC) and Maryland support the EPA’s effort to regulate 

emissions from nonroad spark-ignition engines, vessels, and equipment. OTC has anticipated 

the EPA’s proposed regulation. In a March 14, 2006 letter to the EPA Administrator several 

Midwest and OTC states urged the EPA to promulgate the regulations for nonroad spark-ignition 

engines. As the letter stated, this source category “has the potential to provide very significant 

reductions.” Additionally, the OTC adopted Resolution 06-02 on June 7, 2006 requesting that 

EPA develop and implement a strong national program reflecting current technology 

advancements regarding small engine emissions. The OTC is encouraged by the May 18, 2007 

proposal. 

NESCAUM (Northeast States for Coordinated Air Use Management) submitted 

comments on EPA’s Proposed Rule for Control of Emissions from Nonroad Spark-Ignition (SI) 

Engines and Equipment commending EPA and strongly supporting the goals of this rulemaking 

effort. NESCAUM is an association of state air pollution control agencies in Connecticut, Maine, 

Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, and Vermont. 

The Mid-America Regional Council (MARC) Air Quality Forum, created in accordance 

with Section 174 of the Clean Air Act to coordinate the development and implementation of air 

quality policy in the bi-state Kansas City region, wishes to express its strong support for EPA’s 

proposal to set federal emissions standards for small spark-ignition engines. The public health 

impacts of ground-level ozone and fine particulates are well documented, and to the extent that 

the proposed rule will lead to significant and measurable reductions in both pollutants nationally, 

they urge EPA to implement the small engine rule as expeditiously as possible. 

The California Air Resources Board (California ARB) commented that the federal Clean 

Air Act (CAA) Amendments of 1990 preempt California from controlling emissions from new 

farm and construction equipment under 175 horsepower (hp). Because of this preemption, 

significant emissions from these engines are beyond California ARB’s authority to regulate, and 

California ARB must rely on EPA to establish regulations. Furthermore, it is important that EPA 

1-5 
Chapter 1: Rulemaking Process and Cross-Program Issues 

also adopt more stringent emission standards for nonpreempted engines, such as those used in 

marine applications. Federally certified engines used in marine vessels can be used in California 

which could impact California’s ability to meet clean air goals. Adoption of the proposed 

regulation outlined in the proposed rule by EPA is necessary for the protection of public health in 

California and to comply with air quality standards. New stringent and cost effective standards 

should be adopted for these categories in a timely manner to ensure that the cleanest engines and 

equipment be introduced into the fleet at the earliest possible date. In general, California ARB 

supports the direction that EPA is taking to control emissions from nonroad spark-ignition 

engines and equipment included in this notice of proposed rulemaking (NPRM). 

The South Coast Air Quality Management District (SCAQMD) staff appreciates this 

opportunity to provide formal comments on the proposed regulation for Nonroad Spark- Ignition 

Engines and Equipment. Although they commend the EPA’s efforts in developing this proposal, 

the SCAQMD staff believes that the proposed regulations must be further strengthened in order 

for California and in particular, the South Coast Air Basin, to meet applicable federal fine 

particulate matter (PM2.5) and 8-hour ozone air quality standards in an expeditious manner. 

The NJDEP supports the adoption of federal emission standards, which are consistent 

with standards adopted by California ARB. With respect to the implementation dates, the NJDEP 

encourages expeditious implementation of the federal standards and requests that the 

implementation dates be advanced to align more closely with the implementation dates 

established by California ARB. 

Wisconsin DNR commends EPA for its leadership in issuing this proposed rule and 

seeking comments on the merits of better emission standards. They support EPA’s proposal to 

set stringent emission standards for new nonroad spark-ignition engines, equipment, and vessels. 

Emissions from the engines covered by this proposal are substantial that contribute to 

unhealthful concentrations of PM, ozone, CO, and toxic air pollutants, which translate into 

serious adverse health impacts. The proposal would significantly reduce harmful exhaust 

emissions as well as evaporative emissions from these sources – which include HC, NOx, and 

CO. 

New York State DEC supports EPA’s proposal to set stringent emission standards for 

new nonroad spark-ignition engines, equipment, and vessels. Emissions from the engines 

covered by this proposal are substantial that contribute to unhealthful concentrations of PM, 

ozone, CO, and toxic air pollutants, which translate into serious adverse health impacts. The 

proposal would significantly reduce harmful exhaust emissions as well as evaporative emissions 

from these sources – which include HC, NOx, and CO. 

New York State DEC continued to comment that the importance of reducing emissions 

from small spark-ignition engines used in applications such as lawn and garden equipment, and 

recreational marine emissions, cannot be overstated. Most of the operation of these engines 

occurs during warm weather conducive to the formation of ground level ozone, and their ozone 

precursor emissions are poorly controlled compared to other classes of engines and vehicles. 

Even with the proposed standards, an hour of operation of these engines will yield hydrocarbon 

and oxides of nitrogen emissions comparable to driving an average (Tier 2 Bin 5) new light duty 

1-6 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

vehicle hundreds, in some cases thousands, of miles. Indeed, it is likely that many households 

produce more ozone-forming emissions maintaining their lawn than commuting to work. 

Considering the comparatively high emissions levels of these engines, and their increasing 

importance to emission inventories, we believe that additional future reductions are necessary. 

The Department urges EPA to continue its efforts to identify emissions control technology that 

achieves emission reductions beyond what is currently proposed. 

New York State DEC continued to comment that although the standards proposed by 

EPA provide significant and necessary reductions in ozone forming emissions from small land 

based engines and recreational marine engines, these engines will still be relatively poorly 

controlled compared to other mobile sources. These engines will still emit ozone precursors out 

of proportion to their numbers and hours of operation. The disproportionate emissions levels of 

these engines compared to passenger vehicles shows that there is a need for more stringent 

standards than the ones currently proposed. EPA research into nonroad spark-ignition engine 

emissions control is crucial to identifying available technology which can achieve a greater 

degree of emissions reductions. In particular additional work is needed to facilitate the 

application of catalysts to outboard and personal watercraft engines, many of which are 

automotive sized. They urge EPA to continue its efforts in this field, and build on its current 

success, ultimately promulgating more stringent regulations for all of these classes of nonroad 

engines. 

Pennsylvania DEP strongly supports EPA’s action, but offers additional 

recommendations to strengthen the final regulation. While DEP strongly supports EPA’s 

proposed action to reduce emissions from small land-based and marine spark-ignition engines, 

equipment, and vessels, and urges EPA to promulgate the final rule as soon as practicable, DEP 

understands and acknowledges that certain aspects of the proposed rulemaking were delayed by 

further study mandated by law and that Congress has also expressly precluded states from taking 

any action more stringent than EPA’s on small spark-ignition engines. Therefore, DEP urges 

EPA to ensure that the final rule is fully implemented expeditiously to achieve the greatest 

degree of emission reductions. 

The Houston-Galveston Area Council (H-GAC) Board of Directors would like to offer 

general support and comments for the Environmental Protection Agency proposed rule. They 

greatly appreciate the efforts of the EPA to draft this proposed rule, which targets several of 

these mobile sources for significant emission reductions that could not otherwise be achieved. 

Johnson County, Kansas commented that they are in full support of the proposed 

regulations on nonroad motor engines. In an effort to lower harmful ozone causing emissions 

such as those spewed from lawn equipment, they find the proposed standard to be an effective 

step in improving the health of our social and biotic communities. 

Clean Air Watch commented that smog is a serious public health problem: technically 

known as ozone, smog can cause asthma attacks among children and adults, send people to 

hospital emergency rooms, and reduce a person's lung capacity. It has even been linked to 

premature death. The evidence is quite clear that even though we have reduced air pollution 

through other Clean Air Act standards, such as those for motor vehicles, we still need to make 

1-7 
Chapter 1: Rulemaking Process and Cross-Program Issues 

further progress to protect breathers. Just last Saturday, the Washington Post reported on 

continuing air pollution problems in the Washington, D.C. area. And our Clean Air Watch 

surveys verify that similar problems persist in many states. Clean Air Watch continued that 

EPA's independent science advisers and the agency's own scientists have concluded that existing 

air quality standards for smog must be made stricter to protect kids with asthma and others. As 

we clean up cars and trucks, small engines are an increasingly large part of the pollution 

problem. Cleaning them up absolutely must be part of the solution. EPA’s proposed standards 

are a good step in the right direction. Clean Air Watch commented that it would be better for air 

quality if they could take effect sooner. They hope we will resist any effort to delay or weaken 

these standards. They believe EPA's detailed studies have put to rest concerns previously raised 

about safety. So they encourage EPA to move forward and issue these standards in final form 

this year. 

 Environmental Defense strongly supports the immediate issuance of a final rule to control 

air pollution from spark-ignition marine and small engines in light of the serious public health 

and welfare problems posed by the exhaust and evaporative emissions from these engines. They 

believe a final rule that reflects, or is more protective than, the timing and level of reductions 

currently required by California ARB is achievable, cost-effective and necessary to protect 

human health and the environment. 

N. Leggett offered support of the concept of requiring pollution control technology for 

spark-ignited engines. However, some fine tuning of the proposed regulations is needed to 

prevent the regulations from inhibiting progress in the invention of new technology and the 

training of technologists. 

R. Keichline is supportive of the new legislation to reduce air emissions. 

A. Swanson commented on a recent EPA air emissions proposal (Docket ID No. EPAHQ-OAR-2004-0008). The commenter supported the proposal to: a) increase exhaust emission 

standards for marine spark-ignition engines and small land-based nonroad engines, b) establish 

new evaporative emission standards for equipment and vessels using these engines. This 

proposal is reasonable, for these standards would apply only to newly manufactured products, 

and it would reduce the harmful health effects of ozone and carbon monoxide from these 

engines, equipment, and vessels if implemented. Thank you for the opportunity to comment, and 

the commenter hopes that these reasonable regulations will be finalized and implemented in a 

timely manner. 

T. Nixon commented in full support of this, and only wishes it could be implemented 

sooner. Much small-engine equipment is not needed for businesses or vital household needs, 

they are luxury goods that contribute to sound and air pollution in recreational and residential 

areas. The commenter believes that reducing emissions from watercraft will help make boating 

more pleasant and enjoyable, and these regulations should certainly help clear the air for people 

in dense urban areas. If higher costs do reduce sales, it may further serve to increase the health 

of the nation by having people use push-mowers instead of ride-on mowers, and rakes instead of 

leaf-blowers. Although, admittedly, increased use of snow shovels (vs. snow blowers) could 

1-8 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

actually reduce health, as that can be back-breaking work. Good luck getting these new 

emissions regulations (or some version of them) implemented. 

B. Paddock commented that the regulatory analysis persuades the commenter that there 

are substantial benefits to the human environment to be obtained by adoption of the proposed 

rules on small engine emissions. The commenter urges EPA to advance the effective date and 

deadline for implementation of the regulations. These improved products can be built with 

existing knowledge and technologies as is evident from products sold in California. Low 

emission mowers and other products should be made available throughout the U.S. at the earliest 

possible date. The years of delay in the implementation of rule are unnecessary. As a consumer, 

the commenter wants to buy emissions reduced products now. The cost of gasoline means the 

commenter will recover the costs of fuel efficiency (and reduced emissions) in a shorter time. 

Lawn mowing is becoming unaffordable. Coupled with drought and native plant landscaping, 

the mower industry is likely in for slow period. New, fuel efficient, "greener" low emission 

mowers offer a reason to buy sooner rather than wait for years for a better product. The same is 

true for boat motors. The manufacturer who first makes rule compliant products available will 

see a surge of sales. 

Nautigaz commented in their first e-mail that it was for them very good news, it is it for 

several reasons. Of course they hope to be able to work now, thanks to these new standards, but 

they also hope to bring a solution which goes in the "direction of the History." If all is not 

perfect in the USA, they reassure in France it is exactly similar! It is perhaps why our countries 

are friendly since the Lafayette General. 

The Environmental Club of Colorado State University – Pueblo commented that they are 

overwhelming glad to see that new regulations are going to be implemented restricting air 

pollutants from lawn mowers and small boat engines. They are very glad that these new 

regulations are coming to pass. However, they believe that the dates which these regulations will 

go into effect are too far out. They believe it is more than possible to lessen the period of time 

until these regulations take effect. Please consider enacting these regulations much sooner, as our 

Earth desperately needs clean air as do we all. 

1-9 
Chapter 1: Rulemaking Process and Cross-Program Issues 

Letters: 

Commenter Document # 

NMMA 0688 

EMA 0691 

N. Leggett 0603 

Johnson County, Kansas 0619 

OTC 0678 

South Coast AQMD 0704 

Maryland 0722 

NJ DEP 0710 

R. Keichline 0561 

A. Swanson 0596 

T. Nixon 0599 

B. Paddock 0607 

Wisconsin DNR 0663 

New York State DEC 0659 

Nautigaz 0727 

Houston-Galveston Area Council 0633 

NESCAUM 0641 

Environmental Defense 0648 

NACAA 0651 

Indmar 0667 

Bombardier 0674 

MeadWestvaco 0723/0724 

Volvo Penta 0708 

Yamaha 0721 

Mercury 0693 

The Mid-America Regional Council (MARC) Air Quality Forum 0696 

California ARB 0682 

Pennsylvania DEP 0676 

Kohler 0703 

EVCC 0608 

Ilmor (hearing) 0642 

Pleasurecraft Marine (hearing) 0642 

Brunswick 0695 

Clean Air Watch (hearing) 0642 

Heraeus (hearing) 0642 

Inca Molded Products 0700 

Environmental Club of Colorado State University – Pueblo 0730 

Euromot 0649 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

We appreciate all comments on the proposed rule; specific responses to the various concerns 

raised by individual commenters are in the rest of this Summary and Analysis of Comments 

document. 

1.1.2 Legal authority 

What Commenters Said: 

NACAA commented that emission control requirements for small nonroad spark-ignition 

and marine spark-ignition engines and equipment should achieve the greatest reductions feasible 

as soon as possible. In Section 101(a)(3) of the Clean Air Act, Congress vests state and local 

clean air agencies with “primary responsibility” for the control of air pollution. This is a 

responsibility they take very seriously. As NACAA seeks to achieve and sustain clean, healthful 

air throughout the country, they must consider the full measure of emission reductions feasible 

from every source of pollution as quickly as possible. With respect to nonroad spark-ignition 

engines smaller than 50 horsepower, however, states and localities other than California, very 

unfortunately, are preempted from adopting standards or other requirements. Therefore, it is 

incumbent upon EPA to ensure that this rule achieves the greatest degree of reductions possible 

as soon as possible. 

Environmental Defense commented that Congress is concerned about the air pollution 

caused by nonroad mobile sources such as the spark ignition marine and small engines subject to 

this rule, they enacted § 213 as part of the Clean Air Act amendments of 1990. See Pub. L. No. 

101-549 § 222, 104 Stat. 2399, 2500-02 (1990) (codified at 42 U.S.C. § 7547). Section 213 

instructs EPA to set emission standards for nonroad engines that reflect the “greatest degree of 

emission reduction achievable”. 42 U.S.C. § 7547(a)(3). For this reason, the D.C. Circuit 

consistently has held these provisions of the CAA to be “technology-forcing.” Husquvarna AB v. 

EPA, 254 F. 3d 195, 200 (D.C. Cir. 2001) (upholding EPA decision to give priority to goal of 

reducing emissions, over cost, noise, energy and safety factors in setting Phase 2 emission 

standards for handheld small engines); see also NRDC v. EPA, 655 F.3d 318, 328 (D.C. Cir. 

1981) (stating that the legislative history of the CAA demonstrates that Congress intended EPA 

to “press for development and application of improved technology rather than be limited by that 

which exists today.”) Importantly, Section 213 also directs EPA to set emission standards that: 

shall take effect at the earliest possible date considering the lead time necessary to permit the 

development and application of the requisite technology, giving appropriate consideration to the 

cost of compliance within such period and energy and safety. 42 U.S.C. § 7547(b). Whether a 

particular standard satisfies both statutory prongs of Section 213, therefore, involves a question 

of stringency as well as timeliness. See e.g. Bluewater Network v. EPA, 370 F.3d 1, 21-22 (D.C. 

Cir. 2004). Clearly, if EPA were to set standards reflecting the “greatest degree of emission 

reduction achievable” based on technology available in 2007, but not implement such standards 

until much later, the actual emission reductions resulting from such rules would be minimal, at 

best. Such standards, even though technology-forcing in 2007, would likely lag behind the 

technological advances made in the interim years between the initial proposal and the ultimate 

implementation date. Consistent with the statutory mandate to implement emission standards “at 

1-11 
Chapter 1: Rulemaking Process and Cross-Program Issues 

the earliest possible date”, EPA must “provide a reasonable explanation of the specific analysis 

and evidence upon which the Agency relied.” Id. at 21. Anything short of this fails the arbitrary 

and capricious test applied to EPA rulemaking under the CAA and APA. See Motor Vehicle 

Mfrs. Assn. v. State Farm Mut., 463 U.S. 29, 52 (1983). 

Letters: 

Commenter Document # 

Environmental Defense 0648 

NACAA 0651 

Our Response: 

 We understand these comments to be generally reinforcing the statutory provisions upon 

which we based our proposed rule. See the preamble to the final rule and the rest of this 

document for a description of specific issues related to the timing and feasibility of implementing 

standards that we believe represent the greatest degree of emission reductions that are achievable 

at this time. 

1.1.3 Process concerns 

What Commenters Said: 

Environmental Defense commented that most importantly, they believe EPA must act 

expeditiously in publishing and implementing final rules for these SI engines. Indeed, they 

believe EPA has already acted unlawfully and in violation of its statutory duties under the Clean 

Air Act (CAA) and other laws due to the amount of time that has passed since Congress required 

the Agency to reduce emissions from these engines. 

Houston-Galveston Area Council (H-GAC) commented that due consideration should be 

given to the economic impacts of this rule, particularly on small businesses; however, H-GAC 

believes that these concerns should not outweigh the more primary concerns of protecting the 

public health and achieving Clean Air Act compliance. They therefore encourage the EPA to 

finalize these emission standards before the end of this year at the most stringent levels that are 

technically feasible to achieve the maximum environmental benefit. H-GAC encourages the EPA 

to implement the standards as quickly as it is possible to do so, but no later than 2009. This 

would provide the maximum benefit to their region’s air quality improvement efforts. 

EMD urges EPA not to do what it has done here – to include in a proposed rule items that 

are unconnected, or only peripherally connected, to the subject of the rulemaking. The current 

proposal includes new proposed rules on certification fees and on preemption provisions that are 

only marginally connected to the spark-ignition engines and equipment that are the main subject 

of the proposal. The included items are not even listed in the title of the rule proposal. EPA’s 

practice here makes life difficult and increases expense for regulated parties. All manufacturers 

must read carefully every EPA proposed rule, including those seemingly unrelated to their 

products, to make sure that EPA has not piggybacked provisions important to their markets on 

them. EPA should make proposals such as the certification fees rule and the preemption rule the 

1-12 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

subjects of separate rulemakings, with their own entries in the Federal Register. There is 

precedent for such an action; for example, the original rule proposal extending certification fees 

to nonroad engines 17 stood alone, and was not piggybacked on another rule proposal. 

ASTM commented that the following standards referenced have been updated: D 471-98 

is now D 471-06; D 323--99a is now D 323-06; E29-93a is now E29-06b. If EPa would like 

copies of the updated standards, they would be happy to send them. 

Letters: 

Commenter Document # 

EMD 0687 

ASTM 0606 

Houston-Galveston Area Council 0633 

Environmental Defense 0648 

Our Response: 

The comments from Environmental Defense summarize the position they took in 

litigation regarding the applicability of the original statutory deadline for completing this 

rulemaking. The district court decision upheld EPA’s position that the original deadlines no 

longer applied once Congress adopted a separate requirement to publish a safety study related to 

the safety implications of new emission standards before proposing such standards (in the docket 

under EPA-HQ-OAR-2004-0008-0840). Environmental Defense has appealed this decision. We 

continue to believe that we have not acted unlawfully in completing this rulemaking. While we 

have worked diligently to complete the rulemaking as quickly as possible, addressing a wide 

range of technical issues required substantial time and interaction with many interested parties. 

We believe the result of all of these efforts is a rule that is thorough and effective in achieving 

our objectives. 

We share the perspective of the Houston-Galveston Area Council that the rule should 

achieve emission reductions to protect public health and meet our statutory obligations while 

taking into account the particular concerns for small businesses that must meet new 

requirements. We believe the final rule achieves this balance by including far-reaching emission 

standards in combination with a variety of provisions to address concerns related to compliance 

burdens for small businesses. The timing of the final rule is somewhat behind the schedule 

envisioned at the time of the proposal, but we are able to preserve the most important portions of 

the implementation schedule described in the proposed rule. 

We understand the concerns raised by EMD, however we do not believe they are 

sufficient to justify excluding the issues from this rulemaking. The inclusion of such broad 

issues is this rulemaking is appropriate, especially under the new “plain-language” regulatory 

construct, which allows the use of common procedures across multiple categories. All changes 

to these common regulations are made through public rulemakings such as this. In addition, we 

made great efforts to reach out to all affected stakeholders in such rulemakings. 

1-13 
Chapter 1: Rulemaking Process and Cross-Program Issues 

ASTM has further updated its standards beyond the changes described in its comments 

on the proposed rule. We have included the latest ASTM standards for every reference and 

appreciate ASTM’s eager cooperation in supporting this effort. 

1.1.4 Commenters referencing other commenters 

What Commenters Said: 

Euromot reviewed the proposed Phase 3 regulation within their membership and they 

fully support the OPEl comments. As established manufacturers with a long compliance history 

Euromat understands the new concept of EPA for imports (and exports). The changes proposed 

by the OPEI comments are essential for the Euromot members to be present on the market in the 

future. Without these changes the regulation would be not practical and a dramatic burden 

(financial and administrative) would be laid to the industry. 

Honda commented that they are a member of the Engine Manufacturers Association 

(EMA), Outdoor Power Equipment Institute (OPEI), and the National Marine Manufacturers 

Association (NMMA) and supports the comments submitted by each of these trade associations. 

Kohler is a member of the Engine Manufacturer Association (EMA) and the Outdoor 

Power Equipment Institute (OPEl) and as such supports the written comments being submitted 

by them. 

Arctic Cat is in full support of comments from MIC and ISMA and have no intention of 

diminishing the importance of additional issues raised by either association by not including 

specific comments here. 

BRP supports the comments submitted by the National Marine Manufacturer's 

Association (NMMA), International Snowmobile Manufacturer's Association (ISMA), and the 

Motorcycle Industry Council (MIC). In addition, BRP has individual comments on certain 

aspects of this regulation which could not be addressed through these organizations. Detailed is a 

summary of these comments along with additional information to support the NMMA, ISMA, 

and MIC comments. 

Yamaha is supportive of EPA’s proposal with the addition of NMMA industry comments 

to control evaporative and exhaust emissions from Marine SI engines and fuel systems 

components. As they hope, these comments along with those submitted with their approval of 

NMMA will demonstrate the need for additional lead time to design, manufacture and implement 

effective controls for exhaust and evaporative emissions. 

EMD has read, agrees with, and supports the comments to be submitted by the 

Association of American Railroads. They urge EPA to act in accordance with those comments. 

Heraeus is very supportive and a member of OPEI Fuel and Exhaust Clean Air Act 

Committee. Heraeus is also a member of MECA with membership and workshop participation. 

1-14 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

OTC and Maryland commented in finalizing this rule. OTC advises EPA to examine 

closely the recommendations made by the Northeast States for Coordinated Air Use 

Management (NESCAUM) and the National Association of Clean Air Agencies (NACAA). The 

recommendations made by these organizations will improve upon EPA’s proposal and offer 

states much needed reduction in ozone forming precursors. 

The Mid-America Regional Council (MARC) Air Quality Forum, created in accordance 

with Section 174 of the Clean Air Act to coordinate the development and implementation of air 

quality policy in the bi-state Kansas City region, wishes to express its strong support for the EPA 

proposal to set federal emissions standards for small spark-ignition engines. MARC also shares 

some concerns raised by the National Association of Clean Air Agencies (NACAA) in its June 5, 

2007, testimony to EPA. 

The NJDEP supports the comments submitted by the National Association of Clean Air 

Agencies (NACAA) and the Northeast States for Coordinated Air Use Management 

(NESCAUM) for the proposed rule. 

Pennsylvania DEP concurs in the technical recommendations made by the National 

Association of Clean Air Agencies (NACAA). 

The comment from the Natural Resources Defense Council related to federal preemption 

of state regulation was co-signed by representatives of Environmental Defense, Friends of the 

Earth, and Coalition for Clean Air. 

Letters: 

Commenter Document # 

EMD 0687 

Arctic Cat 0709 

OTC 0678 

Maryland 0722 

NJ DEP 0710 

NRDC 0690 

Bombardier 0674 

Yamaha 0721 

The Mid-America Regional Council (MARC) Air Quality Forum 0696 

Honda 0705 

Euromot 0649 

Pennsylvania DEP 0676 

Kohler 0703 

Heraeus (hearing) 0642 

1-15 
Chapter 1: Rulemaking Process and Cross-Program Issues 

1.2 Scope 

1.2.1 Handheld exhaust standards 

What Commenters Said: 

MECA noted that EPA chose not to consider any change in the current Phase II exhaust 

emission limits for Class III, IV, or V engines used typically on handheld equipment (e.g., 

chainsaws, string trimmers, hedge cutters). They commented that catalysts are already being 

used in many (but not all) of these handheld equipment applications. However, engine 

technology improvements continue to be made on these small spark-ignited engines to further 

improve engine-out emission characteristics. MECA believes that it is time for EPA to assess 

the need for further emission reductions from these smaller engines based on the application of 

advanced engine technologies with properly engineered and cost effective exhaust emission 

controls like catalyzed mufflers. 

NESCAUM also noted that EPA has declined to establish more stringent exhaust 

emissions standards for handheld equipment beyond the Phase II standards adopted in 2000. The 

Phase II standards were affirmed by EPA in 2004, based on a technology review, with the final 

standards taking effect in 2007 for all handheld engine classes. According to the technology 

review, EPA determined that handheld engines would meet the exhaust emissions standards on 

schedule, mostly by modifying two-stroke designs to incorporate stratified scavenging with lean 

combustion, with or without catalytic aftertreatment. Accordingly, NESCAUM fails to see why 

HC+NOx exhaust emissions standards for Class V handheld engines should remain 44 percent 

higher than the standards for smaller handheld engines. Their concern is heightened under this 

proposed rulemaking because, in effect, the Class V engine category will be expanded to 

incorporate all Class I engines with cylinder displacements less than 80 cc, regardless of whether 

these engines are used in handheld or nonhandheld applications. While NESCAUM does not 

object to treating these smaller Class I engines in all respects as Class V engines, they urged EPA 

to revisit and strengthen the Class V exhaust emissions standards through this rulemaking. 

NESCAUM commented that at the time of EPA’s technology review in 2004, 

manufacturers were concentrating their Phase II development efforts on Class IV and smaller 

displacement engines because these standards were to take effect two years ahead of the Class V 

engine standards. The speculative concerns regarding technology transfer, safety, performance, 

weight, and other factors affecting Class V engines were primarily due to the fact that 

manufacturers had not begun to focus their attention on this particular engine category. EPA’s 

subsequent Technical Study, while confined to larger Class I and to Class II engines, has since 

established that catalysts can be effectively incorporated into larger engine designs and function 

without causing some of the problems envisioned by the manufacturers. In addition, 

NESCAUM noted that at least one equipment manufacturer, Stihl, already has a line of 

professional grade chainsaws on the market that uses the smaller Class I (soon to be Class V) 

engines, incorporating stratified scavenging technology and/or catalytic converters to meet 

emissions standards. They see no basis for allowing Class V engines to certify to the most 

lenient HC+NOx exhaust standards among small SI engines and therefore urge EPA to adopt 

more stringent standards. At a minimum, NESCAUM commented that Class V engine standards 

1-16 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

should be aligned with those for smaller engines. In addition, they urged EPA to update its 

technology review of exhaust emissions standards for Class III and IV engines, and as necessary, 

adopt more stringent standards through subsequent rulemaking. 

NY DEC noted that EPA’s proposal contains no new standards for engines in handheld 

equipment, where the proximity of engine exhaust to the operator’s breathing space leads to 

individual toxic exposure concerns in addition to ambient air quality concerns. They commented 

that additional effort is necessary to identify technology supporting more stringent handheld 

engine regulations. They urged EPA to continue its efforts in this field, and build on its current 

success, ultimately promulgating more stringent regulations for all of these classes of nonroad 

engines. 

Letters: 

Commenter Document # 

MECA 0668 

NESCAUM 0641 

NY DEC 0659 

Our Response: 

In response to the comments that EPA should adopt more stringent emission standards 

for handheld engines, EPA believes the current Phase 2 standards are the appropriate standards 

for handheld engines at the current time. In fact, the Phase 2 standards for handheld engines are 

not yet fully phased-in. For Class III and IV engines, the Phase 2 standards became fully 

effective, including small volume engine families, in 2007. For Class V engines, the Phase 2 

standards became effective in 2007 except for small volume engine families. However, small 

volume engine families in Class V, which include about half of the Class V engine families, have 

until 2010 to comply with the Phase 2 standard. Therefore, most of the handheld engine 

manufacturers are still in the process of redesigning the remaining small volume engine families 

to meet the Phase 2 standards. 

An analysis of the certification data for 2008 model year handheld engines shows that the 

standards have resulted in widespread use of catalysts on Class III and IV engines, as expected in 

the final rule. Based on sales estimates, approximately 70% of Class III and IV engines are 

using catalysts to demonstrate compliance with the Phase 2 standards. (The remaining engines 

are either 4-stroke engines which can meet the standards without a catalyst, or 2-stroke engines 

without a catalyst many of which are certified through the use of ABT credits and emit at levels 

higher than the Phase 2 standard.) In addition, the 2008 certification data shows that few of the 

Class V engines are using catalysts to demonstrate compliance with the Phase 2 standards, as 

expected in the final rule. (EPA’s certification data can be found on the internet at the following 

address: http://www.epa.gov/otaq/certdata.htm#smallsi ) As detailed in the development of the 

Phase 2 standards, EPA set the Class V standard at 72 g/kW-hr in response to concerns over heat 

issues related to the use of catalysts since much of the Class V equipment is used in chainsaws 

where compact packaging requirements make it hard to design the engine with the increased 

cooling needed with a catalyst (see 65 FR 24269, April 25, 2000). In response to the comment 

that the recent testing of catalyst-equipped engines by EPA shows catalysts could be 

1-17 
Chapter 1: Rulemaking Process and Cross-Program Issues 

incorporated into larger engine designs and function “without causing some of the problems 

envisioned by the manufacturers,” EPA notes that the testing was performed on Class I and II 

nonhandheld engines which are 4-stroke engines. The results of that testing are not applicable to 

Class V handheld engines which are 2-stroke engines and completely different types of 

equipment applications offering their own issues with catalyst design and engine cooling. 

In conclusion, given that the Phase 2 standards are not fully effective, and given the 

technologies being used to comply as demonstrated in the most current certification data, EPA 

believes the Phase 2 emission standards for handheld engines are the appropriate standards for 

handheld engines at this time. This should not be interpreted to mean that EPA will not revisit 

the standards for handheld engines in the future. Indeed, under section 213(a) of the Clean Air 

Act, EPA is required to “promulgate (and from time to time revise) standards” for nonroad 

engines. 

1.2.2 Hobby engines 

What Commenters Said: 

N. Leggett (0603) commented that independent inventors and experimenters should be 

encouraged because they develop inventions that are different from the technologies developed 

by large corporations. There are hobby engines used for radio control models that are larger than 

50 cubic centimeters in per-cylinder displacement. Presumably these larger engines would be 

allowed by the statement in the rules that: “Hobby engines are compression-ignition engines with 

a per-cylinder displacement of less than 50 cubic centimeters or spark-ignition engines installed 

in reduced-scale models of vehicles that are not capable of transporting a person.” The 

commenter’s interpretation of this definition is that engines larger than 50 cubic centimeters percylinder displacement are considered hobby engines if they are installed in a model vehicle. Is 

this interpretation of this statement correct? If it is not correct, the statement should be modified 

to make it clear that a small engine in a model vehicle is not covered by these regulations. It is 

important to keep the model scale engines as a free area for the development and use of engines. 

This maintains an activity where engine designers and inventors are free to make their own 

engines without mandated design features. Some of these people use desk top machine shops 

such as the Sherline miniature lathe and milling machine systems (Reference 1). More people are 

getting involved with their own machining using computer-controlled systems. Still others are 

using full-scale metal working lathes and milling machines to build their engines. This 

developmental freedom is a contrast to the regulated engine world where people are blocked 

from “tampering” with engine features. Indeed, the very process of invention and creative 

technology design is the basically playful activity of tampering with and departing from 

conventional engine design. The commenter stated that we need free spaces for invention to 

maintain America’s position in technology and manufacturing. These engine experimenters also 

develop precious industrial skills. 

N. Leggett (0612) commented that the proposed exemption for reduced scale hobby 

engines is an excellent idea. Designing and building hobby engines is an excellent way to 

experiment with engine technology and to develop new engine inventions. 

1-18 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

L. White offered concern that this proposed regulation would make illegal the production 

of hobby kits for the construction of a small engine by an individual or student unless the 

manufacturers submit to and pass the requisite emission tests. The necessity to get such an 

engine design or personally built kit approved under these regulations would make hobby and 

educational engine building difficult at best. Putting emission controls on these engines 

sufficient to meet these standards is inappropriate for their intended historical, educational, and 

hobby recreational purpose - especially when these engines are replicas of earlier commercial 

designs that did not have these controls and when the activity is primarily for hobby, 

experimental, or personal educational use. The expense of certifying such engines and kits built 

for personal educational, hobby, or recreational use would put an end to this hobby and this 

business. The extra weight and complexity of certified engines would also most likely make 

them unsuitable for a number of hobby uses including powering RC model aircraft and small 

model water craft. These engines are produced in very limited numbers, are generally of low 

KW output, and see a very limited number of hours of annual use. The total fuel burn and the 

total emission output are simply not worth regulating. The commenter proposes that a very 

specific exclusion be incorporated in the proposed regulations such that these limited output and 

very occasional use engines and kits and the manufacturers or builders of them be exempted 

from regulations regarding emissions. 

Letters: 

Commenter Document # 

N. Leggett 0603 

N. Leggett 0612 

L. White 0620 

Our Response: 

The regulations as proposed (and currently existing) would apply the limit of 50 cc per 

cylinder for hobby engines only for compression-ignition models. This was intended to be a 

threshold below which there would likely be no commercial application other than for hobby 

vehicles. Given the confusion illustrated by the comment, we believe it is important to adopt a 

uniform set of definitions and requirements for all hobby engines and vehicles. We are therefore 

extending the proposed definition for spark-ignition engines to apply equally to compressionignition engines. Thus, any engine that is installed in a reduced-scale model of a vehicle that is 

not capable of transporting a person is exempt from emission standards. This change would also 

mean that compression-ignition engines smaller than 50 cc per cylinder that are installed in other 

applications would no longer be exempt. However, we are not aware of any such practice today. 

While we agree that there is value in allowing for innovation, development, and training 

with hobby engines that outweighs the potential environmental effects, we need to draw clear 

lines to prevent widespread use of an exemption to produce engines that could be used for other 

purposes. In particular, we see no need to expand the hobby-engine exemption to include larger 

engines or engines that are not used in reduced-scale models of vehicles for exploring innovation 

or for education. The Clean Air Act and the regulations contemplate the need for such 

innovation and development with the testing exemption (§1068.210) and the manufacturerowned exemption (§1068.215). 

1-19 
Chapter 1: Rulemaking Process and Cross-Program Issues 

1.3 Cross-cutting issues 

1.3.1 Import-specific information for certification 

What Commenters Said: 

California ARB supports EPA’s “Special Provisions for Compliance Assurance,” and 

specifically supports the provisions regarding importation data, the assurance of warranty 

coverage, and bond requirements. 

Mercury commented that the proposal contains a number of new requirements in § 

1045.205 for the content of the certification application. In particular, EPA is proposing to 

require engine manufacturers to include additional information for imported engines in § 

1045.205(z). Mercury Marine fully endorses these changes and supports EPA’s efforts to 

enforce these rules on imported engines. 

OPEI commented that it is difficult to keep intended ports of entry updated in the 

certification applications, particularly if external shipping firms are used (like DHL etc for air 

shipments). Customs exist at all ports of entry in the US so this requirement seems unjustified. 

EPA/Customs keeps a list of all US ports of entry available. All ports of entry should be 

monitored by US customs and the EPA and they should reinforce the need for proper importation 

paperwork being submitted and checked to verify compliance via the EPA database. The 

requirement should be deleted. 

EMA commented that the specific port that a manufacturer will use to import engines 

changes from shipment to shipment. For this reason, the requirement to identify the port(s) 

where a manufacturer will import engines (see §90.107(d)(15)(i) Application for certification) 

cannot be maintained in a certification document. If required to identify a port in the application, 

the manufacturer would have to submit a list of all potential ports where it may import engines. 

Such a list would not provide the sought-after information and would fail to provide the intended 

benefits associated with having this information. Therefore, this section should be deleted. 

EMA commented that the NPRM does not clearly identify who is required to name an 

agent for acceptance of service on behalf of a manufacturer. While it appears that such a 

requirement applies only to manufacturers that do not have a U.S. presence capable of accepting 

service, the final rule should clearly state that such a requirement applies only to entities without 

a U.S. presence. EMA commented that this can be accomplished by moving section 1054.205(z) 

so that it is included under (aa). However, if the requirement to name an agent for service 

remains as a separate requirement under subsection (z), the section should be revised to read as 

follows: “If you do not have a physical office in the United States with employees capable of 

being served then you must name an agent for service in the United States. Service on this agent 

.....” 

1-20 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

OPEI commented that EPA requires the location of test facilities in the US where the 

manufacturer can test engines if EPA selects them for an SEA. OPEI feels this is acceptable for 

manufacturers that do not have an established presence and compliance history (minimum of 5-

years) in the US. For those manufacturers that have an established compliance history, it should 

not be required that all families can be tested in the US. Handheld engines are very specialized 

and larger engines are hard to test. This section should be revised to indicate options as follows: 

1) Conduct the test in the lab where the certification is conducted, or 

2) Guarantee EPA access into any of your test facilities anywhere in the world, or 

3) EPA can select a lab to have engines tested in the US (if 1 and 2 are not possible). 

NMMA commented that the proposal contains a number of new requirements in § 

1045.205 for the content of the certification application. In particular, EPA is proposing to 

require engine manufacturers to include additional information for imported engines in § 

1045.205(z). While NMMA understands that some of this information may be helpful to track 

engines and avoid problems with foreign companies that are importing and selling engines in the 

U.S. that may not be covered by valid certificates of conformity, some of these requirements are 

overly burdensome. Notably, the requirement to list the location of test facilities where engines 

can be tested may not be available at the time the application is submitted. Several Marine SI 

engine manufacturers test their engines outside of the U.S. and may not have identified and/or 

contracted with test labs in the U.S. In addition, there are not that many test facilities in the U.S. 

that can perform marine engine testing. This is particularly the case with OB engines. To address 

this problem, NMMA recommends that § 1045.205(z)(3) be revised to state instead: “Provide 

upon request, Tthe location of test facilities in the United States where you can test your engines 

if we select them for testing under a selective enforcement audit, as specified in 40 CFR part 

1068, subpart E.” NMMA is supportive of EPA’s efforts to eliminate copy and noncompliant 

engines from the market and this revision will ensure that the pertinent port and agent 

information is provided but will not mandate that the manufacturer contracts with a test facility 

prior to submitting the application. 

Suzuki commented that EPA is proposing to require companies that import engines into 

the United States to identify test locations in the United States that would be used if the Agency 

requires testing under a selective enforcement audit (SEA). Suzuki is concerned that it will be 

overly burdensome to specify a test facility well in advance of any actual testing if the importer 

does not have an existing business relationship with the US-based test facility. Suzuki 

understands that there are numerous entities certifying and importing outboard engines into the 

US, and that there can be difficulties with ensuring that the importer will be held accountable 

should a noncompliance issue exist. EPA's proposal will help to address this concern; however, 

Suzuki believes it to be overly broad. Suzuki recommends that EPA revise the proposal to 

consider relevant factors when determining if an importer must declare a test facility in advance 

of a SEA test order. Suzuki believes that relevant factors could include the length of time an 

importer or distributor has been certifying engines in the US and/or the certification history of 

the importer (this could include previous SEA test history, in-use test history, responsiveness to 

prior Agency information requests, etc .) Alternatively, EPA could allow SEA testing to be 

conducted at the manufacturer's own testing location if the location was deemed appropriate by 

EPA. 

1-21 
Chapter 1: Rulemaking Process and Cross-Program Issues 

Honda commented that at the time of certification of both Small SI and Marine SI 

engines, it may not be possible to name a test facility in the United States that will be a viable 

option for testing when at some future date EPA requests a manufacturer to perform testing. For 

some engines that are manufactured or are similar to engines manufactured in the United States, 

this up-front designation may be reasonable. However, for engines requiring an outside (third 

party) test facility, it would be more appropriate to choose that test facility at the time testing is 

actually requested. Alternatively, a manufacturer could ensure that EPA representatives have 

full and open access to existing test facilities located outside the United States. 

 Manufacturers described that it would be burdensome to name a test lab, because they 

would need to make extensive preparations and do round-robin testing periodically to ensure that 

the named test lab would properly test engines. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

Suzuki 0698 

California ARB 0682 

Honda 0705 

OPEI 0675 

EMA 0691 

NMMA 0739 

Our Response: 

It can be very useful for us to understand a manufacturer’s general practice for importing 

engines into the United States. Knowing which ports a manufacturer uses would help us target 

certain engines for more careful monitoring or inspection if there were a cause for concern or a 

need to identify engines at the port for a selective enforcement audit. We acknowledge the 

manufacturers’ concern that they should not be limited to any particular ports identified in the 

application for certification, given the dynamic nature of shipping engines and equipment. To 

address this concern without simply deleting the provision, we are modifying the regulatory 

language to specify that importing manufacturers must identify the ports through which they 

have imported certified products in the previous 12 months. This limits the submission to 

factual, historical information that is readily available. 

It is not clear why EMA would object to naming an agent for service in the United States. 

We have a need to know whom to contact if there is a need for official communication, 

regardless of the location of the company. It is especially important to require this for companies 

based outside of the United States to ensure that there is a point of contact. It is self-evident that 

companies located within the United States can be contacted, but there is still a strong advantage 

to knowing before an issue arises that there is an established contact person to handle official 

communications. This could be as simple as identifying the person submitting the application 

for certification as the agent for service. As such, we would understand that there is no burden 

associated with this requirement and are adopting it as proposed for all companies. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Independent of the proposal requiring manufacturers to name a test lab in the United 

States, the regulations state that we may specify any test lab for measuring emissions from 

certified engines (§1068.401). As long as the emission measurements conform to the specified 

procedures in 40 CFR part 1065 and in the standard-setting part, the results would be considered 

valid for determining whether or not the engines meet emission standards. As a result, the 

provision to name a test lab in the United States does not expand the manufacturers’ liability but 

rather gives the manufacturer the opportunity to plan ahead of time to identify a lab where 

arrangements can be made to ensure that the testing will be done properly. 

We believe it is important to preserve the proposed requirement to name a test lab in the 

United States. This would allow us to promptly pursue a selective enforcement audit for 

imported engines where we find that to be necessary or appropriate. Under selective 

enforcement audits, manufacturers test freshly manufactured engines, at their own expense, to 

determine whether they meet applicable emission standards. It may not be practical to pursue 

testing if the engines need to be shipped back to the country of origin. This is especially true in 

countries where EPA agents would not necessarily be able to freely travel or perform official 

functions. Testing in the United States also allows us to require statements and submission of 

information where U.S. laws apply, including the requirement to submit truthful information to 

the government (with the corresponding civil and criminal penalties for violations). This 

requirement removes an inherent advantage for imported engines, since there will always be a 

U.S. lab available for testing domestically produced engines. It also serves as a preventive 

measure by forcing manufacturers to recognize that they are liable for the compliance of their 

engines even after they have been sold. 

The manufacturers raised several specific objections, none of which address the 

fundamental issues described above. First, it would be impractical to require manufacturers to 

name a test lab “upon request” at the point of importation. Manufacturers have already stated 

that they don’t want to test engines in the United States, so this request would likely be met with 

resistance and delay. The resistance would be greatest in cases where domestic testing is most 

needed. As described above, we could in any case pick any test lab without the manufacturer’s 

direction, so we believe it is in the manufacturer’s best interest to name the test lab at 

certification. 

Second, manufacturers could provide statements regarding their commitment to ensure 

access to test labs located in other countries, but that is not always reliable. Manufacturers 

would offer such assurances at certification whether or not they intended to cooperate, or 

whether or not local government officials would cooperate. The burden would be on EPA to 

identify engines for testing, then possibly find that the manufacturer is not willing or able to 

follow through on its commitment. This would also put EPA in an awkward position, which 

would likely again result in tests being run at a test lab in the United States where no prior 

arrangements had been made. This outcome would not be in the best interest of EPA or the 

manufacturer. 

Third, we believe any published measure of good compliance history is not appropriate 

for excluding a manufacturer from the responsibility to name a test lab in the United States. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

However, we may take this into account in deciding whether to allow the manufacturer to 

conduct testing in the country of origin or not. The testing in question may be what we need to 

establish whether or not a manufacturer has been producing noncompliant engines. Also, with 

the very large number of certifying manufacturers and emission families, it is easy to imagine 

that a manufacturer could be in violation for a considerable period without being caught. 

Creating this exception would inappropriately reward companies that are able to avoid detection 

of violations. 

Fourth, we believe there are labs available for testing almost all kinds of engines, 

including large and small engines, and all sizes of outboard engines. To the extent that 

manufacturers depend on special test procedures or specialized test equipment, we would 

cooperate with the manufacturer to ensure that testing can be done properly. However, we have 

modified the original proposal to create two exceptions. Manufacturers are generally not 

required to name a test lab for engines rated over 560 kW. These engines are much more 

expensive and are sold in much smaller volumes, so any effort to test these engines would 

necessarily involve considerably more effort to make those arrangements. For engines above a 

certain size, there are also very few if any locations available for testing. Also, manufacturers of 

Small SI engines may omit naming a test lab for engine families where testing depends on 

custom test fixtures that are not available without making special arrangements. This allowance 

is limited to engine families representing less than five percent of a manufacturer’s total U.S.-

directed production volume of Small SI engines. While we are waiving the requirement to name 

test labs for these special cases, we may still require manufacturers to do selective enforcement 

auditing with these engines by testing them in the United States to the extent that is possible, but 

we are not requiring the companies to prepare for that by making these arrangements ahead of 

time. 

We understand that manufacturers would be well served to invest some effort in 

coordinating with the named test lab to ensure proper testing. On the other hand, the fact that 

manufacturers are concerned that another lab may get different results reinforces our concern 

that this provision is necessary. Testing of certified engines should show that the engines meet 

emission standards for any valid test, regardless of the test location. 

Manufacturers might also name multiple test labs if they have made arrangements with 

different companies that perform such testing. If manufacturers are confident that a valid test at 

any facility will show that their engines comply and they have no relationship with testing 

organizations in the United States, they might also indicate in the application for certification 

that all test labs in the United States are acceptable for confirmatory testing. 

When we select imported engines for testing, we expect to work with the manufacturer to 

make the necessary arrangements. We would generally plan to test engines in the United States. 

However, in certain circumstances we may agree to allow testing in the country of origin if we 

have reason to believe that the testing will be properly performed and that we will have 

unrestricted access to the foreign test facility. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

We are therefore adopting the proposed requirement to name a test lab in the United 

States, with the modifications noted above, as supported by Mercury Marine and California 

ARB. 

1.3.2 Date of manufacture on label 

What Commenters Said: 

ISMA commented that they do not support the recommended change to § 1051.135(c)(6). 

EPA has proposed to remove the flexibility of keeping records of the manufacture date in lieu of 

printing the month and year of manufacture on the label. This change results in a large burden 

on the manufacturer with no benefit to the environment. Each vehicle must have its certified 

engine family name on the emission control information label. The vehicle or engine’s model 

year is clearly indicated on this label through the first character. Since the EPA snowmobile 

regulation is based on model year, not calendar year, placing the month and date of manufacture 

on the label does not provide meaningful information. ISMA manufacturers will continue to 

maintain records of build dates for their vehicles, and respectfully requests EPA maintain the 

current language in 40 CFR 1051.135(c)(6). 

MIC commented that § 1051.135(c)(6) allows omitting date of manufacture from the 

label only if the date is stamped on the engine/vehicle. Stamping each vehicle or engine with the 

build date is burdensome and unnecessary. The rationale for this change is that it is needed for 

verifying that vehicles comply with standards based on their build date. However, it is also 

required that the label “state the exhaust emission standards or FELs to which the vehicles are 

certified (in g/km or g/kW-hr).” Given this requirement, the build date is unnecessary. 

Arctic Cat submitted a comment regarding §1051.135(c)(6). The new proposal will 

require that the date of manufacture is included on the Vehicle Emission Control Information 

(VECI) label. Arctic Cat requests an exemption from this requirement for replacement labels 

(usually needed when a replacement tunnel is provided to a snowmobile customer). These 

replacements number about one hundred per year to service all past production. Since this affects 

used units that have already cleared customs and are no longer in a dealership there is little value 

in making the extra effort to ensure a correctly dated VECI label is supplied. Arctic Cat proposes 

including the phrase "replacement label" in the field for the date (shortened if necessary to fit in 

field). The difficulty of including the date on a replacement VECI label is that it is too resourceintensive to create the label and manage the logistics to make sure this exact label is supplied to 

the customer. 

Honda also commented on the pending regulatory changes to §1051.135(c)(6). Honda 

has not had sufficient time to evaluate the impacts and requirements this proposal will have on its 

production efforts. Honda requests EPA’s approval to not include the production date for the 

2009 model year. 

Honda continued that the current regulations allow them the opportunity to not print the 

date of manufacture on the VECI labels as long as they stamp the date on the vehicle or maintain 

records and provide them to EPA upon request. As EPA is aware, the proposed regulation does 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

not include the option to maintain records and provide them to EPA upon request. Honda would 

prefer to maintain records of the manufacturing dates, as they are currently doing, and provide 

them to EPA upon request. Honda questioned whether there was a particular reason why this 

option was no longer being provided. With the issuance of the Final Rule being delayed so close 

to the start of the 2009 model year, Honda noted that several months will be required to prepare 

and implement the printing of the production date on the VECI labels. This can have a 

significant impact on their early model year production. 

Suzuki commented that as a motorcycle manufacturer Suzuki is concerned about the 

labeling requirement proposed in § 1051.135(c), as this is a totally new requirement. They 

supported the MIC comments on this issue, which reflected their position. Additionally, Suzuki 

questioned whether they can assume that a MY 2010 effective date will be applied to whatever 

revisions to part 1051 are finalized. 

MIC reiterated its concerns with EPA’s proposed changes to the Recreational Vehicle 

regulations at 40 CFR part 1051.135(c)(6). The current regulation allows the date of manufacture 

to be omitted if a manufacturer keeps a record of the date and provides these records to EPA 

upon request. This change is of concern to manufacturers because the increased burden is 

significant. MIC argued that there is no benefit from requiring this of mainstream established 

manufacturers. This change appears to be targeted at EPA’s oversight of importation of 

nonmainstream engines and not control of established manufacturers, therefore a more 

appropriate approach should be found to address the problem without overly burdening 

compliant manufacturers. MIC wants to reiterate that this requirement change will impose 

significant problems for the following reasons (but not limited to): 

- Space allocation on engine emission labels is very limited; on many smaller engines 

emission label space is extremely limited 

- Emission labels are often not printed at the factory and therefore it is not possible to create 

a unique emission label reflecting the manufacture date 

- Even if it is possible to incorporate the date on the emission label, sufficient lead time is 

not provided in the regulation change to provide for 100% assurance of labeling accuracy 

- Many engines do not have space for incorporating an engraved date and would require 

revised casting (extremely expensive) 

- Even if space is available on the engine for engraving the date, plants are not equipped for 

performing this engraving operation (expensive equipment and production line changes are 

required) 

In addition to the above implementation issues, MIC stated that recreational vehicle 

engines are not considered complete until they are assembled into the vehicle. If the 

manufacturer identifies the date of manufacture on the vehicle and the engine has a separate label 

stating a different date of manufacture; unnecessary confusion (not to mention redundancy and 

cost) will result. MIC believes that the current approach of requiring the manufacturer to have a 

readily available tracking method for the assembly of partially complete engines is sufficient and 

that an additional label on the engine adds no benefit. 

MIC is interested in continuing to work with EPA on developing a method for addressing 

whatever the basis is for making this change in the regulation but does not agree that the current 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

approach is acceptable. MIC requests that at the very least EPA should provide additional lead 

time for the above issues to be properly addressed in the production process and that 

implementation should be no earlier than model year 2012. 

In later comments, MIC emphasized that this was an important issue for them. They 

stated that they understood EPA's rationale for the requirement to identify the engine build date 

on the engine or vehicle, but pointed out that the implementation date for this requirement 

prohibits the use of labels that have already been printed by the manufacturer. The MIC 

proposed language below would allow for the engine build date to be printed on a supplemental 

label that is affixed adjacent to the main emission control information label: 

§ 1051.135(c)(6) State the date of manufacture [MONTH and YEAR]; however you may 

omit this from the label if you stamp or engrave it on the engine or vehicle, or if you provide 

this information on a supplemental label. If you use a supplemental label, it must be visible 

when viewing the primary emission control information label and comply with the 

placement, durability and legibility requirements as described in this part. 

Letters: 

Commenter Document # 

ISMA 0671 

MIC 0701 

Arctic Cat 0709 

Honda 0736 

Suzuki 0732 

Our Response: 

Under the Clean Air Act, engine certification is based on annual production schedules (or 

model years) where a manufacturer produces each engine during a production period such that it 

is covered by a valid certificate of conformity. Identifying an engine’s build date establishes 

clearly for each engine whether it is covered by a certificate of conformity for any given model 

year. Properly associating each engine with the appropriate model year is important for 

identifying applicable emission standards, calculating emission credits (where applicable), 

tracking emission-related defects, and executing a recall, among other things. We are adopting 

regulatory provisions in this rule that further clarify the concept of build date, model year, and 

the effective dates of certificates of conformity in 40 CFR part 1068 for all nonroad engine 

categories and in the standard-setting parts. We believe each engine should be clearly 

identifiable with a certain model year based on its build date. Having this information recorded 

on the engine prevents a situation in which a manufacturer could manipulate records as needed to 

gain a more favorable outcome depending on the reported build date of any particular engine or 

engines. For example, we may find a collection of engines in violation and would want to 

establish whether they are from the same model year or not, or whether they were built before or 

after a given change in the application for certification. Our experience has shown that it is very 

difficult to contest a manufacturer’s claimed build date, even when it defies any customary 

business or manufacturing process. We also find it inappropriate generally to have to depend on 

manufacturers to provide information that is necessary to determine whether that manufacturer 

has committed a violation. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

A further practical constraint comes from engine inspections, especially at importation 

where U.S. Customs and Border Patrol agents have limited time to evaluate large quantities of 

very diverse products. Inspection of engines often depends on knowing an engine’s build date to 

establish which tier of emission standards apply. A straightforward inspection of an engine 

should allow an inspector to determine the applicable standards. 

Having the build date on an engine would also provide a valuable piece of information 

because the manufacturer makes a commitment in the assembly process by printing a specific 

date on the engine (generally month and year). This information is necessary for us to be able to 

evaluate whether an engine was produced before or after the effective date of a certificate of 

conformity. The printed build date information is unalterable, which is very effective for both 

compliance assurance (or prevention of noncompliance) and enforcement. For example, 

manufacturers would be very reticent to put a false date (such as a postdate) on an engine if there 

was a possibility that someone may inspect that engine shortly after the manufacturer introduces 

it into commerce and where it would be directly evident that the date is in error. Likewise, if the 

printed date is substantially earlier than the actual production date, it may be possible to inspect 

associated records to evaluate the validity of the printed date (production records by serial 

number, build dates of equipment in which the engine is installed, invoices, bills of lading, etc.). 

Having the ability to demonstrate that an engine was produced after emission standards started to 

apply is essential both for our benefit to ensure compliance, and for the manufacturer’s benefit to 

prove compliance. 

Furthermore, where there is a compliance problem, it may be easier to demonstrate that a 

false build date is a violation than that the engine exceeds emission standards. Requiring build 

dates on labels requires that manufacturers make a statement to the government, where penalties 

may apply if the information is demonstrated to be false. 

We allow for applying the label and identifying the date of manufacture at any point in 

the assembly process. Manufacturers could use pre-printed labels that are punched to identify 

month and year, or the label printing could be brought in as part of the assembly process. 

Manufacturers may also identify the date of manufacture elsewhere on the engine, such as on a 

different label applied for other purposes. In any case, the manufacturer could take steps to 

avoid mismatched dates on different labels if that is a priority objective. 

We acknowledge the concern for labels on replacement components. We understand this 

to be a relatively rare occurrence and agree that it would be rather impractical to include build 

dates on these replacement components without a disproportionate effort. We are including this 

exception in the new language related to replacement labels in §1068.101(b)(7). 

We are adopting the proposed requirement to print build dates on the label. We 

understand that this will involve a change in labeling practices for some companies. On the 

other hand, manufacturers of Small SI and Marine SI engines have already been doing this for 

several years so the feasibility of identifying engines this way is well established. This is part of 

a broader effort to adopt this requirement across engine categories. We intend to further 

standardize labeling with further specification related to the format of the build date. For 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

example, we believe it is not appropriate to identify the date with coded alphanumeric characters 

intended to disguise the information from anyone who is not privy to the coded meaning. 

Spelling out the full date is clearly acceptable. We would also consider acceptable certain 

standard abbreviations, such as Sep 10 or 09/10 to indicate September 2010. We plan to propose 

detailed specifications in a future rulemaking to describe a range of acceptable ways to identify 

an engine’s build date. 

We agree with MIC’s concern that multiple dates on a single engine or vehicle would be 

confusing and unnecessary. We have therefore modified the labeling requirement to say that 

permanently applying the date elsewhere (not just by stamping or engraving on the engine) 

would be acceptable for meeting specifications. Given that manufacturers of recreational 

vehicles are already putting build dates on their vehicles, we believe there is no need to delay this 

requirement beyond the 2010 model year. 

1.3.3 General labeling provisions 

What Commenters Said: 

EMA commented on regulatory language we introduced in a new §1068.45 to lay out 

general labeling requirements. These comments included the following suggestions: 

• Using the term “removable label” throughout part 1068 in place of the term “temporary 

label.” 

• Including an example to illustrate that a removable label for replacement engines should 

remain in place until the exemption no longer applies. 

• Allowing hang tags to qualify as removable labels since they can be made durable 

enough to stay in place until they are removed. 

• Referring to §1068.101 in §1068.45(e) in regard to improper removal of labels is vague 

and should be removed. 

EMA said the provisions in §1068.101(b)(7) regarding label removal should include an 

allowance for removing and replacing labels that are incorrect, whether they were wrong initially 

or they were rendered inaccurate by an engine modification. 

In addition, EMA commented that the regulations in several instances specify that labels 

for exempted engines include information related to engine displacement and rated power. They 

argued that this information should not be required. 

Letters: 

Commenter Document # 

EMA 0808 

EMA 0810 

Our Response: 

We believe it is quite appropriate to point readers to the provisions in §1068.101 that 

describe provisions related to label removal. This does not change any of the regulatory 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

requirements, but we believe readers may not be aware of those provisions without a specific 

reference. We agree with EMA’s other suggested changes to §1068.45 and have incorporated 

those into the regulations. 

We agree with EMA’s suggestion to allow for removal of incorrect labels. A single 

statement can cover both of the scenarios EMA highlights; a label is incorrect anytime it is no 

longer true, whether that was always the case or the engine’s original, correct label is no longer 

accurate. We are also including language to clarify that the allowance to remove and replace 

labels does not change the fact that applying an original label that is incorrect may be a violation 

of the prohibited acts. We simply intend to allow for the manufacturer to rectify incorrect labels 

and would separately consider the original action of applying a false label. 

In almost all cases, we want labels on exempted engines to identify the engine’s 

displacement. This is important identifying information that helps to prevent a situation in which 

an exempt label is applied to the wrong engine. Identifying the displacement helps the engine 

manufacturer and anyone inspecting the engine to know that the labeled engine is properly 

covered by the exemption in question. We agree that rated power is generally not needed. 

However, in certain cases, we might approve an exemption only for certain power ratings for a 

specific engine model. For those few exemptions where we might want manufacturers to 

identify an engine’s rated power, we have modified the regulation to allow us to require that if it 

is needed. In no cases do we have a default requirement to identify the rated power for exempted 

engines. 

1.3.4 Special provisions for production-line testing 

What Commenters Said: 

MIC commented on §1051.301(a)(2) of the proposed regulations. MIC commented that 

the exemption from PLT for small volume families should not be left to the discretion of EPA 

staff. The proposed language states that the exemption “may” be provided. The language of 

§1051.301(a)(2) should be revised to say “Engine families with a projected U.S.- directed 

production volume below 150 units are exempt from testing under this subpart.” 

ECO commented that EPA should allow small-volume engine manufacturers to utilize 

the use of alternative testing methods (portable emissions analyzers) to demonstrate in-use field 

testing compliance for production units. 

Letters: 

Commenter Document # 

MIC 0701 

ECO 0712 

Our Response: 

We continue to believe it is appropriate for manufacturers to be required to request a PLT 

exemption for small-volume engine families in the application for certification. For example, we 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

are concerned that manufacturers may attempt to gain an advantage by underestimating projected 

sales. The request process should be fairly simple, since manufacturers are required to certify 

each of their engine families and they must submit a sales estimate. We would grant or deny the 

exemption request as part of the certification approval process. We have added language to the 

regulations in each of the applicable standard-setting parts to clarify that we would approve the 

request if we agreed that the projected sales volumes were made in good faith. 

We agree with ECO’s suggestion to clarify the language related to alternative methods for 

production-line testing. The original language was intended to allow for manufacturers to 

develop different ways of testing production engines for proper quality assurance with respect to 

emission controls. The initial thinking was that a simpler test (such as ppm testing at multiple 

modal points) on a large number of engines could be more effective at screening production 

engines than a rigorous (certification-quality) test on a small number of engines. We continue to 

believe there is a good potential for this type of alternative test program. The specific suggestion 

to allow the use of field-grade measurement equipment for production-line testing is an 

appropriate additional alternative. We have modified the regulation for all spark-ignition 

engines to allow for using field-grade measurement equipment, provided that the manufacturer 

doubles the minimum sampling rate. Much like the ppm testing described above, the somewhat 

less precise or accurate test methods should provide an equivalent compliance demonstration by 

expanding the sampling rate. We would expect portable analyzers to reduce the cost of testing 

enough to more than offset the burden associated with testing additional engines. Note that 

testing with portable analyzers that meet lab-grade specifications would not be considered an 

alternative test method and would therefore not be subject to EPA approval and would not 

trigger the need to increase the sampling rate. 

1.3.5 Reporting and recordkeeping requirements 

What Commenters Said: 

Kohler Co. is very concerned with the record keeping and reporting burden associated 

with the proposed regulation. Table XIV-l in the proposal lists the average burden for a Small SI 

engine manufacturer at 885 hours annually. This is reported to be the total estimate for both new 

and existing reporting requirements for total time required to “generate, maintain, retain, or 

disclose or provide information to or for a Federal agency.” This equates to less than half time 

for a person working 40 hours per week. Kohler knows this estimate is grossly understated and 

that they will need to add additional staff to deal with all of the record keeping, reporting, 

correspondence with customers and auditing required by the proposed regulation. 

Kohler continued that it appears that in drafting the regulation, the Agency, in its drive to 

ensure manufacturers sell compliant engines, has incrementally added requirements until the 

total burden is excessive. They ask the Agency to take a careful look at the proposed regulation 

from the prospective of those who need to comply. Kohler asked that we make it more “user 

friendly” and cost effective by eliminating all unnecessary record keeping and reporting. They 

said that the resources required to perform this unnecessary and burdensome recordkeeping, 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

reporting and paperwork is time and effort that cannot be expended on cleaning up the engines to 

provide real environmental benefits. 

Kohler commented on the following, but certainly not all inclusive, examples of sections 

in the regulation where we feel reductions can and should be made: 

§91.1013 — Exemption for certified Small SI engines 

This section includes a reference to § 1045.605 which requires that small offroad engines 

(SORE) used as marine propulsion engines must have special labeling and record keeping. 

Kohler feels this is unnecessary since the engines are already labeled as compliant to the 

SORE regulation and represents an additional undue burden for manufacturers. 

§1054.130 — What installation instructions must I give to equipment manufacturers? 

Kohler feels there is a significant burden on engine manufacturer regarding evaporative 

emissions and general installation instructions. 

§1054.205 — What must I include in my application? 

Paragraph (a) requires for each engine configuration inwhich the maximum modal power is 

at or above 15kW a listing of the maximum power and the range of values for maximum 

engine power resulting from production tolerances. Kohler feels this is another unnecessary 

reporting burden. 

Paragraph (r) requires describing how engines comply with emission standards at varying 

altitudes and atmospheric pressures. Kohler suggests this will be a significant reporting 

burden that is not required today. 

§1054.610 — What is the exemption for delegated final assembly? 

Paragraph (c)(6) requires keeping records to document how many engines are produced 

under this exemption. Also, manufacturers need to keep records to document contractual 

agreements under paragraph (c)(3) of this section. 

Paragraph (c)(3) describes a contractual agreement with equipment manufacturers and the 

records required for this, so this section essentially is requiring the keeping of records on the 

keeping of records. In general, Kohler feels this section’s description of the recordkeeping, 

labeling, and auditing appears overly complicated and confusing to the point that it will be 

commerce restricting. 

§1054.825 What reporting and recordkeeping requirements apply under this part? 

Kohler believes there are significantly more reports and recordkeeping than in Part 90; EPA 

needs to review and make them more manageable. 

EMA commented on §1054.825 “What reporting and recordkeeping requirements apply 

under this part?” Kohler stated that the report and recordkeeping requirements set forth in this 

section are significantly more substantial than those currently required by 40 CFR Part 90 and 

are overly burdensome. Kohler said that EPA should review the proposed requirements and 

make whatever revisions are necessary in order to reduce such requirements and decrease the 

substantially increased compliance burden associated with the proposed regulation. 

MIC commented that § 1051.825 states that “the following items illustrate the kind of 

reporting and recordkeeping we require for vehicles regulated under this part.” The title of this 

subsection is “What reporting and recordkeeping requirements apply under this part.” To be 

consistent with the title and the presumed intent, the statement should be revised to read “The 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

following items are the reporting and recordkeeping we require for vehicles regulated under this 

part:” 

Letters: 

Commenter Document # 

Kohler 0703 

EMA 0691 

Motorcycle Industry Council 0701 

Our Response: 

We agree that the proposed rule included several new reporting and recordkeeping 

requirements. We have been careful to include only requirements that we believe are necessary 

to allow us sufficient ability to oversee these programs to ensure that we can adequately 

implement and enforce the regulatory requirements. The final rule includes several adjustments 

to take into account the interest in reducing the compliance burden wherever possible. We take 

Kohler’s list of suggested opportunities for reducing the recordkeeping burden to illustrate our 

interest: 

§91.1013: We agree with Kohler that Small SI engines used for marine propulsion should not 

trigger new labeling or recordkeeping requirements. For bigger engines we would be concerned 

about creating a path for manufacturers to rely on an existing certification to avoid requirements 

that apply specifically to marine engines. However, the relative stringency of standards and the 

extent of sales for certified Small SI engines used for marine propulsion lead us to conclude that 

a simple exemption from the marine requirements is appropriate. 

§1054.130: We would expect that engine manufacturers are already providing equipment 

manufacturers with installation instructions to address basic parameters such as inclusion of 

intake or exhaust system components that meet performance specifications and placement of 

exhaust components to ensure safe operation. The incremental effort to identify those items 

necessary to ensure that engines and fuel systems are in the certified configuration after 

installation in the equipment should be very small. In fact, we would expect engine 

manufacturers to do this even if it were not required because they are liable for the emission 

controls after the engines are installed. The installation instructions serve more to define the 

limits of proper installation so it will be clear that it is the equipment manufacturer’s fault if 

engines were not installed according to the instructions. 

§1054.205: Knowing whether engines are covered by one program or another is fundamental. In 

the case of Small SI engines, this hinges largely on the maximum engine power. We believe it is 

very reasonable to require manufacturers to identify the maximum engine power for engines that 

are approaching the thresholds established in the regulation. We are reducing this burden for the 

final rule by revising the regulation to more carefully identify those engines that are close 

enough to the threshold to warrant this reporting. 

§1054.205: Manufacturers are required under part 90 to comply with emission standards at 

altitude, though the regulations allow manufacturers to do this with an altitude kit. However, 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

since part 90 includes no reporting or recordkeeping requirement, we have no reason to believe 

manufacturers are taking any steps to ensure that their engines meet emission standards at 

altitudes different than at the lab used for certification testing. We believe the new regulations 

provide a minimal reporting and recordkeeping burden associated with the conditional allowance 

to meet standards at high altitudes based on the use of engine modifications to install an altitude 

kit. 

§1054.610: We understand delegated assembly to be an optional provision that manufacturers 

can exercise to help in cooperative relationships with component suppliers and equipment 

manufacturers to assemble finished products. Since catalysts are such a fundamental part of the 

emission control system, several measures are needed to ensure that engines in final installations 

are properly assembled such that they are in the certified configuration. The contractual 

arrangements, labeling, audits, and other measures are necessary to give us the confidence that 

engines will be routinely assembled properly. If the burdens of this oversight are too great, 

manufacturers can simply default to the normal plan contemplated in the regulation, which 

involves engine manufacturers shipping only engines that are already in the certified 

configuration. This is common across EPA programs today. 

With regard to the comment on §1051.825, the new text in §1051.825 (and similar 

sections in other programs) is intended to help us administratively in the effort to maintain 

current information collection requests with the Office of Management and Budget and to align 

with the list of approved information collections in 40 CFR part 9. While we have attempted to 

provide a complete list of recordkeeping requirements in this new section, we cannot be certain 

that it is absolutely comprehensive. This becomes especially true from a long-term perspective, 

since we may add requirements and inadvertently omit those requirements from §1051.825. We 

would not want a manufacturer to be able to claim that a reporting or recordkeeping requirement 

that is clearly stated elsewhere in the regulation is not valid simply because it was omitted from 

§1051.825. We are therefore keeping the language unchanged as illustrative of the requirements 

that apply throughout part 1051. 

1.3.6 Inventor issues 

What Commenters Said: 

N. Leggett commented that we need to encourage the independent inventors who design 

and build their own full-scale spark-ignited engines. Experimental engines should be 

automatically exempt from regulations. The inventor should not have to apply for some sort of 

exemption. Rather the exemption should be automatically applicable to single engines that are 

built by experimenters themselves. These individual experimenters should not be considered to 

be engine manufacturers. 

N. Leggett commented further that the opportunities to experiment with engines are of 

major importance to the economic and social future of the United States. Independent inventors 

and experimenters should be encouraged to experiment with engines. Their activities will lead to 

the development of new engine technologies. 

1-34 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

N. Leggett also commented that a community of skilled hobbyists restores antique 

gasoline engines to operating condition. They operate their engines on occasion including 

showing them in action at shows and rallies of antique engine enthusiasts. Some of these people 

install their restored engines in restored or rebuilt antique boats. These people perform a useful 

function in the study and appreciation of American history. They too should be encouraged in 

their efforts to bring antique technology back alive. These engines should have automatic 

exemptions to the proposed emissions rules. In addition, a related activity to the restoration of 

antique engines is the building of replica antique engines from kits. Many of these kits are in the 

form of rough castings that the builder then machines into an operational engine. This type of kit 

building is a challenge to one’s shop skills. Other kits are based on already machined parts. 

Many of these engines are small displacement hobby engines, but not all of them are small. 

These kits should also be automatically exempted. 

N. Leggett commented that these exemptions to the proposed regulations are needed to 

establish a free zone where experimenters and inventors are free to develop their own engine 

designs and inventions. This is a contrast to the regulated engine world where people are 

blocked from “tampering” with engine features. Indeed, the very process of invention and 

creative technology design is the basically playful activity of tampering with and departing from 

conventional engine design. We need free spaces for invention to maintain America’s position in 

technology and manufacturing. 

Letters: 

Commenter Document # 

N. Leggett 0603 

Our Response: 

We believe it is very problematic to introduce an exemption specifically for inventors’ 

experimental engines, or homemade engines. An experimental-engine exemption as 

recommended in the comments would be impossible to enforce. Without a request or approval 

process, there would be no way of confirming that engines produced under such an exemption 

would in fact meet even the minimal conditions described for the exemption. The Clean Air Act 

and the regulations contemplate the need for experimental engines with the testing exemption 

(§1068.210) and the manufacturer-owned exemption (§1068.215), as described in Section 1.2.2. 

The testing exemption in particular would allow inventors to build, test, and operate their 

experimental engines. EPA’s role in evaluating such exemption requests would be to confirm 

that the scope of the exemption is appropriate for the company or individual requesting the 

exemption and that the applicant understands the responsibilities associated with the exemption. 

The commenter’s interest in an exemption for antique engines is mostly unnecessary. To 

the extent that someone restores engines that have already been placed into service or installs 

such engines in restored vehicles, these engines are not subject to standards and therefore no 

exemption is needed. Building replicas of antique engines is a different matter. To the extent 

that these antique engines meet our definition of “engine,” they are subject to emission standards 

and therefore must either be certified or qualify for an exemption. These engines may qualify in 

some cases for the hobby-engine exemption. In other cases, the Clean Air Act and the 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

regulations contemplate this scenario with the display exemption (§1068.220). However, this 

exemption is available only to companies that hold a valid certificate of conformity with EPA. 

As described above, adding an exemption as recommended by the commenter would lead to a 

situation where we would be unable to confirm that engines are being exempted appropriately. 

For example, the more common form of building replica engines is for a company to build 

knockoff engines, imitating an engine by disassembling it and “designing” parts for a new 

assembly by carefully measuring the original parts. This is a very significant compliance 

problem. We believe there is not enough value in preserving an allowance to build new, fully 

functioning, replica engines to outweigh the compliance and enforcement problems that would 

result. If someone wants to build such an engine, that would be allowable as long as the engine 

does not include a crankshaft. Such an exercise would still provide plenty of challenge for 

machining and assembly; however, the value of the resulting assembly would be limited to 

display purposes, without the benefit of producing usable power. 

Innovation is clearly important to our future economic health and welfare. Our interest is 

in preserving a free zone for innovation without creating a zone where companies are free to 

produce large numbers of noncompliant engines. Even under the current requirements we are 

finding many thousands of engines that are being sold illegally. Any relaxation of current 

requirements would therefore need to be done very carefully to avoid making this situation 

worse. We understand that some inventors may find the paperwork and approval requirements 

to be burdensome, but we believe the current regulatory framework allows for innovation with a 

minimum of administrative requirements. 

1.4 Amendments to engine-testing provisions in 40 CFR part 1065 

We adopted extensive changes to the test procedures in part 1065 as part of the rulemaking 

to set emission standards for locomotive and marine diesel engines. We have identified a few 

additional revisions that we are including in this final rule. Some of these changes are necessary 

to address issues related to Small SI or Marine SI engines. Other changes involve corrections or 

clarifications of a more general nature. 

What Commenters Said: 

California ARB commented that EPA is proposing to allow the use of non-dispersive 

ultraviolet analyzers (NDUV) to measure NOx emission levels in addition to the currently 

accepted chemiluminescent detector (CLD). California ARB generally allows the use of 

alternative measuring methods if a manufacturer can demonstrate equivalency with the current 

accepted method. Recently, a manufacturer requested California ARB’s approval to use NDUV 

to measure NOx levels for small off-road spark-ignited engines. In response, California ARB 

requested the manufacturer provide data to show equivalency between emission results from 

NDUV and CLD. The manufacturer referenced a 2002 study conducted at EPA facilities wherein 

testing of NDUV technology for NOx measurement was performed on gasoline powered light 

duty passenger vehicles. However, it is worthwhile to note that despite the results of the study, 

EPA has not approved the use of NDUV for NOx measurement for light-duty gasoline vehicles. 

The manufacturer also provided limited test data from a single small spark-ignited engine. The 

data provided by the manufacturer did not indicate high correlation between the two methods 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

and, instead, raised questions about the use of NDUV for official certification purposes at this 

time. California ARB requested EPA establish a test program to generate data and determine if 

high correlation between NDUV and CLD measurement technologies exists before allowing its 

use to measure NOx emission levels in small off-road spark-ignited engines. 

EMA commented that the requirement to obtain speed and load data at 5 Hz update rate 

is not necessary for steady state testing (§1065.110(e)). EMA recommends that for steady-state 

testing the data acquisition requirement be amended to 0.5 Hz minimum. 

EMA commented that new analyzers are not configured for adjustability of FID response. 

Accordingly, §1065.360 should be revised to reflect current analyzer industry practice. 

EMA commented that the complete engine mapping procedure defined in §1065.510 is 

not required for Small SI engines. The Part 1065 requirement should include clarification that 

this requirement can be omitted per the standard setting part. 

Cummins commented on draft language to amend the requirements related to cyclevalidation criteria in §1065.514. They would still have to use §1065.514(f)(3)(i) because (ii) [the 

new provision based on existing requirements in part 90] does not use the statistical method. If 

there was going to be a mode-by-mode validation allowance in part 1065, they wanted to 

generalize it for all discrete-mode tests for consistency. The need for mode-by-mode verification 

did not seem to be unique to a specific engine size or technology. It appeared that the request 

was made to allow a lower-cost alternative method. It would be cheaper to only log average, 

min, max, etc. values for each mode rather than log 1 Hz data. If it is intended that this option 

will go away in the future, then Cummins recommended pulling it out now and putting it in part 

1054 for Small SI engines. It could then be dropped from Small SI as appropriate in the future 

without confounding testing for other engine categories. 

Letters: 

Commenter Document # 

California ARB 0718 

EMA 0691 

Cummins 0795 

Our Response: 

The performance specifications adopted for NDUV analyzers are intended to ensure that 

measurements will properly characterize an engine’s emission levels. For example, Small SI 

engines may have somewhat higher levels of lubricating oil in the exhaust stream, which could 

cloud the lens and other components of the instrument, leading to inaccurate results. However, 

under this arrangement the NDUV analyzer would not reliably meet performance specifications 

that would allow for a valid test. To avoid a situation where a manufacturer meets calibrations 

and then performs testing with other engines that may cause such a problem, we are revising the 

regulation to note that good engineering judgment may preclude manufacturers from using an 

NDUV analyzer if sampled exhaust from test engines contains oil (or other contaminants) in 

sufficiently high concentrations to interfere with proper operation. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

We revised the provisions of §1065.110 and §1065.512 to specify 5 Hz measurements for 

transient testing and 1 Hz measurements for steady-state testing. This addresses the 

manufacturers’ concern without foregoing measurement accuracy. We made these changes as 

part of the rulemaking to set standards for locomotive and marine diesel engines (73 FR 37096, 

June 30, 2008). 

We made extensive changes to §1065.360 as part of the rulemaking to set standards for 

locomotive and marine diesel engines (73 FR 37096, June 30, 2008). These changes were made 

in collaboration with EMA members. However, it is important to note that adjustability is 

critical to proper use of a FID for measuring exhaust hydrocarbons. We therefore believe it is 

not appropriate to use a FID that lacks adjustability. 

Part 1065 already includes general language stating that the standard-setting part governs 

when there is any difference in the specified procedures for a particular set of engines. If we 

were to reference every case where one of the standard-setting parts included additional or 

differing provisions, we would forego much of the advantage of adopting a comprehensive set of 

regulations that are not category specific. We are therefore not making the change to part 1065 

to include a specific reference to the lack of mapping requirements for engines subject to part 

1054. 

We agree with the suggestion from Cummins to move the new approach to cyclevalidation criteria to part 1054 so it applies only to Small SI engines. 

1.5 Amendments to general compliance provisions in 40 CFR part 1068 

1.5.1 Definition of “engine” and provisions related to partially complete engines 

What Commenters Said: 

EMA commented that the NPRM proposes a number of changes to Part 1068 which 

extend well beyond Small SI engines. Many of the proposed changes are technical clarifications 

or corrections to existing programs, and have been previously discussed with the affected 

regulated entities. While EMA has some comments on those technical clarifications, they have 

no objection to their being finalized in this rulemaking. Other changes are significantly more 

substantial and raise major new issues which have not been thoroughly discussed with the 

affected stakeholders. For example, EPA appears to be taking action, in the guise of a 

definitional change, which will substantially change the existing requirements for all nonroad 

engine service parts and engine rebuild practices. 

EMA and its members have no objection to working with EPA to better understand the 

issues that EPA is trying to address and, if necessary, to develop appropriate regulatory 

guidance. However, EPA should not adopt regulatory changes that will impact aftermarket 

engine service parts and engine rebuild practices and programs, without a separate rulemaking 

and adequate notice and opportunity for discussion, analysis and comment by all stakeholders. 

In that regard, EMA noted that the Nonroad Tier 4 rulemaking was developed, with tremendous 

success, by an extraordinary level of cooperation and outreach by and between EPA and all of 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

the affected stakeholders. EMA finds it odd that EPA would now try to adopt rules that 

significantly impact nonroad engines without a similarly thorough level of outreach. 

EMA commented that EPA’s proposed definition of an engine - a cylinder block plus one 

component - is not viable and, as a real-world matter, cannot be implemented practically. EMA 

understands that EPA has raised concerns about its ability to enforce standards if uncertified, 

incomplete engines enter into commerce. However, the proposed definition is not a viable 

means to address the concern. EMA noted that it is common for manufacturers to utilize global 

product manufacturing processes for engine parts, including engine cylinder blocks. Therefore, 

it is common practice for cylinder blocks manufactured outside of the U.S. to be imported into 

the U.S. for future assembly. In many cases, those cylinder blocks include additional parts 

depending on the economics and universal nature of the features. It is not uncommon for the 

same engine block assembly to be utilized in new engine manufacturing of products certified in 

different product categories or for use as repair parts for older engines already in service. EMA 

also commented that the proposed definition of a “partially complete engine” further compounds 

the confusion regarding the definition of an engine because it is inconceivable that an incomplete 

engine has substantially more parts than an engine (as would be the case pursuant to the 

proposed definitions). EMA believes the proposed definitions clearly require significant 

discussion with a broader industry group including both new engine manufacturers and 

remanufacturers. They believe the proposed new definition should be removed from this 

rulemaking and deferred to a subsequent process. 

NACOO commented that the new wording found in the “engine” definition of section 

1068.30 is not clear at all. It appears to be making the statements more than once with the 

addition of conflicting requirements of a complete engine and incomplete engine (i.e. the third 

sentence indicates what is not included engine blocks with no attached components). Then the 

next sentence states “This includes complete and partially complete as follows:” NACOO 

commented that the way those sentences are written seems to be saying that a complete engine is 

not an engine. NACOO commented that EPA needs a definition of “Engine Block.” They 

question whether an “Engine Block” is just a block with no crank pistons cams and just an empty 

cast iron block? They believe it is not clear what the term “Engine Block” means under the 

proposed regulations. 

ISMA commented regarding §§ 1068.260 and 1068.262: It is their understanding from 

EPA certification workshop discussions that production configuration engines destined for 

installation in a certified recreational vehicle (e.g., snowmobile) are considered “partially 

complete engines” under 40 CFR 1068.330. ISMA understands that these engines do not need to 

be permanently labeled with an emission control information label since they are not by 

themselves a certified entity – the completed recreational vehicle is. Furthermore such engines 

are covered by the temporary exemption in 1068.330 when they are imported into the U.S. The 

engines are designated on the EPA 3520-21 Form using Box F (recreational spark-ignition 

vehicles or engines) and Box 16 (incomplete engines). A hang tag or other non-permanent means 

of identifying the engines should be sufficient at the time of import. They would like to be clear 

that the ability to efficiently import these engines is critical to the snowmobile manufacturers. 

1-39 
Chapter 1: Rulemaking Process and Cross-Program Issues 

MIC commented that there are several cases impacting the MIC member companies, such 

as: 

• importation of engines not subject to stand-alone engine-based certification requirements, 

that are destined for installation in certified vehicles 

• transportation of engines not subject to stand-alone engine-based certification 

requirements, that are manufactured by a certifying vehicle manufacturer and transported 

from one of their locations to another 

• temporary labeling requirements for these and other circumstances 

MIC continued to comment that specific provisions may be needed to address engines used in 

recreational vehicles and other vehicles certified by EPA. They think the generic language in this 

section of Part 1068 does not allow proper treatment of the nuances that exist between enginebased and vehicle-based certification categories. Efficient movement of these vehicle 

components is critical to the success of several MIC member companies. 

Arctic Cat commented regarding §1068.262. This section changes the requirements for 

shipping partially complete engines within the US. They are confused by this section and are still 

studying its effect on their operations. For example, it is not clear to them how shipments from 

Arctic Cat's ATV engine factory in St. Cloud, MN to their assembly line in Thief River Falls, 

MN are affected because in this case no "secondary manufacturer" is involved. Arctic Cat 

requests additional time to study this section and provide additional comments. 

IMPCO proposes that § 1068.262 be removed in its entirety and be re-written and reintroduced at a later date. IMPCO understands EPA’s intent behind the proposed language, but 

it is impractical and will be near-impossible to implement. The main logistical issue is how the 

engine manufacturer will be able to identify not only the certifying manufacturer, but the engine 

family name. For example, IMPCO purchases engines through distributors, not from the 

manufacturer directly. IMPCO questioned how the engine manufacturer can be involved in this 

process. Additionally, IMPCO noted that they can have two or more different engine families 

using the same engine. In such a situation, IMPCO questioned which engine family will be used 

on the temporary label sent from the engine manufacturer. 

ECO commented that EPA has proposed to restrict the importation of base engines prior 

to certification approval. In addressing this issue, it is critical that EPA incorporate flexibility for 

engine manufacturers that are in the process of certifying engine families, of which the base 

engine is sourced from outside the U.S. In these instances, the Manufacturer of Records (MORs) 

are often required to import the base engines and initiate the emission control system upfit 

process prior to receiving final certification approval. In these instances, it is necessary for EPA 

to allow MORs importation flexibility for engines that are not completely assembled. 

California ARB supports the proposed requirement for partially complete engines to 

prevent manufacturers from selling partially complete engines as a strategy to circumvent 

certification procedures. Under the proposed definition, the short blocks or three-quarter blocks 

without fuel systems would need to be certified. However, EPA’s current production line testing, 

in-use testing, and warranty requirements are not designed for partially complete engines. In 

addition, EPA allows the large spark-ignition manufacturers to ship partially complete engines to 

1-40 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

the secondary engine manufacturers without emission-related components in some 

circumstances. This would make these provisions (1068.240, 1068.255, and 1068.260) difficult 

to enforce. California ARB thus recommends that EPA prepare certification guidelines on how 

to certify partially complete engines under different engine categories. Partially complete engines 

could be designed to use either gasoline or diesel fuel systems and subsequently they might be 

installed on stationary equipment, on-road vehicles, off-road equipment, or used as replacement 

engines. Preparing certification guidelines would help in circumstances when it may be difficult 

for the engine manufacturers to determine the partially complete engines’ final destination. 

OPEI commented that the definition of engine (in particular “partially complete engine”) 

in section 1068.30 is missing a critical example in paragraph (2). OPEI notes its engines are not 

considered complete until final carburetor adjustments have been done to bring engine into 

proper emission and performance compliance. OPEI requests to add subparagraph (2)(vi) as 

follows: "(vi) An engine that has been assembled (except for final labeling) but has not 

undergone final carburetor or other tuning to bring it into compliance with manufacturer’s 

specifications and these standards.” 

For handheld engines, OPEI does not believe that “short blocks” are “replacement 

engines,” and they should not be tested and labeled as such. Their short block consists of the 

crankcase, cylinder and crankshaft assembly. The block cannot run until the cooling, ignition, 

intake, carburetor, fuel system and shrouding are put on. Manufacturers sell this block for 

rebuilding because the cost of the block is less than the cost of the repair. OPEI requests EPA 

add language that this provision does not apply to handheld engines. 

GM commented that they have considered the impacts of EPA’s starting proposal. 

Although the concept of what EPA intends to do is simple, it truly creates a very difficult 

position for GM, and they suspect their OEM customers as well. GM hoped that they can find a 

better alternative to accomplish EPA’s goals. 

GM noted that its current business model works something like this. GM has a portfolio 

of engines that they offer to their marine customers. All of the engines they offer are partial 

engines (and GM is the primary engine manufacturer per EPA’s definitions). These engines are 

not capable of running in the as shipped configurations. GM’s customers (Mercury, Volvo, 

Indmar, Flagship, Kodiak, PleasureCraft and Marine Power) need to do an extensive upfit to 

"dress" these engines for the final boatbuilder - these customers are the "secondary engine 

manufacturers." The value added by these customers is significant and includes intake and/or 

exhaust manifolds, fuel systems, accessory drive, cooling systems, engine controllers and wire 

harness, etc. In all cases, GM is not the Manufacturer of Record, the Secondary Engine 

Manufacturers are. 

The engines GM offers are based off automotive variants and may include some unique 

marine hardware. GM may make multiple variants (flavors) of the same engine to meet 

customer applications differences (ex: sterndrive vs. inboard). They note this does create a 

proliferation of engine assemblies they offer and their manufacturing plants / logistics operations 

need to deal with this proliferation - of course, at a cost. As an example, today (2008) GM builds 

5 variants of the 5.7L (350 cubic inch) marine engine. Key differences include: 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

 With vs. without intake manifold and fuel system

 Front ring gear (sterndrive) vs. Rear ring gear (inboard)

 Partial ignition system vs. no ignition system 

 Mechanical throttle body vs. Electronic throttle body 

Thus, GM’s engineering release and engine plant have 5 part numbers (P/N's) to deal with. An 

engine assembly P/N is required for each unique parts list for the final shipped product. GM 

noted that because most of their marine customers use more than one type of engine from this 

5.7L family, this would create the need to create a very large number of labels - an extreme 

would be 5 engines x 7 customers = 35 labels. This would also require the GM system to replace 

the 5 engine assemblies with 35 engine assemblies - and that's just the 5.7L at one plant. GM 

continued to comment that obviously EPA can see the initial burden. This would significantly 

affect GM’s flexibility as today they can ship the same engine P/N to any of the customers who 

order that particular part number. This could be compounded more as the customers may sell 

globally (GM doesn't know if the engine is for sale in US or exported). Some engines may be 

used by their customers for their service needs. 

GM requested EPA to consider an option. They referenced some of EPA’s initial 

verbiage: "Manufacturers may introduce into US commerce, partially complete engines as 

described in this section if they have a written request for such engines from a secondary engine 

manufacturer that has certified the engine and will finish the engine assembly." GM questions 

whether this could be interpreted that if a secondary engine manufacturer requests (via purchase 

order) to procure an engine from a primary engine manufacturer a specific P/N - then this would 

be sufficient to meet EPA’s needs. GM noted that the engine will have engine P/N and broadcast 

codes, as well as information on the bill of lading where the engines come from. The secondary 

engine manufacturer could possibly also include in the PO any references as to engine family 

and certification intents. GM commented that EPA needs to discuss this issue with a broader 

group of affected companies. 

EMA commented on draft regulatory language allowing the movement of partially 

complete engines between different locations of the same parent company to affirm the principle 

and request that we clarify that current business practices are not required to change substantially 

and additional product identification or labeling are not required. 

EMA also suggested that the regulations allow engine manufacturers to ship partially 

complete engines before a Certificate of Conformity is approved. This may also be covered by 

the manufacturer-owned exemption and/or test exemption. 

In later comments, GM emphasized that they wanted to avoid labeling partially complete 

engines or, if labels are needed, to be sure that GM’s label is generic enough that they would not 

need to identify the destination or a valid engine family name on the label. Putting the receiving 

company’s name and address on the bill of lading is acceptable, but the bill of lading should not 

need engine family names. GM also objected to any provision that would put them in a position 

of ensuring that secondary engine manufacturers have a valid certification or exemption that 

allows them to receive shipment of partially complete engines. In addition, GM raised questions 

about how the regulations would allow for shipping engines for which the secondary engine 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

manufacturer has an exemption (testing, replacement, etc.), and for secondary engine 

manufacturers to ship engines to each other (such as for managing excess inventory). 

The Industrial Truck Association asked for clarification regarding engines that qualify for 

the manufacturer-owned exemption or the test exemption. They especially wanted to know how 

to apply the provisions of §1068.262 for engines that are exempt for other reasons. 

IMPCO noted that in certain cases, the equipment manufacturer purchases the engine and 

aftertreatment. This is effectively a pass through where they charge for the fuel system and 

installation, but are neither involved with the acquisition nor do they factor the cost of the engine 

or aftertreatment directly into the cost of the certified engine. Given that these are not test 

engines, they are not the certificate holder, and they will never be the certificate holder, IMPCO 

question how the equipment manufacturer would acquire these engines from the engine 

manufacturer. Also, the regulation should not require the manufacturer to state unconditionally 

that engines will comply with applicable regulations in their final configuration. As with § 

1068.261(j), the certifying manufacturer cannot be held liable for engines that are not in their 

final configuration when installed in the equipment, unless the certifying manufacturer was in 

some way negligent when it comes to specifying part numbers, installation instructions, etc. 

Allow the manufacturers to include qualifying language in their statement to recognize the 

equipment manufacturers’ need to follow installation instructions. 

IMPCO further commented that the proposed language related to revoking the exemption 

seems to allow EPA to revoke the exemption for the secondary engine manufacturer in its 

entirety. Therefore, IMPCO questioned whether EPA would have the authority to stop shipment 

of all GM engines to IMPCO, even if the noncompliance only occurred with one engine family. 

Given the liability placed on IMPCO for items that are outside of its control, IMPCO commented 

that EPA should have to prove the noncompliance on an engine family-specific basis. They 

believe this paragraph is too general and too far-reaching. Finally, IMPCO questioned what it 

means to say: "if that manufacturer sells engines that are not in a certified configuration". 

IMPCO noted that when engines are shipped without aftertreatment or other components, they 

are all "not in a certified configuration." 

1-43 
Chapter 1: Rulemaking Process and Cross-Program Issues 

Letters: 

Commenter Document # 

ISMA 0671 

IMPCO 0692 

MIC 0701 

Arctic Cat 0709 

NACOO 0714 

ECO 0712 

California ARB 0682 

OPEI 0675 

EMA 0691 

GM 0747 

EMA 0809 

GM 0787 

Industrial Truck Association 0800 

IMPCO 0812 

Our Response: 

At the time of the proposal, it became clear that manufacturers had somewhat varying 

interpretations of regulatory provisions related to partially complete engines. To the extent that 

manufacturers took the view that partially complete engines were not subject to emission 

standards, we understand that our proposed language to clarify the definition of “engine” would 

be a very meaningful clarification regarding the scope of EPA regulations. We believe it would 

be reasonable to consider the proposed definition (or a variation of it) to be the proper 

interpretation of regulatory requirements that were adopted earlier. However, we understand that 

manufacturers may not have been operating with that understanding. The proposal included a 

description of the concerns that led us to make this change, in particular the need to address the 

prevailing practice of shipping short blocks and long blocks to secondary engine manufacturers 

for certification as Marine SI engines and to address the increasing occurrence of noncompliant 

imported engines. 

We believe it is both necessary and appropriate to finalize the new definitions in this 

rulemaking. We received extensive input from a wide range of manufacturers during and after 

the public comment period on these issues, and have provided updated draft regulatory language 

to manufacturers representing other industry sectors. While the clarified scope of the regulation 

is broader than some manufacturers have understood to be the case previously, we have been 

careful to include exemption provisions to avoid unwarranted disruption of a wide range of 

legitimate business practices related to assembling and distributing engines. 

We agree with the manufacturers’ comments that the proposed definition of “engine” 

(block plus one attached component) was too broad. In particular, the first attached components 

may be dowels, pins, bushings, or plugs, none of which are fundamental to initiating the engineassembly process. Discussions led us to conclude that installation of the crankshaft serves as a 

clear, objective, and fundamental point in the production process that can be considered as the 

time when the engine block becomes an engine (when the engine is “born”). As a result, we will 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

consider engines subject to standards in any case where an engine block has an installed 

crankshaft, whether or not there are any additional components attached or assembled. This 

means that each one of these “engines” that is introduced into U.S. commerce needs to be 

covered by a valid certificate of conformity or an exemption (temporary or permanent). This 

approach applies equally to handheld engines, locomotive engines, and everything in between. 

We note in the definition that there are two types of engines—complete and partially 

complete engines. This is intended to allow for the situation where special exemption provisions 

apply for engines that are not yet in a certified configuration. Engines needing carburetor 

adjustments represent one possible example of that; however, this does not change the fact that 

we find it necessary to consider these partially complete engines to be subject to standards. See 

the discussion below regarding date of manufacture for further discussion of issues related to the 

flow of products and stages of assembly. 

We agree with the commenter that fully operational engines intended for installation in a 

recreational vehicle should be considered partially complete engines under the regulation. The 

rulemaking changes clarify these relationships and add a variety of oversight provisions (such as 

labeling, consistent with what was recommended) to prevent circumvention of the regulations. 

The provisions currently in §1068.330 are being expanded and codified in §1068.262. We 

believe this approach should be a minor change from current practice for companies currently 

buying engines for installation in their certified recreational vehicles. Nevertheless, we 

understand that manufacturers may need time to adapt their ordering and shipping practices to 

follow these new requirements. The definition of engine and the corresponding provisions 

related to partially complete engines take effect immediately once the final rule is effective. We 

are therefore specifying in §1068.40 that manufacturers may have up to 12 months to comply 

with new requirements. In the case of §1068.262, we are giving advance approval for waiving 

the documentation and tracking requirements related to partially complete engines. 

For the particular question about certificate holders shipping a partially complete engine 

from one plant to a different plant within the company, we address this in §1068.260 by 

specifying simply that manufacturers should notify us in their application for certification that 

they will be shipping these partially complete engines to another of their facilities. An approved 

certification represents an approval of the exemption that would allow for this transaction. No 

labeling or additional recordkeeping requirements apply. We learned that some companies rely 

on third-party companies to arrange for inventory and transport of engines even if they are 

shipping the engines between two of their own facilities. Sometimes this even involves 

transferring ownership of the engines to the other company. We chose to address this by adding 

a provision allowing for third-party companies to be involved in these engine shipments, as long 

as the certifying manufacturer demonstrates that the engines will be transported only according 

to its specifications. These provisions are intended to allow manufacturers to continue current 

practices, but we would not agree that manufacturers should be able to continue their current 

practices if they do not conform to these minimal requirements. Since the certificate-holder 

controls these engines at all times, there is no need for labeling or other identification beyond 

what the manufacturer would do for its normal business practice. 

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We have made some revisions to the exemption provisions in §1068.262 for shipping 

engines to secondary engine manufacturers that certify the engines. First, we specify that the 

documentation must identify a valid engine family name for the particular engine model. The 

secondary engine manufacturer would simply pass along this information when ordering the 

engine. The family name could represent a marine, industrial, or stationary application. The 

shipped engines would not all need to be built up to match the given engine family. For 

example, the secondary engine manufacturer could provide a valid family name for an order of 

4.3-liter engines, then build those engines to be covered by that certificate, or any other 

certificate. These engines could also be covered by an exemption (for export, for example). 

Such an exemption must be approved before the original engine manufacturer may ship engines 

under the provisions of §1068.262. Second, we specify that the removable label may be 

simplified to include only the shipping manufacturer’s name, a statement that the engine is being 

shipped to the certifying company, and a reference to the bill of lading. This allows the shipping 

engine manufacturer to make a universal label that would apply for all the engines it produces 

and ships under these provisions. Third, we are allowing manufacturers to apply a single label to 

engines that are packaged together. For example, if 30 Small SI engines are shipped in a palletmounted box, the manufacturer may label the box instead of labeling the engines individually. 

Fourth, we are including provisions allowing manufacturers to ship engines to secondary engine 

manufacturers while an application for certification is pending. This would allow secondary 

engine manufacturers to start producing engines after sending an application for certification. 

This is similar to what we allow for other manufacturers; see Section 1.5.1 for general provisions 

that apply for these early-production engines. Fifth, we have revised the requirement for 

secondary engine manufacturers to make an unconditional statement of compliance. The revised 

statement attests that the manufacturer has distributed engines that conformed to the regulations, 

rather than attesting that the engines in the final configuration will be compliant. This focuses 

the secondary engine manufacturer’s statement on the activities it can control. Sixth, we have 

revised the regulation to specify that it is a violation "if that manufacturer sells engines that are 

not in a certified configuration in violation of the regulations.” This avoids the confusion that 

might arise from the provisions related to selling engines without aftertreatment devices under 

the delegated-assembly provisions. 

The final rule does not include a requirement for original manufacturers to include engine 

family information on the engine label or on the bill of lading. We believe the documentation 

provisions related to ordering the engines and the requirement to ship the engines directly to the 

secondary engine manufacturer should be sufficient to ensure that engines reach a certified 

configuration before reaching the ultimate purchaser. However, this reduced information on the 

label requires that we specify that the original manufacturer assumes some responsibility for 

ensuring the validity of the information specified by the secondary engine manufacturer. 

Accordingly, we specify that we may void the original engine manufacturer’s exemption if the 

engines are shipped to the wrong destination or if engines are not properly labeled. 

The language describing how EPA might revoke the exemption generally applies to a 

secondary engine manufacturer’s engine family, but we clearly should be able to void or revoke 

an exemption more narrowly or more broadly if available information allows us to identify how 

specific the violation is. For example, we may void or revoke the exemption with respect to a 

particular engine model or for all engine models shipped to the secondary engine manufacturer, 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

depending on whether or not the violation is unique to a particular engine model. We may also 

void or revoke the exemption from the original engine manufacturer with respect to a single 

secondary engine manufacturer or all affected secondary engine manufacturers, depending on 

whether or not the violation is unique to a particular secondary engine manufacturer. 

We believe the final regulation and the guidance contained in rulemaking documents 

provides sufficient guidance to implement the new provisions. We will expect to interact 

extensively with companies as they follow these requirements and will be prepared to publish 

any necessary clarifications as the need arises. In particular, our understanding is that most of 

the exemption provisions related to partially complete engines are temporary, which means that 

the normal requirements (production-line testing, warranty, etc.) will all apply at a later point in 

the assembly and distribution process. The provisions for handling short blocks as replacement 

engines are permanent exemptions, but this is consistent with the way we have handled 

exemptions for complete replacement engines in the past. 

Note that we are adding a new §1048.601(b) to describe how the replacement-engine 

provisions of § 1068.240 apply for engines subject to part 1048 in conjunction with the 

secondary engine manufacturer provisions in § 1068.262. For cases in which the secondary 

engine manufacturer completes assembly of the engine, these provisions apply as written. If the 

secondary engine manufacturer arranges for a third party to complete engine assembly, some 

additional provisions apply. Most significantly, the ultimate purchaser must purchase (or 

otherwise order) the replacement engine from the secondary engine manufacturer, and the 

secondary engine manufacturer and engine assembler are both responsible if the engine is 

installed in new equipment or otherwise violates the circumvention provisions of § 1068.240. 

1.5.2 Definition of “date of manufacture” and issues related to “model year” 

What Commenters Said: 

EMA commented that EPA is proposing a significant regulatory change – not a 

clarification – that would define an engine’s date of manufacture based on when the engine is 

capable of running or on when an incomplete engine is imported to the U.S. This significant 

change is both unwarranted and misguided. EPA’s proposed change will alter the way in which 

manufacturers currently operate, will impose significant costs and administrative burdens, and 

will not provide any emission benefit. Indeed, EPA has not identified any “problem” that it is 

attempting to solve. The fact of the matter is that EPA’s new definition will create problems. 

EMA continued commenting that under EPA’s rules, a manufacturer on a calendar year 

model year (which is the vast majority of manufacturers) cannot produce an engine for the 

current model year after December 31 of that model year. However, EPA’s proposed new rules 

would require the manufacturer that begins production of an engine in one model year to meet 

the regulatory requirements of the next model year (when the engine can actually run or when 

the incomplete engine is imported). That is wrong and unfair. It is obvious that, as a practical 

matter, an engine built on December 31st could not run or would not be imported until January 

1st. So, the December 31st engine would either have to be built to the next model year’s 

standards, or it could not be sold. It is just as obvious that such a scenario could occur for 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

engines built on December 30th, and probably for all of December, and, indeed, for engines built 

even earlier in that model year. The nature of the manufacturing process, exacerbated by the 

location of engine plants throughout the world and the non-integrated nature of the industry, 

makes EPA’s proposed new date of manufacture definition not only impractical, but likely 

impossible. 

EMA commented that manufacturers cannot live with a rule that prohibits them from 

assigning the date of manufacture at the point within the engine assembly process that is relevant 

to their specific manufacturing workflow. The assignment process established for a given 

manufacturing facility does not (and should not) change from day to day or from the beginning 

to the end of a model year. For products that are imported as incomplete engines, the date of 

manufacture likewise is determined and assigned during the manufacturing process - - a timing 

and process that is independent of shipment and importation. 

EMA continued that to a large degree, EPA’s proposed change seems to be a “solution in 

search of a problem.” Certainly, for those model years where there is no change in standards 

(i.e. most model years), the potential for somehow “gaming” the system around defining the date 

of manufacture simply does not exist. But, even for those model years in which there is a change 

in standards, any potential for “gaming” can be eliminated by EPA simply requiring that 

whatever process and procedure the manufacturer uses for establishing date of manufacture 

remain constant for an engine family throughout all of its model years. 

Finally, EMA noted that engine manufacturers are required to control inventory of either 

in-process engines, or incomplete engines being imported, to normal levels through both EPA 

anti-stockpiling requirements and also normal business practices. Accordingly, manufacturers 

should be allowed to maintain their current production process for the determination of the 

engine date of manufacture. 

OPEI commented that the definition for Date of Manufacture in section 1068.30 is too 

obscure. Paragraph (1)(i) of the definition has a very narrow interpretation. An engine being 

able to run is different than an engine set to run properly for emission and performance. OPEI 

suggests this wording be revised as follows: “The date on which the engine is assembled and 

adjusted to the point of being able to properly run for compliance to these standards.” 

OPEI also commented that EPA should clarify section 1060.201. The certificate of 

conformity will list an effective date (signature date). The manufacturer may not introduce into 

commerce before this date but may produce equipment/engines prior to the effective date. 

California ARB recommended that procedures be adopted to prevent any stockpiling of 

engines that could be used to circumvent the regulations. 

OPEI/EMA suggested that EPA clarify the allowance for equipment manufacturers to use 

up inventories of previous MY engines, adding an allowance for engine manufacturers to sell 

engines that they had built in the previous MY. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

IMPCO commented that §1068.103(c) appropriately allows for production of engines 

while an application for certification is pending, but the regulation should prohibit introduction 

into U.S. commerce only rather than also prohibiting the selling and offering to sell such engines. 

Manufacturers also raised a variety of issues related to our proposal to adopt certain 

restrictions on naming an engine’s model year for importation, as described in Section 2.10.3. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

California ARB 0682 

IMPCO 0812 

Our Response: 

Until now, the regulations have not specified the point in the assembly process that 

should serve as the basis for establishing an engine’s date of manufacture. For the large majority 

of engines, this is not an issue, since total assembly time from start to finish is measured in hours 

or perhaps days. As a result, it is relatively uncommon for there to be any uncertainty regarding 

an engine’s date of manufacture for purposes of deciding which standards apply. Nevertheless, 

we have learned that there are widely diverging practices for establishing an engine’s date of 

manufacture, which means there is a different effective date of new emission standards for 

different manufacturers. This is especially of interest for larger engines, which are more likely to 

be assembled in multiple stages at different facilities. We believe it is important to establish a 

clear requirement in this regard to avoid ambiguity and different interpretations. A consistent 

approach preserves a level playing field and may prevent some manufacturers from manipulating 

their build dates to circumvent the regulations. 

We expected that the proposed definition of “date of manufacture,” based on reaching a 

final, running configuration, was the most straightforward and logical interpretation. The 

comments received and the ensuing discussions made clear that this interpretation was not 

universally held. The diversity of views underscores the need for the regulations to establish a 

clear and uniform requirement. Once we are able to establish such a requirement, we believe 

there would be a “cost and burden” only for those companies that would otherwise be attempting 

to delay complying with new emission standards. Requiring only that manufacturers continue 

their normal business practice or maintain a consistent approach from year to year would not do 

enough to establish uniform and enforceable requirements related to the transition to new 

emission standards. 

However, we recognize the concern that manufacturers need a rather high degree of 

certainty regarding applicable emission standards when they initiate assembly of an engine. Any 

number of variables in the production process could affect how long it takes to finish building an 

engine. We therefore believe it is most appropriate to match up the definitions for “date of 

manufacture” and “engine” by specifying that an engine’s date of manufacture should be based 

on the date that the crankshaft is installed in the engine. This provides manufacturers with the 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

control they need to determine which emission standards apply when they start to build the 

engine. 

We are aware that secondary engine manufacturers may have inventory and assembly 

procedures that are not tied to the actual date of crankshaft installation by the original engine 

manufacturer. We are therefore specifying for this situation that the date of manufacture is 

generally the date the secondary engine manufacturer receives shipment of the partially complete 

engine. The manufacturer may alternatively specify a date of manufacture up to 30 days earlier 

as long as that date is not earlier than the date the crankshaft was actually installed in the engine. 

This puts the secondary engine manufacturer in a similar position relative to companies with sole 

responsibility for assembling complete engines, without placing unreasonable expectations on 

secondary engine manufacturers. 

Some manufacturers would be interested in naming a date of manufacture that is later 

than we specify in the regulation, as suggested in the comments. This may be for marketing 

purposes, managing inventories of engine components, or for other recordkeeping or productdevelopment reasons. There is no risk of manufacturers gaining an advantage of being subject to 

less stringent standards by delaying the date of manufacture for an engine, so we would have no 

objection to that. However, we limit the selection of date of manufacture to a later point in the 

assembly process. Selecting a date of manufacture after the end of the assembly process for an 

engine would raise concerns about the risk of manipulating emission credits for a given model 

year and about ensuring that engine assembly and dates of manufacture are always within the 

production period established for a given engine family, as described in the certificate of 

conformity or the manufacturer’s records. We see no legitimate reason to select a date of 

manufacture after completing assembly for an engine. 

This approach addresses manufacturers’ concerns for knowing which standards apply to 

an engine, but we are concerned that manufacturers could ramp up production of engine blocks 

with installed crankshafts as a method to delay compliance with new emission standards. EPA 

regulations have always included provisions describing limits on inventory and stockpiling 

practices for equipment manufacturers. The regulations until now have not clearly addressed 

issues related to stockpiling for engine manufacturers. We agree with the suggestion from 

commenters that anti-stockpiling provisions would be appropriate. The Clean Air Act 

contemplates the need for such provisions in §202(b)(3) where there is direction for EPA to 

consider establishing a definition of model year that prevents stockpiling. At the same time, we 

received other comments related to production periods and model year, leading us to adopt a 

collection of related provisions in §1068.103. 

The new text in §1068.103 includes three main provisions that are already in place for 

motor vehicles and heavy-duty highway engines in §§85.2304 and 85.2305. First, we are 

clarifying that the scope of a certificate of conformity may be limited to established engine 

models, production periods, or production facilities. Any such limits would be included in the 

manufacturer’s application for certification or in the certificate of conformity. Second, we are 

defining the limits on selecting production periods for purposes of establishing the model year. 

Third, we are clarifying that engine manufacturers may start producing engines after they submit 

an application for certification and before the certification is approved. This includes provisions 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

to address the manufacturers’ responsibility to ensure (1) that engines are not introduced into 

U.S. commerce or offered for sale until the certification is approved, (2) that all engines are 

assembled consistent with the certification, including any changes that may have come from the 

certification review process, and (3) that manufacturers make these early-production engines 

available for production-line testing or selective enforcement audits, as appropriate. 

In addition, we are adding provisions to establish limits on stockpiling for engine 

manufacturers. We are doing this by stating that manufacturers must use their normal inventory 

and assembly processes for initiating assembly of their engines. We include a clarifying 

expectation that we would expect normal assembly processes to involve no more than one week 

to complete engine assembly once the crankshaft is installed. We understand that assembly 

processes in some cases are more complicated, and that engine manufacturers may be unable to 

complete engine assembly in some cases based on delivery of certain components. To put some 

boundaries on these exceptional situations, the regulation specifies a presumption that the engine 

manufacturer has violated the stockpiling prohibition if engine assembly is completed more than 

30 days after the end of the model year. This presumption date is 60 days after the end of the 

model year for engines with per-cylinder displacement above 2.5 liters. This generally 

distinguishes engines that may have relatively high sales volumes (including heavy-duty 

highway engines) from bigger engines that are only sold in lower sales volumes. 

Two additional provisions are intended to minimize potential burden and disruption 

related to transitioning to new model years. We specify that the restrictions related to date of 

manufacture and model year do not apply if there is no change in emission standards for the 

coming model year. We are also including hardship provisions to allow manufacturers to request 

approval to extend the final assembly deadline for their engines if circumstances outside their 

control prevent them from completing engine assembly in time. We would approve such a 

request only if the manufacturer could not have avoided the situation and took all possible steps 

to minimize the extent of the delay. 

Note that we are also clarifying in the standard-setting parts that the certificate is valid 

starting with the indicated effective date, but that it is not valid for any production after 

December 31 of the model year for which it is issued. We are also adopting a provision to 

preclude issuance of certificates after December 31 of a given model year. This will avoid a 

situation in which a manufacturer receives certification after it is no longer valid for further 

production. 

Finally, note that we are adopting a provision specifying that imported products may not 

have a model year more than one year earlier than the calendar year of importation, as described 

in Section 2.10.3. We proposed this in part 1054 for Small SI engines and requested comment 

on including it in part 1068 for all nonroad engines. Manufacturers generally had no objection to 

expanding the scope of this provision to other categories of nonroad engines. We are therefore 

adopting this provision in §1068.360. 

We understand Impco’s interest in making arrangements to sell engines once they have 

submitted an application for certification for a given engine family. However, making such 

commitments to supply products before the certification is approved would put EPA in an 

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difficult position if the application included significant shortcomings. If the manufacturer would 

need to do further testing, modify the engine design, or make other changes to adequately 

demonstrate compliance with applicable requirements, there could be substantial delays in the 

certification process. During this time, the manufacturer would likely insist on accelerating the 

approval because of their premature business commitments. We believe this could interfere with 

the normal review process. Furthermore, the Clean Air Act prohibits selling or offering to sell 

engines that are not yet covered by a certificate of conformity, so it is not clear how we could 

create such an allowance that is consistent with the Act. 

Finally, we note that we are adding a new paragraph to §1054.601 to clarify how engine 

manufacturers can sell engines after the end of the model year. This text does not change the 

prohibition in 40 CFR 1068.103(f) against engine manufacturers deviating from normal 

production and inventory practices to stockpile engines with a date of manufacture before new or 

changed emission standards take effect. It does add a requirement that manufacturers get our 

prior approval for model years in which emission standards change if their normal practice for 

producing engines includes maintaining engines in inventory for some engine families for more 

than 12 months. Manufacturers would be required to show that this is necessary and consistent 

with their normal business practice. They would also be required to include relevant inventory 

and production records from the preceding eight years. 

1.5.3 Retailer liability 

What Commenters Said: 

OPEI shares EPA's concerns that many U.S. importers, distributors and retailers currently 

do not fully appreciate that they can be found responsible and liable for selling non-compliant 

small engines. Section 203(a) of the CAA prohibits any "person" "causing" the importation of 

non-compliant or uncertified engines or vehicles. U.S. retailers that purchase non-compliant or 

uncertified engines from an importer may be found responsible for "causing" the importation of 

illegal products. The final regulations and preamble discussion should make it clear that retailers 

selling non-compliant products may be subject to the enforcement provisions set forth in 

Sections 113, 204 and 205 of the Clean Air Act. 

Analogous case law holds that retailers act as de facto “importers” if they are inducing 

and causing the importation. See Terry Haggerty Tire Co. v. United States, 899 F.2d 1199 at 

1200 (Fed. Cir. 1990). In this case, the Court found that a tire retailer, who merely purchased 

goods from a Canadian company, but did not arrange for or participate in the shipment or 

importation of the goods, had caused the sale sufficient to be held as the importer. 

In California, retailers and distributors, as well as equipment manufacturers, are 

potentially “strictly liable” for offering for sale or selling non-compliant small-engines or lawn 

and garden equipment. In assessing liability, California ARB looks at each individual case to 

determine which parties were principally at fault in causing the violation. California ARB’s 

general enforcement policy has been to not impose penalties on innocent manufacturers or 

retailers who undertook “reasonable prudent precautions” to ensure they are selling certified and 

compliant products. However, if, for example, a retailer purchased products that are less than 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

half of the purchase price of the normal, low-end range of a certain category, California ARB 

will question whether that retailer failed to take any precautions whatsoever, and should have 

known he was buying suspect, non-compliant products. The California ARB enforcement 

approach has provided a much-stronger deterrent than the current EPA program vis-à-vis the 

offering for sale of non-compliant products. 

In response to EPA’s concerns about duplicative certifications being filed, even the 

equipment manufacturers, retailers and distributors that have received substantial penalties under 

California ARB settlements are not re-testing or re-certifying products with an emission label. 

However, these retailers are incentivized to buy compliant products from reputable, rather than 

“fly by night” companies, and to contractually require their suppliers to sell only certified and 

emission-compliant products, subject to indemnifications for any violations. EPA should 

develop policies that will achieve these same incentives in the national marketplace. OPEI urges 

EPA to pull ahead and make effective in 2007 the regulatory clarifications that retailers and 

distributors that “cause” a prohibited act are potentially liable parties. 

In addition, various OPEI member companies sent in separate letters encouraging us to 

take a position consistent with the OPEI recommendations described above. 

Letters: 

Commenter Document # 

OPEI 0675 

Stihl 0767 

Honda 0767 

John Deere 0767 

Briggs & Stratton 0767 

Our Response: 

We agree with the suggestion from OPEI to include in the regulations a clear statement 

that we consider it a violation to cause someone to commit a prohibited act. The preamble to the 

final rule also describes the basis and context we would consider for evaluating possible 

“causation” violations. 

1.5.4 Defect reporting 

What Commenters Said: 

OPEI appreciates the changes for defect reporting and believes that the changes have 

leveled the requirements between large and small volume manufacturers with no negative impact 

on the environment. OPEI also agrees with the effective date of 2009 for Small SI. 

MIC commented that § 1068.501(a)(1)(ii) should be modified to delete the reference to 

“connectors” for which no permeation standards or test procedures have been defined. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

GE commented that EPA should not extend the tracking requirements for other nonroad 

engines regarding defect investigation and reporting to locomotives and locomotive engines but 

should instead retain the approach currently used under part 92. GE also restated detailed 

comments made during the recently finalized locomotive rulemaking. 

Letters: 

Commenter Document # 

GE 0679 

MIC 0701 

OPEI 0675 

Our Response: 

We disagree with the comment from MIC to eliminate fuel line connectors from the list 

of evaporative emission components subject to defect reporting. While we do not have separate 

emission standards for connectors, defective connectors have the potential to result in emissions 

just as significant as defective fuel lines. By including them on the list we are merely requiring 

that the manufacturer investigate defects when they become aware of them and report them to us. 

This is not an overly burdensome requirement. 

GE’s comments were addressed in the locomotive rulemaking by revising the reference 

to §1068.501 in 40 CFR 1033.601. 

1.5.5 Delegated assembly 

What Commenters Said: 

EMA commented, and as they have discussed their comments with EPA at length, that 

the existing delegated assembly provisions applicable to land-based nonroad engines are 

inadequate. Because they include a provision not found in any other mobile source regulation – 

the mandatory requirement to include the price of the aftertreatment with the price of the engine, 

they create a major economic penalty for manufacturers. By requiring the price of the 

aftertreatment to be included in the price of the engine, importers have to pay an import duty on 

the price of the aftertreatment even if the aftertreatment is manufactured in the United States. 

Similarly, for aftertreatment systems that are imported separately from the engine, the duty is 

paid twice. The proposed allowance for importers to segregate the cost of the separately shipped 

components to avoid duplicate duties is not acceptable and, in any event, is not within EPA’s 

regulatory authority. 

EMA continued to comment that it is not fair, appropriate or necessary for EPA to 

impose this requirement on land-based nonroad engines. In fact, EPA currently provides an 

option in the delegated assembly provisions applicable to heavy-duty on-highway engines. 

Manufacturers either can include the price of the aftertreatment with their engine, or they can opt 

to exclude the cost of the aftertreatment and meet certain audit requirements. EPA should 

finalize a similar provision for nonroad engines. In addition, nonroad engine manufacturers 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

should be provided with the delegated assembly flexibility being proposed for Small SI engine 

manufacturers associated with the sale of engines through distributors. 

EMA commented that both of the changes recommended above are needed and 

appropriate for land-based nonroad engines and can be implemented by EPA within the scope of 

the existing regulatory process. 

In response to draft regulations that address the concerns described above, EMA 

suggested clearer language stating that air filters are not subject to delegated-assembly 

requirements if they are not specified by part number in the manufacturer’s application for 

certification. 

EMA (0738) commented that we should include preamble language to clearly describe 

when air-intake systems are subject to delegated-assembly requirements. They also requested 

that we delay the labeling requirements associated with delegated assembly for heavy-duty 

highway engines until 2010. In addition, they requested that we not require manufacturers to 

investigate assembled engines after an initial, successful audit. 

IMPCO requested that we clarify what records would be appropriate for showing that 

parts were randomly collected to prepare for production-line testing with engines that participate 

in delegated assembly. They also objected to the requirement for the certifying manufacturer to 

get written confirmation that an equipment manufacturer has ordered the appropriate 

aftertreatment devices and to the inclusion of air filters in the delegated-assembly provisions. 

They believe these provisions are redundant with all the other requirements for documentation 

and verification. 

IMPCO commented that revoking the exemption should be narrowly related to the 

equipment manufacturer and engine family that were the subject of a violation. They also 

objected to the regulatory provision assigning liability for in-use compliance to the engine 

manufacturer, stating that it would be irrational to expect the engine manufacturer to be 

responsible for anything past delivery to the equipment manufacturer, assuming the auditing and 

other applicable provisions have been followed. 

EMD provided comments arguing against applying the proposed §1068.260 to 

locomotives. They also opposed applying §1068.260(b)(4) and (b)(6) to C2 marine engines. 

Letters: 

Commenter Document # 

EMD 0687 

EMA 0691 

EMA 0738 

EMA 0818 

IMPCO 0812 

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Our Response: 

It is important to begin by emphasizing that the delegated assembly provisions do not 

represent additional requirements, but rather are voluntary provisions intended as a flexibility to 

manufacturers. With respect to liability, we expect engine manufacturers to take appropriate 

“steps to ensure that all engines will be in a certified configuration when installed by the 

equipment manufacturer.” Manufacturers that do not believe they can effectively ensure that 

engines are in a certified configuration when installed by the equipment manufacturer should not 

use these delegated assembly provisions. We believe that holding engine manufacturers liable 

for the final assembly is the best way to ensure they take appropriate steps to prevent problems. 

We do not agree that pricing engines and aftertreatment together is an unreasonable 

requirement. In fact, it is not a regulatory requirement under the current program as much as a 

constraint on exercising an allowance to depart from regulatory requirements. If the pricing 

provisions are more burdensome than shipping engines with aftertreatment devices, then 

manufacturers could simply choose not to participate in delegated assembly. For those 

manufacturers wanting to pursue delegated assembly, we believe the pricing requirement is 

important in preventing vehicle or equipment manufacturers from being in a situation where they 

would gain a financial advantage by installing engines without the proper emission controls in 

place. We have confirmed with the U.S. Customs and Border Protection that inappropriate 

payment of import duties for components that are not shipped with a given engine can be 

avoided with documentation showing that the price of the engine includes a charge for 

components that are not included in that particular shipment. This could most easily be 

accomplished by itemizing the invoice to identify the value of the missing components relative to 

the value of the rest of the engine. The regulations now include these specific instructions 

regarding invoicing with respect to import duties. 

We understand that engine manufacturers have competing interests both to maintain the 

ability to arrange flexible assembly procedures and agreements, and to ensure that their engines 

are introduced into commerce only after being assembled in the certified configuration. We 

share those objectives and believe the regulations serve the purpose of creating a framework for 

balancing these different concerns. By applying these provisions in the regulations, 

manufacturers will not find themselves in a situation where competitiveness concerns cause them 

to take steps to reduce costs at the risk of producing noncompliant products. 

We agree with EMA, however, that it would be appropriate to apply the delegatedassembly framework for heavy-duty highway engines to other nonroad engines. The main 

difference between programs is the allowance for heavy-duty highway engines to rely either on 

the pricing strategy described above or on audits of vehicle manufacturers, but not necessarily 

both, to ensure that installed engines are in the certified configuration. While we are concerned 

about the incentive for vehicle and equipment manufacturers to gain a financial advantage if 

aftertreatment components are not priced together with the engine, we believe that requiring 

engine manufacturers to confirm that vehicle or equipment manufacturers have ordered the 

required aftertreatment components and to perform audits of vehicle or equipment manufacturers 

is generally sufficient to provide the proper assurances that engines are being properly assembled 

and installed. Conversely, we believe that pricing aftertreatment and engines together is a strong 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

enough assurance of proper assembly and installation procedures that audits are not always 

necessary as an additional oversight measure. We note that these provisions spell out a 

minimum level of oversight for engine manufacturers. There may be instances, such as a new 

relationship with a vehicle or equipment manufacturer or some other reason to have less 

confidence in proper assembly procedures, where the engine manufacturer would want or need to 

take extra steps to ensure that engines are assembled properly. 

We recognize the inconvenience of requiring engine manufacturers to obtain written 

confirmation that the equipment manufacturers have ordered aftertreatment components before 

shipping the engines. Thus, the final regulations only require this be done for the initial 

shipment. This will significantly limit the inconvenience, while ensuring that the equipment 

manufacturers understand their obligations before they start receiving engines. 

We believe there is a strong advantage in implementing requirements uniformly across all 

the engine programs, both for EPA and for manufacturers. Aside from the pricing and auditing 

requirements described above, we are making the following provisions part of the final program, 

which were part of one or both of the separate programs in parts 85 and 1068: 

• Auditing rates are generally set at four vehicle or equipment manufacturers per year, or 

enough to rotate through all the equipment manufacturers over a four-year period, 

whichever is less. A reduced rate may apply after several years of successful 

implementation of these requirements. 

• We are continuing the approach already adopted to provide for a streamlined 

demonstration for integrated manufacturers where the auditing would effectively be an 

internal practice. 

In addition, we are including the following provisions in the unified approach to 

delegated assembly that were part of the proposal for Small SI engines: 

• Distributors may participate in delegated assembly, but only to the extent that they act as 

equipment manufacturers, adding aftertreatment devices before shipping the engines to 

vehicle or equipment manufacturers. Allowing distributors to further delegate engine 

assembly to another set of companies raises fundamental questions about the ability of 

engine manufacturers to adequately ensure proper final assembly of their engines. We 

are making a temporary allowance for this for Small SI engines to accommodate the 

transitional provisions allowing equipment manufacturers to gradually work toward 

making Phase 3 products. 

• If engine manufacturers design their air-intake systems such that they depend on specific 

parts (identifiable by part number) to achieve proper air flow through the engine, that 

raises concerns that are similar to aftertreatment devices. In fact, we are currently 

pursuing an enforcement case where an equipment manufacturer did not follow the 

engine manufacturer’s directions to use a specific air filter. We are specifying that air 

filters identified by part number must be included in delegated assembly, though we 

require audits related to air filters only if audits are already occurring for exhaust 

systems. If manufacturers specify intake air systems by performance parameters such as 

maximum pressure drop across the air filter, the delegated-assembly provisions do not 

apply. This is similar to the way we have treated exhaust components for systems not 

requiring exhaust aftertreatment. See §1068.260(a). 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

• Vehicle or equipment manufacturers submitting annual affidavits must include a count of 

aftertreatment devices received to verify that there were enough of the right models of 

aftertreatment devices for the number of engines involved. 

• Engines need to be labeled to identify their status as delegated-assembly engines, either 

with a removable label or with “Delegated Assembly” noted on the engine’s permanent 

label. This ensures that engines will not be introduced into commerce without an 

indication of their status relative to the certified configuration. 

• Engine manufacturers must confirm that vehicle or equipment manufacturers have 

ordered aftertreatment devices corresponding to an engine order, but this confirmation is 

limited to the initial shipment of engines for a new certification and may occur up to 30 

days after the engines have been ordered. 

• For engines subject to requirements for production-line testing or selective enforcement 

audits, we specify that aftertreatment components must be randomly procured. We agree 

with the suggestion in the comments to broaden the allowance for randomly procuring 

components. As long as manufacturers use a method to randomly select components that 

are appropriate for the particular engine configuration, these components may come from 

any point in the normal distribution chain. 

We agree that the labeling requirements are new for heavy-duty highway engines and are 

therefore allowing until the 2010 model year for manufacturers to start meeting requirements for 

these engines. 

We agree that delegated assembly provisions do not apply for components that are not 

emission-related. See §1068.260(b). However, we disagree with IMPCO’s comment to exclude 

air filters. Nevertheless, §1068.261(e) describes a less burdensome approach for air filters. We 

are including preamble language to further clarify the distinction between intake systems that are 

specified in the application for certification by part number or by performance specification. 

We believe it is not appropriate for the regulations to specify that a single audit showing 

proper assembly procedures is a sufficient basis for discontinuing future audits. We are 

concerned that engine and equipment manufacturers must have an extended period of complying 

with these provisions with significant communication, oversight, and verification to ensure that 

engines are being assembled properly. The regulations in all our programs (proposed and 

adopted) have specified a reduced auditing schedule only after cycling through two four-year 

auditing periods. We continue to believe this is appropriate for the universal program. 

With respect to production-line testing, we would expect manufacturers to need to keep 

simple records describing the algorithm used to make the selection. 

We have modified parts 89 and 94 to allow manufacturers to use the delegated-assembly 

provisions and other provisions related to partially complete engines for land-based nonroad 

diesel engines and marine diesel engines. It is not likely that these engines will be using 

aftertreatment devices to meet current standards, but there may be circumstances where this may 

apply. The new regulatory provisions also clarify exemptions and special provisions that apply, 

for example, for within-company shipments between facilities and for shipping engines without 

certain engine components. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

We acknowledge that manufacturing processes and regulatory requirements for 

locomotives and locomotive engines warrant special treatment with respect to shipment and 

assembly of aftertreatment devices. We have therefore adopted such provisions in 40 CFR part 

1033 that apply specifically to locomotives instead of the delegated assembly provisions we are 

adopting in §1068.261. 

1.5.6 Engine rebuilding 

What Commenters Said: 

Cummins requested clarification in the rebuild requirements of Parts 89 and 1039 via Part 

1068 that a rebuilt engine may be used to replace any equivalent engine regardless of model 

year. (i.e. a rebuilt Tier 1 engine may replace a TPEM engine or an AB&T engine (assuming 

they are identical) of a later model year. They noted that this issue has been raised within 

Cummins particularly with large engines (>560kW) where there are often times fleets of vehicles 

that are supported with spare engines owned by either the mine owner or by a Cummins 

distributor. At the time of engine failure, or rebuild, Cummins believes it is acceptable to replace 

engines on a "like-for-like" basis regardless of model year. Because of TPEM and AB&T 

flexibility, the use of the term model year in 1068.120 could be interpreted to not allow this likefor-like replacement. Therefore, Cummins requested a revision to the regulatory language for 

§1068.120 as noted below. Cummins also commented on §89.1003 and §1068.240, as noted 

below, and commented that those changes may not be needed given that those sections deal with 

new replacement engines. However, Cummins commented that they would like EPA to consider 

those changes as well. 

1068.120 : Rebuilding 

(f) If the rebuilt engine replaces another certified engine in a piece of equipment, you 

must rebuild it to a certified configuration of the same model year or Tier level as, or a 

later model year or Tier level than, the engine you are replacing. In circumstances 

involving a TPEM engine or an engine certified to a later Tier level using AB&T credits, 

the engine is considered interchangeable with a previous Tier engine for the purpose of 

installation in a piece of equipment as long as the engine is identical in all material 

respects to the engine being replaced. 

89.1003(b)(7) : New Replacement Engines 

(v) Where the replacement engine is intended to replace an engine that is certified to 

emission standards that are less stringent than those in effect when the replacement 

engine is built, the replacement engine shall be identical in all material respects to a 

certified configuration of the same or later model year or Tier level as the engine being 

replaced. In circumstances involving a TPEM engine or an engine certified to a later Tier 

level using AB&T credits, the engine is considered interchangeable with a previous Tier 

engine for the purpose of installation in a piece of equipment as long as the engine is 

identical in all material respects to the engine being replaced.. 

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1068.240(a) 

(5) You make the replacement engine in a configuration identical in all material respects 

to the engine being replaced (or that of another certified engine of the same or later model 

year). This requirement applies only if the old engine was certified to emission standards 

less stringent than those in effect when you produce the replacement engine. In 

circumstances involving a TPEM engine or an engine certified to a later Tier level using 

AB&T credits, the engine is considered interchangeable with a previous Tier engine for 

the purpose of installation in a piece of equipment as long as the engine is identical in all 

material respects to the engine being replaced. 

California ARB encourages EPA to address the status of remanufactured engines as being 

fully subject to the requirements for rebuilt engines in 40 CFR 1068.120, and to adopt labeling 

requirements for rebuilt engines similar to those in California’s Off-Road Diesel Regulation at 

13 CCR 2423(l). 

OPEI commented that their units do not have hour meters and an exact hour of use is not 

always possible. OPEI suggests language in section 1068.120(j)(1) be reworded to indicate 

approximate hours of use or in-use service time and method used to determine such estimates. 

EMA commented that the proposed provisions regarding engine rebuilding are acceptable 

but incomplete because they do not adequately address the difference between model year 

requirements and emission standard requirements. In the final rule EPA should clarify that an 

engine that is rebuilt may be used to replace any equivalent engine model regardless of the model 

year of the equipment. 

EMA recommended that we include a definition for “rebuilding.” 

OPEI believes EPA may be creating burdens on industry segments unaware of this rule 

and incapable of providing the amount of burdensome records required by this part. OPEI 

proposes EPA exempt engines/equipment subject to part 1054 from this provision. 

EMA commented that Small SI engines are significantly different than larger engines 

currently regulated under §1068.120. The listed requirements must either be excluded for Small 

SI engines or modified to allow the appropriate requirements for Small SI engines. 

Letters: 

Commenter Document # 

Cummins 0719 

California ARB 0682 

OPEI 0675 

EMA 0691 

EMA 0808 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

We agree with Cummins that the regulations should more carefully address rebuild 

requirements for special cases such as spare engines for maintaining a fleet, engines with Family 

Emission Limits above or below the standards, and engines produced under the Transition 

Program for Equipment Manufacturers. We have revised the regulations in §1068.120(f) to 

describe how the rebuilding provisions apply under several such scenarios, consistent with the 

approach recommended by Cummins. 

We agree with California ARB that remanufactured engines are generally subject to 

rebuilding requirements. We note, however, that remanufactured engines might become “new 

engines,” for example, if they are installed in new vehicles or equipment. In this case they would 

need to be certified before being introduced into commerce like any other new engine. 

Remanufactured engines that qualify as “new engines” are typically used as replacement 

engines. As such the provisions for the replacement-engine exemption in §1068.240 would 

apply, including the labeling requirements, as described in Section 1.5.7. 

We agree that the rebuilding provisions should acknowledge that approximate service 

hours (or miles) are adequate for engines without hour meters (or odometers) and have changed 

the regulation accordingly. 

We agree with EMA that a rebuilt engine may be used to replace any equivalent engine 

model regardless of the model year of the equipment and have changed the regulation 

accordingly. 

The current regulations include language describing what qualifies (and does not qualify) 

as rebuilding. Absent any specific recommendations, we believe it is not appropriate to more 

carefully define what constitutes engine rebuilding. Moreover, the same requirements (except 

recordkeeping) generally apply for routine maintenance as for rebuilding so we believe it is also 

not necessary to add this kind of clarification. 

We understand the concerns raised by OPEI for small spark-ignition engines. Engine 

repairs for a single-cylinder engine might involve replacing the piston or piston rings. This 

should still be done such that an engine remains in its certified configuration, but we agree that 

someone might easily do this maintenance without realizing that they have triggered a regulatory 

requirement. This is especially true for lawn and garden applications, but the same dynamic 

applies for small outboard engines and small engines used with recreational vehicles. We are 

therefore revising the regulation to waive the recordkeeping requirements for spark-ignition 

engines below 225 cc. Larger engines are much more commonly used in commercial 

applications where operators and repair professionals would be more likely to have maintenance 

and rebuilding practices that resemble those for diesel engines or for larger spark-ignition 

engines. 

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1.5.7 Replacement engines 

What Commenters Said: 

EMA commented that the existing replacement engine exemption was unworkable for 

partially complete engines. They recommended a separate replacement-engine exemption for 

partially complete engines, including any engine assembly in which some components necessary 

for engine operation were missing. They recommended that such engines could be used for 

replacement purposes with no restriction other than labeling the engines to identify them as 

“service use only”. They also recommended that we define the terms “replacement engine” and 

“destroyed.” 

In response to draft regulatory language describing an allowance for a limited number of 

partially complete replacement engines without requiring the usual tracking, demonstration, 

recordkeeping, etc., EMA commented that these provisions should also apply for engines 

between 2.5 and 7 liters per cylinder, and that they should apply for marine diesel engines. They 

also noted that the labeling requirements in §1068.265 appeared to be in conflict with the 

labeling specifications in §1068.240. 

ECO responded to questions about industry practices for replacement engines. They 

described Marine SI manufacturers as sending long blocks out only on an as-needed basis. There 

are some marinas willing to pay the flooring charges to keep blocks immediately available, but it 

sounds like this is probably the exception to the rule. Regardless, ECO noted that for the small 

manufacturers that might sell 200-300 engines per year, the 0.5% allowance is only 1 to 1.5 

engines. ECO commented that this is not much. Based on input from Kodiak Marine Parts, 

ECO commented that 1% would probably be better, as it would give a little extra flexibility. 

IMPCO asked whether §1068.240 applies only to engines that are specifically built as 

replacement engines, or to all engines that might be used as replacement engines, and noted that 

they do not build replacement engines for engines that are not in production. IMPCO noted, for 

example, that if the block cracks, the engine would typically be 'replaced' by bringing the piece 

of equipment to a service facility, the service facility orders an engine (block plus crankshaft) 

from the OEM or a warehouse, they remove the fuel system components, install the new block, 

and install the other, used fuel system components. IMPCO also asked how the OEM is 

supposed to know whether the short block is used for a currently certified engine family. 

IMPCO noted that the proposed regulations state that the partially complete engine exemption is 

not valid when engines are shipped to a non certificate-holder. IMPCO questioned whether 

service engines are covered? Finally, IMPCO also questioned why an exemption is needed to 

sell a replacement engine from their current production. 

IMPCO also asked if an engine produced by a secondary engine manufacturer is 

considered a New Replacement Engine once assembly is complete at its facility or after it is 

installed in the equipment. They stated that “the standard-setting part defines a New Nonroad 

Engine as the time when it is fully assembled for the first time." 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Some marine engine manufacturers pointed out that that boat owners sometimes want to 

upgrade their engines, not because they are at the end of their life but because they want more 

power, additional features, or new technologies. They suggested that manufacturers should be 

able to supply noncompliant replacement engines to meet the demand for these engines. 

Kubota commented that they would like EPA to advise Kubota on the proper wording for 

a replacement engine label that is to be used on a “replacement engine” that is going in place of a 

failed TPEM (Flex) engine. From the statement of the replacement engine label, Kubota cannot 

legally install this label onto a TPEM engine. Per the CFR and CCR, the statement would be as 

follows; "THIS ENGINE COMPLIES WITH CALIFORNIA OFF-ROAD AND U.S. EPA 

NONROAD EMISSION REQUIREMENTS FOR 2004 ENGINES UNDER13 CCR 2423(j) 

AND 40 CFR 89.1003(b)(7). SELLING OR INSTALLING THIS ENGINE FOR ANY 

PURPOSE OTHER THAN TO REPLACE AN OFF-ROAD ENGINE BUILT BEFORE 

JANUARY 1 2008 MAY BE AVIOLATION OF CALIFORNIA AND FEDERAL LAW 

SUBJECT TO CIVIL PENALTY." Because their TPEM engines would be produced after 

January 1, 2008, they have a conflict. 

Kubota suggested wording be something like: "THIS ENGINE COMPLIES WITH 

CALIFORNIA OFF-ROAD AND U.S. EPA NONROAD EMISSION REQUIREMENTS 

FOR 2004 ENGINES UNDER13 CCR 2423(j) AND 40 CFR 89.1003(b)(7). SELLING ORINSTALLING THIS ENGINE FOR ANY PURPOSE OTHER THAN TO REPLACE AN OFFROAD ENGINE BUILT BEFORE JANUARY 1 2008 OR A FLEXIBILITY PROGRAM 

ENGINE MAY BE AVIOLATION OF CALIFORNIA AND FEDERAL LAW SUBJECT TO 

CIVIL PENALTY." 

Cummins asked that the following sentence be added to §1068.240(a): “In circumstances 

involving a TPEM engine or an engine certified to a later Tier level using AB&T credits, the 

engine is considered interchangeable with a previous Tier engine for the purpose of installation 

in a piece of equipment as long as the engine is identical in all material respects to the engine 

being replaced.” 

Letters: 

Commenter Document # 

Cummins 0719 

Kubota 0744 

ECO 0802 

IMPCO 0812 

EMA 0808 

EMA 0809 

Our Response: 

While we do not necessarily agree with EMA’s assertion that previous version of the 

replacement engine exemption would be unworkable for partially complete engines, we do 

believe that the approach being finalized is more appropriate. Under the revised approach, which 

is intended to address EMA’s concerns, manufacturers will be allowed to produce replacement 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

engines (including partially complete engines) with less tracking. See section VIII.C.5 of the 

preamble and §1068.240 of the regulations for detailed descriptions of this allowance. This 

allowance will be limited for each subcategory to no more than 0.5 percent of a manufacturer’s 

annual sales for that subcategory. We agree with EMA that this allowance should apply for 

engines between 2.5 and 7 liters per cylinder. 

We disagree with the comment suggesting a high sales/production limit (1.0 percent 

instead of 0.5 percent). The comment noted that this might be especially appropriate for small 

volume manufacturers. We note that manufacturers are always allowed to produce and sell an 

unlimited number of replacement engines if they track the engines and take possession of the old 

engines. This would be a workable alternative for a manufacturer producing only a handful of 

replacement engines each year. 

It is important to note that these provisions are intended to allow for replacement of 

engines that fail prematurely where all of the following is true: 

- The engine cannot reasonably be repaired or rebuilt. 

- A different used engine (including rebuilt engines) cannot be used. 

- No new certified engine can be used. 

No matter which path the engine manufacturer uses under §1068.240, the provisions may not be 

used to circumvent emission standards that apply to new engines. Thus, boat owners are not 

allowed to use replacement engines to upgrade their engines because they want more power or 

new features. 

With respect to IMPCO’s comments, the new replacement engine allowance is intended 

to allow a small supply of replacement engines where they are legitimately needed, and not 

necessarily to allow the continuation of all current business practices without any changes. 

Under the regulations being adopted, IMPCO would be able to provide replacement engines 

through service facilities. However, this may require a new administrative process. We have 

added a new paragraph to 40 CFR 1048.601 to clarify how this would work for Large SI engines. 

With respect to the comment about current-tier engines, a replacement engine exemption is 

needed only in the case of partially complete engines that are not in their certified condition 

when introduced into commerce. 

It appears that IMPCO is confusing the definitions of “new”, “engine”, “replacement 

engine”, and “date of manufacture”. An engine produced by a secondary engine manufacturer is 

first considered an “engine” when the crankshaft is installed in the block (which occurs before it 

reaches the secondary engine manufacturer). It is also considered “new” from that point until 

title is transferred to the ultimate purchaser. However, the engine is generally considered to 

have a date of manufacture based on when it arrives at the secondary engine manufacturer. 

Whether or not it is considered a “replacement engine” has no bearing on the meanings described 

above. 

In response to EMA’s request for clarification, we note that destroying an engine 

generally means to crush, melt, or otherwise modify the engine block so that it cannot be reused 

1-64 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

as an engine. Alternatively, you may destroy an engine by modifying it to destroy its original 

identity and make it a new engine. 

We have revised the regulatory text to address Cummins’ concern, but are not using their 

recommended text. 

Finally, we have revised the labeling provisions to address concerns such as those raised 

by Kubota. 

1.5.8 List of emission-related components 

What Commenters Said: 

MIC commented that it is proposed that "All components comprising the combustion 

chamber, including the piston, piston rings, block, head, and valves" be added to the existing list 

of "emissions-related components" listed in Appendix I to Part 1068. The inclusion of these 

basic engine components would be inconsistent with the definition of "emissions-related 

components" contained in section III of Appendix I, which is "any other part whose only purpose 

is to reduce emissions or whose failure will increase emissions without significantly degrading 

engine performance." Clearly, pistons, piston rings, the block, the head and the valves do not 

have emissions control as their only purpose. Because the "failure" of any of these parts will 

clearly degrade engine performance, they should not be added to the list of emissions-related 

components. Adding such components would also be inconsistent with the way on-road vehicles 

are treated under the Clean Air Act. The implications of this change are so great that there would 

need to be a careful evaluation of the cost before proceeding. 

Arctic Cat commented on Appendix I to Part 1068 - Emission-Related Components 

(I)(5). This change greatly expands the definition of emissions related components to include the 

following: "All components comprising the combustion chamber, including the piston, piston 

rings, block, head, and valves." Arctic Cat recognizes this as a major departure from past EPA 

policy and is not consistent with how other categories are treated. It is also their understanding 

that this section is not consistent with the Clean Air Act. Arctic Cat does not feel a change of this 

magnitude it appropriate here given the absence of any discussion with industry on the nature of 

failures of the newly added components or their potential effect on emissions. In the recreational 

category failures of the newly added components have unique causes and effects which should 

be studied before proceeding with this policy change. 

OPEI commented that the list of emission components is too general and can lead to 

broad misinterpretation as to what is covered. OPEI suggests EPA use the California ARB list. 

EMA commented that EPA proposes to expand the emission related parts list (as defined 

in Appendix I to Part 1068) to include components comprising the combustion chamber, 

including the piston, piston rings, block, head, and valves. This expansion of the emission 

related parts list is not justified as those parts are critical to the basic function of the engine. 

EMA also commented on Appendix I to Part 1068 – Emission-Related Components. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

The emission related parts list as defined in Appendix I to Part 1068 is proposed to include 

components comprising the combustion chamber, including the piston, piston rings, block, head, 

and valves. This expansion of the emission related parts list is not justified as these parts are 

critical to the basic function of the engine. 

Impco commented that we should add clarifying language to the list of components 

related to evaporative emissions to take into account the fact that the standards do not apply to 

engines fueled by natural gas or LPG. 

Letters: 

Commenter Document # 

MIC 0701 

Arctic Cat 0709 

OPEI 0675 

EMA 0691 

Impco 0812 

Our Response: 

We agree with the commenters that it is not necessary or appropriate to include the 

proposed changes to the list of emission-related components. We are not adopting the proposed 

changes. 

We also agree with Impco’s input regarding natural gas and LPG engines. However, we 

have addressed this concern by adding a note to the introduction to this appendix to clarify that 

the list of components does not make parts “emission-related components” if the equipment in 

which those components are installed is not subject to evaporative emission standards. 

1.5.9 Export exemption 

What Commenters Said: 

Honda recommends that EPA apply the requirement for exemption labels ONLY when 

there is a reciprocal agreement between the United States and the other country to accept the 

EPA regulation and labeling as demonstrating full compliance with that other country’s emission 

regulations. Honda also requests that EPA develop and provide a continuously updated list of 

these countries and sufficient lead-time to comply with these requirements. Finally, Honda 

recommends that the final rule provide another section under engines for export to allow a 

manufacturer in full control of engines or products destined for another part of the world to forgo 

the temporary exemption label on individual engines or product and boxes. Small engines and 

the equipment they power are not only valuable national industries but global industries with a 

positive contribution to U.S. international trade. The ability to build engines and products in the 

U.S., exempt from EPA regulation but complying with the regulations in another country, is an 

important option that exists today. Honda understands that the purpose of the exempt label is to 

prevent inadvertent introduction of these export engines or equipment using these engine into 

U.S. commerce. However, they believe the proposed label language has significantly greater 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

content than is necessary to convey the message that the engines are for export and exempt from 

U.S. EPA regulations. Also, in many cases the engines/equipment being exported are labeled for 

compliance in another country or area, such as Europe. The combination of another country’s 

compliance label and a label stating that the engine is “not for sale in the U.S.” would be more 

likely to convey some meaning to a potential label reader and it will still be useful (and less 

likely to be misunderstood) when the engine is in another country. Furthermore, a temporary 

exemption label is not the only means of assuring that engines or products are exported and not 

introduced into U.S. commerce. If a manufacturer has full control of the engines, or equipment 

with these engines, from the point of final assembly until they have left the U.S., a temporary 

label would serve no purpose. 

OPEI provided the following comments related to the export exemption: 

• It is not clear why §1068.230 is required at all. At a minimum OPEI believes 

§1068.230(a) needs revision. The term “with emission standards identical to ours” 

creates conflict with European regulation which may have identical emission standards 

but are not identical because of the lack of an ABT program, exemptions etc. OPEI 

suggests EPA means to say “with emission regulations identical to ours.” 

• Regarding §1068.230(c), OPEI believes each engine does not need to be labeled or 

tagged if the following conditions apply: 1) the shipping container is marked and 2) A 

manufacturer has procedures to insure they are not sold in the US market. 3) If an 

engine contains an emission label from another country. Otherwise, this paragraph 

should not apply. 

Caterpillar expressed a concern that they (as the certifying manufacturer) appeared to be 

responsible even if another company would take an engine intended for export and sell that 

illegally in the United States. Caterpillar suggested that we instead identify the act of selling an 

export engine in the United States as a violation. 

Impco recommended keeping the requirement for a permanent label on export engines 

and suggested requiring that the label include the corporate name and trademark. 

Letters: 

Commenter Document # 

Honda 0705 

OPEI 0675 

Caterpillar 0813 

Impco 0812 

Our Response: 

The Clean Air Act is quite clear in describing the terms for exempting engines for export. 

Specifically, the Act calls for limiting the exemption for cases in which the other country has 

emission standards that differ from those that apply in the United States. The Act also specifies 

that exempt engines must be labeled. As a result, we have a consistent set of requirements for 

the various categories of nonroad engines, including Small SI engines regulated under part 90. 

This seems to be working today, so we do not see that there is a need for major changes to allow 

1-67 
Chapter 1: Rulemaking Process and Cross-Program Issues 

for the free flow of commerce. Nevertheless, we are making three adjustments to the export 

exemption in §1068.230 to address the concerns raised by commenters. 

First, we are establishing a streamlined path for certifying export-only engines where the 

destination country has the same emission standards. In particular, we would look for 

certification or other approval from the destination country as the basis for approving the exportonly certification. Also, the requirement to pay certification fees would be waived for these 

engines. This special certification would be valid only for purposes of exporting the engines and 

would not be sufficient for selling the engines in the United States. 

Second, we are clarifying what requirements apply for removable (or temporary) labels. 

In contrast to Honda’s concern, we do not require permanent labels today for exported engines, 

nor did we propose such a requirement. For example, we specify that manufacturers can apply a 

removable label to exempted engines by labeling the container where multiple engines are 

packaged together. This is especially advantageous for Small SI engines where dozens of 

engines may be packaged together. In place of the removable label, manufacturers may 

alternatively apply a permanent label specified by the destination country if such requirements 

apply, in which case the bill of lading would need to also state that the engines must be sent to 

the named destination country to avoid a violation. 

Third, we are revising the regulation to state that the exemption expires when the engine 

leaves the country. Anyone subsequently importing such an engine would therefore be guilty of 

a violation, rather than the original manufacturer. However, if at any point in the manufacturing 

or distribution process such an engine is placed into service in the United States, the certifying 

manufacturer would be held responsible for the violation. Manufacturers would do well to take 

steps to ensure that anyone responsible for installing or distributing such engines understands 

how important it is to avoid a situation where these engines are placed into service in the United 

States. 

We agree that it is necessary to clarify what provisions apply for defining when another 

country has emission standards identical to ours. We would generally understand standards to be 

identical if they specify the same numerical level of the standard, the same test procedures 

(including fuel specifications), and the same approach for allowing the use of emission credits. 

For example, Canada currently specifies that Small SI engines used there must meet U.S. EPA 

standards. These engines would therefore not be eligible for an export exemption and must 

therefore be certified with EPA. However, Canada also specifies that a limited number of 

engines used in specialty applications may meet the Phase 1 standards rather than the current 

Phase 2 standards. These engines would be exempt from our emission standards and 

certification requirements because the applicable standards are clearly different than those that 

apply to Small SI engines produced for the United States for the given model year. If a 

manufacturer requests an exemption to export engines/equipment to a country that has standards 

similar but not identical to ours, we may ask the manufacturer to specify how such standards 

differ from ours. We may attempt in a future rulemaking to add language to the regulation to 

clarify when we would consider standards to be identical. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Note that engine manufacturers do not need an exemption or any special approval to ship 

engines that are certified and labeled for the U.S. market if some of those engines may be 

diverted for export by distributors or retailers. 

Impco incorrectly pointed out that current regulations specify a permanent label for 

export engines. The regulations specifically state that the label need not be permanent. This is 

appropriate since there is no benefit of having the label once the engine is outside the United 

States. Moreover, manufacturers have pointed out that a permanent label would be problematic 

once the engine is sold and placed into service in another country. We agree that the label 

should identify the manufacturer’s corporate name and trademark and have changed the 

regulation accordingly. 

1.5.10 Manufacturer-owned exemption 

What Commenters Said: 

EMA commented that adding “possession” to the list of qualifying criteria for the manufacturerowned exemption adds a significant constraint on manufacturer’s ability to complete all the 

requirements associated with introducing new products into the marketplace. 

Impco similarly objected to including the word “possession” to the list of qualifying criteria for 

the manufacturer-owned exemption, noting that another company should be able to execute a 

development program on their behalf without triggering the need for EPA approval under the 

testing exemption. 

Letters: 

Commenter Document # 

EMA 0808 

Impco 0812 

Our Response: 

The existing manufacturer-owned engine exemption specifies that “an engine may be 

exempt without a request if it is a nonconforming engine under your ownership and control and 

you operate it to develop products, assess production methods, or promote your engines in the 

marketplace.” We proposed to add the word “possession” to this language as a clarification 

because we discovered that some manufacturers mistakenly believed this exemption allowed 

them to provide these engines to customers for testing. Clearly, the existing language prohibits 

anyone other than the manufacturer from operating the engines. Thus, this revision is not 

changing the provisions that currently apply under the manufacturer-owned engine exemption; 

we are adding the word “possession” simply to eliminate any confusion. 

It is a separate issue whether we should allow manufacturers to relinquish possession of 

these engines without obtaining a test exemption. However, we continue to believe that engines 

exempted as manufacturer-owned engine need to be strictly controlled since this exemption does 

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not require prior EPA approval. Anyone wishing to arrange for someone else to operate engines 

may ask for EPA approval under the testing exemption. 

1.5.11 Other issues 

What Commenters Said: 

GE commented that the proposed §1068.420 as it would apply to an engine family when 

evaluated as part of a Selective Enforcement Audit (SEA) establishes failure criteria that are less 

stringent for new locomotives than the criteria established in §1033.415 for in-use locomotives 

that have between 50% and 75% of useful life service. The criteria in §1068.420 and Appendix 

A indicates that a failure rate of 60 % or more is required to establish that an engine family is 

noncompliant whereas §1033.415 mandates a test procedure that when extended to the maximum 

allowable number of 10 test locomotives logically establishes that a failure rate of 40% or more 

could be considered a noncomplying engine family based on the failure rate and EPA’s judgment 

and consideration of other test results such as average emissions levels, existence of any defects, 

and other unspecified test factors. GE believes that it is illogical and unrealistic to expect 

locomotives that have been in service for 50% to 75% of their useful life to have an emissions 

compliance rate greater than the EPA has established for new locomotives and recommends that 

the compliance criteria for in-use testing in §1033.415 be changed to be no more stringent than 

that set for new locomotives as established in proposed §1068.420 and Appendix A. 

California ARB encourages EPA to revise the provision in 1068.250(j) that would allow 

the extending of compliance deadlines for small businesses for up to three years total. At most, 

California ARB believes that the relief should be granted for two years in cases of extreme 

hardship. A two-year period should be sufficient to provide any manufacturer, even a small 

business entity, adequate time to achieve compliance. 

California ARB also commented that the provisions of part 1068 apply to nonroad diesel 

engines, large spark-ignition engines, recreational vehicles, small spark-ignition engines, and 

marine spark-ignition engines. Although a unified program may appear to be easier for 

manufacturers to follow, it may be difficult to implement due to the distribution of various 

engine types in different business sectors. 

OPEI commented on the following items: 

• §1068.110(e) suggests owners can do diagnosis and repair themselves and charge 

manufacturer. This needs to be reworded to clarify that owners should file their 

warranty claims through dealers or other authorized representatives. 

• §1068.210 conflicts with language in §1060.215(b). The provisions in §1068.215(b) 

should apply for development and test engines. OPEI asks whether §1068.215(b) does 

not apply to a test exemption. When developing new products, an important component 

of the program is field testing in real world conditions. Often units are placed with 

various test crews that use them in their normal day-to-day business activities. The units 

are monitored by the manufacturer and at the end of the test period, collected, reviewed 

and usually scrapped. While the crew is generating revenues by the use of the 

equipment, the manufacturer is not. OPEI asks how they apply this exemption for 

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testing/developing new engines/equipment. OPEI also asks why §1068.315 does not 

include test exemptions. 

• OPEI requests EPA include emails as an acceptable form of owner notification of recall 

in §1068.520(a). OPEI notes that §1068.520(a)(9) requires a self-addressed card. OPEI 

asks about using an Internet site or toll-free number instead. 

EMA commented on the following proposed items. 

• The proposed definition of engine-based test appears to relate exclusively to exhaust 

emissions that are reported in g/kW-hr. Instead of engine-based test, the defined term 

should be “Engine-based Exhaust Emission Test” in order to differentiate between testing 

an engine for exhaust emissions and testing associated with demonstration of compliance 

with evaporative requirements that are either already in place (such as those for LSI and 

Recreational Vehicle), or those being proposed (such as those for Small SI or marine SI 

engines). 

• The proposed definition of an incomplete engine assembly does not make sense and must 

be removed or carefully revised in a subsequent rulemaking in light of the discussion 

above regarding the definition of an engine. 

• The proposed definition of a secondary engine manufacturer also will need to be revised, 

as necessary, based on the ultimate resolution of the definition of an engine and/or 

incomplete engine. As such, it should be deferred to a subsequent rulemaking. 

• The proposed language addressing the practice of engine sector changes needs to be 

modified to make it clear that an engine that changes sectors, for example from nonroad 

to stationary, retains the engine’s original date of manufacture and is subject to that 

sectors applicable standards for that original date of manufacture. 

• The NPRM requests comments on applying any or all of the ‘special compliance 

provisions’ proposed for Small SI engines in Part 1054 to all nonroad engines by 

incorporation into Part 1068. The NPRM provisions for Small SI engines include several 

topics including: warranty coverage, bonding requirements, model year naming for 

imported engines, reporting requirements, etc. that require significant discussion with the 

various affected industries covered by Part 1068 prior to implementing these changes. 

EMA is ready to work with the agency to develop the required outreach and appropriate 

changes to Part 1068 but is concerned that the addition of this burden will delay the Final 

Regulation. (See 72 FR at 28212.) 

• EMA supports the optional early adoption of 40 CFR Part 1068 (rather than the similar 

compliance provisions in parts 89, 90, 91 and 94) but objects to making this earlyadoption mandatory. Many of the Part 1068 changes require significant resources to 

implement, and manufacturers may desire to implement these changes at the same time as 

the emissions standards change. (See 72 FR at 28212.) 

Arctic Cat commented that sometimes a wrecked snowmobile can be fixed by replacing 

the tunnel (upon which the emissions label is affixed). The snowmobile must be wrecked in just 

the right way to call for tunnel replacement, otherwise it is usually totalled. A handful of times a 

year Arctic Cat has customers order tunnels and they have been asked about the emissions label. 

Arctic Cat assumes a new emissions label should or must be affixed as part of the repair since the 

old label would be discarded with the damaged tunnel. They cannot find any rules governing 

this situation. Such rules or guidance documents would be helpful in defining our policies. 

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Impco suggested that we modify §1068.105 to clarify that equipment manufacturers are 

subject to penalties if they do not follow the regulations, including emission-related installation 

instructions, and to add explanatory language to make it clearer what equipment manufacturers 

must do. 

Letters: 

Commenter Document # 

GE 0679 

California ARB 0682 

OPEI 0675 

EMA 0691 

Arctic Cat 0731 

Impco 0812 

Our Response: 

GE’s comment on the proposed §1068.420 is no longer relevant because the recently 

finalized 40 CFR 1033.601 excludes locomotives from Selective Enforcement Audits. 

We intend to evaluate hardship applications submitted under §1068.250(j) on a case-bycase basis. We generally agree that one or two years of hardship relief should be adequate for 

almost all cases. However, we believe it would not be appropriate to change the regulation to 

rule out even the possibility of considering longer hardship relief for exceptional circumstances. 

Part 1068 indeed applies broadly. The scope of part 1068 now includes all nonroad 

engine categories, though some types of engines will not be subject to part 1068 until new 

standards apply sometime in the future. We believe there are strong advantages to including 

these general compliance provisions in a single place in the regulations. Keeping one set of 

regulations current is straightforward, since we will not need to update parallel regulatory 

provisions when we amend the regulations periodically. We see no particular challenge in 

implementing these general compliance provisions for multiple engine categories as a result of 

this approach to adopting the regulations in one location. There are occasions where we need to 

make distinctions for certain engine types, but this is routinely handled directly in part 1068 or 

with clarifying provisions in the standard-setting part. This is certainly no greater challenge than 

having the entire program written separately for each engine category. 

We have revised §1068.110(e) to clarify that manufacturers may require that owners 

submit warranty claims only through authorized repair facilities, consistent with OPEI’s 

suggestion. 

 The manufacturers’ comments show that they have misinterpreted the provisions in 

§1068.210 and §1068.215. In particular, §1068.215 specifies that the manufacturer-owned 

exemption is limited to engines owned and controlled by the manufacturer such that they are not 

used in revenue-generating service. It is incorrect to assert that this does not require actual 

possession of the engines by the engine manufacturer, or that the engines may be used to 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

generate revenue, as long as the revenue does not go to the engine manufacturer. We are 

therefore adopting the clarifying change to include “possession” as an explicit requirement to 

qualify for the manufacturer-owned exemption. We understand that manufacturers have a 

legitimate need to share experimental engines with their customers, including those that may be 

used in revenue-generating service. However, the test exemption in §1068.215 is the appropriate 

path for these engines. The test exemption is available only upon request, which gives us the 

opportunity to be involved and aware of such engines. Engine manufacturers that hold a 

certificate of conformity (for any engine model or application) must generally submit only a 

minimal set of information and can have an exemption approved to cover a two-year period. 

This involves a minimal burden for the manufacturer, but keeps us informed of the status of 

these engines. We believe it would not be appropriate to allow for this practice without requiring 

the engine manufacturer to identify the basic elements of their plans to introduce such engines 

into U.S. commerce. As for importation, the testing exemption is temporary, so it is described in 

§1068.325 rather than §1068.315. It may turn out that engines are scrapped before the 

exemption expires, but it is still the case that the exemption applies for a given time period rather 

than for the life of the engine. 

We agree that the regulation should acknowledge that Internet, e-mail, and toll-free 

phone numbers are legitimate alternatives to communication by traditional mail service. 

The term “engine-based test” is used only in limited cases and in each instance the 

meaning of the term clearly applies only for exhaust emission testing. This also aligns with the 

intuitive understanding that engines are generally tested for exhaust emissions and equipment (or 

fuel-system components) are tested for evaporative emissions. We therefore believe it is not 

necessary to change the proposed definition. 

The regulations no longer use the term “incomplete engine assembly” so we have 

removed this definition from §1068.30. 

We have revised the definition of “secondary engine manufacturer” to reflect the input 

received regarding partially complete engines. As such, we see no need to defer these regulatory 

provisions or definitions until a later rulemaking. 

We agree that the regulation should include clarifying language to state that changing an 

engine from stationary to nonroad would not cause the engine to be subject to standards based on 

the date of the conversion. Nonroad standards would apply based on the original date of 

manufacture. We have revised §1068.31 accordingly. 

We have chosen to include the restriction related to naming model years for imported 

products in part 1068, rather than including that only for Small SI engines. We placed the 

revised regulatory language in the rulemaking docket and interacted with the Engine 

Manufacturers Association and several individual manufacturers to confirm that these provisions 

could be applied more broadly than just for Small SI engines. EMA’s suggestion to waive the 

restriction for engines or equipment originally produced in the United States would be difficult to 

implement. It would be difficult for Customs to differentiate incoming products based on 

whether or not they had an actual point of origin within the United States. Perhaps more 

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importantly, such a policy would likely be impermissible under the rules governing international 

trade, since it would clearly provide preferential treatment for domestically produced items. 

We are adopting the other special compliance provisions, such as warranty assurance and 

bonding, only for Small SI engines. We may propose to apply these provisions for other engine 

categories in a later rulemaking. 

In the absence of any supporting comments related to accelerating the migration to the 

general compliance provisions in part 1068, we are not making any broad changes to require 

earlier compliance with the regulatory provisions in part 1068. We agree, however, that there 

may be good reasons for manufacturers to opt into the part 1068 provisions before they would 

otherwise apply. Since these provisions represent the long-term plans for all nonroad engines, 

we are including a provision allowing manufacturers to comply with specific provisions of part 

1068 early. 

We agree that the regulations should include specific provisions to address the various 

responsibilities related to replacing emission control information labels due to accidents or other 

need for repairs. The engine manufacturer should be responsible for providing duplicate labels 

in these cases and should take steps to ensure that the labels are applied properly. These 

duplicate labels should include all the information from the original label except for the date of 

manufacture, which would be impractical to include as described in Section 1.3.2. 

We agree with Impco’s recommendation to modify §1068.105 and have changed the 

regulation accordingly. 

1.6 Certification fees (40 CFR part 1027) 

What Commenters Said: 

EMD included a comment about the certification fees for locomotive remanufacture 

systems in its written submission to docket EPA-HQ-OAR-2003-0190.11 They reiterate it here, 

in its more proper venue. The certification fees rule, included in 40 CFR Part 85, allows a 

reduced certification fee if the fee exceeds one per cent of the “aggregate projected retail sales 

price of all vehicles or engines covered by that certificate.”12 That language is carried over to 

the proposed Part 1027.13 In the case of emissions remanufacture systems, EPA interprets this 

provision to mean the price of the locomotives to which the kits are applied. This interpretation 

means that an engine family consisting of remanufacture systems whose price fairly reflects their 

contents has no chance of qualifying for a reduced fee unless sales of the systems certified under 

that family are zero, because the fee is much less than one per cent of the value of even one 

locomotive. 

EMD commented that this situation is unfair to system manufacturers. EMD believes that 

the intent of the rule is to give manufacturers relief if their economic benefit is not commensurate 

with the cost of certification. The economic benefit to the manufacturer of a remanufacture 

system is the revenue to be gained by the sale of the system, not the value of the locomotive to 

which it is to be applied. It appears that the rule was written with only engines and complete 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

vehicles sold by a manufacturer in mind, omitting consideration of remanufacture systems, 

which are a collection of parts with only a small fraction of the value of the complete engine or 

vehicle. EMD requests that this rule section be rewritten to include one per cent of the aggregate 

retail sales price of remanufacture systems, not the price of the locomotives to which they are 

applied, as the parameter for comparison to the certification fee to qualify for a reduced fee.14 

The modification should be applied both to the applicable section of the current rule, Part 85, and 

to the new Part 1027. 

EMD continued that EPA proposes to adjust certification fees only if the adjustment 

would exceed $50 per engine family. EMD opposes this proposal. EMD’s engine families are in 

the “Other” category, which includes locomotives and compression-ignition marine engines, as 

well as other smaller classes of engines. Since fees were initially assessed in 2005, the fee for 

this category has declined from $826 to $802. EMD believes that it will continue to decline as 

the number of certification applications in this category increases. Therefore, the effect of EPA’s 

proposal would be to hold the fee at an artificially high level until the adjustment reached $50, 

increasing EPA’s revenue from this program at the expense of manufacturers. EPA should 

continue to adjust fees annually as required by the rule currently in force. 

Letters: 

Commenter Document # 

EMD 0687 

Our Response: 

We agree with EMD’s suggestion to reconsider the cost basis for reduced fees for 

remanufacturing kits. We already have provisions in place for fuel-conversion kits in which the 

regulation specifies that the basis for evaluating the one-percent threshold is the value of the kit 

rather than the value of the engine. This applies anytime the particular engine is already covered 

by a certificate of conformity based on the original fuel. We believe a remanufacturing kit is 

analogous to a fuel-conversion kit for purposes of certification fees. While the remanufacturing 

kits may in some cases be applied to uncertified engines, in all cases the remanufacturing kits 

(and not the engine that is being modified) define the scope of the certification. We are therefore 

modifying the regulation to allow for reduced fees where the assessed fee is more than one 

percent of the value of the remanufacturing kit or remanufacturing system. This applies equally 

to locomotives and marine diesel engines, which are now also subject to remanufacturing 

certification provisions. 

We disagree with EMD’s assessment and recommendation regarding annual fee 

adjustments. We believe it is rather short-sighted to make a long-term policy decision based on 

an extrapolation of the trend from the last two or three years. While there have been substantial 

additional numbers of applications for certification recently, there is reason to believe that the 

calculated fee will not universally trend downward. First, some new applications result from the 

introduction of new emission control programs, such as for Large SI engines and recreational 

vehicles, which are clearly one-time effects. Second, while there has been a large number new 

companies certifying products from overseas, we are concerned in some cases about the ability 

of these companies to fulfill their obligations for warranty, recall, and other in-use compliance 

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provisions. We are taking steps in this rule to make clear that certification is more than a onetime requirement, which we believe will serve as a disincentive for some companies that may 

otherwise have thought that certification provided a simple and clear path for introducing 

products into the U.S. market. We believe this trend will stabilize at some point. Third, even if 

these trends persist, it will not be long before the calculated fee exceeds the $50 threshold and we 

will change the fees accordingly. Fourth, inflation is part of the equation for calculating fees. 

We would not expect the effect of increasing numbers of certificates to always be enough to 

offset inflationary effects. Over any reasonable time frame, we would still expect the proposed 

provision limiting annual fee changes to be revenue-neutral. 

EMD did not address the underlying reason for the proposal to limit annual fee changes. 

Our proposal was focused on minimizing confusion and administrative errors. To the extent that 

fees do not change from year to year, there will be fewer mistakes when people make their 

payments. Under the current program, it is not uncommon for people to overpay or underpay by 

a nominal amount. It is time-consuming, awkward, and wasteful to spend the time required to 

collect an additional $8 because an applicant was not aware that the fee had increased. Looked 

at from the other side, the cost to the government of issuing an $8 refund is about $75. We 

believe the public benefit of avoiding administrative errors far exceeds the benefit to EMD from 

reducing certification fees by $24. 

Finally, there is a place for being cost-conscious; however, we believe the amounts in 

question hardly warrant controversy. In the most extreme case, under the proposed rule we 

would have a fee that is $49 less than it could be with an automatic annual readjustment. If 

EMD would sell a single locomotive in the family, the certification fee would be about 0.003 

percent of their revenue for that one locomotive. With actual sales in the hundreds of units and 

expectation that these cost differentials will be much closer to zero, even this estimate vastly 

overstates the relative burden represented by the fee that is higher than the calculated value. 

We find that our original reasons for limiting annual fee adjustments are unchanged. We 

are therefore finalizing these provisions as proposed. 

1.7 Preemption of state regulations (40 CFR part 1074) 

We have addressed comments related to preemption of state regulations in “Response to 

the Petition of American Road and Transportation Builders Association to Amend Regulations 

Regarding the Preemption of State Standards Regulating Emissions from Nonroad Engines,” 

July 25, 2008. 

1.8 Technical amendments for Large SI engines (40 CFR part 1048) 

1.8.1 Fuel tank permeation 

What Commenters Said: 

IMPCO commented that EPA proposed that nonmetal fuel tanks must use a qualifying 

design specified in 1060.240 § 1048.245 How do I demonstrate that my engine family complies 

with evaporative emission standards? 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

(e) (1) (i) ... Nonmetal fuel tanks must also use one of the qualifying designs for 

controlling permeation emissions specified in 40 CFR 1060.240. 

According to §1060.1, these new LSI permeation standards are effective Model Year 

2007.IMPCO requests that this be changed to MY2010. Given that it is now August 2007, it is 

too late for MY2007 design to change and MY2008 designs are frozen. Additionally, because 

MY2009 is an emissions carryover year, engine manufacturers did not anticipate making any 

design changes until MY2010. 

ECO commented that they think the real concern for Genie is when the new requirements 

will come into effect. 

Letters: 

Commenter Document # 

Impco 0692 

ECO 0741 

Our Response: 

We agree that allowing some lead time for implementing the design requirements related 

to plastic fuel tanks is appropriate. Delaying the implementation date until the 2010 model year 

should make it possible for companies to work with fuel tank suppliers to coordinate plans for 

making a smooth transition toward making compliant products. 

1.8.2 Diurnal emission testing 

What Commenters Said: 

IMPCO noted that the proposed regulations state that a gas cap must be tethered or selfclosing and stay sealed up to a positive pressure of 24.5 kPa. IMPCO commented that the 

definition of ‘sealed’ is still somewhat nebulous. IMPCO suggested that, among other allowable 

designs, the following should also be considered ‘sealed’: 

- A fuel cap design used by an automotive OEM that has been certified under the EPA or 

California ARB enhanced evaporative emissions standards, or 

- A fuel cap that is listed under UL 558, ‘Industrial Trucks, Internal combustion EnginePowered’ 

- Calculated HC emissions from the gas cap are less than some percentage of the evap 

standard (possibly less than 20%) over the 24-hr diurnal test (include a standard value to 

use for the % of HC in air at a certain temp) 

Protectoseal believes their fuel caps can comply with the proposed requirements to stay 

sealed. Protectoseal noted that they have defined the set point of our caps as the positive 

pressure at which the caps first exhibit bubble leakage. Depending on the cap size and style, this 

bubble tight set point is between 3.5 psig and 4.5 psig. The caps are further designed to provide 

venting relief as the positive tank pressure increases beyond this set point. The caps also provide 

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vacuum relief (under negative pressure conditions) to allow make-up air to enter the fuel tank 

and allow smooth flow of fuel to the engine. (Protectoseal included literature sheets that provide 

representative data of the flow/leakage data of the caps under pressure and vacuum conditions.) 

Protectoseal noted that they have worked with Underwriters Laboratories to make sure that the 

caps meet all their functional and safety related requirements (as evidenced by the UL Listing for 

our new designs) while also minimizing emissions into the atmosphere when the cap assembly is 

subjected to positive pressure. 

Letters: 

Commenterd Document # 

Impco 0614 

Protectoseal 0615 

Our Response: 

We understand that an unqualified requirement to maintain sealed fuel tanks can be 

problematic, if only to recognize that a tank with undetectable leaks may nevertheless experience 

an infinitesimal vapor loss through very small imperfections in gasket materials, especially as 

materials age in normal service. Protectoseal’s experience demonstrates that the concern for 

leaks is not a question of feasibility with respect to detectable leaks as measured by normal 

diagnostic tests. As a result, we do believe it is not necessary to add the several options 

recommended by Impco for demonstrating that a fuel cap will adequately keep a fuel tank sealed. 

Rather, we are revising the regulation to require only that sealed tanks prevent measurable leaks. 

This should avoid a situation where someone feels at risk of being noncompliant based on 

extremely low leakage rates. Underwater “bubble tests” would be one appropriate method for 

establishing whether there is a measurable leak. 

1.8.3 Certification related to evaporative emission standards 

What Commenters Said: 

ECO commented in order to address the inherent complications related to evaporative 

certification for LSI and SD/I engine families, ECO suggests that EPA consider establishing a 

component certification process for engine system / equipment components that have a bearing 

on the evaporative emissions of the engine / equipment. For instance, EPA should consider 

allowing equipment OEMs, or component manufacturers, to conduct their own independent 

certification of evaporative system components, including fuel tanks, lines, and caps. The format 

of this program could follow the format that the California ARB utilizes for Small SI engine 

evaporative components. 

Letters: 

Commenter Document # 

ECO 0712 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

We adopted evaporative emission requirements with the understanding that the large 

majority of gasoline-fueled engine models would be in installed in metal fuel tanks. In this 

scenario, designing systems to control permeation and diurnal emissions is very straightforward. 

Now that we are implementing these requirements, it has become clear that plastic fuel tanks are 

an important exception to accommodate. We have seen that it is impractical to expect engine 

manufacturers to be responsible for including plastic fuel tanks in their application for 

certification, since they generally are not involved in designing, shipping, or installing the fuel 

tanks. We believe it is appropriate to allow fuel tank manufacturers or equipment manufacturers 

to certify fuel tanks separately. We have revised part 1060 to allow for this certification path. 

1.8.4 Definition of small-volume manufacturer 

What Commenters Said: 

ECO commented that 1048.801 defines a small volume manufacturer as an engine 

manufacturer with U.S.-directed production volumes, subject to Part 1048, totaling no more than 

2,000 engines per year. It also defines a SVM as an engine manufacturer with fewer than 200 

employees. Although ECO agrees with the redefinition of SVM, the new definition is missing 

the distinction that a company qualifies as a SVM by meeting either of the two criteria, not both. 

To provide a precise definition of SVM, the first sentence of the definition should read “Smallvolume engine manufacturer means either one of the following.” 

California ARB’s current large spark-ignition engine regulations do not have assigned 

DFs for small volume engine manufacturers. However, California ARB accepts EPA-approved 

“assigned DFs” for small volume engine manufacturers during the certification process. Due to 

variability of emission control technologies designed for large spark-ignition engines, California 

ARB will continue to work closely with EPA to review and approve “assigned DFs” on a caseby-case basis. 

Letters: 

Commenter Document # 

ECO 0712 

California ARB 0682 

Our Response: 

ECO’s interpretation of the proposed change to the definition of small-volume engine 

manufacturer is consistent with our intent. We have changed the wording of the definition to 

make this distinction clearer. 

We look forward to working with California ARB further regarding assigned 

deterioration factors. 

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1.8.5 Additive deterioration factors 

What Commenters Said: 

IMPCO strongly supports allowing manufacturers to use either Multiplicative or Additive 

DFs. With more sophisticated engine technologies and ever-decreasing emissions, even the 

slightest increase in emissions can tremendously affect a multiplicative DF calculation. For 

example, with a low-hour value of 0.1 g/kW-hr and a 2,500-hr value of 0.3 g/kW-hr, the 

extrapolated 5,000-hr multiplicative DF is 5.000. However, an additive DF would be 0.400 

g/kW-hr, which is far more representative of in-use deterioration. 

ECO commented that newly added text to 40 CFR §1048.240(c)(2) states that engine 

manufacturers may utilize additive DFs for engine families with low-hour emission levels below 

0.3 g/kW-hr. The mandatory use of multiplicative deterioration factors (DF) penalizes low 

emission engines, as the multiplicative deterioration process creates an exponential penalty for 

engines that produce extremely low 0-hour emissions. Because the allowance to use additive DFs 

encourages the development of the lowest emitting engine technologies, ECO and their 

stakeholder group fully support this change and encourage EPA to retain the additive DF 

allowance in the final rule. 

In subsequent comments, ECO suggested changing the threshold for using an additive DF 

from 0.3 g/kW-hr (for all pollutants), to one based on measured low-hour test results less than 11 

percent of the applicable standard. Alternatively, the threshold for CO could be increased to 0.48 

g/kW-hr. These adjustments would take into account the higher numerical standard for CO. 

ECO also suggested in the later comments that the regulation should state that a given 

engine might use an additive DF for one pollutant and a multiplicative DF for another pollutant. 

California ARB supports using an additive DF if the emission levels are below 0.3 g/kWhr. The use of an additive DF for engines with very low emission levels can accommodate the 

mathematical effects during the durability calculation. 

Letters: 

Commenter Document # 

Impco 0692 

ECO 0712 

California ARB 0682 

ECO 0798 

Our Response: 

We agree that a slight increase in the accommodation for additive DFs for CO are 

appropriate. Since the mathematical and technological effects that lead to additive DFs are 

driven by the magnitude of the emission levels, not the compliance margin, we believe the best 

approach is to adopt a fixed threshold of 0.5 g/kW-hr for CO. This approach involves a 

consistent level of precision relative to the threshold for HC+NOx emissions. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

The regulatory language in §1048.240 clearly provides for a separate decision regarding 

additive and multiplicative deterioration factors for HC+NOx and CO. This should make clear 

that the decision for an additive deterioration factor for one standard does not require an additive 

deterioration factor for the other standard. 

1.8.6 Field-testing demonstration for constant-speed engines 

What Commenters Said: 

Intertek/Carnot recommended an approach to demonstrating for certification that 

constant-speed engines meet the field-testing standards. We requested comment on this because 

there is no longer a transient test requirement for constant-speed engines. The recommended 

testing involves ten minutes of engine operation consisting of steady operation for 20 seconds 

under several different load conditions. The test would be run like a ramped-modal cycle, except 

that the transitions between modes would last three seconds for increasing engine load in 20-

percent increments and they would last five seconds for increasing load in 40-percent 

increments. The cycle does not include operation at full load, since spark-ignition engines 

generally don’t operate for an extended time at full load. See the figure below for the detailed 

sequence of engine loads. 

Letters: 

Commenter Document # 

Intertek Carnot 0740 

Our Response: 

We believe the recommended cycle provides a good tool for evaluating whether constantspeed engines will adequately control in-use emissions under engine operation not included in 

the D2 cycle used for steady-state testing. This includes changes in engine load that would be 

common for typical in-use operation (increasing pump output, adding devices powered by a 

generator, etc.). These changes would not always occur with this frequency, but we believe this 

schedule of engine operation is realistic for many in-use scenarios. If manufacturers have 

information available to show that a different approach is more appropriate for their engines, we 

would consider approving alternative demonstrations. This might involve testing with the 

original constant-speed transient test, or some other schedule of engine operation to better reflect 

a relatively worst-case scenario of engine operation. 

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Constant Speed Engine Ramped Modal Cycle 

0 

10 

20 

30 

40 

50 

60 

70 

80 

90 

100 

Load Factor, [% Ra 

Ramp Modal Cycle 

Sec-by-Sec Cmd 

120-sec Rolling Load Avg 

Condi t i oni ng 

<3 Sec Ramps, 20 sec 

<5 Sec Ramps, 20 

sec Hol d 

<3 Sec Ramps, 20 sec 

<5 Sec Ramps, 20 

sec Hol d 

120 sec rolling avg includesemissions/ load 

60secbeforeandaf ter therollingpoint 

-100 0 100 200 300 400 500 600 

Duration, [sec] 

1.8.7 Other issues 

We included several technical amendments for part 1048, which led to a variety of 

comments on relatively minor issues. This section describes these comments and our responses 

to them. We additionally address comments related to applying an engine’s build date on the 

emission control information label in Section 1.3. 

What Commenters Said: 

IMPCO commented that EPA proposed to remove the requirement for constant-speed 

engines to meet the transient emissions standards in 1048.101(a). IMPCO strongly supports this, 

as the transient test cycle or constant-speed engines is not at all characteristic of constant-speed 

engine operation. The steady-state test cycles are far more representative and appropriate. 

IMPCO also commented that EPA proposed to remove (b)(1) through (b)(11) of the 

AECD detailed description in the application for certification. IMPCO strongly supports this. It 

is important to document all AECDs to ensure that the proper regulatory guidelines are being 

followed. However, the additional time required to detail every aspect presently identified in the 

regulations creates an unnecessary burden on the manufacturer while providing little to no 

incremental benefit to EPA. 

IMPCO also commented regarding § 1048.120(c), 1048.240(b), 1048.605(c)(2), 

1048.610(d)(2), 1068.101(b)(2), 1068.120(a), 1068.501(a). Several areas throughout the 

proposed regulations refer to an increase in exhaust emissions of any pollutant. Pollutant should 

be defined only as those regulated under Parts 63, 1048, et al. 

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ECO commented on page 28148 of the Federal Register notice, section E(1) 

Deterioration Factors proposes an allowance for small volume engine families to utilize assigned 

deterioration factors. Additionally, on page 28213 of the proposal, EPA requests input on the use 

of assigned DFs for small volume engine families and requests comment on the appropriate 

production threshold for this allowance. ECO and their stakeholders feel this provision is 

necessary to allow flexibility for small volume SSI engine families. ECO also agrees with EPA, 

that the allowance to use assigned DFs for small volume engine families should also be 

incorporated into the large spark-ignition (LSI) engine rules contained in 40 CFR 1048. As it 

stands, there are numerous companies that do not meet the definition of small volume 

manufacturer (ref. 40 CFR 1048.801), but that produce one or more families of engines with 

production quantities of only a few hundred per year. This small production quantity does not 

allow MORs the ability to recoup costs associated with a typical durability operating cycle 

(2,500 hours), and often results in MORs discontinuing the certification and production of 

marginal product lines. ECO recommends that EPA consider the use of assigned deterioration 

factors for all LSI engine families with annual production quantities less than 300 units. 

California ARB commented on the following sections: 

- 22. Diurnal Temperature Cycle (40 CFR part 86.133-96): 40 CFR part 86.133-96 

requires a diurnal temperature cycle not common in California or much of the southwest. 

The temperature profile used by California ARB to represent California conditions is 65-

105°F. California ARB recommends EPA modify the rule to require the more restrictive 

profile, which in addition to harmonizing, would ensure the expected emissions 

reductions are achieved even in the warmer parts of the country. 

- 23. Diurnal Standard (40 CFR part 1048.105): 40 CFR part 1048.105 requires tanks to 

meet the diurnal standard of 0.2 grams per gallon-day (g/gal-day). California ARB agrees 

that 0.2 g/gal-day is currently achievable. California ARB has test data that shows 0.1 

g/gal-day may also be achievable. California ARB suggests that EPA propose a future 

date that includes the more stringent 0.1 g/gal-day standard. 

- 24. Pressure Standard (40 CFR part 1048.245): 40 CFR part 1048.245 requires a 

standing pressure test of 3.5 pounds per square inch absolute (PSIA). California ARB test 

data shows that on occasion tanks in California and presumably other warmer states can 

reach above 4.0 PSIA. California ARB recommends increasing the test standard to 5.0 

PSIA. 

- 25. Production Line Testing Exemption (40 CFR part 1048.301(a)(2)): EPA’s 

proposal exempts large spark-ignition engine families with a projected U.S.-directed 

production volume below 150 units from routine production line testing. However, 

production line testing is an important tool to ensure that manufacturers are meeting the 

requirements. Therefore, EPA should reconsider this exemption. California ARB plans 

to retain its current requirement for small volume manufacturers to test one percent of 

their California production. 

- 26. Production Line Testing Procedures (40 CFR part 1048.305(a)): EPA’s proposal 

requires manufacturers to use either the steady-state or transient testing procedures to 

show that the production-line engines meet the exhaust emission standards. However, it is 

still not quite clear which test cycle should be used to generate DFs for production line 

testing. EPA should clarify that it will not allow manufacturers to use a DF generated by 

a steady-state test cycle to apply to a production line test using a transient test cycle. 

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- 27. Exhaust Emission Standards for Large Spark-Ignition Engines <1 liter (L) (40 

CFR part 1054.105(a) Table 1): California ARB recommends that EPA modify its 

proposed HC+NOx phase-in schedule for large spark-ignition engines ≤ 1 L to harmonize 

with the California small off-road engine exhaust emission standards for class II engines, 

8 g/kW-hr at 2008 model year. This would provide for significant emission reductions 

from this category. Furthermore, a harmonized program would help reduce the problem 

of higher emission 49-state large spark-ignition engines traveling into the California fleet. 

EMA commented that total engine displacement should be rounded to the nearest whole 

cubic centimeter. Accordingly, §1048.615(a)(1) should be revised to read as follows: “The 

engine must have a total displacement at or below 1000 cc after rounding to the nearest whole 

cc.” 

Caterpillar suggested that we make the following changes to the regulations related to 

natural gas engines: 

• Modify 1048.620 to point towards 40CFR60 subsection JJJJ as the optional approach for 

transportable SI engines. This would allow either factory certification or site compliance 

testing, account for the varying fuels common to these applications, and still assuring 

emissions compliance. 

• Remove the 250kw cutpoint and include all engines down to 25 hp, as that is where part 

90 requirements are in effect for all small SI engines. This will then harmonize with the 

regulatory strategy in 40CFR60 subsection JJJJ. 

• As 1048 already regulates gasoline and rich-burn LPG, this exemption need not apply to 

these fuels. However, all other fuel types should be included in the exemption. This 

harmonizes with the approach taken by 40CFR60 subsection JJJJ as well. 

Letters: 

Commenter Document # 

Impco 0692 

ECO 0712 

California ARB 0682 

EMA 0691 

Caterpillar 0814 

Our Response: 

We agree that the constant-speed transient cycle should be omitted from the regulation, as 

described in the proposed rule. We may pursue a more appropriate constant-speed transient duty 

cycle in a future rulemaking. 

We agree that simplified AECD descriptions in the application for certification are 

appropriate, as described in the proposed rule. Manufacturers have the incentive to be thorough 

in describing their AECDs in the application for certification to avoid a situation where AECDS 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

are detected outside of the certification process and questions are raised regarding whether the 

AECD qualifies as a defeat device. 

We agree that all the references to pollutants in part 1068 should specifically refer to 

“and regulated pollutant.” We have also changed the regulation at §1048.120 to refer to “any 

regulated pollutant.” The reference in §1048.240 is clearly written in the context of pollutants 

that are subject to emission standards, so this change is unnecessary. The provisions in 

§1048.605 and §1048.610 are based on the expectation that the engine is installed in a nonroad 

piece of equipment without any changes that would affect fuel or air intake, combustion, or 

aftertreatment. It is therefore not clear that the regulation should specifically limit this provision 

to regulated pollutants. While we would not normally monitor compliance with respect to 

nonregulated pollutants, we would be interested in understanding why such an increase might 

occur. 

As noted in the preamble, we are adopting provisions for assigned DFs for Marine SI and 

Small SI engines for small-volume engine manufacturers and for small-volume engine families. 

This is intended to address the concern that the costs of generating DFs can be quite large 

relative to revenues for niche products, even for very large companies. This same dynamic 

applies for Large SI engines, though to a larger degree. With a 5,000-hour useful life, the cost of 

generating DFs for an engine family are much greater than for Marine SI or Small SI engines. 

We agree with ECO’s recommendation to adopt a provision allowing for assigned DFs for 

engine families with annual U.S.-directed production volumes at or below 300 units. 

We adopted a temperature profile for diurnal emission testing that is consistent with the 

approach we take for light-duty vehicles. California’s approach for light-duty vehicles is to 

specify the higher temperatures but specify a test fuel with lower volatility. EPA and California 

ARB have concluded that these two sets of test parameters yield very similar results. It is 

unlikely that changing the temperature and test fuel would lead to any design changes for 

improved control of emissions. We therefore believe it is appropriate to keep our existing 

regulation intact. 

We adopted the diurnal emission standard expecting that most manufacturers would opt 

for the certification alternative to keep fuel tanks sealed up to 3.5 psi. This effectively achieves 

complete control for all but the large majority of summer days. For example, a fuel tank filled 

halfway with 9 RVP fuel would reach a pressure of 3.5 psi if ambient temperatures ranged from 

72 to 96°F. We specify evaporative testing using these conditions to represent nearly a worstcase condition. The 3.5 psi specification is also consistent with the industry standard under 

UL558, so manufacturers have considerable experience in supplying products that comply with 

this pressure requirement. It is not clear that there would be a significant environmental benefit 

with higher-pressure fuel caps, or that such caps would be readily available for the full range of 

equipment that would need them. For manufacturers electing to test their systems to demonstrate 

compliance with the diurnal emission standard, it is not clear that a more stringent standard is 

appropriate. We are in the second year of implementing the diurnal emission standards and will 

be learning from this experience. Canister capacities and purge systems, the most likely 

alternative design solution, have been used for many years with light-duty vehicles, but there is 

little information available to show that a more stringent standard is appropriate. We would be 

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interested in reviewing California ARB’s information when it is available. However, it is not 

clear that the more stringent standard would lead to a meaningfully improved emission controls 

with in-use engines and equipment. 

Production-line testing for Large SI engines relies on CumSum statistical calculations. 

To be able to make a pass/fail decision for an engine family, two test results are required to 

initiate calculations related to sample sizes and overall compliance. California ARB intends to 

limit testing to 1 percent of production, but for production volumes below 150, a one-percent rate 

in this case translates to a single engine. This was the primary basis for EPA’s decision to waive 

production-line testing requirements for these small families. California ARB may continue to 

require testing for these engine families, but it is not clear single-engine testing can be reconciled 

with the need to use CumSum calculations to reach a conclusion. 

Emission measurement during transient engine operation is very important for testing an 

engine’s ability to control emissions over a wide range of in-use operation. We believe 

manufacturers should be able to choose whether to establish a single DF (for a pollutant) based 

on a comparison of emission measurements using transient operation only, or to generate 

separate DFs for transient and steady-state testing. We agree that it is not appropriate to allow 

manufacturers to use a DF from steady-state testing to characterize the aging effect for transient 

emission measurements. Selecting the type of engine operation for service accumulation is very 

different. We believe a variety of approaches can be used to properly age an engine. The most 

important parameters to consider are engine load (torque) and exhaust temperatures. It is not 

apparent that service accumulation based on transient engine operation is an important factor 

aside from considerations of average engine load and exhaust temperatures. 

Manufacturers of engines at or below 1000 cc must meet the emission standards that 

apply for Class II Small SI engines to be exempt from the more stringent Large SI emission 

standards. We are including an update to reference the new standards for Small SI engines in 

part 1054. This provision requires manufacturers to meet the currently applicable phase of 

standards, so no further regulatory change will be necessary if or when we adopt an additional 

phase of standards for Class II engines. 

We agree that §1048.615 should continue to apply for engines at or below 1000 cc (not 

1000.0 cc), consistent with the original regulation. 

The Clean Air Act requires that nonroad engines be certified before they are introduced 

into U.S. commerce. We are therefore unable to modify §1048.620 to make certification 

optional, as suggested by Caterpillar. This requirement does not apply to stationary engines. We 

may consider in a future rulemaking to specify the emission standards in part 60, subpart JJJJ, as 

being sufficient for certifying engines under §1048.620, but we would need to go through the 

notice-and-comment process for such an initiative. We established a threshold of 250 kW for 

these engines to avoid competitive effects where automotive-based natural gas engines would be 

potentially serving the same markets as the diesel-derived natural gas engines. 

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1.9 Technical amendments for recreational vehicles (40 CFR part 1051) 

1.9.1 Maintenance 

What Commenters Said: 

MIC commented that 1051.125(d) defines the components specified in 40CFR Part 1068, 

Appendix I as being items of noncritical emission-related maintenance, but some of these 

components are also listed as critical emission-related components specified in § 1051.801, 

which causes mismatch. MIC recommends that the language be changed as follows: 

"...any other emission-related maintenance on the components other than critical 

emission-related components." While spark plugs are noncritical emission related components, 

the maintenance and inspection of them can be critical emission related maintenance. 

Manufacturers would like to have the ability to inspect and clean them during service 

accumulation on the emission-data vehicles. Federal Register Vol. 67, No. 217, pg. 68321 C.2 

indicates that the EPA may allow changing spark plugs even though they are aware that spark 

plugs may affect emissions. 

Letters: 

Commenter Document # 

MIC 0701 

Our Response: 

We have revised §1051.125 to clarify the relationship between critical and noncritical 

emission-related maintenance. 

1.9.2 Test procedures 

What Commenters Said: 

ISMA understands that raw gas sampling is permanently allowed for snowmobiles under 

the provisions of 40 CFR Part 1065. However, they note that calculation procedures similar to 

the fuel flow method in 40 CFR Part 90.419(c ) and 40 CFR 91.419(c ) for converting the raw 

gas sampling measurements into g/kW-hr emission levels are not explicitly provided in Part 

1065. The fuel flow method is commonly used by the snowmobile manufacturers under the 

interim provision of 1051.145(e)(1), which allow use of the raw sampling procedures from parts 

90 or 91 through the 2009 model year. 40 CFR 1065.601(c)(1) is intended to implicitly allow a 

functionally equivalent fuel-flow calculation method, based on reference to the ISO 8178 

standards. The indirect allowance of 40 CFR 1065.601(c)(1) and the fact that the ISO 8178 

standards are not freely available in the public domain have caused considerable uncertainty for 

the snowmobile manufacturers regarding the available raw-gas sampling options beyond model 

year 2009. The manufacturers note that the direct final rule for ATV’s published in the Federal 

Register on April 26, 2007 extends the use of the raw gas sampling methods in 40 CFR part 90 

or part 91 through the 2014 model year for ATV’s. Since all of the ISMA members are ATV 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

manufacturers familiar with these established methods, and since ATV manufacturers are 

allowed to continue using these methods for ATV’s, ISMA proposes that EPA also extend the 

use of the raw sampling procedures in parts 90 or 91 through the 2014 model year for 

snowmobiles. This would provide the Agency with the time to codify more explicitly in Part 

1065 the fuel flow method allowance that we understand is embodied in ISO 8178. It would also 

allow the ISMA member companies to use just one method for all of their raw gas sampling 

during the remaining time period that engine-based testing is permitted for ATV’s. 

Letters: 

Commenter Document # 

ISMA 0671 

Our Response: 

We agree that an allowance for continued use of raw sampling procedures under part 90 

or 91 is appropriate. As an interim measure, we are revising the regulation to allow this for 

demonstrating compliance with the Phase 1 and Phase 2 standards. We intend to revisit this 

question as part of the effort to revise the Phase 3 standards. We will at that time decide when 

manufacturers would appropriately be subject to testing requirements under part 1065. 

1.9.3 Determining maximum engine power and displacement 

What Commenters Said: 

MIC commented that §1051.140 is a new section describing how to determine an 

engine’s maximum power and displacement. This section references the 40 CFR part 1065 

mapping procedures to determine maximum power. Those procedures require test equipment that 

can measure engine power during transient conditions as engine speed is changing. Compliance 

with the proposed new requirement involves significant equipment costs that do not contribute to 

greater emissions control. MIC therefore recommends that SAE J1349 be allowed as an 

alternative method for measuring maximum engine power. In calculating displacement, the 

proposed language requires “using enough significant figures allow determination of the 

displacement to the nearest 0.1 cc” while also stating that “An engine configuration’s 

displacement is the intended swept volume of the engine rounded to the nearest 0.5 cubic 

centimeter”. The standards applicable to ATVs are defined based whether the engine size is less 

than 225 cc or equal to or greater than 225 cc. It would therefore be more consistent to specify 

that the swept volume should be rounded to the nearest cc, rather than the nearest 0.1 cc. There is 

also an error in the example calculation incorporated in the proposed section. The correct 

displacement for the example values used is 176.7 cc, not 176.5. 

Letters: 

Commenter Document # 

MIC 0701 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

Manufacturers depend on the proper value of maximum engine power to calculate 

emission credits for averaging, banking, and trading. Manufacturers also need to determine 

maximum engine power to establish whether an offroad utility vehicle is above or below 30 kW. 

It is important to use an objective criterion to establish maximum engine power to ensure that 

manufacturers don’t use available discretion (as under SAE J1349) to manipulate credit 

calculations or change the standards that apply for their products. It is also important to ensure 

that different programs use the same metric to establish whether standards apply to avoid overlap 

or gaps between programs. Maximum engine power is fundamentally a design value and does 

not necessarily require testing. The reference to the mapping procedures clarifies which design 

value is appropriate. We also specify that the nominal value for maximum engine power must 

fall within the range of values from production engines. This testing is not required, but it allows 

us to verify that the declared value is appropriate, especially for preventing manufacturers from 

gaining an advantage by declaring a value for maximum engine power that does not represent 

production engines. 

We agree that the regulation specifies displacement values (such as 225 cc) only to the 

nearest cubic centimeter. We have therefore revised the regulation to require manufacturers to 

report displacement values to the nearest centimeter. However, to ensure that these reported 

values are accurate, we are keeping the requirement to use methods that allow for determining 

the displacement to the nearest 0.1 cc before rounding. 

The comment pointing out an error in the calculation underscores the need for an 

example to illustrate the regulatory provision. The example calculation is correct, though the 

question is moot because of the change in precision described above. 

1.9.4 Deterioration factors 

What Commenters Said: 

MIC commented that 1051.243(b)(6) says “You may use other testing methods to 

determine deterioration factors, consistent with good engineering judgment, as long as we 

approve those methods in advance.” MIC’s concern with this language is that resource 

constraints at EPA sometimes preclude detailed consideration of alternative testing methods even 

when they have been developed using “good engineering judgment.” To address this practical 

concern, this subsection needs to be revised to read, “You may use other testing methods to 

determine deterioration factors, consistent with good engineering judgment, unless we provide 

an engineering analysis within 30 days demonstrating that the proposed method is not 

acceptable.” 

Letters: 

Commenter Document # 

MIC 0701 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

Our Response: 

We understand that there may be good reasons to modify plans for generating DFs for a 

given engine family. At the same time, evaluating such changes often involves more than a 

simple assessment. We are especially sensitive to the need for review of such requests based on 

many recent experiences with companies trying to exploit every possible angle to reduce the 

burden associated with certification, with no apparent regard to the environmental impact of 

these decisions. While an expedited response would clearly be of interest for manufacturers in 

many cases, but we believe it would be a good policy—or even in the manufacturer’s best longterm interest—in setting a deadline for EPA’s response. For example, if we would discover after 

30 days that there is a problem with the manufacturers plan, there would need for further testing, 

either for extended service accumulation for a given emission-data vehicleor for restarting the 

durability testing altogether. If the EPA approval step is unacceptable, the only viable option is 

to remove the provision for alternative DF demonstrations. 

1.9.5 Other issues 

What Commenters Said: 

ISMA commented recognizing the litigation that impacted on Phase 3 of the US EPA 

Rule for snowmobiles, they believe the published standard for Phase 3 in 1051.103 may be 

appropriately designated as "reserved" status. 

ISMA commented that they do not support the proposed change in 1051.205(t). 

Production volumes are based on market analysis and behavior. These volumes can shift 

significantly from year to year from circumstances outside of a manufacturer's control. It is 

inappropriate for EPA to require a "justification" for a change in estimated production volumes 

from year to year. 

ISMA does not support the recommended change in 1051.250 (a). Clearly this should not 

apply to corporate averaging engines which are already required to file two separate reports 

throughout the year. The snowmobile manufacturers provide actual production number on a 

quarterly basis in their PLT reports. In addition, manufacturers are required to provide final 

production volumes in their corporate average report. ISMA recommends EPA exempt 

manufacturers not using small-volume compliance provisions from this requirement. 

ISMA does not support the recommended change to 1051.310 (b)(3). ISMA agrees with 

EPA it is appropriate for carry-over engine families to combine the last PLT test result from the 

previous model year with the first PLT test result from the current model year to determine the 

number of PLT tests required. However, EPA has proposed to add two sentences to 1051.310 

(b)(3) which serve no purpose except to increase the test burden on a manufacturer, "Use the last 

test result from the previous model year only for this first calculation. For all subsequent 

calculations, use only results from the current model year. ISMA requests the last two sentences 

from this paragraph be deleted. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

MIC and ISMA commented that it does not appear that the proposed deletion of the 

reference to “vehicle” testing from section 1051.315 is appropriate because some engine families 

are certified based on vehicle testing. 

ISMA question why in 1051.350 the limit for keeping files has been switched from 1 year 

to 8 years. Also, additional definition is needed regarding the specific records being referenced. 

MIC commented that proposed changes to 1051.350 increase the requirement for 

retaining paper records from 1 year to 8 years. If the retention period is going to be extended 

such a large amount then the requirement for “paper” records should be replaced with “paper or 

electronic” records. 

MIC commented that the explanation for proposed changes to §1051.701 includes the 

statement that “We are also clarifying that a single family may not generate emission credits for 

one pollutant while using emission credits for another pollutant, which is common to all our 

emission control programs.” However, the proposed requirement is not common (e.g., this issue 

was specifically addressed for snowmobiles during the recent rulemaking and EPA agreed that 

credits for one pollutant could be used by a family generating credits for another pollutant. This 

proposed change needs to be deleted. 

ISMA commented that in 1051.801 EPA proposes to amend 40 C.F.R. § 1051.801 to 

redefine the term “designated compliance officer,” in such a way as to treat snowmobiles 

differently than all other types of vehicles regulated under 40 C.F.R. part 1051 (i.e., off-highway 

motorcycles, ATVs, and certain utility vehicles and other types of motorcycles). Specifically, 

snowmobile issues would be handled by the Manager of the Heavy-Duty and Nonroad Engine 

Group in Washington, D.C., while all other part 1051-regulated vehicle issues would be handled 

by the Manager, Light-Duty Engine Group in Ann Arbor, Michigan. ISMA opposes this 

amendment and notes that EPA nowhere explains this proposal in the preamble to the proposed 

rule, and at the very least must do so in the preamble to the final rule. ISMA’s members are 

entitled to expect EPA to minimize and not proliferate administrative compliance costs, and to 

that end should face a compliance approach that is designed to partner with manufacturers to 

pragmatically solve day-to-day issues arising from applying the part 1051 regulations. The 

Section 1051.801 proposal is not pragmatic. ISMA can see no rational basis on which EPA 

could cleave off compliance activities for snowmobiles from compliance activities for other 

types of vehicles regulated under part 1051. Thus, ISMA does not know how EPA could justify 

requiring companies that already face significant administrative compliance costs to duplicate 

their efforts across disparate parts of the Agency. This is particularly apparent to ISMA because 

each of ISMA’s members manufacture both snowmobiles and ATVs. In general, it makes little 

sense to have different compliance officers interpreting and applying part 1051. Moreover, such 

a questionable organizational change fragments, and renders inefficient EPA’s own operations, 

and it imposes added administrative compliance costs on manufacturers of products that 

arbitrarily must deal with one set of officials for one set of vehicles, and another for another set 

of vehicles, even though both types of vehicles are regulated by precisely the same part 1051 

regulations. It makes sense to position the compliance officer for all vehicles regulated under 

part 1051 at the location that currently serves the greatest number of vehicles. 

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MIC commented that having a unique Designated Compliance Officer for snowmobiles 

would require companies that manufacture other types of vehicles to deal with two different 

offices on very similar, if not identical issues. For efficiency and consistency, it would be 

preferable to have snowmobile issues handled by the Ann Arbor office. 

MIC commented regarding 1051.730. The intent of this subsection would be clarified if 

the term “sales weighted” is replaced with “U.S.-directed production weighted” instead of simply 

“production weighted.” 

Robin America requested the following change to the Part 1051. If an engine 

manufacturer has general purpose engines approved (exhaust & evap) to either Parts 90 or 1054 

they should be able to use these engines in ATV’s without having to meet the 1051 exhaust 

specifications. This will enable engine manufactures to sell general purpose standard spec engine 

to ATV manufactures without any additional testing on the part of either manufacturer. This 

change should be stated such that they can use previously approved engine from now until 2015 

when the mandatory chassis testing is required. 

Sierra Research commented that they heard that EPA was going to state 2010 model year 

at least for the labeling requirements. Also, they know in the Heavy-Duty world the use of older 

testing methodologies are allowed for some time while part 1065 requirements are made to lab 

facilities; will the same be allowed for the Recreational Vehicle category under 1051.140? Will 

older test data be useable as carry-over once the 1065 testing requirements become applicable? 

Letters: 

Commenter Document # 

ISMA 0671 

MIC 0701 

Arctic Cat 0709 

Robin America 0743 

Sierra Research 0742 

Our Response: 

There are two issues related to the Phase 3 standards for snowmobiles. First, the court 

decision stated that we do not have legal authority under the Clean Air Act to set NOx standards 

for snowmobiles and required that we remove the NOx component from the Phase 3 standards. 

We have addressed this in a separate rulemaking (72 FR 35946, June 25, 2008). Second, the 

court required that we provide further clarification and justification for the Phase 3 standards we 

set. We intend to address this second question in a separate rulemaking well before the Phase 3 

standards are scheduled to take effect. We may or may not conclude that the Phase 3 standard 

needs to change. We therefore believe it is not necessary or appropriate to remove the Phase 3 

standard from the regulation at this time. 

The current requirement for manufacturers to estimated projected production volumes 

does not allow us to require realistic estimates. There are provisions in the regulations that 

depend on realistic projections, so we believe it is necessary for us to specify that these 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

projections be based on proper assumptions. Records of previous production volumes and an 

assessment of current market conditions allow companies to plan for ongoing production rates. 

We would not expect to ask manufacturers to justify projected volumes for every family, but we 

might ask for more information if the sales projections depart substantially from those of earlier 

model years, especially where the projection would seem to provide an advantage for the 

company under the regulations. At the same time, we understand the recreational vehicles are 

particularly prone to periods of irregular demand, with the resulting variation in year-to-year 

sales figures for their products. We believe it is appropriate to keep the proposed requirement to 

use realistic values for projecting sales volumes for the upcoming model year. 

We have changed the reporting requirements in §1051.250 to align with the reporting that 

manufacturers already do for production-line testing and credit reports. Specifically, we are 

requiring that manufacturers report their production volumes to the extent that those figures are 

not already included in these other reports. This is merely intended to complete the reporting 

requirement for cases where there are vehicles produced after PLT reports are complete (or if 

there is no production-line testing required for the family) or in cases where the manufacturer is 

not participating in the emission-credit program. 

The changed language in §1051.310 (b)(3) will not increase manufacturers’ test burden. 

The use of the test result from the previous model year is necessary in the first quarter of the new 

year is necessary to avoid an automatic second test in the first quarter. In the second quarter, the 

result from the first quarter can be combined with the new result from the second quarter to make 

the required CumSum calculations. There is therefore no longer any need to consider the result 

from the previous model year in the calculations for the current model year. The new language 

is intended merely to clarify the existing requirements, so we expect no additional test burden. 

We are adopting the new language as proposed. 

We agree that the term “vehicle” should be preserved in §1051.315. This change was 

inadvertent. 

We proposed to increase the time frame for keeping records to eight years to allow us to 

review the validity of the production-line testing throughout the time that these vehicles will be 

operating. This is consistent with the recordkeeping we require in our other emission control 

programs. We agree that keeping electronic records is sufficient, as long as the manufacturer can 

provide a printed copy of these records upon request. Since these records will generally stored 

electronically, we expect there will be little if any additional effort to keep the records for a 

longer time. The records that need to be kept are specified in considerable detail in §1051.345. 

We agree that the current regulations allow manufacturers to generate emission credits 

for one pollutant while using emission credits for another pollutant with a given engine family. 

Disallowing this practice would effectively increase the stringency of the emission standards. 

We are therefore removing this provision from the final rule. We may revisit this issue for any 

more stringent standards that we set in future rulemakings. 

The role of the Designated Compliance Officer in the regulations is simply intended to 

provide a point of contact for submitting information and requesting approvals. The regulation is 

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not intended to dictate Agency decisions related to work flow or decision-making relative to 

internal organizational structures. We will be deciding how to manage and implement the 

certification process for recreational vehicles independent of the description and address noted in 

the definition of “Designated Compliance Officer” in §1051.801. Nevertheless, to reflect the 

fact that two of the three types of recreational vehicles are handled out of the Ann Arbor office, 

we are revising the regulation to specify that as the default location for the Designated 

Compliance Officer. 

We agree that §1051.730 should use the defined term “U.S.-directed production volume”. 

We understand Robin America’s interest in using certified Small SI engines for all-terrain 

vehicles (ATVs). We believe that conventional ATVs (straddle seat, handlebars, etc.) should be 

certified under part 1051 since those products are generally well established, high-volume 

products. It would not be appropriate to accommodate the interest in simplifying the 

certification process for these products. In contrast, the ATV definition also captures other 

rough-terrain vehicles that in many cases are low-volume niche products. We believe these 

vehicles can many times benefit appropriately from using certified Small SI engines based on the 

fact that these products are not as well established as high-volume recreational products. We are 

therefore adopting this allowance for these ATVs through the 2014 model year. Starting in 

2015, manufacturers must certify their vehicles based on a chassis test, after which the ATV 

emission standards will be inherently different than the Small SI standard, as acknowledged by 

Robin America in its comment. 

The regulations in part 1065 specifically state that manufacturers may delay complying 

with amended requirements for up to twelve months after those changes become effective. 

Many of the changes we are making to the regulations do not impose new requirements, but 

rather add flexibility or clarify existing requirements. The provision to delay complying with 

amended requirements allows for a more gradual transition when a regulatory change indeed 

imposes a new or different requirement. We are adding a similar provision in §1068.40 that 

would allow for delayed compliance with technical amendments in part 1068 or in the standardsetting part. Regarding the date of manufacture on engine labels, we are specifically stating that 

the new requirement does not apply until the 2010 model year. 

1.10 Technical amendments for heavy-duty highway engines (40 CFR parts 85 and 86) 

What Commenters Said: 

EMA recommended that we delay the requirement to use the procedures in part 1065 

until July 2010. To prevent this from impacting the stringency of the standards, they 

recommended specifically excluding certain provisions from the delay. They recommened that 

the regulations specify the following provisions from part 1065: 

(1) Generate a map of your engine according to 40 CFR 1065.510(b)(5)(ii) and generate 

test cycles according to 40 CFR 1065.610. Validate your cycle according to 40 CFR 

1065.514. 

(2) Follow the provisions of 40 CFR 1065.342 to verify the performance of any sample 

dryers in your system. Correct your measurements according to 40 CFR 1065.659, 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

except use the value of Kw in §1342-90(i) as the value of (1-xH2Oexh) in Equation 

1065.659-1. 

(3) Verify your NO2-to-NO converter according to 40 CFR 1065.378. 

(4) For diesel engine testing, correct NOx emissions for intake-air humidity according to 

40 CFR 1065.670. 

(5) You must comply with the provisions related to analyzer range and drift in 40 CFR 

1065.550. If drift correction is required, correct your measurements according to 40 CFR 

1065.672, but use the emission calculations specified in this subpart N rather than those 

specified in 40 CFR 1065.650. 

(6) You must comply with 40 CFR 1065.125, 1065.127, and 1065.130, except for 

references to 40 CFR 1065.530(a)(1)(i), 1065.640, and 1065.655. 

(7) Follow the provisions of 40 CFR 1065.370 to verify the performance of your CLD 

analyzer with respect to CO2 and H2O quench. You are not required to follow 40 CFR 

1065.145(d)(2), 1065.248, or 1065.750, which are referenced in 40 CFR 1065.370. 

Letters: 

Commenter Document # 

EMA 0768 

Our Response: 

We agree with the manufacturers’ comment and have revised the regulation accordingly. 

1.11 Technical amendments for stationary engines (40 CFR part 60) 

What Commenters Said: 

EMA commented that Small SI engines generally are considered mobile due to their 

small size and relatively light weight. However, there are engines that meet the definition of 

Small SI yet, in fact, are utilized in stationary product applications. The EPA New Source 

Performance Standard (NSPS) for spark-ignition engines correctly requires such Small SI 

engines to meet the same emission requirements as their mobile counterparts. There are many 

cases where a Small SI engine that is certified, produced, and labeled as a mobile engine will 

actually be utilized in a stationary application. This industry practice must be maintained, and 

should not be adversely affected by the imposition of unnecessary labeling requirements that 

provide no environmental benefit. The final regulation should clarify that engines that are labeled 

as compliant with nonroad standards may be utilized in stationary sources without alteration, or 

additional labeling requirements. 

EMA also stated that Small SI engine manufacturers do not have the ability to determine 

if an engine family may contain models that are subsequently utilized in a stationary application. 

As the proposed requirements for stationary and nonroad engines are intended to be identical, 

this differentiation is not significant. Accordingly, §90.107(d)(13) should be deleted. 

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Exergy commented that it is their understanding the proposed rule does not apply to 

engines for stationary power generation and/or shaft driven equipment using natural gas and/or 

propane. If EPA's proposed rule does apply, is there an exemption for stoichiometric and/or lean 

burn 19 kW continuous duty or long duty-cycle (greater than 1,000 hours per year) engines for 

stationary power generation and/or shaft driven equipment using natural gas and/or propane? 

EMA suggested that we add clarifying language to §1068.31(c) to specify that the 12-

month limit does not apply for fixed engines (i.e., neither portable nor transportable). 

Cummins raised question about how to apply the definition of “nonroad engine” for 

engines that are installed in a fixed location. Aside from clarifying whether the requirement for 

such an engine to operate for at least 12 months to be considered stationary, they suggested 

adding regulatory language that would: 

• Allow certain engines to be considered 'stationary' even if not at a given site for 

more that 12 months. Aside from the seasonal engine provision, this should 

include engines in natural gas production that are connected to the fixed fuel 

supply but that might need to move early due to lack of production. (Note that 

these engines are typically mounted in a frame/skid with compressing equipment, 

radiator, etc, and typically sit on a prepared dirt site.) 

• NOT allow other engines connected to a fixed fuel supply for less than 12 months 

to be considered 'stationary'. An example recently discussed would be an SI 

genset mounted in a trailer on wheels. Such a unit ought to be able to connect to a 

fixed, natural gas fuel source for, say, three months without being considered 

stationary. 

Because of the need to have engines in different applications, attached to a fixed fuel 

supply for a short period of time, to be treated differently, perhaps this would be better addressed 

by 'intent'. In the first example above, the intent would be for the unit to operate more than 12 

months in the given location. In the second example, the intent would be to operate less than 12 

months. The first example ought to be a stationary situation; the second example ought to be 

nonroad. Cummins did not recommend specific language to accomplish this, but suggested the 

following adjustment to paragraph (2)(iii) of the nonroad engine definition: 

"An IC engine is not a nonroad engine if it meets any of the following criteria: ... (iii) 

The engine otherwise included in paragraph (1)(iii) of this definition remains, or will remain, or 

is intended to remain at a location for more than 12 consecutive months..." [emphasis added] 

In response to draft language for §1068.31(c) to clarify the status of stationary engines 

that are neither portable nor transportable, Caterpillar suggested revised wording to make clear 

that the residence-time restrictions are the subject of the sentence, not the definition of a nonroad 

engine. The initial language was: 

“Note that the definition of ‘nonroad engine’ in §1068.30 generally does not apply the residence-time 

restriction to engines that are neither portable nor transportable in actual use.” 

The suggested revision was: 

“For engines that are neither portable nor transportable in actual use, residence time restrictions generally 

do not apply to the definition of a non-road engine in 1068.30.” 

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Letters: 

Commenter Document # 

EMA 0691 

Impco 0692 

Exergy 0627 

Cummins 0785 

Caterpillar 0822 

EMA 0808 

Our Response: 

The regulation setting standards for stationary SI engines below 19 kW recognizes the 

points raised by EMA about the interchangeability of nonroad and stationary engines in this size 

range. The regulation specifies a single label for engines below 19 kW whether they will be used 

in nonroad applications, stationary applications, or both. It is important to note, however, that 

state and local governments are not preempted from setting standards for stationary engines, 

even if the engines are already certified to meet EPA’s nonroad standards. 

While the requirements for stationary and nonroad engines are identical, we may approve 

certain procedures separately for one or the other of these applications. We would expect only 

that the manufacturer would make a good-faith indication of how its engines might be used. 

There would be no violation if that expectation turns out not to be true in a way that could not 

have been predicted ahead of time. 

It is not clear how Exergy could have thought that the proposed standards in part 1054 do 

not apply to stationary engines, since we stated clearly in the preamble and in the regulations that 

the standards apply equally to stationary and nonroad engines below 19 kW. There is no 

exemption available for any of the engine types or applications noted by Exergy. 

The definition of “nonroad engine” applies residence-time requirements to portable and 

transportable engines to ensure that they are considered stationary only if they remain in one 

location for an established duration. Fixed engines (lacking the features that would make them 

portable or transportable) are inherently stationary, so the residence-time requirements do not 

apply to them. We would expect such engines to remain in one location for longer than the times 

we specify for portable engines, but it would not be a violation to move an engine before the 

specified period was complete. We agree that it is appropriate to add the clarifying language in 

§1068.31 to state that “for engines that are neither portable nor transportable in actual use, the 

residence-time restrictions in the definition of “nonroad engine” generally do not apply.” 

Cummins’ suggestion to rely on intent to determine whether an engine is stationary or not is 

unworkable. This would effectively make it impossible to hold someone responsible for moving 

an engine more frequently (or sooner) than is allowed under the regulation. 

We have no objection to Caterpillar’s suggested adjustment to the language in 

§1068.30(c) and have modified the regulation accordingly. 

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1.12 Technical amendments for nonroad diesel engines (40 CFR parts 89, 92, 94, 1033, 

1039, and 1042) 

What Commenters Said: 

General Electric suggested that we modify the regulation in part 1033 to allow varying dilution 

ratios for different test modes. 

Letters: 

Commenter Document # 

General Electric 0786 

Our Response: 

We agree that it would be appropriate to address very small PM sample rates either by 

extending the sampling time or by adjusting dilution ratios, consistent with good engineering 

judgment. The original requirement in §1068.515 specified only the extended sampling time, but 

we believe the varying dilution ratios can be equally effective in making an accurate 

measurement. 

1.13 Benefit calculations for ozone mortality 

What Commenters Said: 

Environmental Defense commented regarding EPA’s Omission of Ozone Health Benefits 

is Arbitrary and Capricious and Contrary to Law. The harmful effects of ozone on human health 

and the environment are well documented. Indeed, the body of science linking ozone with 

premature mortality is one of the most significant developments in the last decade. The current 

proposed rule, if implemented, will greatly reduce emissions of ozone-precursors thereby 

achieving significant ozone-related health benefits. In light of the robust health benefits of this 

proposal Environmental Defense objects to EPA’s failure to quantify any ozone benefits, 

including ozone-mortality. In its initial draft impact analysis, EPA estimated that by 2030 the 

proposed spark-ignition engine standards would result in the reduction of 631,000 tons of 

volatile organic hydrocarbon and 98,200 tons of oxides of nitrogen emissions. EPA projected 

that these reductions will likely correspond to significant reductions in the formation of groundlevel ozone and would prevent between 60 and 360 ozone-related premature deaths, 800 

hospitalizations, and almost 50,000 work days lost. EPA estimated the total benefits of this 

proposed rule range between $3.9 billion and $6.1 billion annually. However, EPA ultimately 

deleted all references to the above-listed quantified ozone benefits in response to pointed 

comments by the White House Office of Management and Budget. In the final Draft Regulatory 

Impact Analysis, EPA admits that it “typically quantifies ozone-related health impacts in its 

regulatory impact analyses when possible” and that “[I]n the analysis of past air quality 

regulations, ozone-related benefits have included morbidity endpoints and welfare effects such as 

damage to commercial crops.” Nevertheless, EPA states that it is deviating from its “typical” 

practice due to a lack of conclusive scientific information as to how to quantify the benefits of 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

ozone-related mortality. Furthermore, in order not to “provide an incomplete picture of all of the 

benefits associated with reductions in emissions of ozone precursors,” EPA declined to quantify 

other health and welfare benefits. 

 Environmental Defense strongly disagrees with the assumption that there is insufficient 

information to include a valuation of mortality benefit. They also strongly object to EPA’s 

failure to quantify any ozone benefits, such as crop damage, lost work days or hospitalizations. 

Environmental Defense believes that EPA’s failure to consider the ozone mortality and 

nonmortality benefits associated with the proposed rules is arbitrary, capricious and contrary to 

law. See State Farm, 462 U.S. 29, 43 (finding agency failure to consider “an important aspect of 

the problem” arbitrary and capricious). Indeed, consideration of the full benefits of the emission 

reductions at stake only underscores the imperative of the Agency adhering to its statutory 

mandate under section 213 of the CAA to immediately take final action adopting emission 

standards that reflect the “greatest degree of emission reduction achievable” and “take effect at 

the earliest possible date.” 

Letters: 

Commenter Document # 

Environmental Defense 0648 

Our Response: 

 Though omitted in the proposal for this rulemaking, EPA agrees that there is sufficient 

evidence to include a valuation of the mortality benefit. We therefore quantify and monetize the 

ozone-related health impacts associated with the final rule, including both mortality and nonmortality impacts. This reflects EPA’s most current understanding of the science surrounding 

ozone impacts on human health and welfare, consistent with the recent ozone criteria document, 

the analysis of the final ozone NAAQS, and the recently published report (April, 2008) by the 

National Research Council titled, “Estimating Mortality Risk Reduction and Economic Benefits 

from Controlling Ozone Air Pollution.” 

1.14 Air quality analysis 

What Commenters Said: 

NACAA commented that state and local clean air agencies across the country are facing 

the enormous challenge of developing strategies to achieve and maintain the health-based 

National Ambient Air Quality Standards (NAAQS) for ozone and fine particulate matter (PM2.5). 

Air quality in approximately 120 areas of the nation currently violates the 8-hour ozone standard, 

the PM2.5 standard or both, exposing more than 150 million people to unhealthful levels of air 

pollution. Clearly, considerable efforts by EPA, states and localities will be needed to reduce the 

widespread health and environmental impacts associated with emissions from contributing 

sources. In addition, EPA has already taken action to tighten the PM2.5 NAAQS and recently 

proposed similar action on the ozone standard, which will increase the challenges facing states 

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and localities. Further, many areas of the country are plagued by unacceptably high levels of 

toxic air pollution. 

NACAA continued to comment that emissions from the nonroad spark-ignition engines 

covered by this proposal are substantial. Use of lawn and garden equipment totals more than 3 

billion hours a year. A gasoline-powered push mower currently emits as much hourly pollution 

as 11 cars, a riding mower as much as 34 cars. Recreational watercraft can emit as much hourly 

as 348 cars. The resulting emissions contribute to unhealthful concentrations of PM2.5, ozone, 

CO and toxic air pollutants, which translate into serious adverse health impacts, including 

premature death, heart disease, aggravated asthma and other respiratory conditions, as well as a 

host of environmental harms, such as visibility impairment and acid rain. 

NACAA commented, as EPA appropriately acknowledges, absent action to reduce 

emissions, by 2020 these engines will contribute more than one quarter (1,352,000 tons) of 

mobile source volatile organic compound (VOC) emissions, nearly a third (16,374,000 tons) of 

mobile source CO, 16 percent (39,000 tons) of mobile source PM2.5 and 4 percent (202,000 tons) 

of mobile source NOx. However, the agency’s proposal, by 2030, will reduce annual emissions 

from affected sources by an estimated 630,000 tons of VOCs, 2.7 million tons of CO, 98,000 

tons of NOx and 6,300 tons of direct PM2.5. Among the quantifiable benefits that would, in turn, 

occur from these reductions is the prevention, annually, of an estimated 450 PM-related 

premature deaths, 500 hospitalizations and 52,000 lost work days. The total annual benefits in 

2030 are estimated at $3.4 billion versus $240 million in annual costs. 

NJ DEP commented that advancing the federal implementation dates would provide more 

timely air quality and health benefits to the residents of New Jersey. Ozone continues to be one 

of the most pervasive air quality problems in New Jersey. The 2002 New Jersey Emissions 

Inventory indicates that approximately 14% of the volatile organic compounds (VOCs) are from 

spark-ignited nonroad engines and equipment rated at 25 horsepower or less. On June 15, 2007, 

New Jersey submitted its proposed State Implementation Plan for the attainment of the 8-hour 

ozone National Ambient Air Quality Standard (NAAQS). It was an enormous challenge to 

develop strategies to reduce ozone in order to meet the 8-hour ozone NAAQS. When the USEPA 

revises the 8-hour ozone standard to be more protective of human health, New Jersey will face 

greater challenges to develop strategies to reduce ozone. Aligning the federal implementation 

dates more closely to the California ARB implementation dates will assist New Jersey in meeting 

these challenges. 

South Coast AQMD commented on the South Coast Air Basin Air Quality Setting. As 

EPA is aware, the South Coast Air Basin (Basin) is designated nonattainment for the federal 

annual PM2.5 and 8-hour ozone ambient air quality standards and must attain these standards by 

2015 and 2024, respectively. To achieve these deadlines, attainment must be demonstrated in the 

preceding years, e.g. 2014 for PM2.5. Compared to the nation’s other nonattainment areas, the 

South Coast Air Basin has the highest population-weighted ozone exposure of any area, 

representing 24 percent of the nation’s 8-hour ozone exposure as well as its highest ozone design 

value. Almost 90 percent of the nation’s total population-weighted exposure to fine particulates 

occurs in California. In addition, 52 percent of the nation’s total exposure to fine particulates 

occurs in the South Coast Air Basin alone. 

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SCAQMD continued that these pollutant exposures result in severe public health impacts 

in the South Coast Air Basin. Numerous studies – conducted locally, nationally and 

internationally – confirm that ozone and particulate pollution have a direct impact on respiratory 

health, increasing asthma attacks, bronchitis, emphysema, chronic obstructive pulmonary 

disease, lung cancer and premature death. For example, studies in Southern California have 

found a significant risk of irreversible decline in lung function among children growing up in 

areas with relatively high particulate pollution. In addition, California ARB has estimated that 

particulate pollution in the Basin causes 5,400 premature deaths, 2,400 hospital admissions, 

140,000 asthma and respiratory symptoms, 980,000 lost workdays, and 5 million restricted 

activity days for minors, every year. 

SCAQMD commented that the region is moving ahead with efforts to attain the federal 8-

hour ozone and annual PM2.5 standards with the recent adoption of the 2007 Air Quality 

Management Plan (AQMP) for the South Coast Air Basin. The attainment challenges are 

significant given that stationary sources are now generally controlled to over 90 percent, and 

about 80 percent of the emissions in the Basin are caused by mobile sources. The attainment 

demonstrations provided in the 2007 AQMP show that the Basin cannot timely attain federal air 

quality standards without significant emission reductions from all sources, including nonroad 

spark-ignited engines. By 2023, pleasure craft will be the third highest VOC emission source 

category in the Basin (about 35 tpd) surpassing passenger cars, petroleum marketing, and 

architectural coating categories. To address this need, as part of the proposed state strategy for 

the California State Implementation Plan, California ARB is proposing new standards for 

outboard/personal watercraft to be implemented in 2013 that will reduce exhaust emissions of 

NOx and VOC by close to 70%. The 2007 AQMP also includes an additional control strategy 

that calls for accelerated turnover of outboard and personal watercraft engines to engines 

meeting the most stringent existing California standards as well as more stringent standards 

adopted in the 2014 timeframe for inboard and stern drive marine engines in order to achieve 

reductions. Achieving the maximum amount of emission reductions from nonroad spark-ignited 

engines is critical to the South Coast Air Basin for meeting the federal 8-hr ozone and annual 

PM2.5 standards. 

NY DEC commented that the ozone forming emissions of the engines targeted by this 

proposal are significant, and occur primarily in the summer ozone season. As EPA notes in 

Section XII-A of the Preamble, recreational marine and small land spark-ignition engines 

account for over a quarter of the national mobile source VOC inventory. The contribution of 

these emissions to ground level ozone formation is even greater because most of the use of these 

engines occurs during the summer ozone season, when most water-borne recreation, lawn and 

landscape maintenance, and outdoor construction takes place. Marine recreation, and the 

associated emissions are also concentrated geographically in areas with suitable waterways. Thus 

the fraction of the national inventory comprised of emissions from these engines likely 

understates their impact on ozone levels and National Ambient Air Quality Standard violations. 

There is clearly a need for the standards proposed by EPA. 

Pennsylvania DEP commented that small land-based, spark-ignition engines and 

equipment and marine spark-ignition engines and vessels contribute significantly to the 

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precursors of ground level ozone. At the existing emissions rates, these engines and equipment 

are expected to contribute as much as 10 to 15 percent of all the volatile organic emissions in 

2009 in the 37 counties in Pennsylvania that are currently designated by EPA as eight-hour 

ozone nonattainment areas. As Pennsylvania and other states face the challenges in attaining and 

maintaining the existing and anticipated more protective ozone National Ambient Air Quality 

Standards and the fine particulate standards, EPA must move forward expeditiously with its full 

complement of controls on new mobile source engines. The projected emission reductions and 

health benefits anticipated by 2030 under this proposal are significant (631,000 tons of volatile 

organic hydrocarbon emissions, 98,200 tons of Nitrogen Oxides emissions, and 6,300 tons of 

direct particulate matter PM2.5 emissions, and 2.69 million tens of carbon monoxide emissions) 

and should, therefore, be achieved expeditiously. 

Houston-Galveston Area Council commented that the Houston-Galveston-Brazoria 

(HGB) region is currently classified as a non-attainment area for the 8-hour ozone National 

Ambient Air Quality Standard (NAAQS). It should be noted that in a letter dated June 15, 2007, 

Texas Governor Rick Perry requested that the HGB region be reclassified as severe 

nonattainment for the 8-hour ozone NAAQS. Additionally, this region is very close to exceeding 

the PM2.5 standard and has elevated levels of air toxics in localized areas. These air quality issues 

result in negative economic impacts, ecosystem damage, negative health effects, and a reduction 

in the quality of life in the HGB area. The unique industrial characteristics of the region 

combined with being one of the largest urbanized population centers in the nation present a 

particularly difficult challenge in terms of improving air quality. Though efforts to improve air 

quality have yielded some progress over the past decade, it is clear that much more needs to be 

done. The active support and participation of the federal government has been vital to air quality 

improvement efforts; however more than half of the ozone-forming pollution in this region is 

generated by mobile sources. Regulation of the emissions from mobile sources is outside the 

authority of individual states such as Texas. 

 Environmental Defense commented that it is well documented that, despite their size, 

spark-ignition (“SI”) marine and small engines contribute significantly to the formation of ozone 

and other harmful air pollutants. EPA estimates that absent the implementation of these 

proposed rules, the emissions from spark-ignition marine and small engines will account for 27% 

of volatile organic hydrocarbon compounds (1,352,000 tons), 31% of carbon monoxide 

(16,374,000 tons), 4% of oxides of nitrogen (202,000 tons) and 16% of particulate matter 

(39,000 tons) from the mobile source sector by 2020. 

Environmental Defense continued to comment that spark-ignition marine and small 

engines contribute to unhealthy air pollution concentrations of ozone, carbon monoxide (CO) 

and PM in numerous areas nationwide. The air pollutants emitted by these engines are associated 

with a host of adverse public health effects including acute respiratory problems, asthma, 

aggravation of cardiovascular conditions and decreased lung function. Acute exposure to CO can 

cause death and non-fatal poisoning. Gaseous vapors that escape from the fuel lines and tanks 

during gas refueling and accidental spills cause and contribute to carcinogenic and noncarcinogenic health problems. Exposure to ozone and particulate matter can cause premature 

death. The immediate final promulgation and implementation of EPA’s proposal will help to 

ensure cleaner air and improved health for millions of Americans. 

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Environmental Defense commented on the following four pollutants: 

A. Ozone 

The SI small and marine engines subject to this proposal consist primarily of lawn and 

garden equipment and recreational boats utilized mostly during the hot summer months. 

As a result, the emissions from these engines play a particularly significant role in the 

formation of ground-level ozone. Ozone is formed by the combination of HC and NOx in 

the presence of heat and light. According to EPA, spark-ignition marine and small 

engines not only produce about one fourth the amount of smog forming HC as all of the 

cars on the road today but their emissions are concentrated during conditions especially 

conducive to ozone formation. California officials report that, on a gallon for gallon 

basis, these engines discharge 93 times more smog forming emissions than model year 

2006 cars. 

Approximately 157 million people are exposed to levels of ozone or “smog” that exceed 

the current national health-based standard. Ozone causes acute respiratory problems, 

asthma, reduced lung function and increased hospital admissions. Children and the 

elderly are most at risk. Recently, a federal advisory panel recommended EPA tighten the 

existing 8-hour ozone health standard due to mounting evidence that it fails to protect 

adequately human health. Scientific studies from the United States and Europe link short 

term increases in ozone levels to increased rates of death from respiratory and 

cardiovascular disease. Day-to-day increases in ozone concentrations during the summer 

have been linked to an increase in premature death. Final promulgation and 

implementation of EPA’s proposal would aid significantly in preventing ozone-related 

illnesses, work absences, and deaths. 

Recent scientific information also demonstrates the harmful effects of ozone on plants 

and ecosystems. According to the EPA, ozone impairs crops, native vegetation, and 

ecosystems “more than any other air pollutant.” Indeed, in examining forest productivity 

and ecosystem diversity, ozone may be the pollutant with the “greatest potential for 

regional-scale forest impacts.” Exposure to ozone weakens plants, making them more 

susceptible to disease, insects and climatic changes. Changes in the biodiversity of plants 

and trees can affect entire ecosystems given the central role vegetation and forests play in 

providing food and habitat for many species of fish, birds and mammals. 

B. Particulate matter 

Spark-ignition marine and small engines are also significant producers of particulate 

matter. PM is a mixture of soot, smoke, and tiny particles due to direct PM as well as PM 

formed in the atmosphere from precursors such as sulfur dioxide, nitrogen oxides, 

ammonia and other pollutants. Scientific studies have shown a statistically significant 

relationship between short term exposure to PM from mobile source emissions and 

mortality. Results from a recent study on the contribution from mobile source emissions 

of PM in 14 U.S. cities indicates that mobile sources, such as the small and marine 

nonroad engines affected by this proposal, have a greater effect on the toxicity of ambient 

air than other sources. 

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Approximately 88 million people across the country are exposed to unhealthy levels of 

PM. Another 27 million are likely to live in areas with unhealthy levels of PM if steps are 

not taken to reduce PM emissions. Exposure to particulate matter can cause acute 

respiratory symptoms, decreased lung function and increased hospital and emergency 

room visits. Exposure to PM has also been linked to death from cardiopulmonary 

disease, premature death, lung cancer and infant mortality. People with heart or lung 

disease, the elderly, and children are most at risk. The proposed standards, if 

implemented, would prevent 460 premature deaths, 52,000 days of missed work, 500 

hospital admissions, and 310,000 restricted-activity days. They would also greatly assist 

states and local governments in attaining or maintaining air pollution concentrations 

below the health-based NAAQS. 

Particulate matter also causes a host of adverse environmental effects. PM impairs 

visibility, both by contributing to local and regional haze. The brown clouds that hang 

over many urban areas and haze surrounding our national parks and wilderness areas are 

caused by particulate matter. Reducing the PM emitted from small and marine engines 

will improve human welfare by helping to reduce these forms of visibility impairment. 

The SO2 and NOx that can transform in the atmosphere to PM also causes atmospheric 

deposition and acid rain. Acid rain is primarily responsible for elevated levels of acid in 

the many fresh-water bodies that dot the U.S. upper- Midwest and Northeast. High 

acidity in lakes and streams alters the chemical composition of the waters, leading to 

changes in vegetation, species loss and contamination. Atmospheric deposition occurs 

when SO2 and NOx deposit into streams, lakes and forest beds. The deposition alters 

water quality and vegetation and can lead to toxic algae and plankton blooms which can 

threaten human health and welfare. Immediate implementation of these standards will go 

a long way in improving human health and welfare and protecting our streams, lakes, 

forests and their inhabitants. 

C. Carbon monoxide 

In 1994 EPA determined that the lawn and garden equipment subject to these proposed 

rules contribute significantly to unhealthy CO concentrations. EPA currently is proposing 

to make a similar determination with respect to CO emissions from SI marine boats. EPA 

estimates that approximately 15 million people live in areas with unhealthy levels of CO. 

Like exposure to ozone and particulate matter, exposure to CO causes a number of 

serious health effects. CO reduces the delivery of oxygen to the body’s organs and is 

associated with impairment of visual perception, work capacity, manual dexterity, 

learning ability and performance of complex tasks. The health threat posed by CO is 

particularly acute for individuals suffering from cardiovascular disease. CO emissions 

also contribute to the formation of ground-level ozone. Exposure to acute levels of CO 

can result in fatal and non-fatal CO poisoning. Between 1984 and 2004 there were 113 

reported deaths and 458 non-fatal poisonings caused by exposure to CO. Recreational 

boaters, inhabitants of house boats, and people swimming around docks are primarily at 

risk of accidental fatal and non-fatal CO poisoning. A number of federal agencies have 

issued health advisories to warn recreational boaters of the serious threats posed by 

exposure to CO. Immediate finalization of the proposed rules will reduce the number of 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

CO-related deaths and illnesses and help to ensure that people living, working, or 

recreating around SI marine boats and vessels can do so safely. 

D. Toxic Air Pollutants 

Gaseous air toxics, such as benzene, 1, 3 butadiene, formaldehyde, acetaldehyde and 

napthalene, comprise another major category of air pollutants emitted by these small 

engines. Exposure to the vaporous air toxics emitted from these engines causes 

carcinogenic and non-carcinogenic health effects. According to EPA’s 1999 NationalScale Air Toxics Assessment, all of the air toxics emitted by these small engines, with the 

sole exception of acetaldehyde, comprise a significant portion of the total inhalation 

cancer risk from mobile sources. Air toxics also cause a number of other serious 

noncancer health problems involving the neurological, cardiovascular, liver, kidney, 

respiratory, immune and reproductive systems. 

One of the air toxics emitted by these small engines, benzene, poses a particularly serious 

threat to human health. Benzene is one of the most significant contributors to cancer risk 

of all air toxics in the ambient air. Assuming continuous exposure to 1999 levels of all 

outdoor air toxics, the nationwide lifetime population cancer risk was 42 per million. 

According to EPA, benzene was responsible for 24% of this cancer risk, and was 

responsible for 42% of the total inhalation cancer risk from mobile source air toxics. 

EPA’s proposal to require more stringent measures to control the toxic evaporative 

emissions from these engines is essential in reducing the cancer, and non-carcinogenic, 

inhalation risk from mobile sources. 

Letters: 

Commenter Document # 

South Coast AQMD 0704 

NJ DEP 0710 

NY DEC 0659 

Houston-Galveston Area Council 0633 

Environmental Defense 0648 

NACAA 0651 

Pennsylvania DEP 0676 

Our Response: 

We agree that emissions from small SI and marine SI engines are significant and often 

occur during the ozone season. The final rule estimates that these engines emit over 2 million 

tons of volatile organic compounds (VOCs) and almost 170,000 tons of NOx annually, and 

contribute to adverse health and welfare effects associated with ozone, PM, NOx, VOCs 

including toxic compounds, and carbon monoxide (CO). Without this rule, emissions from 

Small SI and Marine SI engines, equipment and vessels would continue to grow and would 

become a larger percentage of total mobile source emissions. By 2030 this final rule will reduce 

VOCs by 604,000 tons and NOx by 132,200 tons annually. 

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Chapter 1: Rulemaking Process and Cross-Program Issues 

This rule will help states to reduce air toxics and meet the health and welfare based 

National Ambient Air Quality Standards (NAAQS) for ozone, PM and CO. As of March 12, 

2008 there are approximately 140 million people living in 72 areas designated as nonattainment 

with the 1997 8-hour ozone NAAQS. In addition, approximately 88 million people live in areas 

that are designated as nonattainment for the 1997 PM2.5 NAAQS and 850,000 people live in 

areas that are designated as nonattainment for the CO NAAQS. Both the ozone and PM2.5 

NAAQS have been amended in the last few years and are now more stringent. States with 

nonattainment areas are required to take action to bring those areas into compliance in the future. 

We expect many of the ozone and PM2.5 nonattainment areas will need to adopt additional 

emissions reduction programs to attain and maintain the NAAQS. The emission standards being 

finalized in this action will become effective between 2009 and 2013 and will be useful to states 

in both attaining and maintaining the NAAQS. For discussion on the timing of the standards, see 

Sections 3.2.2, 3.3.2 and 3.4.2 

According to air quality modeling performed in conjunction with this rule, the emissions 

reductions will result in nationwide improvements in ambient ozone concentrations as well as 

decreases in PM2.5 concentrations. By 2030 these reductions will annually prevent 230 PMrelated premature deaths (based on the ACS cohort study), between 77 and 350 ozone-related 

premature deaths (assuming a causal relationship between ozone and mortality), 1,700 hospital 

admissions and emergency room visits, 23,000 work days lost, and approximately 590,000 minor 

restricted-activity days. 

1.15 Other issues 

What Commenters Said: 

OPEI noted that substantial evaporative benefits and exhaust emissions benefits will be 

achieved through the investment of OPEI members to produce Phase 3 compliant products. 

However, OPEI shares the concerns of state organizations and environmental groups, like the 

American Lung Associations and Clean Air Watch, that these air quality benefits and related 

investments could be undermined if EPA approves any new waiver for fuels containing greater 

that 10% ethanol. OPEI commented that EPA must fulfill its statutory obligations under section 

211(f)(4) of the Clean Air Act to carefully review and respond to any waiver for mid-level 

ethanol fuel blends. The 250 million Americans that own and operate over 400 million 

lawnmowers, chainsaws, boats, motorcycles, snowmobiles and automobiles are relying on EPA 

to make sure that neither their products, nor the environment, are damaged through the approval 

of fuels containing greater that 10% ethanol. OPEI also submitted a technical report to EPA to 

highlight the expected adverse impacts of mid-level ethanol blends (see docket item EPA-HQOAR-2004-0008-0746). 

Letters: 

Commenter Document # 

OPEI 0675 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

Although there has been interest expressed by some areas for a mid-level ethanol fuel 

blend (i.e., containing more than the current 10 percent ethanol blend), EPA has not received an 

application for a waiver request at this time. Should EPA receive such a request, EPA would 

fulfill its statutory requirements under the Clean Air Act in responding to the waiver request. It 

can be noted that the recent Energy Independence and Security Act of 2007, revised section 

211(f)(4) of the Clean Air Act. While the basic criteria for analyzing a waiver request stayed the 

same, the revised language states that EPA must also analyze the impact on nonroad engines and 

vehicles. In addition, EPA “must take final action to grant or deny an application submitted 

under this paragraph, after public notice and comment, within 270 days of the receipt of such an 

application.” Prior to the recent change, section 211(f)(4) said the waiver would be treated as 

being granted if EPA did not act within 180 days. 

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2 

Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Exhaust Emission Standards and Related Requirements for Small SI Engines 

What We Proposed: 

The comments in this section generally correspond to Sections V and VII of the preamble 

to the proposed rule, where we describe the proposed emission standards and certification 

procedures associated with exhaust emissions from Small SI engines. The applicable regulatory 

provisions for these proposed requirements are in 40 CFR parts 90 and 1054. The Regulatory 

Impact Analysis describes the feasibility of these standards, special provisions that apply to small 

businesses, and alternative standards under consideration in Chapters 4, 10, and 11, respectively. 

See Chapter 1 of this document for a discussion of issues that apply more broadly than only 

for Small SI engines. See Chapter 4 of this document for a discussion of issues related to 

evaporative emissions. 

2.1 Scope and applicability 

2.1.1 Definition of handheld 

What Commenters Said: 

OPEI commented that EPA appears to have two definitions of handheld indicated in 

1054.101(c) and 1054.801. In order to prevent the unintended reclassification of these products 

in 1054.801, OPEI commented that EPA should keep the newly proposed weight limits intact but 

make a revision to the definition of a handheld engine in 1054.801 by adding paragraph (6) Is 

used in a portable hand-supported jackhammer/rammer, compactor (vibratory or other) or other 

similar product. As an alternative, EPA could add a statement to the definition in 1054.801 

indicating all engines/product less than 80cc are automatically handheld regardless of weight etc. 

OPEI also commented that paragraph (4) of the definition should be revised to eliminate “oneperson” since many augers using handheld engines can be operated by two-persons. 

EMA commented that the NPRM properly categorizes equipment utilizing engines less 

than or equal to 80cc total displacement as “handheld.” The NPRM also correctly categorizes 

equipment utilizing engines with larger than 80cc total displacement, but also meeting additional 

requirements, as eligible for categorization as handheld. Such engines should be allowed to 

continue to meet handheld exhaust standards, and should be considered handheld 

engines/equipment for purposes of the new evaporative standard requirements. In addition, 

equipment that EPA has historically approved as meeting the definition of “handheld,” such as 

compactors/rammers, should be allowed to continue to be categorized as handheld and should be 

specifically included in the regulation in order to ensure that all industry and agency personnel 

are aware of the appropriate determining factors. 

EMA submitted comments on EPA’s proposal to modify the handheld definition by 

increasing each of the specified weight limits by 1 kilogram (72 FR at 28141). EMA agrees that 

an adjustment is required. However, they commented that the proposed adjustment is 

insufficient for the conversion of prior emission control engines to either catalyzed two-cycle 

2-1 
Chapter 2: Small SI Engines 

engines or four-cycle engines, as required to achieve exhaust emission standards. EMA 

recommended that the handheld definition be adjusted by increasing each of the specified weight 

limits by 2 kilograms. 

The California Air Resources Board (CARB) believes categorizing handheld equipment 

is best done by engine size such as the 80cc limit set by California. This gives the engine 

manufacturers an emissions design target at the beginning of the process. To the extent EPA 

believes it necessary to maintain the handheld category above 80cc, CARB supports the change 

in weight limits for handheld equipment. CARB commented that the increase of one kilogram, 

representing the approximate additional weight related to switching to a four-stroke engine, is an 

appropriate adjustment. 

Honda submitted comments in agreement with EPA’s proposal that would allow engines 

less than 80cc to comply with both handheld exhaust and evaporative emission standards. 

Honda commented that the language on evaporative emissions should be clarified to include 

these engines. Additionally, Honda commented that engines above 80cc could then use the 

equipment-based handheld definitions to quality for the handheld category. Honda 

recommended that EPA specifically add earth rammers to the handheld category rather than 

continuing to rely on the Phase 2 guidance that they qualify as handheld products. Finally, with 

the direct inclusion of 0 to 80cc engines in the handheld emission category, Honda believes the 

proposal’s definition for handheld equipment should be given careful reconsideration. This may 

be particularly true for products with weight limits of 14 or 20kg. Honda questioned whether it 

is necessary for generators and pumps less than 14kg (15 kg proposed) to be considered 

handheld by definition. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

CARB 0682 

Honda 0705 

Our Response: 

EPA does not believe the regulations contain two different definitions of handheld. The 

EPA regulations define “handheld” in §1054.801 by specifying the criteria that are to be used to 

determine if an equipment application is handheld and therefore subject to the various handheld 

requirements of Part 1054. Section 1054.101 describes which exhaust standards apply to the 

different types of engines. Paragraph (a) notes that all handheld engines (i.e., those that meet the 

definition in §1054.801) must meet the handheld exhaust standards. In addition, paragraph (c) 

notes that all engines at or below 80cc will be subject to the handheld engine standards, 

regardless of the type of application the engine is ultimately placed in. The provision in 

paragraph (c) does not mean the engine is a handheld engine. It only means that the engine is 

subject to the handheld exhaust standards. Therefore, EPA believes both of the regulatory 

provisions noted above are necessary and have been retained in the final rule. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

In response to the comment on the 80cc cutpoint, EPA cannot use 80cc as the only 

criteria for whether an engine is subject to the handheld exhaust standards because there are 

many products that use engines above 80cc which qualify under the criteria contained in the 

handheld definition of §1054.801. CARB uses the 80cc cutpoint in its regulations. However, 

CARB’s regulations do not apply to those products above 80cc considered handheld under 

EPA’s definition due to the construction and farm equipment pre-emption provisions of section 

209(e) of the Clean Air Act. Therefore, EPA is retaining a definition of “handheld” in the final 

rule. 

It should be noted that the proposal based the cutpoint for the applicability of the 

handheld provisions on engines “less than” 80cc. As noted in the proposal, this change was 

intended to harmonize with the displacement-based requirements for CARB. During 

development of the final rule, it came to EPA’s attention that the CARB cutpoint is based on 

engines “at or below” 80cc. EPA has modified the final rule regulations to include this approach 

so that the EPA and CARB requirements are the same. 

With regard to the comments on hand-supported jackhammers, rammers and compactors, 

EPA agrees that the definition of handheld should include a specific reference to such 

applications. In response to requests from equipment manufacturers in the past, EPA has 

approved the manufacturers’ request to consider such applications as handheld based on the 

criteria spelled out in the handheld definition on multi-position use. Therefore, EPA believes it 

makes sense to include the hand-supported jackhammers, rammers, and compactor applications 

specifically in the handheld definition. 

With regard to the comment on augers, EPA is removing the “one-person” term from the 

auger description in the handheld definition. EPA acknowledges that some augers can be 

operated by two people, but still have other attributes that would lead to the equipment being 

considered a handheld application, including the dry weight of the equipment. Therefore, EPA 

believes the “one-person” terminology is not needed with respect to augers. 

In response to the comments on whether a special provision for pumps and generators is 

needed given the requirement that all engines at or below 80cc can meet the handheld standards, 

EPA investigated the current certification information to see how many engines above 80cc are 

used exclusively in pumps and generator applications that would fall under the 15 kilogram 

weight limit (engine and equipment combined) included in the proposed definition. While EPA 

was able to identify a few engine model used in such applications, sales of such engines were 

extremely low. EPA sees no technical reason why such applications would need to use engines 

certified to the handheld standards and is therefore removing the pump and generator language 

from the handheld definition in §1054.801 of the regulations 

In response to the comments on the proposed weight limits in the handheld definition, 

EPA looked at similar equipment applications in which the engine is similarly sized, but 

powered by either a 4-stroke engine or a 2-stroke engine. Based on an analysis of similarly 

designed string trimmers, the dry weight of a 4-stroke trimmer with a 25 cc engine was 

advertised at 13 pounds, whereas the dry weight of two different 2-stroke trimmers with similar 

sized engines (24.5cc and 28cc) was advertised at 9.5 and 10.6 pounds. Therefore the 2-stroke 

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Chapter 2: Small SI Engines 

trimmers were 3.5 and 2.4 pounds (1.6 and 1.1 kilograms) lighter than the 4-stroke trimmer. 

Based on this comparison, EPA agrees that it is reasonable to raise the weight limits in the 

handheld definition by 2 kilograms instead of the proposed 1 kilogram increase to account for 

the increased weight of switching to a 4-stroke engine. Therefore, EPA is adopting a 16 

kilogram weight limit in the handheld definition for most equipment with a 22 kilogram weight 

limit for augers. 

Finally, with regard to Honda’s comments that the language on evaporative emissions 

should be clarified to include all engines at or below 80cc under the handheld evaporative 

requirements, EPA agrees in principle. For the purposes of the exhaust emission standards, 

engines at or below 80cc are subject to the handheld exhaust standards. Under the new 

regulations, equipment manufacturers are allowed to use engines at or below 80cc in either 

handheld or nonhandheld equipment. Because the applicability of the evaporative emission 

standards is based on the type equipment, an engine at or below 80cc used in a nonhandheld 

piece of equipment (that is subject to the handheld exhaust standards) would be subject to the 

nonhandheld equipment evaporative standards. EPA believes this could be difficult, especially 

with regard to running loss requirements that apply to nonhandheld equipment but not handheld 

equipment. Therefore, the final regulations require nonhandheld equipment to comply with the 

nonhandheld evaporative emission standards unless it is using an engine at or below 80cc. In 

that case, the equipment manufacturer would need to demonstrate compliance with both the fuel 

line and fuel tank requirements in 2012. The running loss requirement would not apply to 

nonhandheld equipment using engines at or below 80cc. (It can be noted that EPA is adopting a 

similar provision for nonhandheld engines which are used in handheld equipment. In such a case 

the equipment would be subject to the handheld evaporative emission standards which do not 

require control of running losses. The fuel line and fuel tank requirements would apply and take 

effect in 2012.) 

2.1.2 Small SI vs. Large SI 

What Commenters Said: 

EMA noted that the current differentiation between Small SI and Large SI nonroad 

engines is principally determined based on the power of the engine (e.g., less than or equal to 19 

kW). In addition, engine manufacturers have the discretion to categorize engines that have 

power greater than 19 kW, but less than or equal to 30 kW, with total engine displacement less 

than or equal to 1,000 cc, as Small SI engines. The current differentiation should not be 

changed. 

EMA noted that the NPRM introduces restrictions regarding total engine displacement 

through the addition of one significant figure to the displacement determination, and provides a 

clarification stating that all engines produced must be included in the displacement 

determination. Such clarification requires that all production tolerances be included in the 

determination of maximum production displacement. EMA commented that the regulatory 

requirements should be clarified in order to avoid confusion regarding the product category 

applicability, and the final rule should include the proposed clarification that all engines, 

including tolerances, must be within a category. However, the proposed additional significant 

2-4 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

figure for representation of engine displacement is not necessary. In fact, the addition of such 

significant figure may result in unintended consequences associated with engine designs that are 

currently classified as Small SI. Accordingly, EMA commented that EPA should not require that 

engine displacement be calculated to an additional significant figure. 

EMA noted that §90.116(a) requires the total engine displacement to be rounded to the 

nearest whole cubic centimeter, but paragraph (g) requires the total displacement to be rounded 

to the nearest 0.1 cc. EMA suggested that §90.116(g) be revised to reflect the nearest whole 

cubic centimeter as required by §90.116(a). 

EMA commented on §1054.615(b) “What is the exemption for engines certified to 

standards for Large SI engines?” EMA noted paragraph (b) refers to paragraph (f) of the same 

section, however the section does not include a paragraph (f). EMA believes the correct 

reference should be to paragraph (d). 

Kohler noted that EPA is proposing to modify the criteria used to determine the 

displacement for the large SI one liter exemption. Kohler commented that it is opposed to this 

change. Kohler provided comments on specific sections in the proposed regulations. They noted 

that §90.116(g) has been added which limits the displacement of each engine produced to 1000.0 

cc after rounding to the nearest 0.1 cc. This is a change to the previous requirement of 

calculating displacement using nominal engine values and rounded to the nearest whole cubic 

centimeter. This changes the rules established in §1048.6l5(a)(l) and 90.l 16(a) after the 

regulations have been implemented. Kohler requested that the previous wording be retained. If 

it is not, any engine families certified to the current Part 90 wording should be grandfathered and 

this change should not take effect until the Phase 3 regulation is implemented in 2011. Kohler 

noted that §1054.140(d) limits the displacement of each engine produced to 1000.0 after 

rounding to the nearest 0.1 cc. This is a change to the previous requirement of calculating 

displacement using nominal engine values and rounded to the nearest whole cubic centimeter. 

Kohler doesn’t believe this change is justified and requested the current wording in Part 90.116 

be retained. 

Letters: 

Commenter Document # 

EMA 0691 

Kohler 0703 

Our Response: 

 We agree with the commenters’ position that the differentiation between Small SI and 

Large SI engines should not be changed, and specifically that the 1000 cc threshold should not 

be changed to 1000.0. If we had done this originally, manufacturers could have easily planned 

for that and taken steps to ensure that nominal engine dimensions and production tolerances were 

adequately controlled to stay below the threshold. Since we did not adopt the more precise 

threshold, manufacturers have in good faith designed their engines consistent with the 

regulations as published. We do not believe there is a sufficient environmental benefit 

corresponding to the more precisely defined threshold to justify the costs associated with 

modifying engine designs in this way. 

2-5 
Chapter 2: Small SI Engines 

The concern related to ensuring that every engine is below the threshold comes from the 

realization that we might have had a difficult time establishing that there was a violation if the 

manufacturer had declared a nominal value that was below the threshold, even though production 

variability could arguably lead to substantially higher displacement values. In the context of 

highway motorcycles that are subject to different standards if they are over 50 cc, we have seen 

examples of wide variations in displacement values above 50 cc where the manufacturer claimed 

to be in compliance with regulatory requirements. Kohler has pointed out that their particular 

situation involves production variability that would be problematic if the threshold were 1000.0 

cc, but not if the threshold were 1000 cc. We are modifying the regulatory language to specify 

that the declared displacement value must be within the range of actual values for production 

engines, taking into account normal production variability. This approach is similar to what we 

specify for declaring maximum engine power in §1054.140. This should allow us to 

meaningfully implement and enforce the 1000-cc threshold without changing the meaning of the 

current regulations for those who are already complying in good faith. 

We have modified the regulation language to more clearly state that engines voluntarily 

certified to the exhaust emission standards for Large SI engines in part 1048 are also subject to 

evaporative emission standards under part 1048. Since Large SI evaporative requirements fall to 

the engine manufacturer, there should not be a situation where an equipment manufacturer 

becomes subject to EPA standards because of the engine manufacturer’s choice to certify to 

more stringent exhaust emission standards. In fact, equipment manufacturers may in the end 

meet evaporative requirements for Small SI engines (especially for running loss control) even 

though they don’t need to. This would not be a violation. We believe this regulatory 

arrangement represents the clearest and most natural division of responsibilities among the 

affected companies. 

2.1.3 Maximum engine power and displacement 

What Commenters Said: 

EMA believes the NPRM introduces significant additional complexities with respect to 

the determination of maximum power. EMA commented that the final rule should clarify that 

the power reported by the engine manufacturer may appropriately be determined utilizing the 

engine manufacturer’s good engineering judgment and the appropriate industry standard for 

power measurement. 

EMA commented on §1054.140 “What is my engine’s maximum engine power and 

displacement?” EMA believes the proposed language is both excessive and incomplete. 

Specifically, they commented that the requirement to map engines pursuant to 40 CFR Part 1065 

is not appropriate for small air cooled Small SI engines, and the maximum engine power does 

not specify a rating procedure. The proposed requirement to include all engines in the 

displacement determination, as well as including the additional significant figure to the 

displacement reporting is not appropriate. EMA believes this section should include only those 

requirements that are significant to the determination of whether an engine family should be 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

classified as a Small or Large SI engine. Accordingly, EMA commented that this section should 

be revised to read as follows: 

(a) An engine configuration’s maximum power is the power level assigned by the engine 

manufacturer as determined using an industry standard power measurement procedure. 

Engine families where the maximum modal power of the emission-data engine is greater 

than 15 kW at the test speed designated require manufacturers to include the brake power 

for engines in the certification application for the family as prescribed by 1054.205. 

(b) An engine configuration’s displacement is the intended swept volume of all the 

engine’s cylinders. The swept volume of the engine is the maximum product of the cross 

section area of the cylinder bore, the stroke length, and the number of cylinders including 

all tolerances. Determine the final value by rounding the final result to the nearest 1 cc. 

(c) Deleted in its entirety. 

(e) Deleted in its entirety. 

EMA noted that §1054.1(a)(1) states that the requirements of Part 1054 apply to engines 

with “maximum engine power at or below 19kW.” EMA commented that it is not clear what 

type of power level is being described. As the definitions set forth in §1054.801 include a 

definition of “brake power,” EMA commented that §1054.1(a)(1) should be revised to read as 

follows: “maximum engine brake power at or below 19kW.” 

OPEI noted that EPA explains in 1054.205(a) that this section only applies if the engine 

is 15 kW or greater. OPEI commented that the language of §1054.140 should be modified to 

explain it is not applicable to engines less than 15 kW or less than 0.95 liters. 

Kohler noted that §1054.801 defines “Displacement” to have the meaning given in 

1054.140, which is changed from the current provisions in §90.116. Kohler commented that the 

current meaning in §90.116 should be retained. Kohler also objected to the extensive reporting 

and recordkeeping requirements in the proposed rule. One of the items Kohler noted was the 

requirement to report maximum engine power in the application for certification. 

Letters: 

Commenter Document # 

EMA 0691 

OPEI 0675 

Kohler 0703 

Our Response: 

Appropriately defining terms to establish an engine’s displacement and maximum engine 

power are important for ensuring that the regulations specify objectively and consistently which 

emission regulations apply. Every engine should be unambiguously subject to a single set of 

emission regulations—there should be no overlaps or gaps. For maximum engine power, the 

regulations need to differentiate Small SI engines from Large SI engines (and in some cases from 

recreational vehicle engines). For displacement, the regulations need to assign each engine to a 

Class for determining which standards apply under part 1054. EMA accurately summarizes our 

2-7 
Chapter 2: Small SI Engines 

objective by stating that we should “include only those requirements that are significant to the 

determination of whether an engine family should be classified as a Small or Large SI engine.” 

Part 90 in particular does not include such procedures and specifications for establishing 

clear and objective determinations of power and displacement. We have chosen to adopt the new 

approach in part 1054 in combination with the Phase 3 standards rather than introducing these 

regulatory provisions as amendment to the Phase 2 program in part 1054. Such a change could 

cause unintended consequences by forcing an engine to be subject to a different set of standards 

even though we are intending to leave the current standards intact. 

To accomplish this, the regulations must use consistent and objective parameters for 

making these determinations. It would not be appropriate to rely on a manufacturer’s judgment 

in establishing maximum engine power, because it would be impossible to ensure a proper 

delineation between Small SI and Large SI engines. Without an objective specification or 

procedure, manufacturers would be free to manipulate the declared value to choose the less 

stringent standards. Both maximum engine power and displacement can be measured using 

standard procedures and specifications, so we believe the regulation should rely on these 

procedures and specifications to determine those values. 

While engine mapping is not required to test Small SI engines, we believe it is entirely 

appropriate to do engine mapping for engines where there is a need to demonstrate that the 

engine’s power falls within the specifications for regulation as a Small SI engine. Mapping 

procedures are specified in part 1065. This measurement can be readily made when an engine is 

mounted on an engine dynamometer. The specified mapping procedure and the instructions for 

determining maximum engine power constitute a complete rating procedure for these engines. 

This may be different than the manufacturers’ current practice, but it is a rating procedure 

nonetheless. 

We specify that the power and displacement values determined under §1054.140 fall 

within the range of actual values from production engines. Any departure from this would 

clearly be inappropriate, since the production engines clearly would not be appropriately 

represented by those values determined during the certification process. We describe in Section 

2.1.2 how we specify displacement limits relative to the 1000 cc threshold for Large SI engines. 

The regulations use consistent and appropriate terminology to characterize maximum 

engine power. Brake power is a separately defined term to clarify which accessory loads are 

properly counted toward any measured power value. The regulations in §1054.140 simply 

specify that maximum engine power is the maximum value of an engine’s measured brake power 

over an engine map. 

It would not be appropriate to limit the applicability of §1054.140. This section 

establishes definitions and specifications that dictate how the regulations apply. These 

definitions apply universally, but by themselves they require no action. Other regulatory 

provisions, such as the requirements to report maximum engine power in §1054.205, determine 

whether action is required to make a demonstration. 

2-8 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

We proposed to require manufacturers to report their maximum engine power for engines 

with a measured power at or above 15 kW under the specified emission test procedure. This was 

intended to require this reporting only as needed to ensure that engines were not exceeding 19 

kW based on the proposed approach to defining maximum engine power. We believe we can 

more carefully craft this provision, given the 30 kW threshold that applies for engines with total 

displacement at or below 1000 cc. As a result, we are modifying the regulation to require 

reporting of maximum engine power only where the maximum power for testing is at or above 

25 kW for engines with total displacement at or below 1000 cc, and above 15 kW for larger 

engines. 

2.1.4 General concerns 

What Commenters Said: 

J. Snell would like to urge EPA to leave small engines exempt from emission controls. 

The commenter believes it would raise the price of items like lawn mowers, pressure washers 

and go karts which do not have a large enough impact on the environment to justify this increase 

especially in rural areas. The commenter stated EPA could at least consider a horsepower or a 

cubic centimeter limit. The commenter also believes that 4 cycle motorcycles should also be 

exempt for they are a tiny percentage of the machines in the world that put out emissions. 

Letters: 

Commenter Document # 

J. Snell 0623 

Our Response: 

The Clean Air Act directs us to set emission standards for nonroad engines, including all 

Small SI engines, such that we achieve that greatest degree of emission control possible after 

considering lead time, costs, and other factors. We have made an extensive effort to set 

standards that are achievable with costs that are commensurate with the air quality benefit 

associated with the reduced emissions. We are not changing the emission standards that apply 

for highway motorcycles. 

2.2 Standards and lead time 

2.2.1 NHH standards–level 

What Commenters Said: 

EMA noted that they were an active participant in the development of the NPRM for the 

next-phase Small SI engine standards. EMA commented that the net result of that collaborative 

process is an NPRM that truly and properly reflects the maximum achievable emission 

reductions for Small SI engines and the equipment that they power. EMA commented that the 

rulemaking has set forth extremely challenging and dramatic, but nonetheless potentially 

2-9 
Chapter 2: Small SI Engines 

achievable, emission reduction targets. Indeed, EMA believes the effort that has gone into this 

collaborative rulemaking has resulted in the promulgation of an overall framework of 

technology-forcing standards and accompanying regulations that are at the very limit of 

feasibility and implementability. As a consequence, EMA commented that the overall 

framework needs to be maintained in the final rule, since any potential increased stringency of 

the proposed standards or the overall regulatory program would necessarily result in an 

infeasible and non-implementable rule. 

EMA commented that exhaust emission control technologies for ground supported Small 

SI engines are similar to, but cannot be derived from, other nonroad engine applications or onhighway applications. Ground supported Small SI engines and the equipment that they power 

operate under significantly different environmental and cost considerations. Such considerations 

pose major obstacles to any wholesale transfer of advanced exhaust emission control systems 

and necessarily prevent the fuel and exhaust control technologies used in on-highway (or even 

nonroad large spark-ignition) from being applicable to these products. 

MECA commented that it supports EPA harmonizing HC+NOx exhaust emission 

standards for Class I and Class II engines used chiefly on nonhandheld equipment with the 

CARB standards that were adopted in 2003 and began their implementation in 2007. MECA 

also concurs with the EPA staff analysis and conclusion that the proposed Phase 3 HC+NOx 

exhaust emission standards for Class I and Class II engines are technologically feasible and that 

catalyst technology can be fully optimized as part of a complete engine/emission control/exhaust 

system to help achieve these proposed limits. 

MECA noted that both EPA and CARB test programs have shown that catalysts can be 

applied to Class I and Class II engines without increasing safety risks associated with exhaust 

component surface temperatures. Integration of catalyst into small engine mufflers utilizes 

uncomplicated manufacturing techniques that should allow for the design and validation of 

compliant engines within the lead-time provided by the EPA regulations. The 30 years of 

catalyst experience in general and the over 10 years of experience with applying catalysts to 

smaller SI on-highway and nonroad engines provide an experience base that has enabled catalyst 

technology to continue to be improved. This small engine experience has provided an increased 

understanding of how to optimize the engine/catalyst/exhaust system to work effectively, and 

will facilitate application of catalyst technology on Class I and Class II engines to help meet the 

proposed standards. 

MECA commented that issues raised by small off-road engine and equipment 

manufacturers, such as heat management, packaging, poisoning, and durability, are 

straightforward engineering challenges that are well understood and can be readily addressed. 

They noted that these types of issues have been raised virtually every time the use of catalyst 

technology has been proposed for use on a spark-ignition engine, be it an automobile, heavy 

truck, off-road engine over 25 hp (such as a forklift), a motorcycle or moped, or a small engine 

used on handheld or non-handheld equipment. In each case, all of these issues were successfully 

addressed for each application through sound engineering principles and design strategies. 

MECA believes the situation is no different in the case of Class I and Class II nonroad engines. 

2-10 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

CARB supported the HC+NOx exhaust emission standard levels proposed by EPA. 

NESCAUM supported EPA’s effort to harmonize the federal emissions standards with 

those standards already adopted in California. In many respects, the proposed federal standards 

are identical to or analogous with California standards. This approach will make it easier for the 

engine and equipment manufacturers to provide 50-state products to the U.S. market. 

Environmental Defense supported EPA’s proposal to set more stringent HC and NOx 

standards for Class I and II nonhandheld small spark-ignition engines and a new CO standard for 

use in marine generator applications. These Phase III standards can be met by the use of 

catalysts, improved engine or fuel delivery systems, or the addition of electronic controls or fuelinjection systems. According to EPA, several engine families selling nationwide currently 

produce engines that meet the proposed Phase III standards. Therefore, “a number of families 

either will not need to do anything or will require only modest reductions” in order to comport 

with the new federal standards. The proposed standards are consistent with those previously 

adopted by CARB. Once in place, EPA’s proposal should achieve emissions reductions of 

approximately 35% below the current federal levels. 

The National Association of Clean Air Agencies (NACAA) commented that it supports 

the federal adoption of exhaust emission standards for small spark-ignition engines consistent 

with those adopted by the California Air Resources Board. Based on the EPA’s March 2006 

safety study and the Regulatory Impact Analysis for this proposal, as well as public statements 

by engine makers, it is evident that additional, more stringent emission standards are feasible for 

small spark-ignition engines, especially commercial equipment, which operates hundreds, if not 

thousands of hours a year. Therefore, NACAA recommended that EPA consider adding another 

tier of more rigorous standards for Class I and Class II engines. 

The Pennsylvania Department of Environmental Protection (DEP) commented that it 

supports EPA’s adoption of a regulation for small spark-ignition engines and equipment that is 

consistent with regulations adopted by the CARB. Consistent with EPA’s findings set forth in 

the March 2006 Safety Study and the Regulatory Impact Analysis for the proposed rulemaking, 

the Pennsylvania DEP recommended that EPA add a tier of more stringent standards for Class I 

and Class II engines. 

The Mid-America Regional Council (MARC) Air Quality Forum commented that 

because EPA and small engine manufacturers have both asserted that Class I and II engines can 

be feasibly designed to meet emissions standards more rigorous than those in the proposed rule, 

EPA should consider incorporating an additional tier of more stringent standards. 

The Wisconsin Department of Natural Resources (DNR) commented that EPA should 

consider adding another tier of more rigorous emission standards for Class I and Class II sparkignition engines as more stringent emission standards are feasible for these engines, especially 

commercial equipment, which operate hundreds, if not thousand of hours a year. 

The New York Department of Environmental Conservation (DEC) noted that EPA is 

proposing standards similar to existing California standards for small spark-ignition engines. 

2-11 
Chapter 2: Small SI Engines 

The proposed standards, to be implemented in 2011 and 2012, will result in a 35% reduction in 

combined hydrocarbon and NOx emissions for engines in non-handheld equipment. The New 

York DEC noted that it is well aware of industry opposition to these proposed regulations, and 

supports expedient adoption of the standards as proposed. They also believe that further 

emissions reductions are needed, and will be feasible in the future. 

Environmental Control Corporation (EVCC), a developer of catalytic mufflers for small 

spark-ignition engines (both two-stroke and four-stroke) commented that their technology has 

proven HC+NOx reductions of up to 98.9% on a two-stroke engine and 90% on a four-stroke 

engine while also significantly reducing CO. They noted that they are in full support of the 

current regulations, but they encouraged EPA to set even more stringent standards in the near 

future. 

EVCC provided information on their catalytic mufflers. First, EVCC noted that its 

patented catalytic muffler is linearly designed and can be modified to fit virtually any sparkignition engine. EVCC has successfully completed emissions testing for a variety of engine 

applications (both two-stroke and four-stroke), including lawn mowers, snowmobiles, out-board 

motors, water-pumps, and more. The company just recently completed a durability test on a 163 

cc four-stroke engine (in compliance with EPA and CARB certification parameters), and is 

currently in the process of completing durability testing for a two-stroke application. Second, 

EVCC noted that its catalytic mufflers are both cost-effective and compact in size. The unique 

airflow design of these mufflers allows them to achieve unprecedented emission reductions while 

using minimal materials and space. In its most recent 163cc four-stroke test (lawn-mower 

application), EVCC noted that its catalytic muffler was smaller than that of the OEM and did not 

require external air, baffles, perforated pipes or sound chambers. 

EVCC noted that it is very concerned that EPA plans to continue regulating the emissions 

of small non-road engines by grouping HC and NOx together as one value. EVCC commented 

that manufacturers of four-stroke spark-ignition engines (i.e. lawn and garden equipment) are 

able meet both current and future emission regulations for CO and HC+NOx by engine 

modifications and minor carburetor calibrations (by running the engine on a lean fuel mixture, 

for example). While EVCC believes these engine modifications and minor carburetor 

calibrations will reduce CO and HC, in most instances there will be a concomitant increase in 

NOx. This is highly undesirable, as increases in NOx will have a drastic impact on both human 

health and the environment. 

EVCC noted that the emission regulations in which HC and NOx are combined together 

for a total emission certification value permits an increase in NOx levels as a trade-off to 

reducing HC. This loop-hole is completely unnecessary in the small engine sector, as three-way 

catalytic converters are fully capable of reducing all three emission values simultaneously. In 

addition, NOx is one of the most harmful by-products of fossil-fuel combustion, and 

manufacturers should by no-means be permitted to increase NOx levels needlessly. All three of 

the emission values in question are individually regulated in the automotive sector, and it is now 

time to carry this practice to the small engine industry. 

2-12 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Frank Smith, a retired Chemistry Professor from the Memorial University of 

Newfoundland, commented that in changing the emission regulations applicable to small sparkignition engines, the requirements should be set such that the technology exists to achieve the 

levels selected. In that respect, the ability of catalytic mufflers developed by Environmental 

Control Corporation (EVCC) should be seriously considered. These devices have been tested 

both at Environment Canada’s test facility and at Carnot Emission Services establishment. In 

January 2007, at the latter facility, results over an extended test of 125 hours, achieved for a fourstroke engine (Honda GX-160), included NOx emissions of less than 0.5 g/kW-hr, HC emissions 

of less than 5 g/kW-hr, and CO emissions of less than 300 g/kW-hr of operation, without 

reduction of performance. 

In the same tests the combined HC+NOx emissions were also less than 5 g/kW-hr. 

Consequently, for all pollutants considered the emissions were well below those of current 

CARB regulations and also those proposed by EPA. In June 2006, tests of EVCC’s catalytic 

muffler fitted to a two-stroke 185 cc Class I nonhandheld engine at Environment Canada’s test 

facility gave similarly low emissions of all three pollutants. A six-mode test (in accordance with 

US EPA and CARB regulations) using 20 LPM of air injection in the catalyst was conducted by 

officials at Environment Canada. Of particular interest is the 99 % reduction achieved in 

hydrocarbon emissions from around 250 g/kW-hr with the original muffler to 2.5 g/kW-hr with 

the catalytic muffler. This data strongly suggests that control of all three pollutants separately is 

feasible at levels below those currently proposed. 

Letters: 

Commenter Document # 

EMA 0691 

MECA 0668 

CARB 0682 

NESCAUM 0641 

Environmental Defense 0648 

NACAA 0651 

Pennsylvania DEP 0676 

MARC AQ Forum 0696 

Wisconsin DNR 0663 

NY DEC 0659 

EVCC 0608 

EVCC 0654 

F. Smith 0694 

Our Response: 

 Section 213(a)(3) of the Clean Air Act specifies the criteria EPA must use in establishing 

new emission standards. Under the statute, EPA is directed to set emission standards that 

achieve the greatest degree of emission reduction achievable through the application of 

technology which EPA determines will be available for the engines or vehicles to which such 

standards apply, giving appropriate consideration to the cost of applying such technology within 

the period of time available to manufacturers and to noise, energy, and safety factors associated 

2-13 
Chapter 2: Small SI Engines 

with the application of such technology. In addition, and specific to this rulemaking only, under 

section 205 of PL 109-54, EPA, in coordination with other appropriate federal agencies, was 

required to complete and publish a technical study analyzing the potential safety issues 

associated with the proposed standards, including the risk of fire and burn to consumers in use. 

The technical study was to be completed and published before the publication of the notice of 

proposed rulemaking. Given these criteria and requirements and our assessment of the 

comments, EPA continues to believe that the proposed Phase 3 standards are the appropriate 

standards for nonhandheld engines for the years in which they were proposed for 

implementation. (See Section 2.2.2 for further discussion of the comments on lead time for the 

Phase 3 nonhandheld engine standards.) 

The Phase 3 standards for nonhandheld engines are technology forcing and are expected 

to result in the use of modified calibrations, engine improvements, catalysts, and fuel injection to 

achieve the required emission reductions. The mix of technologies will vary depending on the 

engine design. As detailed in Chapter 4 of the Final RIA, EPA developed several aftertreatment 

and fuel-injection systems to demonstrate that the Phase 3 standards could be met. In addition, 

EPA assessed the impacts of the new standards on cost as detailed in Chapter 6 of the Final RIA. 

Finally, EPA expended considerable effort in analyzing the potential safety impacts of engines 

designed to meet the proposed Phase 3 standards to comply with the requirements of section 205 

of PL 109-54. (“EPA Technical Study on the Safety of Emission Controls for Nonroad SparkIgnition Engines < 50 Horsepower,” EPA420-R-06-006, March 2006, docket item EPA-HQOAR-2004-0008-0333.) Taking all of this information into consideration, EPA believes the 

Phase 3 standards meet the criteria specified in the Clean Air Act for the time frame in which the 

standards are to be implemented. 

EPA received several comments that we should set more stringent standards than those 

being adopted today, but we do not concur. All of these commenters except one (as noted 

below) provided no supporting analysis or data on any of the relevant statutory factors in support 

of their request. One commenter did submit emission data showing very low emission levels for 

a Class I engine. In fact, EPA itself generated emissions data for the proposal showing low 

levels as well. For example, in Class I, EPA tested a number of engines that had HC+NOx 

emission levels as low as 3.9 g/kW-hr at low hours and were projected to be as low as 5.7 g/kWhr HC+NOx at the end of their regulatory useful life. Likewise, for Class II engines, EPA tested 

engines with HC+NOx emission levels as low as 1.8 g/kW-hr at low hours and projected to be as 

low as 2.3 g/kW-hr at the end of their regulatory useful life. (All of the emissions data generated 

by EPA and summarized here, is presented in Chapter 4 of the Final RIA.) However, as noted 

above, the requirements for establishing new emission standards are dependent on more than 

demonstrating certain emission levels. So while EPA had its own emission data showing lower 

emission levels are achievable, EPA determined for the proposal that under section 213(a)(3) of 

the CAA, the Class I standard of 10.0 g/kW-hr HC+NOx and the Class II standard of 8.0 g/kWhr HC+NOx were the appropriate emission standards. Section V.G. of the proposed preamble 

and Chapter 4 of the Draft RIA for the proposed rule laid out EPA’s assessment of the proposed 

standards in the context of all of the CAA criteria. As noted above, none of the commenters 

asking for more stringent standards addressed these other factors. 

2-14 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

In addition, in Chapter 11 of the draft RIA for the proposed rule, for both Class I and 

Class II engines, EPA considered the appropriateness of more stringent emission standards (i.e., 

8.0 g/kW-hr HC+NOx for Class I engines and 4.0 g/kW-hr HC+NOx for Class II engines) based 

on the CAA criteria. EPA noted that while more stringent standards may be feasible, EPA 

concluded that more leadtime would be required for such standards. This was based on the fact 

that more stringent standards would require more fundamental and significant changes in engine 

design in both Classes I and II. For Class I engines, we projected that manufacturers would 

likely need to convert their side valve engine designs (which represent two-thirds of sales 

currently) to overhead valve designs along with using a more efficient catalyst and addressing 

emissions deterioration. For Class II engines, we projected that manufacturers would need to 

convert all engines to fuel injection, upgrade their residential engine designs to improve 

emissions deterioration characteristics (e.g., those with a 250 hour useful life), and use a more 

efficient catalyst. Such redesigns would involve significantly more development work for all 

manufacturers (and likely more cost) compared to the changes projected for the Phase 3 

standards adopted in this rule. This could not happen as soon as the 2011 and 2012 timeframe 

being adopted for the Phase 3 standards, and would result in a delay in achieving air quality 

benefits. 

In further response to comments that EPA should have promulgated more stringent 

standards than we proposed, it is important to note that setting more stringent standards for either 

Class I or Class II or both, would require a more robust analytical record. Those suggesting that 

more stringent standards should be established now (either in a single or two phases) did not 

provide input on factors such as cost, lead time, and the other CAA criteria for public 

consideration. EPA could have pursued such further analysis at this time, but it would likely 

have required an additional notice/comment step which would further delay this action. The 

states with air quality problems would benefit more from the earlier reductions due to the 

standards being adopted in this final rule rather than waiting for further reductions. Therefore, 

EPA concluded that the proposed Phase 3 standards (which we are adopting with today’s rule) 

are the appropriate standards under the CAA. 

With regard to the comment on having separate HC and NOx standards instead of a 

combined HC+NOx standard, EPA is retaining the standards based on a combined HC+NOx 

level as is the case with the current Phase 2 standards. EPA believes a combined standard offers 

flexibility to manufacturers in designing technology to comply with the standards, especially 

since not all engine designs respond identically to the same control techniques in catalyst design 

where it is generally easier to reduce HC emissions compared to NOx emissions. While it is true 

that mathematically a combined standard could result in a decrease in overall HC+NOx 

emissions with a rise in NOx (or HC), EPA does not expect that would happen to any significant 

degree as manufacturers redesign engines to comply with the Phase 3 standards. This is 

especially true if a manufacturer uses a catalyst to comply with the Phase 3 standards because a 

catalyst would be expected to reduce both HC and NOx, although not at the same rate. This also 

would likely be true for those engines that might rely on engine modifications to comply with the 

Phase 3 standards. The latter conclusion is based on a comparison of three 2008 model year 

Class II engine families that have certification levels below the Phase 3 standards compared to 

similarly sized Phase 2 engines from the same manufacturer. For this comparison, all of the 

engines were OHV engines and were certified without catalysts. In all three cases, the overall 

2-15 
Chapter 2: Small SI Engines 

HC+NOx emissions for the 2008 model year engines were lower by up to 27 percent, and the 

individual HC levels and NOx levels were also lower. While most of the decrease in HC+NOx 

emissions was from decreases in HC emissions, the NOx emissions decreased in all cases as 

well. Therefore, while a combined HC+NOx standard has the potential to lead to higher levels 

of one pollutant relative to that pollutants level under the Phase 2 requirements, EPA believes 

that the Phase 3 HC+NOx standards should also result in lower HC emissions and lower NOx 

emissions for the fleet. 

Additionally, it should be noted that the Phase 3 standards being adopted by EPA are the 

same as those adopted by CARB, which are based on the combined HC+NOx level. Having the 

same requirements as CARB helps manufacturers by allowing them to certify the same designs 

with both agencies, which might not be possible if EPA were to adopt separate HC and NOx 

standards. In addition, it is important to note that the further control of HC and NOx emissions 

from these engines is being driven by the need to reduce ambient ozone concentrations. Both HC 

and NOx contribute to the formation of tropospheric ozone, so a slight mix in the relative 

reductions among engine designs does not deter achieving the ozone air quality improvement 

goal which is a key basis for this action. 

2.2.2 NHH standards–lead time 

What Commenters Said: 

OPEI commented that under Section 213 of the Clean Air Act, EPA must make sure that 

adequate lead-time is provided to allow all equipment manufacturers, as well as their separate 

engine and exhaust system suppliers, to develop and test the new materials, technologies, and 

safeguards, including low-permeation fuel tanks and catalyzed-exhaust systems, and to ensure 

operational risks are mitigated under all the expected operating conditions including off-nominal 

conditions. As long as they are provided with adequate lead-time and the other related 

flexibilities, OPEI noted that its members will be able to design their products to utilize catalyzed 

exhaust systems that would be required to meet the proposed EPA Phase 3 standards. OPEI 

provided a number of reasons why any acceleration of the proposed Phase 3 effective dates or 

dilution of the proposed lead-time flexibilities would undermine and potentially jeopardize the 

manufacturers’ ability to build and test products to ensure they would not have any incremental 

risks. 

First, the inclusion of aftertreatment systems into an equipment manufacturer’s exhaust 

system will require a much broader set of changes than just packaging the catalyst into an 

existing muffler, as implied by the EPA in the proposed Preamble discussion. Second, nonintegrated equipment manufacturers must work closely with a variety of suppliers to design and 

install all the different components into the final product. Third, it will take an extraordinary 

amount of time and effort to develop a single piece of equipment with an effective and safe 

catalyzed muffler that has been thoroughly evaluated – under both nominal and off-nominal 

conditions. Fourth, given the volumes and diversity of these Class II exhaust systems, and 

limited resources, OEMs are concerned that there will be several bottlenecks (with all their 

suppliers, independent test labs, and certification officials) that will further delay the production 

and certification process. Fifth, most of the non-integrated equipment manufacturers expect they 

2-16 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

will be forced to offer only limited CARB, Tier III-compliant products for the California market. 

The national market will require the industry to address many of the most challenging muffler 

applications and configuration that will not be offered in California. 

MECA commented that EPA’s proposal to implement the exhaust emission standards for 

Class I and Class II engines in the 2011-2012 timeframe provides more than adequate lead time 

for engine and equipment manufacturers. MECA urged EPA not to push out these 

implementation dates beyond the proposed 2011 and 2012 dates. MECA believes that an even 

faster implementation schedule for these exhaust emission standards is feasible given the 

implementation schedule adopted by California. 

CARB commented that they believe the timing of the new standards should be 

implemented sooner. Small spark-ignition engine manufacturers have already been preparing to 

meet the California standards which are the same as EPA’s proposed standards. The 

manufacturers already have the technological ability to meet the standards. Under EPA’s current 

proposal, manufacturers of Class II engines will have three years from the time California 

standards have gone into effect and Class I engine manufacturers have five years. It should not 

take these manufacturers three to five additional years to meet these standards nationwide, 

particularly since EPA also allows for credit generation which gives manufacturers additional 

flexibility. CARB suggested that an alternative would be for EPA to give the manufacturers that 

do not currently sell their products in California extra time to meet the standards. 

CARB recommended that EPA modify its proposed HC+NOx phase-in schedule for large 

spark-ignition engines ≤ 1 L to harmonize with the California small off-road engine exhaust 

emission standards for Class II engines, 8 g/kW-hr at the 2008 model year. This would provide 

for significant emission reductions from this category. Furthermore, a harmonized program 

would help reduce the problem of higher emission 49-state large spark-ignition engines traveling 

into the California fleet. 

NACAA questioned the need for the substantial additional lead time that EPA has 

proposed beyond the implementation dates enacted by California – five years (until 2012) for 

Class I engines and three years (until 2011) for Class II engines. They believe an accelerated 

federal schedule is technically feasible and recommended that EPA give consideration to more 

rapid implementation. 

Pennsylvania DEP commented that they are concerned about the need for the substantial 

additional lead-time of three to five years proposed by EPA and strongly suggests more rapid 

implementation to afford greater protection of human health and the environment. 

The MARC AQ Forum noted that the proposal sets implementation deadlines 2012 for 

Class I engines and 2011 for Class II engines. They urged EPA to accelerate its implementation 

timeline. 

NESCAUM commented that they oppose the protracted timelines for compliance with 

the standards, proposed for manufacturers of small land-based SI engines and equipment. The 

analogous California exhaust emissions standards are fully phased-in between 2005 and 2008. In 

2-17 
Chapter 2: Small SI Engines 

contrast, the proposed phase-in period for the proposed federal standards does not even begin 

until 2010 and, with special provisions afforded to small to medium volume manufacturers, full 

compliance is delayed until as late as 2014. NESCAUM does not believe there are valid reasons 

for delaying the incorporation of Phase 3 engines into various types of equipment nationally 

when manufacturers will already be supplying the California market with lower-emitting Phase 

III engines and equipment years earlier. This approach for protracted delays is inconsistent with 

the approach taken in the same rulemaking for SD/I marine engines where EPA chose to closely 

track effective dates for the California standards: “EPA is proposing that the Federal SD/I 

standards take effect for the 2009 model year, one year after the same standards apply in 

California. We believe a requirement to extend the California standards nationwide after a oneyear delay allows manufacturers adequate time to incorporate catalysts across the product lines 

as they are doing in California. Once the technology is developed for use in California, it would 

be available for use nationwide soon thereafter.” NESCAUM requested that the exhaust 

emission standards for land-based small SI engines be fully implemented, beginning with the 

2009 model year, consistent with the proposed compliance dates for SD/I engine standards. 

Wisconsin DNR commented that EPA should accelerate the implementation dates of the 

exhaust emission standards for Class I and Class II small spark-ignition engines consistent with 

those adopted by CARB. 

NJ DEP noted that the CARB standards for exhaust emissions are fully phased-in 

between 2005 and 2008, whereas the proposed phase-in dates for the corresponding federal 

standards do not begin until 2010. Of most concern, NJ DEP highlighted the special provisions 

for small and medium manufacturers which may delay full compliance until 2014. In light of the 

fact that manufacturers will already be providing cleaner engines and equipment to California 

and that technology issues will not be a factor, these cleaner engines and equipment should be 

required to be made available sooner nationwide. 

Environmental Defense commented that they object to the much delayed implementation 

dates for these important standards. EPA’s proposed engine exhaust limits for nonhandheld 

Class I and Class II engines do not go into effect until model year 2012 and 2011 respectively, 

while California’s comparable standards take effect in 2008 and 2009. In justifying the proposed 

near-term implementation dates for SD/I and OB/PWC standards, EPA relies on the fact that 

many manufacturers currently design and sell cleaner engines capable of achieving the proposed 

standards. Environmental Defense agrees with EPA that the availability of cleaner technology 

weighs in favor of near-term implementation dates since the cost and burden to manufacturers in 

meeting a more stringent standard is low in this instance. For this reason, they fail to understand 

why EPA has reached such a different conclusion in setting the implementation dates for the 

small SI engine exhaust standards. Technological advances in the SI small market, just like 

those in the SI marine sector, have resulted in the wide-spread availability of cleaner engines 

capable of achieving greater emissions reductions. In addition, EPA’s proposal provides small 

SI engine manufacturers with substantial flexibility by allowing them to choose from a number 

of aftertreatment technologies in order meet the new standards. The breadth of available 

technologies capable of reducing small engine emissions to the proposed Phase 3 levels weighs 

in favor of shorter implementation dates, not longer. EPA’s failure to explain adequately its 

2-18 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

basis for delaying the implementation dates by some 4-5 years is arbitrary and capricious and 

contrary to law. 

Mr. Dan Holland commented that he opposes delaying immediate and full 

implementation of the proposed rules. He believes that requiring water craft to comply with the 

new standards in 2009 but not require "land-based" small engines to comply until 2011 is 

arbitrary and capricious. There is no need -- or excuse -- to wait until 2011 to implement the new 

regulations with respect to all new small engines. He believes that proven technology is 

commercially available now that can make all new small engines compliant with the more 

stringent, proposed regulations that the EPA is authorized to promulgate. Delaying 

implementation of the new standards with respect to new land-based small engines until 2011 

can only be interpreted as “political” bias in favor of the Senator from Missouri that has long 

opposed emissions regulation and emissions reduction on the specious grounds that the addition 

of catalytic converters etc. cause small engines to run “hot” and/or cause external fires, both of 

which studies by the EPA and others have disproved. Substantial emissions reductions can 

readily and easily be achieved by adding existing, proven, inexpensive technologies to new 

engines, and this wait-until-2011 “free pass” for land-based engines is simply unacceptable, and 

it is legally indefensible in light of Congress's mandate in section 428(b) of the 2004 

Consolidated Appropriations Act and existing Section 213(a)(3) of the Clean Air Act which 

contemplates an immediate business response during a 12-month business-design cycle, not a 

business cycle "four years from now." 

Letters: 

Commenter Document # 

OPEI 0675 

MECA 0668 

CARB 0682 

NACAA 0651 

Pennsylvania DEP 0676 

MARC AQ Forum 0696 

NESCAUM 0641 

Wisconsin DNR 0663 

NJ DEP 0710 

Environmental Defense 0648 

D. Holland 0595 

Our Response: 

EPA continues to believe that the proposed Phase 3 standards are the appropriate 

standards for nonhandheld engines for the years in which they were proposed. (See Section 2.2.1 

for further discussion of the comments on the level of the standard for the Phase 3 nonhandheld 

engine standards.) As noted above, EPA believes the new Phase 3 standards for nonhandheld 

engines are technology forcing and are expected to result in the use of technologies including 

engine improvements, catalysts, and fuel injection to achieve the required emission reductions. 

Engine manufacturers will need substantial time to redesign all of their engine families to 

comply with the new standards. 

2-19 
Chapter 2: Small SI Engines 

A look at the current certification data for the 2008 model year provides useful 

information to gauge the level of effort required by engine manufacturers to comply with the 

new standards. (EPA’s certification data can be found on the internet at the following site: 

http://www.epa.gov/otaq/certdata.htm#smallsi ) There are a total of 87 manufacturers with 

nonhandheld engine families certified with EPA. For the following discussion, we have focused 

on the 15 manufacturers that historically have been selling in the small engine market. (The 

remaining 62 manufacturers, primarily from China, are recent participants in the small engine 

market and generally have only 1 to 5 engine families certified with EPA with relatively low 

sales volumes.) For these 15 manufacturers of nonhandheld engines, there are currently 66 

engine families certified in Class I and 121 engine families certified in Class II. (These numbers 

exclude engines used exclusively in snowblowers which do not have to comply with the 

HC+NOx standards). While some of these engine families have emission levels below the Phase 

3 standards, manufacturers will need to redesign the bulk of the designs to meet the Phase 3 

standards. For these 15 manufacturers, EPA estimates that 53 of the Class I engines and 83 of 

the Class II engines will have to be redesigned to meet the Phase 3 standards. (“Analysis of 

2008 Small SI Nonhandheld Engine Certification Data,” EPA memo from Phil Carlson to EPA 

Docket OAR-2005-0008, August 28, 2008, docket item EPA-HQ-OAR-2004-0008-____.) 

For the six manufacturers with the highest numbers of nonhandheld engine families (i.e., 

Briggs and Stratton, Fuji Heavy Industries, Honda Motor Company, Kawasaki Heavy Industries, 

Kohler Company, and Tecumseh Products Company), EPA estimates that they will need to 

redesign over 19 engines families, on average, to comply with the new Phase 3 standards. (The 

range in the number of engine families needing to be redesigned for these manufacturers is from 

12 to 35 engine families.) Given that we are finalizing the Phase 3 standards in late-2008, 

manufacturers will have only 2 years before the Class II engine standards take effect and 3 years 

before the Class I engine standards take effect. As described below, we believe that engine 

redesign will require a significant level of effort for engine manufacturers. Given the level effort 

needed and the number of engine families needing to be redesigned, EPA does not believe it 

would be possible to reduce the lead time for the new standards. 

The Phase 3 emission standards for Class I engines are expected to result in engine 

improvements and the use of catalysts. Catalysts have been implemented on few of these 

engines to date and therefore the expected widespread use will require significant technology 

development and investment from engine manufacturers. In addition to the catalyst brick 

formulation, other technology requirements include muffler design for desired pollutant 

conversion (which they will want to optimize for minimum precious metal loading to reduce 

costs), consideration of regulatory useful life emission requirements, addressing cooling 

requirements related to muffler skin temperature and exhaust temperature, and testing of the 

engines in real-world applications. While EPA believes the technological challenges can be met 

by manufacturers, each of these steps will take considerable resources and time to address for 

each of their engine families. As noted in Chapter 6 of the Final RIA (as well as Chapter 6 of the 

Draft RIA for the proposal), EPA estimates that engine modifications will take 4 months of 

design work and 6 months of development work for each engine design. In addition, EPA 

estimates that applying catalysts will take 2 months of design work and 5 months of development 

work for each engine design. 

2-20 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Likewise, the Phase 3 emission standards for Class II engines are expected to result in 

both engine redesign and the application of catalysts on many engines. For those Class II 

engines using catalysts, engine manufacturers will need to address the same issues noted above 

for Class I engines. In addition, they will need to communicate closely with their Class II engine 

users (i.e., equipment/vehicle manufacturers) since most Class II engines are sold without an 

exhaust system. Due to the wide number of exhaust systems used on these engines, equipment 

manufacturers will either have to modify the existing equipment design to utilize a manufacturer 

provided muffler, or they will have to develop their own muffler using the engine manufacturer’s 

provided catalyst brick specifications and then do the certification of that engine. Although EPA 

believes these issues can be addressed, all of these efforts will take time. As noted in Chapter 6 

of the Final RIA (as well as Chapter 6 of the Draft RIA for the proposal), EPA estimates that 

engine modifications will take 4 months of design work and 6 months of development work for 

each engine design. In addition, EPA estimates that applying catalysts will take 2 months of 

design work and 5 months of development work for each engine design. 

Finally, under the Phase 3 program, EPA is requiring the certification of engines using 

new test procedures under part 1065 by the 2013 model year. These new procedures require 

engine manufacturers to implement changes to their current test setup in order to incorporate new 

test cell operation procedures and new emissions calculations. If a manufacturer is going to 

spend the resources to certify a new engine, they will likely want to do it only once so as to use 

the carryover data option in certification for a number of years. Therefore, it is likely 

manufacturers will want to certify in 2011 or 2012 with the new procedures. The effort it will 

take to convert manufacturer’s facilities depends on the age of the manufacturer’s current testing 

equipment and will add to the time and effort required to comply with the new Phase 3 standards. 

Given the number of engine families that need to be redesigned, the types of 

technological issues that will need to be addressed for each engine family, and the new test 

procedure requirements to which manufacturers will need to convert, EPA believes the 2012 

requirement for Class I and 2011 requirement for Class II are the appropriate leadtime for the 

new standards. 

With regard to the comments that EPA should move up the implementation dates because 

California’s Tier 3 standards are already in effect, an analysis of the 2008 model year 

certification data from CARB for the six engine manufacturers with the highest number of 

nonhandheld engine families (as noted above) provides some useful information. While 

CARB’s Tier 3 standard for Class I engines took effect in 2007, only 9 out of 29 engine families 

are certified by these manufacturers at or below the 10.0 g/kW-hr HC+NOx standard. For Class 

II engines, where the Tier 3 standard takes effect in 2008, only 19 out of 60 engine families are 

certified by these manufacturers at or below the 8.0 g/kW-hr HC+NOx standard. While these 

manufacturers have redesigned some of their engines to meet CARB’s Tier 3 standards, they are 

using emission credits to certify the remaining engines. Therefore, even though CARB’s Tier 3 

standards are already in effect, manufacturers have a significant amount of work to finish 

certifying their engines for California. We continue to believe the Phase 3 implementation dates 

of 2012 for Class I and 2011 for Class II provide the appropriate leadtime for manufacturers to 

redesign their engines to comply with EPA’s Phase 3 standards. 

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Chapter 2: Small SI Engines 

2.2.3 CO standard for marine generators 

What Commenters Said: 

MECA supported EPA’s proposal to establish a Phase 3 CO standard of 5 g/kW-hr for 

marine generators. They noted that existing commercial applications of catalyst-equipped 

marine generators provide strong evidence that EPA’s proposed low CO standard for marine 

generators is technically feasible. 

EMA commented that dedicated marine generator engines that are permanently installed 

into vessels (such that they can take advantage of features such as water cooling, vessel DC 

electrical systems, electronic closed loop feedback fuel control systems, and three way catalyst 

aftertreatment systems) may be able to comply with the proposed CO emission standard (5 

g/kW-hr). However, many auxiliary marine engines are either not dedicated to the vessel or are 

not integrated in a manner consistent with the technology that would be required in order to 

achieve the proposed CO emission level. Accordingly, EMA commented that the final 

regulation must clarify that the proposed CO standard is only applicable to the fully-integrated 

marine generator engines described in the NPRM. 

Letters: 

Commenter Document # 

MECA 0668 

EMA 0691 

Our Response: 

 We agree with EMA that marine auxiliary engines that are not generators should not be 

subject to the more stringent CO standard. This was reflected in the proposed rule. We do not 

believe it is appropriate to specify some degree of integration for marine generators before the 

more stringent standards apply. This information is generally not available to engine 

manufacturers at the point of certification and it would be difficult to specify an objective 

measure that would make this enforceable. The final regulation is unchanged, requiring all 

marine generators to meet the 5 g/kW-hr CO standard. 

2.2.4 Useful life 

What Commenters Said: 

EMA noted that there are a wide variety of usage patterns for the engines and equipment 

governed by the proposed regulation. EMA commented that the proposed maximum time span 

of 5 years for the emission durability period is acceptable provided that the final rule clearly 

states that the durability period is the lesser of either hours or years. 

OPEI commented that the last line of the useful life definition, “If an engine has no hour 

meter, the specified number of hours does not limit the period during which an engine is required 

2-22 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

to comply with emission standards...” should be deleted. OPEI supported a 5 year time limit on 

useful life. This means the specified number of hours or 5 years (whichever comes first). 

CARB believes that it is appropriate to limit the useful life period to five years or the 

specified number of operating hours, whichever comes first. Limiting the useful life period 

would be favorable to both industry and regulatory agencies. It would allow manufacturers to 

limit warranty coverage by a time period rather than operating hours which can be difficult to 

determine. For regulatory agencies, it provides more flexibility in limiting the length of time 

credits may be used. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

EMA 0691 

Our Response: 

 All the commenters supported the provision that would define the useful life period as 

five years or a specified number of hours of engine operation, whichever occurs first. We are 

therefore adopting this provision, including a clear statement that either one of these two age 

indicators would be sufficient to establish the end of the useful life. 

The last sentence in the definition of useful life clarifies how to apply the definition with 

respect to hours of operation if the engine has no hour meter. Leaving out this specification 

would leave this ambiguous and would require that we make a judgment in guidance to the 

industry. We believe it is therefore fitting to include this clarification in the regulation. 

Moreover, we believe the proposed provision establishes a very reasonable approach, such that 

the hours-based limit on useful life is meaningful only if the extent of operation can be 

established without the missing hour meter. For example, if an engine is certified based on a 

useful life of 250 hours, we would intend to be able to do in-use testing on such engines that 

have been in service in consumer use in a riding lawnmower throughout the five-year period 

representing the useful life, unless it is clear that the engine has operated for more than 250 hours 

(if, for example, the lawnmower has been used in commercial service long enough to 

demonstrate that it has operated longer than 250 hours. 

See Section 2.4.2 for additional discussion related to selection of useful life values for 

certification. 

2.2.5 Crankcase controls 

What Commenters Said: 

EMA commented on §1054.115(a)(1)(i) “What other requirements apply?” EMA noted 

that the section states that engines must be manufactured in a way to allow crankcase emissions 

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Chapter 2: Small SI Engines 

to be routed into the emission measurement sampling system. EMA commented that it is 

impractical for an engine manufacturer to meet this requirement given the diversity of exhaust 

emission measurement equipment. This requirement should be revised to replace the testing 

requirement with an engineering judgment/test requirement as described in §90.109. 

EMA commented on §1054.115(a)(1)(ii) “What other requirements apply?” EMA 

commented that because the exhaust emission measurements utilized to determine the 

deterioration factor must include the crankcase emissions pursuant to §1054.115(a)(1), this 

section’s requirement to include deterioration in crankcase emissions in the determination of 

deterioration factors is illogical. However, if the requirement in §1054.115(a)(1)(i) is revised to 

incorporate the language from §90.109 (as suggested above), then this section would not require 

any additional revisions. 

Letters: 

Commenter Document # 

EMA 0691 

Our Response: 

 It is unclear on what basis manufacturers should be using good engineering judgment 

regarding an engine’s ability to meet emission standards considering vented crankcase emissions 

if those emissions cannot be measured. We believe emission-measurement systems should be 

capable of measuring crankcase emissions where a manufacturer would want to make a separate 

measurement of crankcase emissions for adding to the conventional emission results. This is 

especially true in the case of dilute testing. However, regardless of the method used to measure 

emissions, we allow for a test setup in which the engine is modified such that the crankcase 

emissions are vented into the exhaust before sampling. This should be readily achievable for any 

system that can make a valid exhaust emission measurement with Small SI engines. 

We find it entirely logical to consider measured changes in crankcase emissions over an 

engine’s service life in the determination of deterioration factors. The effect of changing 

crankcase emissions could be quantified separately (if crankcase emissions are measured 

separately) or the manufacturer could use a single deterioration factor that combines the 

crankcase and conventional exhaust emissions at all points. 

2.2.6 Safety 

What Commenters Said: 

OPEI commented that the ability of manufacturers to produce and accurately evaluate the 

potential hazards of any new technology, including catalyzed mufflers, depends on EPA 

providing adequate lead-time and all the related proposed flexibilities. There will be substantial 

development work and costs associated with the development and installation of heat-shielding, 

and other safeguards to ensure that catalyzed exhaust systems (at the efficiency levels discussed 

in the proposal) do not pose any increased risks or hazards. As EPA's administrative record 

demonstrates, any more stringent exhaust standards, or more accelerated effective dates (than 

2-24 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

those EPA has proposed) would not meet that statutory requirements in Section 213 of the Clean 

Air Act, including feasibility, safety, lead-time, and costs. 

OPEI continued that the industry is becoming much better informed on how to build and 

evaluate catalyzed products primarily as a result of the continued research and development 

work internally conducted by manufacturers. Manufacturers are also becoming better informed 

on the exhaust gas temperatures and the muffler surface temperatures (where grass clippings and 

other debris could potentially ignite) through the comprehensive study that was released this 

spring by the National Institute of Standards and Technology (NIST). Manufacturers will 

become more knowledgeable through the current related study on the heat-related challenges of 

catalyzed mufflers that has been conducted by the SP Technical Research Institute of Sweden for 

the International Consortium for Fire, Safety, Health and the Environment (ICFSHE). The OPEI 

Education and Research Foundation funded both the NIST and SP studies in order to promote 

our understanding of the heat-related challenges with both catalyzed and non-catalyzed mufflers 

so that manufacturers can build even safer products that respond to these challenges. From 

OPEI’s perspective, the NIST and SP studies are solely intended to inform manufacturers as they 

develop new ANSI standards for “Mitigation Of Heat-Related Hazards From Mufflers On All 

Ground-Supported Equipment”. For example, the SP study will ultimately help manufacturers 

develop procedures (to mimic in their laboratories) the most challenging and complex offnominal conditions (such as single spark-plug misfire or malfunction on a twin cylinder engine). 

The EPA and SP studies (as well as manufacturers’ current experience in California) also 

generally confirm the enormous challenges and lead-time needed to design, build and internally 

evaluate all their diverse catalyzed equipment to ensure these products will be durable, emissioncompliant and minimize the risks under the complex, nominal and off-nominal operating 

conditions. 

OPEI commented that while there is still much work that remains to be done, OPEI 

members are working with all their different suppliers to develop catalyzed products and to draft 

and finalize the new, helpful ANSI standards. The smaller OEMs (with the least internal staff 

and resources) will benefit the most from the information supplied in the ANSI process. ANSI 

standards development is a voluntary consensus-based process. The actual time to develop a 

standard varies based upon the iterative notice and comment procedures. The ANSI committee 

is currently on track to develop the final ANSI standards before the Phase 3-exhaust standards 

are proposed to become effective in 2011. 

OPEI stated that EPA’s proposed exhaust standards combined with the proposed 

effective dates should allow time for the entire industry to build catalyzed products that do not 

increase any risks. The proposed effective dates should allow time for the new ANSI standards 

to be finalized and issued to the public before the Phase 3 exhaust standards begin to apply. 

MECA concurred with the conclusions reached by EPA staff that the application of 

catalysts to nonroad equipment or marine generators with either Class I or Class II spark-ignited 

engines can be accomplished using available engineering exhaust system design principles in a 

manner that does not increase the safety risk relative to today’s uncontrolled equipment. In 

particular, the EPA safety study on non-handheld equipment equipped with catalyzed mufflers 

represents the most thorough safety study completed to date on this class of spark-ignited 

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Chapter 2: Small SI Engines 

engines. The results of this EPA study showed that properly designed catalyzed mufflers pose 

no incremental increase in safety risk (and in many cases even lower muffler surface 

temperatures) relative to currently available non-handheld equipment sold without catalysts. 

Catalysts have also been used voluntarily on lawn mowers in certain European markets since the 

late 1990s and on a range of handheld equipment with no significant, reported safety issues, 

providing additional support that catalysts can be integrated into the mufflers of Class I and 

Class II engines in a safe manner. 

During testimony at the public hearing, Mr. Richter of Heraeus noted that they have 

supplied catalysts for European “green” products in response to certain European states that have 

requirements for catalyst-based systems on some of their walk behind equipment. Mr. Richter 

noted that nearly a million walk behind mowers have been produced with a catalyst in Europe in 

response to these requirements. When asked if he was aware of any problems, performance 

issues or anything related to use of the catalysts, Mr. Richer responded that there were none 

whatsoever. 

Letters: 

Commenter Document # 

OPEI 0675 

MECA 0668 

Heraeus (hearing) 0642 

Our Response: 

Section 213 of the Clean Air Act directs us to consider the potential impacts on safety, 

noise, and energy when establishing the feasibility of emission standards for nonroad engines. 

Furthermore, section 205 of EPA’s 2006 Appropriations Act requires us to assess potential safety 

issues, including the risk of fire and burn to consumers in use, associated with the new emission 

standards for nonroad spark-ignition engines below 50 horsepower. We expect that the new 

exhaust and evaporative emission standards will have no adverse affect on safety. 

In response to industry comment that proposed exhaust standards combined with the 

proposed effective dates should allow time for the entire industry to build catalyzed products that 

do not increase any risks, we are finalizing the proposed standards in the years in which they 

were proposed. Given that we are finalizing the Phase 3 standards in mid-2008, manufacturers 

will have a little over two years to redesign their Class II engines and a little over three years to 

redesign their Class I engines. 

The safety analysis performed by EPA for Class I and II engines and SP Technical 

Research Institute for Class II engines both indicate that the addition of catalyst technology can 

be safely implemented with the proper design strategies. Both of these studies are available in 

the docket. (“EPA Technical Study on the Safety of Emission Controls for Nonroad SparkIgnition Engines < 50 Horsepower,” EPA420-R-06-006, March 2006, docket item EPA-HQOAR-2004-0008-0333.) (“Scientific Evaluation of the Risk Associated with Heightened 

Environmental Requirements on Outdoor Power Equipment - Phase II,” SP Technical Research 

Institute of Sweden, docket item EPA-HQ-OAR-2004-0008-711.1.) In addition, a detailed 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

analysis of both studies is included in a Memo to Docket EPA-HQ-OAR-2004-0008 titled 

“Nonhandheld SI Exhaust System Safety Analysis.” 

The scope of our safety study included Class I and Class II engine systems that are used 

in residential walk-behind and ride-on lawn mower applications, respectively. We conducted the 

technical study of the incremental risk on several fronts. First, working with CPSC, we 

evaluated their reports and databases and other outside sources to identify in-use situations that 

create fire or burn risk for consumers. From this information, we identified ten scenarios for 

evaluation covering a comprehensive variety of in-use conditions or circumstances that could 

lead to an increased risk of fire or burn. Second, we conducted extensive laboratory and field 

testing of both current technology (Phase 2) and prototype catalyst-equipped advancedtechnology engines and equipment (Phase 3) to assess the emission control performance and 

thermal characteristics of the engines and equipment. Third, we conducted a design and process 

Failure Mode and Effects Analyses (FMEA) comparing current Phase 2 and Phase 3 compliant 

engines and equipment to evaluate incremental changes in risk probability as a way of evaluating 

the incremental risk of upgrading Phase 2 engines to meet Phase 3 emission standards. 

Our technical work and subsequent analysis of all the data and information strongly 

indicate that effective catalyst-based standards can be implemented without an incremental 

increase in the risk of fire or burn to the consumer either during or after using the equipment. 

2.2.7 Altitude 

What Commenters Said: 

OPEI recognized that altitude provisions for handheld engines are controlled by 

§1054.145(c)(4). This paragraph specifies that handheld engines must meet applicable emission 

requirements up to an altitude of 1100 feet (96 kPa). Kit information should be supplied in the 

operator’s manual and application for certification. Handheld engines are small, compact and 

also cannot bear the cost of automatic altitude compensation systems. Such engines also run 

under high thermal and mechanical load, which make them sensitive to increased air-fuel ratio 

that would follow having to comply with the emissions standard also at high altitude settings. In 

general, A/F ratio changes as a function of the square root of the air density/fuel density. This 

may vary based on unique engine characteristics. Depending on a manufacturer’s compliance 

margin and production line auditing values, OPEI believes the 1100-foot (96 kPa) requirement 

should be acceptable. 

OPEI supported the proposed requirement that altitude kits must be available for nonhandheld products sold in geographic locations with higher altitudes. They believe the 

prescribed ambient pressure limitation for determination of compliance is acceptable and more 

appropriate than the referenced altitude. The manufacturer’s ability to demonstrate compliance 

with the prescribed exhaust emission standard levels at atmospheric pressures lower than 94.0 

kPa should utilize a combination of historical information, engineering analysis, and good 

engineering judgment in the determination of altitude kit information to be included in the engine 

family certification application and owner’s manual. OPEI commented that the regulatory 

requirements should be minimized in order to continue to allow the various manufacturer 

processes that have and will continue to provide this service to their respective customers. 

2-27 
Chapter 2: Small SI Engines 

EMA supported the proposed requirement that altitude kits must be available for products 

sold in geographic locations with higher altitudes. The prescribed ambient pressure limitation 

for determination of compliance is acceptable, and a more appropriate metric than using actual 

altitude. However, EMA commented that the manufacturer should be allowed to demonstrate 

compliance with the prescribed exhaust emission standard levels at atmospheric pressures lower 

than 94.0 kPa utilizing altitude kit information included in the engine family certification 

application and owner’s manual. Altitude kit design should be determined using a combination 

of historical information, engineering analysis, and good engineering judgment. EPA should 

minimize the regulatory requirements in order to continue to allow the various manufacturer 

processes that have and will continue to provide this service to their respective customers. 

EMA noted that engine manufacturers can (and do) provide the necessary parts and 

training for modification of products that are used in high-altitude conditions. Customers that 

operate equipment in high-altitude areas are well aware of the need for these modifications. In 

order for these provisions to be viable, EPA must allow a means for the manufacturer to provide 

these altitude kits to consumers (dealer network, distribution system, etc.). However, EMA 

believes that the owner’s manual information should be limited to altitude effects that owners 

will understand. Specifically, the owner’s manual should include information that would inform 

the consumer that engines operated at altitudes greater than the manufacturer prescribed 

minimum may require the engine/equipment to be modified in order to ensure proper operation. 

The owner’s manual also should instruct the consumer to contact the engine manufacturer for 

further information. In addition, the information provided to the ultimate customer must identify 

the range of altitude the product is expected to operate in, the applicable engine specifics 

required to determine the appropriate altitude kit, and where the customer can either obtain the 

required kit or have the kit installed. 

EMA commented on §1054.115(c) “What other requirements apply?” EMA commented 

that the reference to 40 CFR Part 1065.520 should clarify that the specified barometric pressure 

range of 94.0 to 103.325 kPa is an exception rather than an additional requirement. Further, 

EMA commented that the meaning of the reference to a “standard configuration” is unclear. 

Accordingly, the language should be revised to read as follows: “Engines must meet the 

applicable emission standards for valid tests conducted under the ambient conditions specified in 

40 CFR Part 1065.520 except using a barometric pressure range from 94.0 to 103.325 kPa. This 

requirement is applicable to nonhandheld engines distributed to all areas that do not exceed 2000 

feet in elevation above sea level. See §1054.145(c) for handheld engine provisions. For higher 

altitude distribution, and resulting lower barometric pressures, carburetor modifications by the 

use of altitude kits is acceptable provided that these kits are specified in the certification 

application and information is provided to the customer that identifies the altitude kit 

requirements.” 

EMA commented on §1054.501(b)(3) “How do I run a valid emission test?” EMA noted 

this section directs the manufacturer to perform testing under the ambient conditions specified in 

40 CFR Part 1065.520, however, the ambient pressure range specified in §1065.520 is a range 

from 80.0-103.325 kPa and the pressure range specified in §1054.115(c) is 94.0-103.325 kPa. 

Therefore, EMA commented that §1054.501(b)(3) should be revised to reflect the pressure range 

2-28 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

applicable to Small SI engines pursuant to §1054.115(c) and the reference to §1065.520 should 

be deleted. 

EMA commented on §1054.205(r) “What must I include in my application?” EMA 

commented that this section should be revised to clarify what information must be submitted in 

the certification application, and what information must be made available to consumers. Engine 

manufacturers routinely utilize engineering analysis to determine the altitude kit requirements 

which are correlated to engine function performance at different altitudes. However, the engine 

manufacturer does not have the ability to directly confirm emission compliance. EMA 

commented that this section should be revised so that it is clear that while the information 

provided to the engine owner must be accurate, it also should be easy to understand and not 

overly technical. Specifically, the information required to be provided to the engine owner 

should either enable the engine owner to determine whether or not an altitude kit is appropriate 

and necessary for their operating location or provide contact information for a resource that can 

assist with such determination. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

 The altitude-related requirements appropriately specify that emission standards apply for 

nonhandheld engines throughout the range of atmospheric pressures identified in §1065.520, 

specifically from 80 to 103.325 kPa. We are adopting special testing and compliance provisions 

related to altitude. We are requiring that nonhandheld engines meet emission standards without 

an altitude kit, but will allow, in certain cases, testing at barometric pressures below 94.0 kPa 

(which is roughly equivalent to an elevation of 2,000 feet above sea level) using an altitude kit. 

(An altitude kit may be as simple as a single replacement part for the carburetor that allows a 

greater volumetric flow of air into the carburetor to make the engine operate as it would at low 

altitudes.) Such kits were allowed under part 90 and we are keeping the provisions that already 

apply in part 90 related to descriptions of these altitude kits in the application for certification. 

This includes a description of how engines comply with emission standards at varying 

atmospheric pressures, a description of the altitude kits, and the associated part numbers. 

We agree that §1054.501 should reference the pressure-related provisions in §1054.115, but do 

not agree that the reference to §1065.520 should be deleted. 

OPEI’s comments generally supported the proposed standards and related requirements 

for complying with the regulations based on operation at high altitude. The requirement for 

nonhandheld engines to meet standards up to 94.0 kPa without an altitude kit and for 

manufacturers to specify the need for altitude kits to continue to comply with emission standards 

at lower pressures (or higher altitudes) fits with the recommendations spelled out in the 

comments. Also, EMA’s description of an approach to including altitude-related information in 

the owner’s manual is an excellent summary of what we would hope to see. The regulations are 

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Chapter 2: Small SI Engines 

somewhat less descriptive than EMA describes, but we would have no objection if manufacturers 

include the additional information suggested in the comment. 

We believe the proposed provisions requiring manufacturers to describe altitude-related 

information in the application for certification are clear. The regulations in §1054.205 specify 

simply that manufacturers must describe their plan for making information and parts available 

such that they would reasonably expect kits to be widely used in high-altitude areas. The 

example noted includes a very basic expectation that owners should have ready access to 

information describing when an altitude kit is needed and how to obtain this service. The 

detailed description included in EMA’s comments would be a satisfactory approach to meet 

these requirements. 

One thing engine manufacturers could consider adding in their communication to owners 

would be geographic-based information. For example, we identify in the regulation those 

counties with median altitudes greater than 4000 feet above sea level. Owner’s manuals or 

websites could include specific information to identify those areas as needing altitude kits for 

proper engine operation, if applicable. 

2.3 Averaging, banking, and trading 

2.3.1 Use of Phase 2 credits (and early Phase 3 credits) 

What Commenters Said: 

EMA noted that the implementation of Phase 3 exhaust emission standards clearly will 

play an important role in the continued improvement of the environment. Early introduction of 

clean technology that would further benefit the environment should be encouraged, and 

manufacturers should be afforded meaningful incentives for the early introduction of these 

cleaner Phase 3 products. It is imperative that EPA recognize that the ability of manufacturers to 

comply with the Phase 3 program is tied to their ability to use existing Phase 2 credits and the 

creation of transitional and enduring Phase 3 credits from the early introduction of Phase 3 

product. Engine manufacturers that have either provided a historical benefit or are eager to 

provide additional environmental benefit through either early compliance or the introduction of 

over achieving nonhandheld engines should be encouraged to do so. EMA recommended a 

number of changes to the NPRM in order to ensure the success of this important program. OPEI 

also recommended the same changes in their comments. 

First, EMA and OPEI commented that the requirement that both Phase 3 transition credits 

and Phase 3 enduring credits must be used prior to using Phase 2 credits should be revised. 

Engines that are introduced early and produce Phase 3 enduring credits are providing a 

substantial environmental benefit that should be encouraged. As proposed, there is no incentive 

for manufacturers to certify engines to FEL levels below the Phase 3 standard level because EPA 

would require the resulting enduring credits to be used prior to Phase 2 credits. Said another 

way, one of the costs to the manufacturer in investing in engines certified below the Phase 3 

level is the likely loss of Phase 2 credits. That is unfair, and makes no sense. As a practical 

matter, certifying below the Phase 3 level prior to expiration of Phase 2 credits would have no 

benefit to the manufacturer as currently proposed. Accordingly, in order to promote and 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

encourage the early introduction of Phase 3 and over-achieving nonhandheld products into the 

marketplace as soon as possible, engine manufacturers must be allowed to preserve the Phase 3 

enduring credits that they have the capability of generating (see §1054.740(c)). 

Second, EMA and OPEI commented that at the present time, the proposed AB&T 

program creates substantial concern and potential exposure to engine manufacturers because of 

their inability, despite their intentions, to be able to plan for such unforeseen factors as weather 

and customer demand. When that uncertainty is coupled with the proposed combined limitations 

on the use of Phase 2 and Phase 3 credits, manufacturers’ ability to ensure compliance is 

jeopardized. In order to prevent such unintended consequences, manufacturers should be 

allowed to utilize Phase 2 credit banks discounted by 20% per year or, in the alternative, if no 

Phase 2 credits exist, to carry a negative credit balance for up to two model years. The option for 

a manufacturer to maintain a negative credit balance would be at EPA’s discretion, based on the 

manufacturer’s ability to provide information demonstrating that any negative credit balances 

would be eliminated no later than the 2016 model year. In addition, EMA and OPEI envision 

that EPA would not allow a negative credit balance situation based on planned engine family 

FEL and volume projections, but only on unexpected volume adjustments occurring within an 

averaging set or the need to make an unanticipated upward adjustment to FEL due to an 

insufficient compliance margin, as determined from production line testing (see §1054.740). 

Finally, EMA and OPEI commented that engine manufacturers which have provided a 

benefit to the environment through the early introduction of Phase 3 credit generating 

nonhandheld engines should not be penalized regarding the use of those credits for the continued 

certification of their handheld engine families. Handheld engine families will continue to 

comply with the same exhaust emission standards under the proposed Phase 3 standards as the 

current Phase 2 engine families. A requirement for these carry-over handheld engine families to 

utilize Phase 3 nonhandheld generated credits is inappropriate and should not be included in the 

final rule. OPEI commented that these specific handheld families should be allowed to continue 

to use Phase 2 credits under the provisions EPA has outlined. 

CARB commented that in general it supports restrictions on credit generation and use to 

ensure that emissions benefits represented by the credits are accounted for properly. CARB 

commented that it would like to strongly discourage the concept of carrying an emission credit 

deficit. Manufacturers have sufficient time to plan for the change to new engines and they have 

the option to make the changes earlier than the deadline. If however, U.S. EPA chooses to allow 

the use of credit deficits, CARB would strongly encourage a stiff penalty to be added to the 

deficit as well as a set time limit as to the length of time the deficit may be carried. 

CARB also commented that EPA should allow only Phase 3 nonhandheld engine credits 

to be used under the handheld engine credit provisions after 2013. They believe that prohibiting 

the use of Phase 2 nonhandheld engine credits for demonstrating compliance with the Phase 3 

nonhandheld engine standards after 2013 is reasonable. 

2-31 
Chapter 2: Small SI Engines 

Letters: 

Commenter Document # 

EMA 0691 

OPEI 0675 

CARB 0682 

Our Response: 

EPA believes ABT programs are an important element in setting emission standards that 

are appropriate under Clean Air Act section 213(a) with regard to technological feasibility, lead 

time, and cost, given the variety of engines covered by the small SI standards. Depending on 

their design, ABT programs can create an incentive for the early introduction of new technology, 

allowing certain engine families to act as trailblazers for new technology. This can help provide 

valuable information to manufacturers on the technology before they apply the technology 

throughout their product line. Early introduction of such engines can also secure earlier emission 

benefits. Thus, EPA believes it is beneficial to design ABT programs to encourage use of the 

ABT program, especially provisions that encourage the early introduction of new technologies. 

EPA agrees that the proposed provisions requiring manufacturers to use their enduring 

Phase 3 credits before being allowed to use their Phase 2 credits allowance does not encourage 

the early introduction of Phase 3 engines during the Phase 2 timeframe. In order to encourage 

the introduction of Phase 3 compliant engines prior to implementation of the Phase 3 standards, 

EPA is eliminating the proposed provision that would require a manufacturer to use their 

enduring Phase 3 credits before using their Phase 2 credit allowance. Therefore, under the Phase 

3 ABT program, engine manufacturers will be required to use their Phase 3 transitional credits 

first. If their Phase 3 transitional credit pool is not sufficient, the manufacturer will be able to 

use their Phase 2 credit allowance second. Should that still not be sufficient, then the 

manufacturer will be allowed to use their Phase 3 enduring credits last of all to demonstrate 

compliance. 

With regard to the comments on credit deficits, EPA does not believe such provisions are 

necessary for the Phase 3 program. Given the amount of lead time before the new standards are 

scheduled to take effect and the provisions allowing use of limited Phase 2 credits, EPA believes 

manufacturers should be able to monitor their production levels and establish conservative FEL 

values (especially during the introduction of new engine families) to avoid situations where a 

deficit situation occurs. While EPA understands that manufacturers could find themselves in a 

situation where sales volume adjustments occur within an averaging set or an FEL needs to 

adjusted upward, EPA believes that such changes should be relatively small and within the 

manufacturers control to a great degree. Manufacturers participating in the ABT program would 

need to take these potential outcomes into consideration when making plans for complying with 

the Phase 3 standards through the use of the ABT program. 

Finally, in response to the comments on requiring manufacturers to use only Phase 3 

nonhandheld credits for handheld engines, EPA is not adopting such a requirement in the final 

rule. Under the Phase 3 program, in which we are not changing the Phase 2 exhaust standards 

for handheld engines, manufacturers of handheld engines will be allowed to use credits from 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Phase 2 handheld engines for their Phase 3 handheld engines without any restriction. Therefore, 

EPA believes it can allow manufacturers to use Phase 2 credits from nonhandheld engines to 

offset their high-emitting handheld engines under the constraints specified in the rule. (As noted 

in Section 2.3.2, EPA is adding an annual sales limit of 30,000 handheld engines for which a 

manufacturer can use nonhandheld engine credits.) 

2.3.2 Averaging sets and other restrictions 

What Commenters Said: 

EMA commented that the restrictions regarding cross-class trading of credits is 

appropriate during the introductory period when unrestricted trading could effect standard 

implementation, use of Phase 2 credits, and other factors. However, those restrictions should be 

removed beginning with the 2013 model year. Therefore, EPA should clarify that there are no 

restrictions for nonhandheld credit trading beginning with the 2013 model year (see 

§1054.740(d)). 

Honda commented that EPA should allow averaging, banking and trading (ABT) of 

credits across all engine categories, including handheld and nonhandheld engines. The proposed 

rule uses a stepped form of dividing engines and their respective emission levels into three 

categories, 0 to 80cc, 80 to 225cc, and above 225cc, and allows averaging and banking only 

within these separate categories. The inability to average and bank credits inherently applies 

more significant technical and economic challenges for engines of smaller displacements, within 

their class, to comply with the specific standard. The ability to supply engines in all 

displacement and horsepower categories is enhanced by the ability to “smooth” through 

averaging, exhaust standard steps in a way that resembles the feasible horsepower/displacement 

curve function. Honda understands that the proposed rule limits the use of existing Phase 2 

credits in order to “pull-ahead” the effective implementation of the regulatory standards. 

However, Honda believes that treatment of Phase 3 credits, including early Phase 3 credits, 

should be independent of the Phase 2 credits and commented that EPA should consider allowing 

averaging, banking and trading across Phase 3 categories, in the same manner allowed in Phase 

2. 

Honda commented that EPA should clarify in the final rule when and if an engine less 

than 80cc would be categorized as nonhandheld for ABT purposes if EPA does not allow Phase 

3 cross class averaging. Clarification or added guidance in the final rule would be useful where 

an engine less than 80cc is used in a nonhandheld product would qualify as nonhandheld for 

purposes of ABT, such as an engine used in a ground-supported mini-tiller. 

Letters: 

Commenter Document # 

EMA 0691 

Honda 0705 

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Chapter 2: Small SI Engines 

Our Response: 

With regard to the comment on cross-class trading of nonhandheld credits within the 

nonhandheld engine classes, EPA proposed to allow such trading starting in model year 2013. 

EPA has added language to specifically state that this is allowed in §1054.740 of the regulations. 

 EPA believes the proposed restrictions on credit exchanges between handheld and 

nonhandheld engines in the Phase 3 ABT program should be retained in the final rule (with the 

limited exception as noted below). While EPA is adopting more stringent exhaust standards for 

nonhandheld engines in this rule, EPA is not revising the Phase 2 exhaust standards for handheld 

engines. While most manufacturers tend to be in either the handheld engine market or the 

nonhandheld engine market, there are a few manufacturers that have a mix of engines falling into 

both categories. Under the Phase 2 program, where EPA allowed unrestricted averaging across 

both handheld and nonhandheld engine categories, some manufacturers were able to use credits 

from one category to delay introduction of cleaner technology engines in the other category. 

This gave these manufacturers a potential advantage in the market compared to other engine 

manufacturers that implemented the new technologies and did not have the ability to average 

with engines in the other category. EPA does not believe an ABT program should encourage 

such situations in the market. For this reason, EPA is retaining the averaging set restrictions for 

the Phase 3 rule which prevents averaging of emissions between handheld and nonhandheld 

engines (except as noted below). 

EPA is adopting the proposed provisions which allow manufacturers to use nonhandheld 

engine credits for handheld engines if the engine family was certified in 2008 based on carryover 

emissions data and the FEL does not increase above the level selected for the 2007 model year. 

Based on current certification data, only a small number of engine manufacturers would be 

impacted by these provisions and the number of handheld engines potentially affected is very 

small, with overall sales being less than 1 percent of handheld engine sales. However, because 

of concerns that manufacturers could increase their sales of such high FEL handheld engines, 

EPA is adopting one additional constraint. Under the final regulations, manufacturers may use 

nonhandheld credits for up to 30,000 handheld engines per year. EPA believes that the 

constraints being adopted regarding the use of nonhandheld engine credits for handheld engines 

should ensure that the sales of these handheld engines remain at their currently low levels. 

In regard to the comments on which engines certified to the handheld engine standards 

can generate nonhandheld engine credits, EPA proposed to allow manufacturers to generate 

nonhandheld ABT credits from engines below 80cc for those engines a manufacturer has 

determined are used in nonhandheld applications. EPA is retaining that provision in the final 

rule. Therefore, a manufacturer can generate nonhandheld engine credits from engines at or 

below 80cc that are subject to the handheld engine standards if the manufacturer determines they 

are used in nonhandheld applications (i.e., applications that do not meet the handheld definition 

in §1054.801 of the regulations). Because the engines are subject to the handheld engine 

standards, the credits would be generated against the applicable handheld engine standard. 

These nonhandheld credits could be used within the Class I and Class II engine classes to 

demonstrate compliance with the Phase 3 exhaust standards, subject to applicable restrictions. 

Given the restriction on mixing credits between handheld and nonhandheld engines, credits 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

generated by engines at or below 80cc used in handheld applications could only be used for 

handheld engines. 

2.3.3 FEL caps 

What Commenters Said: 

EMA supported the proposal that FEL caps should be established at the Phase 2 standard 

levels. EMA commented that the engine families previously considered Class I-B under the 

Phase 2 regulation and that are set to become Class I engines under the proposal must be allowed 

to utilize the prior Class I-B standard level at the FEL cap as those engines were not subject to 

the Phase 2 Class I standard levels. 

Letters: 

Commenter Document # 

EMA 0691 

Our Response: 

EPA agrees with the comment that FEL caps should be established at the Phase 2 

standard levels. The final rule includes such a requirement in §1054.103(b) by stating that a 

manufacturer may not specify a family emission limit that exceeds the applicable Phase 2 

standards as specified in 40 CFR 90.103 and summarized in Appendix I of Part 1054. 

2.3.4 Credit life 

What Commenters Said: 

Both EMA and OPEI commented that they oppose the proposition that any engineexhaust or evaporative credits generated by a manufacturer should have an arbitrary life period. 

Emission credits are either generated through the voluntary early implementation of new 

emission control technology or introduction of products that are cleaner than required by the 

applicable emission standard. Such credits are generated at a cost to the manufacturer, and are 

granted in exchange for the manufacturer’s independent decision to produce products that 

provide additional benefits to the environment. These credits are important assets that should not 

be arbitrarily lost due to time or actions not under the manufacturer’s control. 

CARB commented that it strongly urges EPA to limit the credit life of exhaust credits 

earned to five years. They commented that emission credits should not outlast the equipment 

which allowed the manufacturer to attain the credits. CARB also commented that a five year 

limit on the credit lifetime would also be consistent with the proposed useful life requirements 

under which the engine manufacturers would be required to warrant the engine for five years. 

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Chapter 2: Small SI Engines 

Briggs & Stratton commented that it opposes any limitation on the life of ABT credits. 

Engine manufacturers should not be punished for not using the credits in an arbitrary time frame. 

Briggs and Stratton also commented that the proposed ABT provisions almost completely 

eliminate the Phase 2 emission credits that have been generated by small engine manufacturers. 

Engine manufacturers in good faith generated Phase 2 credits under the current regulations. The 

proposal by EPA is a significant loss to the engine manufacturers. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

CARB 0682 

Briggs and Stratton 0657 

Our Response: 

We are retaining the unlimited lifetime for Phase 3 ABT credits, as proposed. While 

EPA is retaining the unlimited lifetime, EPA notes that manufacturers should not assume that 

Phase 3 credits will be available without any restrictions on their use if, and when, EPA should 

consider a new round of emission standards in the future. In setting new emission standards, 

section 213(a) requires of the CAA requires EPA to set emission standards that achieve the 

greatest degree of emission reduction achievable through the application of technology which 

EPA determines will be available for the engines or vehicles to which such standards apply, 

giving appropriate consideration to the cost of applying such technology within the period of 

time available to manufacturers and to noise, energy, and safety factors associated with the 

application of such technology. If manufacturers have a large pool of ABT credits available to 

them, EPA must consider ways to ensure that those credits do not result in an unnecessary delay 

of the standards. This can be done in a variety of ways, and has been done in the Phase 3 final 

rule by allowing only limited numbers of Phase 2 credits to be used for a limited period of time 

during the transition to the new Phase 3 standards. 

EPA does not believe a limit on the life of Phase 3 credits is needed at this time for the 

ABT program adopted with today’s program. Phase 3 credits will be generated at a cost to 

manufacturers and thus they will have a value to the manufacturers. EPA believes provisions 

which limit a manufacturer’s ability to use credits during the Phase 3 timeframe, such as a limit 

on credit life, will reduce the incentive for manufacturers to invest in the development and 

introduction of new technology. However, as mentioned above, manufacturers should not 

assume that an unlimited life for Phase 3 credits means those credits will be available without 

any restrictions on their use if, and when, EPA should consider a new round of emission 

standards in the future. As part of any future rulemaking, EPA would expect to consider ways to 

ensure that the Phase3 credits existing at that time would not result in an unnecessary delay of 

any future standards. 

With regard to the comment on the loss of Phase 2 credits, EPA does not believe 

manufacturers have a right to use those credits indefinitely. In fact, EPA would like to point out 

that such a scenario was clearly a possibility and was noted in the Summary and Analysis of 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Comments document for the Phase 2 nonhandheld rule. (“Summary and Analysis of Comments, 

Phase 2 Emission Standards for New Nonroad Spark-Ignition Nonhandheld Engines At or Below 

19 kW,” March 3, 1999, docket item EPA-HQ-OAR-2004-0008-____.) In response to 

comments on the unlimited lifetime of Phase 2 ABT credits, EPA stated that while it was 

adopting an unlimited credit lifetime for Phase 2 ABT credits at the time, EPA did not wish to 

limit its ability to address possible unforeseen conditions that arise as a result of the program in 

future rulemakings. EPA further stated that it would be able to reconsider the appropriate life of 

Phase 2 ABT credits in connection with any post-Phase 2 rulemaking. 

2.3.5 Other ABT Issues 

What Commenters Said: 

EMA submitted a number of comments on specific regulatory sections. EMA 

commented on §1054.105(b) “What exhaust emissions standards must my non-handheld engines 

meet?” EMA noted that while the proposed AB&T program is restricted to HC+NOx emissions, 

the NPRM does not expressly state that CO emission standards cannot use AB&T (as previously 

included in Part 90.201). Because the proposal includes a compliance requirement with the 

significantly lower CO standard for marine generator engines, EMA commented that the final 

rule should clarify that AB&T is not applicable to CO emissions. 

EMA commented on §1054.715(b) “How do I bank emission credits?” They commented 

that reserve credits cannot be traded. Therefore, EMA recommends that the reference to 

“trading” should be deleted from this section. (Also included in Section 4.4.5) 

EMA commented on §1054.725(b)(2) “What must I include in my application for 

certification?” They commented that engine families that generate or use credits at the time of 

certification should not be required to designate their credit destination or origin within the 

averaging set. (Also included in Section 4.4.5) 

EMA commented on §1054.730(f)(3) “What ABT reports must I send to EPA?” EMA 

commented that if an error mistakenly increases a manufacturer’s balance of emission credits, 

correction of the errors and recalculation of the balance of emission credits should be undertaken 

at the manufacturer’s discretion. They manufacturer should not be required to correct the errors 

and recalculate the balance of emission credits as currently proposed. (Also included in Section 

4.4.5) 

EMA commented on §1054.735(d) “What records must I keep?” EMA commented that 

the requirement to keep additional records for each engine or piece of equipment including the 

engine identification number, build date and assembly plant is excessive and beyond the current 

requirements of 40 CFR Part 90.209. They commented that these additional record keeping 

requirements either should be deleted or replaced with engine manufacturer records associated 

with products produced. (Also included in Section 4.4.5) 

EMA commented on §1054.735(e) “What records must I keep?” EMA commented that 

this section appears to be arbitrary and capricious. EPA should not be allowed to require 

manufacturers to keep additional unspecified records or demand additional information not 

required by the rule without a proper purpose or for cause. EPA should be required to support 

any imposition of additional record keeping requirements or demand for additional information 

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Chapter 2: Small SI Engines 

with specific and appropriate reasons. Further, such decisions should not be made unilaterally by 

EPA, and the manufacturer must have the ability to question any such request and, if necessary, 

request a formal hearing process. (Also included in Section 4.4.5) 

EMA commented on §1054.625(j)(2) “What requirements apply under the Transition 

Program for Equipment Manufacturers?” EMA commented that the requirement to multiply 

credits generated by an engine family by 0.9 must be limited to engine families that are actually 

utilized by equipment manufacturers under the §1054.625 flexibility provisions. In addition, 

EMA commented that engine manufacturers should have the option to track the correct number 

of engines that utilize the §1054.625 flexibility provisions and adjust ABT credit calculations 

based on the actual number of engines. 

OPEI commented that the "flex" provisions will not be implemented if excessive 

regulatory burdens discourage engine manufacturers from participating in that program. OPEI 

believes an unintended possible outcome of the proposed ABT credit adjustment program is the 

creation of a disincentive for engine manufacturers to participate in the flexibility program. Such 

a credit adjustment requirement would be unfair (in terms of lost, banked, credits) and would 

also be overly burdensome to administer. To OPEI’s knowledge, such ABT credit adjustments 

are not part of EPA's other similar equipment flexibility programs. If such an adjustment 

program is required, OPEI recommended that the credit adjustment provisions for Delegated 

Assembly be clearly defined as applicable only to those discrete engine families that utilize the 

Delegated Assembly provisions and are also participating in the flexibility program pursuant to 

Section 1054.625(c)(2). There are many circumstances where no Delegated Assembly engines 

will be utilized for equipment manufacturer flexibility programs and discounting of credits 

should not occur under any scenario. If a credit adjustment program is required, engine 

manufacturers must be given the option to participate in the flexibility program pursuant to 

§1054.625(c)(2). 

Letters: 

Commenter Document # 

EMA 0691 

OPEI 0675 

Our Response: 

With regard to the comment on CO, the ABT program for small SI engines does not 

cover CO emissions. EPA agrees that language stating that CO is not part of the ABT program 

should be included in the Part 1054 regulations. EPA has revised §1054.103 and §1054.105 to 

include such language. 

EPA disagrees with the comment on §1054.715(b) suggesting that reserved credits cannot 

be traded. The existing Phase 2 ABT regulations in 90.206(b), allow manufacturers to trade 

current model year credits. Current model year credits are “reserved” credits by definition, 

because manufacturers do not submit their end-of-year and final reports until after the model 

year is finished. Therefore, EPA believes it is appropriate to include similar language in the 

Phase 3 ABT regulations stating that reserved credits can be traded. Therefore, §1054.720 of the 

regulations states in paragraph (b) that a manufacturer may trade reserved emission credits. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Also, it should be noted that the language of §1054.715, paragraph (b) which was noted by the 

commenter in their comments has been changed to fix an inconsistency in the regulations. The 

proposed language stated that a manufacturer’s credit projections submitted at the time of 

certification were considered “reserved credits.” This is not the case as “reserved credits” are 

defined in §1054.701 as credits that have been generated, but not yet verified by EPA. In order 

to generate credits, the manufacturer must actually build engines, not just project that they will 

build engines. However, the revised language of 1054.715(b) also allows reserved credits to be 

traded. 

EPA agrees with the comment on §1054.725(b)(2) suggesting that manufacturers not 

have to designate the credit destination or origin for each of its engine families and has removed 

that requirement from the regulations. However, for engine families that are projecting to use 

emission credits (i.e., the engine family has a negative credit balance), EPA believes that a 

manufacturer should provide information on where they will obtain credits for that engine 

family. Therefore, at the time of applying for certification, a manufacturer will be required to 

submit certain information to EPA. For the Phase 3 ABT program, the regulations require 

manufacturers to provide the FEL for the engine family, and detailed credit calculations for the 

engine family, as well as where they will obtain credits for their credit using families (i.e., from 

banked credits, from averaging with other current engine families certified with FELs below the 

standard, or from trading with other engine manufacturers). EPA does not believe it is necessary 

to require manufacturers to provide any further information, including a detailed accounting of 

where they plan to use their credits or if the credits they plan to use are actual or reserved, as 

proposed. 

EPA disagrees with the comment on §1054.730(f)(3) suggesting that a manufacturer be 

allowed to fix errors in the credit reports at its discretion. If errors are discovered at any time 

showing that a manufacturer has earned too many credits, then EPA believes a manufacturer 

should be required to correct the error. The ABT program is meant to ensure that the average 

emission level of all participating engines meet the applicable standard. An error in the ABT 

reporting that results in more credits being generated than should be generated could result in the 

average emission level being above the emission standard even though the original credit 

calculations did not show such a result. Requiring manufacturers to fix such errors would allow 

EPA to then address any resulting noncompliance. 

In response to the comment on §1054.735(d) that the information a manufacturer is 

required to keep for ABT is excessive, EPA is making some changes to the regulations. EPA 

believes the changes will still allow us to have access to important information if needed, 

especially if a noncompliance situation arises. Under §1054.730 of the final regulations, 

paragraph (b) requires manufacturers to report a variety of information for engines participating 

in the ABT program including family designation, FEL, useful life, and the production volumes 

for each participating family. Under §1054.735, manufacturers will be required to keep a copy 

of the reports submitted to EPA under §1054.730 along with a record of the identification 

number for each engine produced. If there are multiple FELs in an engine family, the 

manufacturer will need to keep records of the identification number associated with each FEL. 

Manufacturers may identify these numbers as a range. Manufacturers will not be required to list 

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Chapter 2: Small SI Engines 

the build date for each engine produced, nor will they be required to keep information on the 

assembly plant as originally proposed. 

With regard to the comment on §1054.735(e) on the provisions requiring manufacturers 

to keep or allowing EPA to request additional unspecified records or relevant information, EPA 

believes such a requirement is allowable and necessary. Section 208 of the Clean Air Act (which 

applies to nonroad engines under section 213(d) of the Clean Air Act) describes the information 

collection requirements for manufacturers. Under those requirements, manufacturers must 

provide information EPA may reasonably require to determine whether manufacturers have 

acted in compliance with regulations. While EPA has listed the specific information a 

manufacturer must keep for the Phase 3 ABT program in §1054.735, it is possible in the future 

that we may identify other information that would be needed to deal with a specific situation. 

The provisions in paragraph (e) of §1054.735 would allow us to request such information. Of 

course, EPA would only request such additional information if it were in accordance with the 

law, such as provided for in section 208 of Clean Air Act. In addition, EPA would only expect 

manufacturers to keep and provide such information after we have put such a request into effect, 

either through a rulemaking change or guidance to manufacturers. In response to the comment, 

EPA has revised the language of §1054.735 paragraph (e) to reflect that EPA will request 

information if it is in accordance with the law. Finally, in response to the comment on 

requesting a hearing if a manufacturer believes EPA’s request is inappropriate, the proposed 

regulations allow a manufacturer to request a hearing from EPA under §1054.745, paragraphs (c) 

and (d). EPA has retained those requirements in the final regulations. 

In regard to the comments on §1054.625(j)(2) on adjusting ABT credits for creditgenerating engine families that are available under the delegated-assembly provisions, EPA 

continues to believe it is appropriate to adjust such credits. Rather than imposing a disincentive 

from participating in the transition program for equipment manufacturers (TPEM) program, the 

credit adjustment merely accounts for the fact that equipment manufacturers may in many cases 

legally install a non-catalyzed muffler on an engine that is part of a family whose certification 

depends on the use of a catalyst. It is true the EPA has not adopted this adjustment for other 

engine categories, but this is because most other engine categories do not have a TPEM program 

and none of them allow engine manufacturers to produce these engines without specifically 

identifying them as exempt TPEM engines. EPA wishes to clarify that the adjustment applies 

only to engine families that are available under the delegated assembly provision and are also 

participating in the TPEM program. As noted in the proposal, the proposed credit adjustment 

factor of 0.9 is intended to represent the maximum estimated usage of the TPEM program across 

the broad range of equipment manufacturers. However, EPA understands engine manufacturers’ 

concerns that the adjustment may not reflect the actual number of engines that are downgraded 

for use in the TPEM program. Therefore, for the final rule, EPA is retaining the 0.9 adjustment 

factor. In addition, EPA is including an option that will allow engine manufacturers to track the 

final configuration of the engines to determine the actual number of engines that were 

downgraded for the TPEM program. A manufacturer would need to track sales for all of the 

equipment manufacturers purchasing the given engine family. The engine manufacturer could 

use the resulting number of engines that were not downgraded in its calculation of ABT credits 

for that specific engine family. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

2.4 Certification 

2.4.1 Changing the FEL mid-year (and printing FELs on labels) 

What Commenters Said: 

OPEI and EMA disagreed with EPA’s negative assessment of FEL changes made during 

the model year. Currently, engine manufacturers may set their initial FEL levels to a level that 

they are confident will pass production audits and will not result in compliance concerns 

(provided compliance with the standard requirements is achieved). If, based on the actual 

production audit results and subsequent Cum-Sum analysis, the manufacturer determines that the 

FEL could have been lower from the beginning of the model year (or implementation of a 

running change), OPEI commented that the manufacturer should be allowed to claim credit for 

the environmental benefit actually provided. The ability to correct the FEL level also provides 

the manufacturer with a limited ability to recoup credits under the EPA program that are 

otherwise available to manufacturers under CARB’s PLT credit program. 

OPEI agreed that lowering the FEL should have a limit. A manufacturer that has already 

submitted production line test data for a family should not be allowed to retroactively (even at a 

point in the 4th quarter that would apply back to the first quarter) lower the FEL later in the 

model year to a level that would result in a CUM-SUM failure from earlier tests in the model 

year. This in effect sets a cap on the FEL change. 

OPEI and EMA commented that the proposed rule’s requirement to include the FEL 

numerical reference on the engine emission label would prevent the manufacturer from being 

able to accurately represent (in the CARB PLT credit case) or retroactively change FEL levels. 

They commented that the final regulation should provide the engine manufacturer the ability to 

make retroactive FEL adjustments. Also, in order to allow such adjustments, OPEI and EMA 

believe it is essential that EPA drop the proposed FEL labeling requirement. 

OPEI noted that CARB does not require either exhaust or evaporative family emission 

levels (FELs) to be placed on the emission label. EPA’s proposal to add individual evaporative 

and exhaust family emission levels (FELs) on the label would be inconsistent with CARB, would 

further confuse consumers, and would be totally impractical for manufacturers. For example, 

consumers could end up unintentionally buying a product with more horsepower that emitted 

greater mass emissions because the consumer did not realize the FELs are normalized to a single 

kilowatt. Such FEL labeling will also facilitate additional local purchase restrictions and use 

bans in direct violation of Section 209(e) of the Clean Air Act and the related legal precedent on 

federal pre-emption (as discussed below in Section XIV). For all these reasons, OPEI 

commented that EPA should drop completely its proposed exhaust and evaporative FEL labeling 

requirement. (Comment also included in 4.6.1 and 4.6.3) 

EMA commented on §1054.701(e) “General provisions.” EMA believes the requirement 

that an FEL can only be adjusted applicable to future production is not appropriate and should be 

deleted. For example, if a manufacturer determines, based on PLT test results, that the margin 

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Chapter 2: Small SI Engines 

for compliance is inadequate and that credits exist either from the current model year or prior 

model year banked credits, it should be allowed to increase the FEL for the entire model year. 

With regard to FEL changes, CARB commented that it agrees with EPA that any 

revisions to the FEL should only apply to engines produced after the FEL change. They agree 

that it would be difficult to test the engines before the FEL change because verifying the engine 

emissions from previously produced engines would be difficult. 

Briggs and Stratton noted that EPA asked for comments on including the FEL on the 

emission labels. Briggs & Stratton disagrees with this proposal. The addition of the FEL on 

emission labels provides no benefit to consumers, EPA, or the environment. However, this 

proposal does impose a significant burden on both the engine manufacturer and the OEM. They 

noted that supplemental labels are required for many applications where the emission label is 

obscured in the final product. If the FEL must be printed on the emissions label a new emission 

label is required whenever the FEL is changed. This creates more costs and labels to manage for 

the engine manufacturer and the equipment manufacturer with no commensurate benefit to the 

environment. Briggs and Stratton commented that EPA should delete the requirement for the 

FEL to be printed on the label. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

Briggs and Stratton 0657 

EMA 0691 

Our Response: 

We maintain two principles that contradict the manufacturers’ comments regarding FEL 

changes and printing FELs on emission labels. First, we believe that each engine a manufacturer 

produces should be associated with a family emission limit at the point of production. This is 

important for ensuring proper accountability and enforceability. If manufacturers are able to 

assign FELs after production with the only restriction being related to compliance with statistical 

calculations for production-line testing, there is a great concern that it would be very difficult to 

confirm that FELs were assigned appropriately. Similarly, if accountants change FELs 

retroactively, it would be very difficult to test engines after they have been placed into service 

and establish whether it meets emission standards or not. There would seem to be no clear way 

of knowing which FEL applied to which engine. 

Second, the intent of production-line testing and the underlying statistical calculations 

depend on the engine having a specific and permanent applicable standard (with or without an 

FEL). The statistical calculations are based on a given number of engines passing or failing the 

applicable emission standard out of a bigger population representing the complete emission 

family. Repeating the CumSum calculations after the end of the year has the effect of simulating 

the engine family as if the tested engines were the complete population. Aside from the bad 

math, we believe manufacturers should set their FELs with the understanding that they are liable 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

for the test results as they are generated. Waiting until the end of the year to set the real and final 

FEL sets up an incentive for the manufacturer to use a high FEL through the year, then simply 

reduce the FEL at the end of the year as much as the statistics allow. This puts the manufacturer 

in a position of having almost no liability from production-line testing. In contrast, we believe 

manufacturers should set the FEL for a family only as low as they can based on the 

understanding that tested emissions must comply with the named FEL. If manufacturers learn 

early in the model year that their FEL is higher than it needs to be, they may decrease the FEL as 

much as can be justified based on prior testing and use that lower FEL for most of the model 

year to generate larger quantities of credits (or use smaller quantities). 

We proposed to require manufacturers to print FELs on emission labels. This is common 

across our programs and is intended to help us clearly establish the applicable emission standard 

for each engine. In discussions after the close of the comment period, manufacturers agreed with 

us that it would be as effective for the manufacturers instead to keep records to correlate engine 

build dates with changing FELs. For example, if a manufacturer would change the FEL for an 

engine family for production engines starting June 14 of a given year, it would keep a record of 

engine identification numbers that would allow them to identify the applicable standard for each 

engine. If manufacturers choose to identify their build dates by month and year (without the 

specific date), the presumed build dates would default to least favorable dates for the 

manufacturer. In the case of an FEL increase on June 14, this means the manufacturer would 

apply the new FEL starting with engines produced on June 1; conversely, a decreased FEL 

would apply starting with engines produced on June 30. This flexible approach would allow the 

manufacturer to forego some emission credits for the advantage of being less careful with 

tracking engine serial numbers with build dates. This approach for assigning dates for 

calculating emission credits may be slightly different than the timing associated with the revised 

certificate that we would issue for the engine family; however, we believe this should not be a 

problem. 

Along with the requirement to keep records of engine build dates with FEL changes, we 

are adopting a requirement for the manufacturer to report this information in the ABT reports 

submitted after the end of the model. These engine identification numbers may be submitted as a 

range of values to streamline the report as much as possible. 

2.4.2 Useful life implementation (and labeling) 

What Commenters Said: 

CARB commented that it agrees with U.S. EPA that a numerical value is the best way to 

describe the useful life of equipment. If other terminology is used, CARB suggests that both the 

descriptive terminology and the numerical value should be used. If only one can be used, then 

CARB suggests that the numerical value representing the useful life be retained. 

NESCAUM commented that it supports EPA’s proposal to require engines and 

equipment be labeled in a manner that will help the user better understand the intended useful 

life of the equipment. They believe using descriptors such as Residential, Premium Residential, 

2-43 
Chapter 2: Small SI Engines 

Commercial, and Heavy Commercial will be helpful in this regard, provided that there is a 

means to match the descriptor against a specified useful life period in terms of operating hours or 

years. 

OPEI commented that it is concerned that a consumer may become confused if only the 

hours are listed on the label. A 125-hr handheld product is considered “Premium Residential” 

according to EPA while a 125-hour Class I engine would be classified as “Residential”. To 

avoid this confusion OPEI requested the EPA allow for the use of hours, or the use of descriptive 

terms (Light Use, Medium Use, Heavy Use), or the use of both hours and descriptive terms on 

the label. OPEI agrees that Class I and Class II engines and their applications require different 

terms of usage. 

OPEI requested that a handheld product manufacturer would have the choice of using any 

of these three options to describe the Useful Life period. OPEI supports the use of the terms 

“Light Use”, “Medium Use”, and “Heavy Use” to characterize the three useful life categories 

applicable to handheld engines instead of the terms EPA has proposed. OPEI believes their 

proposed terms best meet EPA’s objective of accurately describing the intended use to the 

purchaser. It is possible that a commercial operator may buy a product with a lower useful life 

but the usage pattern of the product would fit the description of the useful life. The integrated 

nature of handheld products allows a more transparent understanding of the durability of the 

product through marketing and other means. 

OPEI noted that §1054.107(a)(4) deals with keeping information available to support 

Useful life selection. In addition, OPEI noted that page 88 of the Preamble states EPA intention 

to review Useful-life selection if not highest value. By default, if a manufacturer certifies to 

highest value, they are showing through cert testing that the engine meets the useful life period. 

OPEI commented that EPA should add language in §1054.107(a)(4) to confirm that EPA will 

approve the manufacturer’s useful life selection without further demonstration if the 

manufacturer selects the highest available useful life value and submits data showing that the 

engine lasted that long as part of the durability demonstration for certification. 

OPEI notes that §1054.107(a)(4)(i) life time surveys are a point of interest for most 

manufacturers; “If a manufacturer has data to support an engine/product has the majority of its 

family sales sold to a market (for example homeowner use) then the manufacturer may certify 

the product/engine to an appropriate useful life provided the data supports that majority of the 

product built and sold does not exceed the actual usage time.” OPEI commented that if a 

manufacturer has a family where 70% of sales can be proven to be to homeowners and you can 

prove that a large majority, for example greater than 75%, of those homeowners will never use 

the product more than 125 hours before scrapping it, the manufacturer should be allowed to 

certify it to 125 hours even if the engine can be demonstrated to last longer. 

EMA commented that it is critical that EPA recognize an engine’s useful life period, as 

determined by the engine manufacturer prior to certification and production, does not dictate the 

ultimate equipment manufacturer or ultimate consumer’s usage of the engine. There are a 

significant number of engines produced in this product category that will never be used for the 

prescribed emission durability period regardless of the years of use. There are also a very small 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

number of engines in this category that will accumulate hours at a much faster rate, and 

depending on the equipment design, may be replaced prior to the expiration of the emission 

durability period. In many cases this usage disparity exists within a single given engine family. 

EMA commented that EPA’s criteria for acceptance of useful life must be expressly 

established and documented in order to assure consistent treatment and a level playing field. A 

manufacturer’s decision to select the longest useful life period should require the same 

justification as other useful life period selection. The criteria used to approve emission durability 

periods must clearly be identified in the regulatory text or preamble language. Manufacturers 

must receive guidance from EPA regarding what types of records EPA expects to review in the 

event it asks a manufacturer to substantiate its selection of an engine’s durability period. In 

addition, EMA commented that the final rule should expressly acknowledge that industry survey 

information regarding product categories usage patterns, such as previous OPEI surveys, is 

acceptable documentation of a manufacturer’s useful life selection. 

EMA commented on the proposed statement required by §1054.135(c)(4) “How must I 

label and identify the engines I produce?” EMA objects to the statement and commented that the 

manufacturer should have the option to include language associated with the emission durability 

period in the compliance statement. Accordingly, there should be a reference to 

§1054.135(c)(12) in this section. 

Letters: 

Commenter Document # 

OPEI 0675 

NESCAUM 0641 

CARB 0682 

EMA 0691 

Our Response: 

This is the only program in which we allow manufacturers the discretion to select an 

engine family’s useful life. We believe this is a necessary accommodation for the reality that 

similar engines can be designed and used for widely varying purposes, users, and applications. 

Making this selection is nevertheless fundamental to defining the stringency of the standards that 

apply to the engine family so we strongly believe we should set up clear, objective, and practical 

guidelines for choosing an appropriate useful life in each case. We should also have a role of 

monitoring compliance with these guidelines and intervening in cases where a manufacturer is 

misusing the available discretion to assign an inappropriately short useful life. We have 

observed several cases under the Phase 2 program where manufacturers select the shortest 

available useful life for an engine family where the engines are clearly designed and marketed as 

long-life products for commercial applications. In contrast, some manufacturers have chosen a 

mix of useful-life values that seems to appropriately match the varying design parameters and 

intended usage patterns. Our intent is to create a program in which we can ensure that all 

companies are together taking this approach of responsibly pairing useful life with the expected 

in-use operating life. 

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Chapter 2: Small SI Engines 

As described in the proposed rule, we believe emission labels need to clearly state the 

manufacturer’s selected value for the useful-life period, in hours. Under the regulation, 

manufacturers are directed to select the useful life that most closely correlates with the 

equipment’s expected lifetime of service. We believe this decision is important not only for 

emission controls, certification, and compliance but also for consumers. If a manufacturer puts 

in additional engineering and product features such that an engine can operate twice as long as a 

competitor’s engine while meeting emission standards throughout the longer useful-life period, 

that should be clearly identifiable to the consumer as a superior product. The current approach 

of identifying the useful life with a single-letter code does not communicate useful-life 

information clearly enough. Similarly, we believe that descriptive terms may be helpful in 

communicating useful-life information, but they cannot replace the objective value of identifying 

useful life with a universal and clearly understood metric. Including the engine operating hours 

to identify the useful life is the best way to achieve this. 

We believe it may also be helpful to add descriptive terms to further characterize an 

engine’s useful life. We will therefore allow manufacturers the option of using prescribed 

wording in addition to identifying the hour value for the useful life. We are adopting the terms 

described in the proposal for nonhandheld engines. We believe these terms are well matched to 

the range of uses for nonhandheld applications. We have no objection to the wording suggested 

for handheld engines. Using different terms may be helpful to avoid any confusion that may 

result from attaching the same descriptive terms to different useful-life values for handheld and 

nonhandheld engines. 

Application Useful Life (hours) Descriptive Terms 

50 Light use 

Handheld 125 Medium use 

300 Heavy use 

125 Residential 

Nonhandheld Class I 

250 Extended life residential 

(or general purpose) 

500 Commercial 

>500 Heavy commercial 

250 Residential 

Nonhandheld Class II 

500 Extended life residential 

(or general purpose) 

1000 Commercial 

>1000 Heavy commercial 

We agree with EMA that the criteria for establishing an engine family’s useful life should 

be clearly defined and evenly applied for certifying engines. We also agree that the selected 

value should not prevent equipment manufacturers from installing engines according to the their 

own judgments about which engine is best suited to their particular equipment models, and that 

owners should not be restricted in how (or how long) they use their engines or equipment. 

Information about how equipment manufacturers and owners are selecting, installing, and using 

2-46 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

engines may factor into the engine manufacturer’s decision regarding useful life, but once the 

engine family has a useful life, that value should not be limiting for equipment manufacturers or 

owners. 

The regulation text we proposed and are adopting in §1054.107 is changed very little 

from the current regulation in §90.105, which was adopted in 1999. As described above, many 

engine manufacturers have been taking a responsible approach in exercising their discretion to 

select useful-life values. We therefore believe that the proposed regulation, with a few minor 

modifications, suitably defines the process for defining the terms and criteria for selecting useful 

life. Fundamentally, the regulations require that manufacturers select the useful life value that 

best represents the expected median in-use life of the equipment in which the engine will be 

installed, including specification of a variety of information types for supporting the selection. 

We do not expect a dramatic change from current practice for those manufacturers that are 

already making a good-faith effort to make proper selections. Making the effort to document the 

basis for making these selections, which is already required under §90.105, and subjecting those 

decisions to EPA review will ensure that all manufacturers receive equal treatment under the 

regulations. This will be a substantial improvement over the Phase 2 program where 

manufacturers may find themselves at a competitive disadvantage by making responsible usefullife selections. 

While we believe the regulation is sufficiently clear in establishing the meaning of useful 

life and the process for making selections, we agree that further guidance will be helpful in 

taking the next step of making concrete decisions about which useful-life value most 

appropriately represents a particular engine family. This will give manufacturers assurance that 

useful-life selections will be made consistently across the industry, and will further help to 

ensure an orderly process for certification. 

We agree with OPEI that engine manufacturers selecting the longest nominal value 

would not need to do any more than submit certification data showing that an engine 

representing the engine family operated long enough to appropriately establish deterioration 

factors. If there were any reason for a manufacturer to select a useful life that is too long (such 

as artificially generating credits from an engine family with a low family emission limit), we 

would see that under the Phase 2 program where we have not asked manufacturers to justify their 

selections. We have observed no such abuse under the Phase 2 program, so we have no reason to 

believe that would occur in the future. With no potential to require manufacturers to select a 

longer useful life, we therefore believe it is unnecessary for manufacturers to provide any 

additional information to justify their selection of the longest available nominal value for the 

useful life. 

The regulation allows manufacturers to rely on product-specific surveys to establish the 

median life span of equipment in the field. It would not be appropriate to rely on broader 

surveys that characterize usage patterns or lifetimes for aggregated products, since that would 

provide no information that would demonstrate any greater reliability or durability that may 

apply for any particular engine family. It would not be appropriate to use industry averages to 

justify lifetime estimates for individual models. On the other hand, if a manufacturer has two 

engines with similar designs and technical features (such as one- and two-cylinder versions of an 

2-47 
Chapter 2: Small SI Engines 

otherwise common engine), it may be possible to draw conclusions about useful life for both 

engine families from a single survey. We would expect such a survey to avoid sampling criteria 

or other statistical methods that would distort the results. 

Conducting a survey is most straightforward when an engine is installed in a small 

number of equipment models and is generally placed into service such that usage characteristics 

are relatively uniform. This situation is common for the highest-volume handheld and 

nonhandheld products. A more challenging situation occurs when engines are installed in a wide 

range of equipment models and users have widely varying usage patterns. In these cases, we 

would expect manufacturers to make sound judgments in selecting dominant equipment models, 

applications, and usage characteristics to determine a useful-life value that best represents the 

median lifetime of the range of equipment in which the engines are installed. This may reflect a 

combination of commercial and residential use. Surveys could also take into account the 

possibility that individual owners may choose to retire a piece of equipment before it has reached 

the point of no longer being able to run (for example, by upgrading to a new model with 

additional features). The manufacturers are generally selecting the useful life from three nominal 

values, so the goal of any survey is limited to establishing the proper useful life only to that level 

of precision. We would not expect manufacturers to estimate the median lifetime of in-use 

equipment to the nearest hour to be able to select the useful life for an engine family for 

certification. 

In discussions following the close of the comment period, some manufacturers expressed 

concern that gathering information from the field to determine appropriate useful-life values for 

each engine family would be very costly and time-consuming. We will be learning together how 

detailed that information needs to be and to what extent the information can be shared across 

engine families. In the meantime, we would also encourage nonhandheld engine manufacturers 

to consider the alternative specified in the regulations allowing for useful-life determinations 

based on engineering evaluation. Toward that end, we have made an effort to correlate engine 

design features with useful-life values. We considered including these design features directly in 

the regulation, but chose to continue with the broader approach consistent with the current 

specifications in §90.105. To the extent that nonhandheld engine manufacturers are unable to 

easily gather information to establish median equipment lifetimes corresponding to their engine 

families, we would consider the engine design features in the following table to be an adequate 

basis for establishing the useful life for a given engine family. Manufacturers using the values as 

indicated in the table would need to provide no additional information. We are aware that 

pressurized lubrication and cast-iron cylinder liners can take different forms (or have different 

degrees of quality and durability), but we would consider any form of these technologies to 

correspond to the indicated useful-life values, since they are clearly intended (and expected) to 

provide substantial improvements in engine operating life. We may revise this approach to 

correlating engine design features to useful-life values based on testing or other information that 

allows us to more carefully establish median lifetimes for specific designs. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

 Design Features for Nonhandheld Engines and Corresponding Useful Life Values 

Design Features Useful Life 

Pressurized lubrication and more than one cylinder 1000 hours 

Pressurized lubrication or more than one cylinder 500 hours 

Engine displacement at or above 225 cc or a cylinder liner 250 hours 

Any other engine design 125 hours 

Finally, manufacturers may choose to do testing instead of relying on survey information. 

In this case, we would envision the manufacturer assembling five pieces of equipment that best 

represent the engine family. Testing could also be done with engines on a dynamometer. These 

engines could be exercised until the point of failure under normal operating conditions with 

proper maintenance throughout. The point of failure for the third failing engine would determine 

the median lifetime for the engine family. The appropriate useful-life selection would be the 

nominal value that is at least as high as the measured median lifetime. Manufacturers would 

need to use good judgment in making a determination regarding the point of failure, including 

consideration of the cost and ease of repair in the case of component failure and including 

consideration of equipment performance in the case of reduced power output (from lost 

compression, for example). It would not be appropriate to consider a piece of equipment to be at 

the end of its lifetime if a typical consumer with access to a reliable mechanic would have it 

repaired or would otherwise continue using it. We would not accept the idea that a typical 

consumer would as a matter of course dispose of equipment where an evaluation of the cost of 

maintenance would justify continued use of the equipment instead of purchasing a new unit. 

2.4.3 Other labeling issues 

What Commenters Said: 

EMA commented that EPA must recognize the fact that in order to fit on products that 

typically are small, engine/equipment emission labels for Small SI engines are very small by 

necessity. Given the small size of the emission label, EPA should reconsider the labeling 

requirements incorporated in the final rule. EPA should only require the most relevant 

information to be on the label. Currently, the NPRM requires that the engine/equipment 

emissions label include all of the following information: a numerical designation of the emission 

durability period; Family Emission Limit (FEL); rated or intermediate speed; identification of the 

emission control system; adjustment/tune-up information; altitude kit requirements; fuel and 

lubricant requirements; and winter use identification. The inclusion of all of this information is 

not only impossible due to the size of the label, but unnecessary. Most of the information 

required to be included on the label by the NPRM is information that is included in the 

certification application and more appropriately included in the owner's manual. In addition, 

emission labels are easy to counterfeit and the presumption that the inclusion of such additional 

information will prevent or dissuade counterfeiting is not valid. 

2-49 
Chapter 2: Small SI Engines 

EMA believes the information provided on an engine/equipment emission label must be 

easily read and understood. If EPA requires too much information on such a small label, the 

label will become cluttered, the size of the print will be extremely small, and the label will be 

difficult to read. Adding to the content of the label will not ensure compliance. In fact, adding 

additional content to the label will thwart EPA's labeling goals because it will prevent the easy 

identification of (i) the engine/equipment manufacturer; (ii) compliance applicability; and (iii) 

date of manufacture. EMA commented that in order to ensure a label that is effective, and easy 

to read and understand, the emission labeling requirements should be limited to the inclusion of 

the following important information: 

a. Manufacturers corporate name or trademark 

b. Engine family name (exhaust)/ evaporative code (evap) 

c. Date of manufacture (month and year) unless it is stamped or engraved elsewhere on 

the engine/equipment 

d. The following statements of compliance (where applicable, the word "engine" would 

be replaced with the word "equipment"): 

i. Exhaust - "This engine complies with U.S. EPA Exh. Stds." 

ii. Evap. - "This engine complies with U.S. EPA Evap. Stds." 

iii. Exhaust & Evap. - "This engine complies with U.S. EPA EXH/EVP STDS." 

EMA commented that the proposed requirement to include the FEL on the emission label 

is not acceptable because it precludes the manufacturer from (i) accurately representing the FEL 

(in the CARB PLT Credit situation); and (ii) making necessary retroactive changes to an FEL 

level. In addition, this requirement will impose an undue burden on both engine and equipment 

manufacturers because it will require the manufacturer to create new labels (and dispose of old 

label inventory) every time an FEL is changed, and to maintain both original and supplemental 

labels. The addition of the FEL to the engine label does not add information that is valuable to 

the equipment manufacturer, the ultimate purchaser, or EPA, and creates additional unjustified 

burden on the manufacturer. For these reasons, and in light of the limited available space on the 

engine label, manufacturers should not be required to include the FEL on the engine label. 

EMA commented that due to the limited size of the engine label, information that is more 

appropriately included in the owner's manual should not be required to be included on the 

emission label. They commented that EPA should require the following information to be 

included in the owner's manual instead of on the emission label: (i) identification of the emission 

control system; (ii) adjustment / tune-up information; (iii) altitude kit requirements; and (iv) fuel 

and lubricant requirements. 

EMA is opposed to the new emission label requirements for winter exclusive engines. 

Winter exclusive engines are uniquely configured to run in cold climates (e.g., they do not 

typically have air cleaners, and often have winter calibrations and hot air ducting), and would not 

run well or last long in other types of applications. Winter exclusive engines already are 

adequately identified and discernable from non-winter exclusive engines by the engine family 

name, and the engine manufacturer's scheme for encoding this information into their family 

naming convention. Accordingly, EMA commented that there is no need to include this 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

information on the label. Such a requirement would unnecessarily take up space on an already 

crowded label. 

EMA also opposed the additional requirement to identify rated or intermediate speed 

application restrictions on the emission label. This information does not add any value to the 

label content and should therefore be eliminated. 

If EPA determines that it is necessary to identify delegated assembly engines on the 

emission compliance label, EMA commented that EPA should only do so with the use of an 

identifying mark on the permanent label, such as "DA" as an approved abbreviation for 

"delegated assembly." 

Wherever possible, EMA commented that EPA should strive to minimize differences 

between EPA's and CARB's labeling requirements. The NPRM requires the following emission 

label heading: "EMISSION CONTROL INFORMATION"; while CARB requires either 

"IMPORTANT ENGINE INFORMATION" or "IMPORTANT EMISSION INFORMATION". 

There is no valid reason for EPA and CARB to have different emission label heading 

requirements. As such, EPA and CARB should align on this issue. In the past, EPA has 

accepted CARB label headings as an approved alternative. EMA urged EPA to include the 

CARB heading as an option in the final rule in order to avoid confusion and the need for 

additional approvals to achieve this critical alignment. 

EMA believes the emission label is the appropriate location for identification of the 

manufacturer responsible for compliance and related emission warranty requirements. However, 

the NPRM appears to preclude those engine manufacturers that certify a complete engine (e.g., 

both exhaust and evaporative requirements) from using an integrated emission compliance label. 

EMA commented that engine manufacturers certifying a complete engine should be allowed to 

label products using a single emission compliance label. If the equipment manufacturer is the 

party responsible for introducing the complete evaporative control system into commerce, the 

equipment manufacturer should be allowed to provide the emission compliance label. 

EMA commented on §1054.135(c)(5) stating that the requirement to include engine 

displacement on the label adds no value to either the customer or EPA and should be deleted 

from the labeling requirements. 

EMA commented on §1054.135(g) stating that the proposed language would preclude 

engine manufacturers that certify a complete engine to both the exhaust and evaporative 

requirements defined in 40 CFR Part 1060 from using a viable integrated label. EMA 

commented that this section should be revised to read as follows: “Manufacturers that certify 

compliance to both the exhaust and evaporative requirements of 40 CFR Part 1054 and 40 CFR 

Part 1060 may meet the labeling requirements using a single label that provides all of the 

required information from both parts.” 

EMA commented on §1054.136 “How must I permanently label the equipment I 

produce?” EMA commented that this section is redundant and should be deleted. 

Honda requested that EPA reconsider the entire proposed requirements for engine 

labeling. Honda’s evaluation of the proposed label and contents that would be required for many 

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Chapter 2: Small SI Engines 

engines indicated that the label size and content would be significantly increased due to 

declarative statements and other label information, with little or no added value. Honda believes 

that a simplified label with the certifying organization identification or logo, engine 

manufacturer identification (corporate name or trademark) and a single alpha-numeric designator 

could fully signify engine regulatory compliance. 

Honda commented that the information on a certification label has extremely limited 

value to anyone in the supply chain other than a U.S. Customs or EPA Inspector attempting to 

match the manufacturer and engine with a specific Certificate of Conformity and that engine’s 

certification information. Furthermore, they believe the emission label information is of limited 

value to the engine purchaser, both individual and corporate, because they rely in their purchase 

decisions on business-relevant information such as model and engine type or catalog number 

which are typically stamped in the engine block or on another label. Fundamentally, the 

emission label does not receive any level of attention by or provide any usefulness to buyers or 

users, regardless of unit production volume. 

Honda recognized EPA’s concern for counterfeiting of labels, but they do not believe that 

EPA’s proposal will prevent counterfeiting. Honda also recognized EPA’s desire to provide 

distinction between uncertified and certified products. Nevertheless, they believe there is a much 

better and effective approach to addressing these two needs than merely expanding the 

information on a label. Specifically, Honda suggested that EPA work with industry to establish 

revisions to the certification application that would provide data for an EPA database that could 

be electronically accessed by those with a need to know (U.S. Custom’s inspectors) and 

correlated with information that is part of the engine itself, e.g., stamped engine identification 

information or an engine identification number on the label. Perhaps the month and year of 

engine manufacture would be a necessary supplement if the manufacturer does not maintain a 

readily available database of serial number and corresponding date of manufacture. However, 

the manufacturer name on the label may also be redundant since it is typically on the engine 

itself and also coded into the engine family name. 

OPEI noted that EPA’s regulatory language states the label must contain month and year 

of manufacture with no allowance for variation (see 1060.135(b)(2) and 1054.135(c)(6)). OPEI 

commented that the minimum requirement should be month and year. Production time intervals 

less than a month should also be allowed, for example, week or day. OPEI also requested that 

the date of manufacture be allowed in a code on the label. (For example A06 means January 

2006, B06 means February 2006.) OPEI stated that EPA currently allows for coded date of 

manufacture and should reflect this in the regulatory language. 

OPEI commented that EPA has set precedence in the past for allowing for the deletion of 

the specific model year on the label and replacing it with a term like “this product complies with 

EPA Phase 2 standards” or “this product complies with EPA standards for 2002 and later.” 

Since Class III, IV, and V handheld products have no exhaust changes, OPEI requested that EPA 

add language to §1054.135(c)(12) that will allow the use of standard language that will not need 

pre-approval for EPA such as: “THIS ENGINE COMPLIES WITH U.S. EPA PHASE 3 

REGULATIONS FOR ...” or “THIS ENGINE COMPLIES WITH U.S. EPA EXHAUST 

REGULATIONS FOR 2010 AND LATER MODEL YEAR” 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

EMA 0691 

Honda 0705 

OPEI 0675 

Our Response: 

All the information that we proposed to require on emission labels relates fundamentally 

to compliance with emission standards. This information is useful in varying degrees to 

consumers, equipment manufacturers, and EPA and Customs inspectors. We also note that 

manufacturers have been successful so far in creating and applying labels with all the 

information we require under the current regulations, without creating confusion or otherwise 

thwarting our labeling goals. Nevertheless, we agree with the suggestion in the comments that 

we should pursue alternative means to make some of this information available. In large part, 

our interest in narrowing the required label content is based on the disproportionate amount of 

time it takes to handle requests for variations from the regulatory specifications. As a result, we 

have gone through the effort to reduce the required label content to the minimum needed for the 

label to ensure compliance, given our (and the manufacturers’) current and projected abilities to 

manage the additional information. By reducing the label content in this way, we believe we 

have also reached a point at which we can disallow any variations from the specified label 

content for these few pieces of information. This will significantly streamline the preparation, 

review, and approval of emission labels. 

We generally agree with EMA’s assessment regarding the essential elements of the 

emission label. The manufacturer’s corporate name and the applicable family identification must 

be included. Manufacturers may add their trademark, but this is not required. The date of 

manufacture must be included, unless it is stamped or engraved elsewhere on the engine. A 

modified compliance statement must be included, as described below. We believe the label 

should include two additional items. First, as described in Section 2.4.2, the label must identify 

the engine’s useful life. Second, if the family includes engines with differing displacement 

values, the displacement of each engine should be identified on the label. This would be the only 

way to readily determine which standards apply to each engine since the displacement 

information embedded in the engine family name would not necessarily apply. If manufacturers 

want to avoid separately identifying displacement information on the label in this situation, they 

could simply certify the engines in different engine families. 

Further reducing content to include only a code for looking up all the information may be 

possible in the future, but we believe the EMA comments represent a more realistic middle 

ground for the foreseeable future. A label with nothing but a code for looking up relevant 

information would prevent the label from having any value without being able to access the 

database. We believe there will be times when owners, equipment manufacturers, and EPA and 

Customs inspectors should be able to identify the basic engine and compliance information by a 

simple visual inspection of the engine. 

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Chapter 2: Small SI Engines 

The label items included in the proposal but not in the final rule can be appropriately 

included in the owner’s manual. This includes the identification of the emission controls system, 

tune-up specifications, information related to operation at high altitude, fuel and lubricant 

specifications, limitations on engine use at rated or intermediate speeds (if applicable), and 

limitations on engine use in wintertime equipment (if applicable). 

While the owner’s manual is useful for identifying these additional items, this is of little 

value to EPA or Customs inspectors or even to owners if they don’t have or don’t use the 

owner’s manual, as is commonly the case. To address this concern, we may pursue system 

improvements that would allow us to readily access the database that includes this information. 

In this scenario, an inspector with a laptop or handheld device with Internet access would be able 

to use the engine family identification number to quickly look up all the highlighted information 

that is relevant for a given engine. This would allow us to create a very accessible virtual label 

without being constrained by space limitations. 

As described in Section 2.4.1, we agree that emission labels do not need to include the 

applicable family emission limit. This is based on the alternative requirement to track changing 

family emission limits by date of manufacture and serial number rather than the reasons 

identified by the commenters. 

See Section 1.3.2 for a discussion of build dates on labels, compared with engine 

manufacturers keeping records with this information. We agree that build dates should be based 

on identifying the month and year at a minimum. We don’t believe it is appropriate to use coded 

information to identify the build date. This is especially important given the discretion we are 

allowing to create family codes for compliance with evaporative emission standards, as 

described in Section 4.6. Identifying the full month and year would be preferred (e.g., February 

2009). We would also find standard abbreviations acceptable, such as Feb 09 or 02/09. We 

intend to pursue regulatory amendments to clarify the format of build dates on engines or 

emission labels, with the goal of adopting uniform specifications across all our programs. 

Fundamental to certifying engines under the Clean Air Act is the idea that the certificate 

is valid for a given model year. Manufacturers must recertify all their engines for every new 

model year. In some cases a manufacturer may produce certified engines in a given year and not 

renew certification for the following year. This is a case where the model year information 

would be necessary to identify the compliance status of the engines properly produced under a 

valid certificate and to avoid improperly labeling for the engines produced when there was no 

valid certificate. We are also adding regulatory language to ensure that manufacturers properly 

align their build dates and overall production periods with the dates defining the model year for 

the particular engine family, as identified by the effective dates for the certificate. See Section 

1.5.2 for further discussion of issues related to build dates and model years. 

The information related to wintertime use and rated-speed/intermediate-speed operation 

is mostly intended for equipment manufacturers to ensure that engines are installed in equipment 

consistent with any applicable limits on the engines’ certification. We believe these items should 

be included in the owner’s manual for completeness. We also separately require that engine 

manufacturers make clear in their installation instructions that equipment manufacturers install 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

engines such that they remain in a certified configuration if there are any limits on the range of 

applications covered by the certificate. 

We agree that an abbreviation for “Delegated Assembly” may be necessary. However we 

believe the abbreviation should be no shorter than “DEL ASSY”. Such an abbreviation will 

allow for continued recognition of the terms for an informed reader/inspector, without resorting 

to a two-letter code that could ultimately be overlooked or misunderstood. This is especially 

important given the discretion we are allowing to create family codes for compliance with 

evaporative emission standards, as described in Section 4. 

As described above, our primary motivation to reduce the label content as much as 

possible is to standardize labels and avoid requests for alternative wording and formatting. 

Accordingly, we do not believe it is necessary or appropriate to create a path for alternative 

labeling for the label heading. Our understanding is that California has agreed to allow 

manufacturers to meet their requirements with EPA’s label heading, so this should not be an 

issue under the Phase 3 program. 

We believe the proposed language in §1054.135(g) clearly and explicitly allowed 

integrated manufacturers to use a single label for meeting requirements for compliance with both 

exhaust and evaporative standards. We have nevertheless modified the wording to align with the 

language suggested in the comment. 

We agree that the proposed §1054.136 does not add new requirements and is not 

necessary for highlighting other requirements that apply for equipment manufacturers. We have 

removed this section for the final rule. 

2.4.4 Maintenance 

What Commenters Said: 

OPEI noted that the maintenance provisions for handheld engines are outlined according 

to §1054.145(c)(3). This paragraph allows the continued use of maintenance provisions outlined 

in EPA Phase 2 for certification and deterioration factor (DF) engines. OPEI also noted this 

provision has no expiration date. OPEI further noted that the maintenance provisions outlined in 

1054.125 do not apply to handheld engines. OPEI requested that EPA add language to 1054.125 

indicating this section does not apply to handheld engines. 

EMA and OPEI commented that EPA should allow the following critical emissionrelated maintenance practices during the determination of deterioration factors based on the 

maintenance schedule provided to users: air filter, spark plug, valve lash adjustment, and twocycle exhaust port carbon removal. These practices are well understood in the market place and 

have been utilized for many years in order to ensure that engines perform their intended function 

for their expected lifetime. EMA and OPEI also commented that EPA should explicitly 

acknowledge that the following maintenance practices are critical emission-related maintenance 

that cannot be conducted during the determination of deterioration factors: internal combustion 

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Chapter 2: Small SI Engines 

chamber deposit removal, valve or valve seat reconditioning (including lapping, grinding, or 

cutting), and replacement of exhaust aftertreatment components. 

EMA commented that air filter maintenance generally is prescribed by the engine 

manufacturer for all customers. Such maintenance instructions typically include provisions that 

address adverse environmental conditions that may require more frequent maintenance. 

Depending on the air filter design, such maintenance could include cleaning or replacement. 

Engine deterioration factor determination must be allowed to utilize the maintenance as 

prescribed to the customers operating in a clean environment typically utilized for engine aging. 

EMA commented that if there is a concern that manufacturer defined maintenance 

intervals are too close to prescribed emission testing points, the final rule should require both 

pre- and post-maintenance emission tests on a case-by-case basis. For example, CARB requires 

pre- and post-maintenance testing if the emission test point is within 10 hours of the prescribed 

maintenance. 

EMA commented on §1054.125(a) “What maintenance instructions must I give to 

buyers?” EMA commented that the requirement to demonstrate that scheduled maintenance is 

reasonably likely to be performed is impractical. Small SI engine maintenance is typically done 

by either the owner or an independent dealer. For the individual home owner, maintenance 

intervals are typically dictated by seasonal time and use patterns. However, the same engine 

utilized by a semi-commercial owner/operator may be serviced routinely on a use basis. Typical 

maintenance not covered by defect warranty that involves cleaning (such as air filters) or 

adjustment (such as valve clearance) do not generate any documentation available to the engine 

manufacturer. Generically available items (such as spark plugs) are impractical for engine 

manufacturers to document due to the sheer number of suppliers and retail outlets selling such 

merchandise. EMA believes a limited and explicit list of acceptable emission-related 

maintenance must be identified in the final rule, along with a provision that allows engine 

manufacturers to demonstrate why additional critical emission related maintenance not specified 

in the rule should be allowed. EMA commented that allowable critical emission-related 

maintenance during service accumulation and emissions durability determination should include 

air filter cleaning/changes, valve lash adjustment and spark plug changes. The frequency of this 

maintenance must be consistent with the engine operator’s manual. EMA commented that 

internal engine maintenance, such as decarboning of the engine combustion chamber, re-seating 

of the valves, or other maintenance should explicitly be included in §1054.125(a)(2). 

EMA commented that the parts identified in §1054.125(d) “What maintenance 

instructions must I give to buyers?” must be revised in order to agree with the proposed revisions 

to §1054.125(a). Further, the second sentence should be revised to read as follows: “Noncritical 

emission-related maintenance generally includes re-seating valves, removing combustion 

chamber deposits, or any other maintenance related to emission-related parts as specified in 40 

CFR Part 1068, Appendix I.” 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

EMA commented on §1054.125(e) “What maintenance instructions must I give to 

buyers?” EMA commented that based on the proposed language in §1054.125(a), valve lash 

should be removed from the list of potential non-emission related maintenance. 

EMA commented on the definition of critical emission-related components set forth in 

§1054.801. EMA commented that the proposed definition does not include air filters or spark 

plugs. They noted that such parts are included in the definition of critical emission related parts 

elsewhere in the proposal. 

Kohler commented that it has concerns with the current maintenance allowed during DF 

testing in Part 90 and the wording in the proposed regulation §1054.125(a). Kohler commented 

that normal maintenance should be allowed to be required in the owner’s manual without 

performing surveys etc. Any maintenance such as changing sparkplugs, air filters, and oil are all 

normal and accepted by industry and should not require any special survey or demonstration on 

the part of the manufacturer to be allowed to include them as a requirement in the manual. 

Kohler noted that §1054.125(d) states that you cannot change an air filter or sparkplug 

during service accumulation. Kohler commented that this statement needs to be changed to “you 

cannot change an air filter or sparkplug during service accumulation for DF testing at intervals 

different than that specified in the owners manual.” 

CARB noted that EPA proposed to allow emission-related maintenance during DF testing 

if “60 to 80 percent of in-use engines get the specified maintenance at the recommended 

interval.” As noted in the preamble, the small spark-ignition engines are predominantly operated 

by homeowners and experience widely varying service practices. To ensure that the DFs do 

actually represent in-use engines, it is crucial that maintenance that is not likely to be performed 

in-use is not allowed for test engines. To strike a balance, CARB recommended alignment with 

other maintenance-related provisions that were adopted recently for the on-road heavy-duty 

category requiring an 80 percent survey and other provisions. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

Kohler 0703 

EMA 0691 

Our Response: 

We agree that the maintenance provisions of §1054.125 do not yet apply to handheld 

engines (as specified in the proposed §1054.145(c)(3)). This is necessary because we are not 

changing the stringency of the exhaust emission standards for handheld engines. Changing the 

allowable maintenance during service accumulation for certification could affect emissions in a 

way that would effectively change the emission standards for those engines. We expect to apply 

the provisions of §1054.125 to handheld engines without modification when we adopt the next 

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phase of standards for those engines. We therefore agree that it is appropriate to add a note to 

§1054.125 to clarify that the maintenance provisions of that section do not apply to Phase 3 

handheld engines. 

We also agree that the regulations should clearly disallow removal of combustion 

chamber deposits, reconditioning of valves and valve seats, or replacing aftertreatment 

components. These would rarely be performed as normal maintenance practices by owners so 

they should also not occur during service accumulation for certification. We note too that we 

have no reason to believe that carbon removal from exhaust ports on two-stroke engines can be 

considered normal maintenance, so we do not believe that would be an appropriate maintenance 

step during service accumulation. We expect that all two-stroke engines certified to Phase 3 

standards will be handheld engines. As described above, the provisions of §1054.125 do not 

apply to handheld engines, so we will revisit the question of maintenance for these engines when 

we adopt the next phase of standards. We do not expect to allow carbon removal from exhaust 

ports during service accumulation unless there is clear evidence demonstrating that this 

maintenance is typical for in-use engines. 

It is clear that some owners clean or replace air filters and spark plugs on the schedule 

prescribed in the owners manual. This would be the case for fastidious homeowners wanting to 

make their equipment last as long as possible or commercial owners interested in reducing the 

costs associated with repairing or replacing aged equipment. We remain unconvinced that in-use 

maintenance related to air filters and spark plugs is so prevalent that manufacturers should 

perform these maintenance steps during service accumulation. There are surely many owners 

who, perhaps in spite of best intentions, fail to invest the time, effort, and expense of preventive 

maintenance. There is clearly some tendency to treat Small SI engines and equipment as 

disposable items, running with minimal maintenance until a problem surfaces, then evaluating 

whether to make a repair or just replace the equipment. Especially with low price-point 

consumer products, repair costs (and even some preventive maintenance costs) would be high 

enough that many owners would minimize maintenance and repairs and opt instead to purchase a 

replacement model after a few years. Even for commercial operations, Small SI equipment 

many times would represent a small part of a much larger operation. As such, companies 

operating these engines would in many cases not make it a priority to coordinate a regular 

schedule of preventive maintenance. For both homeowners and commercial users, we believe 

the likelihood of taking preventive maintenance steps on the prescribed schedule falls 

dramatically after the first year of service (or for second owners). Performing a survey to 

establish current maintenance practices would be very helpful, but we understand the constraints 

on getting this information described in the comments. 

Limiting maintenance during service accumulation for certification to align with the 

prevailing in-use practice is important to avoid a situation where manufacturers are able to 

achieve the necessary level of emission control in the laboratory while in-use engines are 

emitting at higher levels because these same maintenance steps are not being done. To the extent 

that maintenance might not be performed in the field, manufacturers should have the incentive to 

design their engines such that they do not depend on this maintenance to comply with emission 

standards. For example, as described in the proposal, we are concerned that air filters may 

become coated with oil mist on the downstream side. Intake systems can be designed to prevent 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

this by carefully designing the pressure dynamics of the intake system and the venting of 

crankcase gases (and oil mist) into the intake system to prevent the entrained oil from reaching 

the back side of the air filter. In contrast, if we allow routine air filter changes as prescribed in 

the owners manual, there is no need to improve these designs, even though the problem would 

occur with any in-use engines that do not get the scheduled filter changes. 

Having said that, we also note that our testing to establish the feasibility of the proposed 

standards involved a rigorous effort to perform maintenance as prescribed in the respective 

owners manuals, which generally involved air filter maintenance every 25 hours and spark plug 

changes every 100 hours. Based on this experience, we don’t believe we should entirely 

disallow these maintenance steps for certification for demonstrating compliance with the Phase 3 

standards. We therefore believe it would be appropriate to allow manufacturers to clean or 

change air filters and spark plugs, as long as manufacturers perform emission measurements 

before and after these maintenance steps. It would be best to perform testing after each 

maintenance step; however, we would find it acceptable if manufacturers tested engines before 

and after maintenance after every other air filter change. Manufacturers would use the average 

of these two results for calculating deterioration factors. However, every measured test point 

would need to be under the emission standard to be considered in compliance. This approach 

allows for continued performance of these maintenance steps, consistent with our feasibility 

testing, but properly identifies the effect on emissions. 

Most Class I engines are certified with a useful life of 125 hours. Since manufacturers do 

durability testing halfway through the useful life, this would be a normal point of replacing the 

air filter. If manufacturers specify filter replacements every 25 hours, this would involve only a 

small adjustment to fit with the planned testing. If manufacturers specify filter replacements 

every 25 hours, they would need measure emissions before and after changing the air filter after 

the second filter change at 50 hours, or they could opt for a 30-hour filter change interval and 

simply test at the scheduled midpoint for service accumulation. 

Laboratories where service accumulation occurs generally have very little dust or 

airborne debris that is common in the in-use environment. We believe it is well within reach for 

manufacturers to design their engines for extended operation without needing cleaning or 

replacement of air filters. We believe this approach properly balances the manufacturers’ 

interest of performing maintenance during certification with our interest of documenting the 

emission effects of this maintenance and maintaining the incentive for manufacturers to design 

their engines to be dependent on maintenance as little as possible. 

Some Class I engines and all Class II engines are certified with a useful life of 250 hours 

or longer. Testing these engines at the midpoint of their service accumulation involves a 

correspondingly longer period. At the extreme, a 1000-hour useful life would involve testing 

after 500 hours of operation. To avoid additional test points, manufacturers would need to 

design their engines to meet standards without cleaning or changing air filters for 250 hours or 

spark plugs for 500 hours. While this involves a greater challenge, we think it is even more 

achievable for these engines where the reduced price sensitivity does not impose such a 

challenging constraint in properly designing and manufacturing these engines. We believe these 

longer useful-life engines should be capable of operating on a controlled test fuel in a controlled 

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environment for 250 hours without servicing air filters and for 500 hours without replacing spark 

plugs. However, as described above, we believe it is appropriate to allow for more frequent 

service as long as the manufacturer performs emission tests before and after the maintenance to 

document the effect on emissions. 

In pursuing more stringent emission standards in the future, we intend to more carefully 

demonstrate the feasibility of achieving effective emission control over the full useful life with 

maintenance intervals that more appropriately reflect any reduced level of service that may be 

typical of the in-use experience for Small SI engines. We would then be able to set more careful 

limits on the maintenance that manufacturers may perform during service accumulation such that 

certified engines will not depend on maintenance that may not be occurring with in-use engines. 

We have modified §1054.125 and §1054.801 to include air filters and spark plugs as 

critical emission-related maintenance. 

Consistent with the proposal and all our other programs, we believe that adjusting valve 

lash is not emission-related maintenance. Including valve-lash adjustments in §1054.125(e) 

allows manufacturers to perform this maintenance during service accumulation at the least 

frequent interval specified in the owners manual. This approach addresses the manufacturers’ 

interest in performing this maintenance on their recommended schedule. 

The first four paragraphs of §90.118 were adopted as part of the initial phase of 

standards, in which there was no service accumulation beyond engine stabilization. When part 

90 was modified for the Phase 2 standards, there were no changes in the regulation to add 

specific requirements or prohibitions related to maintenance during the service accumulation 

period between stabilization and the end of the useful life. As such, we have concluded that only 

oil and filter changes may be done before stabilization is complete, and manufacturers may 

follow the scheduled maintenance specified in the owner’s manual for the rest of the serviceaccumulation period. 

2.4.5 Deterioration factors/bench aging 

What Commenters Said: 

OPEI and EMA commented that EPA should allow for the future development and use of 

an aftertreatment bench aging procedure. However, due to the complexity of such development, 

the limitations and appropriateness of any procedure must adequately be assessed. 

OPEI commented that if a manufacturer can show that due to field-testing, the bench DF 

cycle is too aggressive, EPA may approve an alternative test cycle based on data the 

manufacturer provides. 

OPEI noted per CARB requirements that the calculation of a DF must involve at least 

three test points (zero/midpoint and end of test). If a maintenance interval is scheduled at a test 

point, the emission test should be run both before and after the maintenance. The emission test 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

results should then be averaged for the value to be used in the calculation. OPEI commented that 

EPA should specify the same requirement in §1054.245 to avoid confusion. 

CARB commented that operating and testing the complete engine is necessary to get 

accurate deterioration factors (DF). They noted that some manufacturers are using bench-aging 

of components, including catalysts, to identify the worst-case scenario amongst 

models/components. Subsequently, DFs are developed on the worst-case model/configuration 

using full service accumulation on a dynamometer or in-use. CARB commented that benchaging of components and other alternative procedures should be allowed only if manufacturers 

provide adequate correlation data between their aging procedure and normal service 

accumulation. Regarding assigned DFs, CARB commented that these should be limited to just 

California small-volume manufacturers (less than 500 total units per year). Other manufacturers 

are required by California regulations to develop their own DFs so EPA’s use of those same DFs 

would not impose any burden on manufacturers. 

ECO noted that EPA proposed an allowance for small volume engine families to utilize 

assigned deterioration factors and requested input on the use of assigned DFs for small volume 

engine families. ECO commented that this provision is necessary to allow flexibility for small 

volume engine families. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

EMA 0691 

ECO 0712 

Our Response: 

We understand that a bench aging procedure has the potential to provide effective 

deterioration factors at a substantially lower cost compared with aging engines with complete 

systems on an engine dynamometer. As noted in the proposal and reiterated in the comments 

however, we would want to be very sure that a specific bench aging procedure would adequately 

represent aging from complete in-use engines. A fundamental factor in evaluating the 

appropriateness of any bench-aging procedure is the extent to which it simulates representative 

exhaust gas composition and other in-use operating parameters. Any bench-aging procedure 

would therefore need to take into account a wide range of variables to provide an adequate 

simulation. 

We agree that the regulation should be changed to require testing at the midpoint of 

service accumulation. This provides additional information and aligns with the requirements 

already in place in California. See Section 2.4.4 for a discussion of issues related to maintenance 

during service accumulation. 

We continue to believe it is appropriate to include a provision for assigned deterioration 

factors for small-volume engine families, even if the certifying company is not a small business. 

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There may be several cases where the manufacturer produces only engines for equipment that is 

preempted from California regulations, or that is not sold in California at all. We agree that it is 

not helpful to allow for assigned deterioration factors where the engine manufacturer will have to 

develop its own deterioration factor for the same engine family in California. However, we 

would not want to disallow the use of assigned deterioration factors for those small-volume 

engine families where the manufacturer does not need to do service accumulation to establish a 

deterioration factor for California. 

2.4.6 Warranty 

What Commenters Said: 

EMA commented that engine manufacturers must have the ability to shorten emission 

warranty periods for engines that accumulate hours at a high rate such that they exceed 50% of 

their specified emission durability period prior to the expiration of the prescribed emission 

warranty period. 

EMA commented that the proposed emission related warranty parts list requirements 

duplicate the information provided in 40 CFR Part 1068, Appendix I. They recommended that 

the emission related parts list be inclusive of the emission related components identified in the 

certification application, which also references 40 CFR Part 1068, Appendix I. 

EMA commented that for engines certified using aftertreatment or intake systems 

supplied by the equipment manufacturer under the delegated assembly provisions defined in 

§1054.610, that the warranty requirements be transferred to the equipment manufacturer. Engine 

manufacturers should be required to maintain a cross reference such that any customer request 

for warranty associated with a component provided by the equipment manufacturer would be 

referred to the appropriate equipment manufacturer. 

EMA commented on §1054.120 “What emission-related warranty requirements apply to 

me?” EMA commented that the regulations should be revised in order to clarify to whom the 

section applies. Specifically, they recommended that the section be revised to read as follows: 

“The requirements of this section apply to the manufacturer that certifies compliance with the 

exhaust emission requirements of this part. See 40 CFR Part 1060.120 for evaporative emission 

warranty requirements.” 

EMA noted that under §90.1103(a), the warranty period should begin on the date of sale 

to the ultimate purchaser. Accordingly, EMA commented that the sixth sentence of 

§1054.120(b) “What emission-related warranty requirements apply to me?” should be revised to 

read as follows: “The warranty period begins on the date of sale to the ultimate purchaser.” 

They also commented that this section should provide an option for decreased warranty period in 

order to provide a differentiation between consumer and commercial usage of non-handheld 

products similar to what is provided for handheld equipment in §1054.120(b)(2). Finally, EMA 

commented that EPA should add the following language as §1054.120(b)(4): “Any end user that 

purchases a Consumer Product and uses it Commercially will have a shorter warranty period.” 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Honda commented that nonhandheld engines in commercial equipment should also 

specifically have the same option granted for handheld seasonal equipment, to limit the warranty 

time period based on the product’s use even without an engine or equipment hour meter. This 

suggestion is made in reference to §1054.107. Honda noted that it is in §1054.120(b)(2) where 

EPA has made an allowance for the seasonal use of handheld equipment. The regulations state, 

“We may establish a shorter warranty period for handheld engines subject to severe service in 

seasonal equipment if we determine that these engines are likely to operate for a number of hours 

greater than the applicable useful life within 24 months. You must request this shorter warranty 

period in your application for certification or in an earlier submission.” EPA has in this section 

recognized that commercial equipment is very likely to be used for many more hours in less 

calendar time than would be expected for homeowner operated equipment. 

Letters: 

Commenter Document # 

Honda 0705 

EMA 0691 

Our Response: 

 We believe §1054.120 appropriately defines the engine components that are subject to 

the emission-related warranty. The commenter’s suggestion for the warranty to cover only those 

parts listed in the application for certification would allow manufacturers to avoid warranty 

coverage for a given component simply by leaving it out of the description in the application. 

The broader language included in §1054.120 is necessary to ensure that components will be 

covered even if manufacturers develop an emission control technology with components that 

would not be covered by the specific list given in Part 1068, Appendix I. 

The certificate holder always bears the primary responsibility for ensuring that engines 

have proper warranty coverage. Certifying engine manufacturers may choose to cooperate with 

equipment manufacturers in the interface with owners, but we would hold the certificate holder 

responsible for compliance with warranty obligations. We could also pursue recourse against 

equipment manufacturers, importers, or retailers for having caused the violation if we are able to 

establish that any of those parties did not take basic steps to ensure that there was an effective 

plan for meeting warranty requirements. 

The provision for shorter warranty periods for handheld engines used seasonally in severe 

service can work because the companies making the engines also install the engines in their own 

equipment. They can therefore understand the range of expected operation in the field for their 

certified engines. (We note, however, that no handheld manufacturer has requested this shorter 

warranty for engines used in seasonal equipment.) This is generally not the case for 

nonhandheld engines. Even those manufacturers that also make equipment will sell many loose 

engines from the same engine family to other equipment manufacturers. It is therefore difficult 

to conceive of an engine manufacturer being able to adequately demonstrate the seasonal or 

severe-duty nature of the expected in-field operation. While this may occur for some engine 

installations, there could be many other installations where equipment manufacturers and/or 

owners simply want a more reliable engine for operation that is neither seasonal nor severe-duty. 

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We note too the increasing likelihood that commercial engines will have electronic controls and 

fuel injection. While these will be simple systems, they will include the ability to clock engine 

operating hours. Since we allow for a shorter warranty period based on engine operating hours, 

it would be unnecessary for manufacturers to have any special approval for a shorter warranty 

period based on seasonal and severe-duty operation. 

We don’t believe it is appropriate to specify that a shorter warranty period applies for 

commercial use of products that are intended for consumer applications. Many types of 

equipment are not clearly differentiated between consumer and commercial applications. 

Similarly, a person’s use of any given piece of equipment is many times not easily 

distinguishable between consumer and commercial applications. The suggested language could 

therefore not be clearly applied to adjust warranty periods for these products. As described 

above, we believe the best long-term approach is to anticipate that many or most engines in 

commercial service will have hour meters that will indicate an end to the warranty period based 

on the engine’s operating hours rather than counting months on the calendar. 

We agree that §1054.120 should more carefully state that the section applies to 

manufacturers that certify with respect to exhaust emissions, with part 1060 covering warranty 

obligations with respect to evaporative emissions. We also agree that the warranty period should 

start at the point of sale rather than the date the engine is placed into service, consistent with the 

prevailing practice for standard warranties on consumer products. This avoids a situation where 

owners could make unverifiable claims that they first placed the engine into service several 

months after making the purchase. 

2.4.7 Naming labs and ports for imported products 

See Section 1.3.1 for an analysis of the comments related to the requirements for 

importing manufacturers to identify the ports where they import products and to name a 

laboratory in the United States for testing their engines. 

2.4.8 Engine family criteria 

What Commenters Said: 

OPEI commented on §1054.230(b) recommending that EPA should include in the list 

that families with displacements within 15% can be grouped together. This has been proven 

reliable and acceptable for EPA Phases 1 and 2 as well as CARB Tier I/II/III. 

EMA noted that engine manufacturers producing multi-fuel engines recognize that they 

must evaluate the different fuel influences in order to determine the worst case configuration 

associated with the compliance demonstration for any engine family. EMA commented that it is 

important that engine manufacturers be allowed to utilize their best engineering judgment in 

order to determine which fuel and resulting engine configuration represents the worst case 

configuration for a given family and, therefore, be used for the certification data development 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

process. For example, an engine family may include both propane and natural gas fuel options 

for an engine model, but the engine manufacturer should be allowed to determine the worst case 

configuration for certification testing using their best engineering judgment. 

EMA commented on §1054.230(b) “How do I select emission families?” EMA noted 

that pursuant to 40 CFR Part 90.116(d)(5), engines of different displacements that are within 

15% of the largest displacement may be included within the same engine family. While this 

flexibility is implicit in the proposed rule, EMA requested that EPA include a statement in the 

preamble clearly stating that the intent of the language is to allow engine models of varying 

displacements (such as specified in §90.116) to be combined into one family at the 

manufacturer’s option. 

EMA commented on §1054.230(f) “How do I select emission families?” EMA 

commented that because Part 1054 does not identify the requirements associated with obtaining 

an evaporative certificate of compliance, it is not appropriate for this section to discuss 

evaporative component selection. Because all of the evaporative requirements refer the engine 

manufacturer to Part 1060, EMA commented that it is both redundant and confusing to include 

evaporative requirements within the requirements controlling the exhaust certification process. 

Honda commented that the engine family determination criteria in the final rule should 

state that engines with a 15% displacement difference (percentage based on largest engine) may 

be in the same engine family if they have similar emission characteristics. Honda also 

commented that if a manufacturer can demonstrate that engines with a larger displacement 

difference also have similar emission characteristics, the manufacturer should also be able to get 

approval for inclusion in the same family. 

Letters: 

Commenter Document # 

Honda 0705 

OPEI 0675 

EMA 0691 

Our Response: 

Under part 90 we have approved the combination of engines within a single family if the 

range in displacement is within 15 percent of the largest engine’s displacement. The proposed 

regulatory language for part 1054 specifies that engines must have the same “approximate bore 

diameter of cylinders.” We have adopted this language broadly across most of our programs. 

We are adopting the proposed regulatory language without modification. We believe this is the 

best approach, giving a clear guideline but allowing enough discretion to be able to respond to 

any particular situations that may arise. We will continue to approve combined engine families 

based on the 15-percent displacement threshold. This maintains a harmonized policy with 

California and is generally consistent with the way we have implemented other EPA programs. 

We may also decide in special circumstances that a different threshold should apply. 

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We agree that dual-fuel engines represent a special case for differentiating engine 

families. Clearly one engine that can run on multiple fuels must be in a single engine family. 

The approach EMA describes in which the engine manufacturer chooses the worst-case fuel for 

certification testing is appropriate. We note, however, that an engine that fails to meet the 

applicable emission standards when operating on any of the specified fuels is noncompliant. We 

have revised the regulatory language to clarify that fuel type differentiates engine families, 

except in the case of dual-fuel engines. We have also added a clarification to §1054.235 to say 

that we may require manufacturers to submit data using the fuel not yet included in testing, and 

that such a test would be treated as if it were a second engine rather than a replacement for the 

original data. 

We agree that §1054.230 should reference part 1060 to clarify how to define emission 

families with respect to evaporative emissions, rather than including that information directly. 

The final regulations have been changed accordingly. 

2.4.9 Other certification issues 

What Commenters Said: 

OPEI noted that EPA is asking manufacturers to report CO2 in §1054.205(p). OPEI 

questioned why EPA was asking for the information and commented that if EPA wants CO2 

reported, then manufacturers should be provided with requirements on how it should be reported 

(units, calculation etc). 

OPEI commented that under paragraph 1054.640(c), if the manufacturer is responsible to 

EPA, then paragraphs (a) and (b) are an unnecessary burden and should be deleted. 

EMA commented that EPA should clarify where in the certification application the 

additional information required by §90.107(d)(11)-(15) should be included. 

EMA commented on §1054.130 “What installation instructions must I give to equipment 

manufacturers?” EMA commented that installation instructions for equipment that is not subject 

to the provisions of the delegated assembly requirements in §1054.610 should be limited to 

features consistent with the requirement to assure that the engine is in its certified configuration. 

EMA noted that these instructions are generally not explicit instructions, but rather a process 

used by engine manufacturers to approve the use of their engine in any equipment according to 

the engine manufacturer’s requirements. For example, exhaust back pressure or intake air 

temperature rise may be specified to assure emission compliance and also expected performance. 

Accordingly, EMA commented that this section should be substantially revised to read as 

follows: 

“(a) If you sell an engine for someone else to install in a piece of equipment, make 

available the information required to ensure that as installed the engine will be in its 

certified configuration. 

(b) If the engine does not include provisions to control evaporative emissions advise the 

equipment manufacturer to refer to 40 CFR Part 1060 for applicable requirements. 

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(c) Provide information to the equipment manufacturer that if installation precludes 

visibility of the engine’s emission control label that a duplicate label must be added to the 

equipment in a visible location.” 

EMA commented on §1054.205(o)(1) “What must I include in my application?” EMA 

commented that the reference to THC or THCE should be expanded to include NMHC as 

required by §1054.103(c)(2). 

EMA commented on §1054.250(a) “What records must I keep and what reports must I 

send to EPA?” EMA commented that the requirement to submit volume reports within 30 days 

is inconsistent with current EPA requirements, is not adequately defined, and is inappropriate. 

EMA noted that existing reporting requirements provide manufacturers 45 calendar days for 

reporting. Accordingly, EMA commented that the reporting requirement should be revised to 45 

calendar days. 

EMA commented on §1054.250(b)(4) “What records must I keep and what reports must I 

send to EPA?” EMA commented that it is not practical to require manufacturers to maintain 

production volume records for each engine family by assembly plant. In many cases, there are 

multiple steps in the assembly process that may be completed at different assembly plants 

thereby making this information either meaningless or impractical to determine. EMA 

recommended that this record retention requirement should be revised to require records 

regarding the total production volume for each engine family. 

Kohler commented that a consistent test cycle between engine manufacturers is critical to 

maintaining a level playing field. This applies to both dynamometer emissions testing as well as 

DF hour accumulation. Kohler requested that in the Phase 3 regulation, EPA take action to 

maintain a level playing field for all manufacturers by assigning alphanumeric designators to all 

approved alternative test cycles and posting these to the EPA website. This would include 

alternate procedures for dynamometer testing as well as the approved cycles (speed/load/time) 

for DF hour accumulation. Kohler had the following recommendations for specific language 

modifications. 

§1054.501 (c) Alternate test procedures — EPA allows engine manufactures to request 

approval for the use of an alternate test cycle if they cannot run the test cycle specified in 

this part. If an engine manufacturer requests and receives approval these MUST be given 

an alphanumeric designation and posted on the EPA website and be available for anyone 

to use. 

Kohler noted that §90.104 (h)(2)(ii) currently states that engine manufacturers should . . . 

“Conduct such emission testing again following aging the engine. The aging procedure 

should be designed to allow the manufacturer to appropriately predict the in-use emission 

deterioration expected over the useful life of the engine, taking into account the type of 

wear and other deterioration mechanisms expected under typical consumer use which 

could affect emissions performance. If more than one engine is tested, average the results 

and round to the same number of decimal places contained in the applicable standard, 

expressed to one additional significant figure”. 

Kohler noted that there is no specific aging procedure defined. Many manufacturers today, 

including Kohler, use repetitive cycles of the 6-mode certification test cycle for aging the engine. 

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However, there is no public information available that states what procedure is being used by 

individual engine manufacturers. To maintain a level playing field Kohler requested that the 

following wording be used in the regulation: 

“Conduct such emission testing again following aging of the engine. The aging procedure 

must accumulate service (age the engine) in a way that represents how you expect the 

engine to operate in use and be approved by EPA. EPA’s approval will assign an 

identification code for the cycle to be utilized in the manufacturer’s certification 

application(s) for all applicable engine families. Approved test cycles will be listed with 

their respective identification code on the Small Spark Ignition Certification website and 

available for any applicable engine family. If more than one engine is tested, average the 

results and round to the same number of decimal places contained in the applicable 

standard, expressed to one additional significant figure.” 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Kohler 0703 

Our Response: 

We require manufacturers to submit emission results for CO2 only where those 

measurements are needed to determine emission levels of regulated pollutants. If this 

information is routinely gathered as part of emission testing, there is a minimal reporting burden 

for manufacturers. We want to be able to access this information to help us assess the reported 

results for the regulated pollutants. We have revised the regulation to clarify that these results 

should be reported as brake-specific values (g/kW-hr). 

We believe that the branding provisions of §1054.640 include basic information 

necessary for ensuring that equipment manufacturers will fulfill their warranty obligations. We 

agree that we can omit the requirement for engine manufacturers to describe the specific 

arrangements in their application for certification, but we believe it is necessary for the engine 

manufacturer to formalize the arrangements in the form of a contractual obligation, and it is quite 

appropriate to inform us of all the equipment manufacturers with whom this relationship exists. 

The references to THC and THCE are simply given as examples, so there is no need to 

include NMHC as another example. However, it is not incorrect, so we have modified the 

regulation accordingly. 

We agree with the commenter that installation instructions should be focused on ensuring 

that engines are in their certified configuration after installation in equipment. Our proposed 

regulation included several specific details, such as referencing altitude specifications where 

appropriate, clarifying information related to evaporative emission controls, describing limits on 

installations (such as being certified only for use in rated-speed applications), and adding a note 

that duplicate labels may be necessary. The proposed provisions are well established in many of 

our other programs and they include only as much as we believe is necessary to achieve the 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

commenters stated goal of ensuring that engines are in their certified configuration in the final 

installation. 

We agree with manufacturers that submitting production reports within 45 days after the 

end of the model year is sufficient. 

If it becomes clear that defective engines are limited to production processes or other 

practices at a particular production facility, both we and the manufacturer would want to 

understand how isolated the problem is. This would apply both for applying a remedy and 

assessing penalties, if appropriate. We believe manufacturers should be keeping these records as 

a matter of course for business reasons, so we expect there is no additional burden to keep this 

information. If production is divided into multiple steps across multiple facilities, manufacturers 

should still be able to identify the number of engines that were processed at each facility. 

EMA’s concerns about certifying fuel lines under §90.127 are moot because we are 

revising these requirements to apply to component manufacturers. 

We agree that EPA’s process for approving certification and testing procedures should be 

transparent. However, we believe the best approach for accomplishing this is administratively 

rather than by regulation. We may develop a process consistent with Kohler’s suggested 

approach, but we need to maintain the flexibility to develop and modify those processes based on 

our continuing experiences rather than limiting ourselves to a specific approach in the regulation. 

We look forward to working with manufacturers over time to continue to improve our processes 

for evaluating such requests and communicating the results of this decision-making. 

2.5 Test procedures 

2.5.1 NHH duty cycle/governor 

Comment Response 

EMA commented that the NPRM’s requirement that 

engines operate utilizing the engine’s installed governor 

for the idle mode is not appropriate for many engines. A 

significant percentage of engines in the Small SI 

category do not utilize the engine governor to control 

speed at idle. Such engines utilize a fixed throttle 

position, generally determined by an adjustment screw. 

For engines that do not utilize the governor to control 

idle speed, the test condition should represent the 

expected in-use idle speed control condition rather than 

the governor. 

We agree that the regulations should reflect the situation 

in which no engines in the family have governors that 

control idle speed. The definitions and testing 

provisions in part 1054 and part 1065 specify that 

engines without governors controlling idle speed should 

be set at the idle speed declared by the manufacturer. 

§1054.235(c)(4). EMA commented that it is impractical 

to recalibrate an emission test engine within normal 

production tolerances as described in this section. 

§1054.235(a) requires the test engine to be selected 

based on the identified criteria and to be “tested as they 

will be produced”. Artificial modification via 

recalibration is an overly broad requirement that should 

not be granted to EPA to use in its discretion. EMA 

commented that this provision should be deleted. 

The proposed provision is limited to items that are not 

considered adjustable parameters. As noted in the 

definition of the term, this might include adjustments 

that are not emission-related or that manufacturers ask 

us to exclude. To the extent that production tolerances 

allow for varying engine settings, these items should be 

subject to calibration settings such that the testing 

configuration represents the full range for in-use 

engines. This provision is already in place under 

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Chapter 2: Small SI Engines 

§90.119(b)(2)(iii). 

§1054.501(b)(1). The reference to engines without 

throttle control is confusing and inappropriate. As 

properly defined elsewhere in the proposed rule, the 

engines in this category are generally considered 

constant speed engines for emission testing purposes. 

Engines in this category can have a wide variety of 

controls including: (i) no user control of speed, (ii) user 

control of the maximum speed, and (iii) load sensitive 

automatic idle speed. EMA commented that this section 

should be revised to eliminate the first portion of the 

second sentence that it reads as follows: “See 40 CFR 

Part 1065.10 for instructions for using alternate 

procedures if utilizing the procedure specified in 

1054.505 would result in emissions that do not represent 

in-use emissions.” 

We agree that the provisions in question are best 

addressed elsewhere. We have removed the text in 

question from §1054.501(b)(1). See §1054.650 for 

provisions related to certifying engines without 

governors or with variable-speed governors. 

§1054.501(b)(3). EMA commented that the proposal 

disallowed correcting emissions for the effects of 

humidity. EMA commented that this restriction is not 

consistent with EPA’s current requirements as set forth 

in §90.419. Many laboratories do not have EPA’s 

ability to run at a controlled humidity. Accordingly, 

EMA commented that the humidity correction factor for 

NOx emissions calculated per §1065.670 should be 

required for a valid emission test. 

We agree that the humidity correction in §1065.670 is 

appropriate for Small SI engines. We have revised the 

regulations accordingly. 

§1054.501(d). EMA commented that engine 

manufacturers must be allowed to use good engineering 

judgment in order to determine engine changes 

associated with the prescribed emission test temperature. 

The ambient emission test conditions are not 

representative of in-use conditions for winter exclusive 

products, but ambient test conditions cannot be achieved 

in the test environment that equate to in-use conditions. 

For example, winter exclusive engines cannot operate in 

the prescribed emission test conditions without removal 

or modification of air intake heating systems such that 

intake air temperature during the emission test is 

representative of intake air temperature when the engine 

is operated in-use. EMA recommended that the 

following be added: Engines may be modified for 

emission testing such that intake temperatures are 

analogous to in-use conditions. 

We agree that manufacturers should be allowed to 

remove intake air heaters when testing wintertime 

engines at temperatures between 20 and 30°C and have 

modified the regulations accordingly. We have also 

added a provision allowing manufacturers to test 

wintertime engines at reduced ambient temperatures by 

referencing the existing specifications for snowmobiles 

in §1051.505. In addition, we are adding language to 

§1054.501 to say that non-wintertime engines should be 

tested in a way that properly simulates in-use intake air 

temperatures. We want to avoid a situation where 

manufacturers cool the intake air after it has warmed up 

from exposure to engine heating. This is clearly not 

appropriate since that type of cooling does not occur 

during in-use operation. 

§1054.505(a)(1). EMA commented that the reference to 

40 CFR Part 1065.514 must clarify that these engines 

are considered constant speed engines pursuant to 

§1054.505(b) and therefore only torque statistics are 

required. 

We agree that the reference to §1065.514 should be 

limited to torque-related measurements. There are 

certain modes where manufacturers must control speed 

within certain bounds, but these are specified separately 

in §1054.505. 

§1054.505(c)(2). EMA commented that if EPA does not 

accept our proposed revisions to §1054.801 (see 

comments in Section 2.5.3 below), this section must be 

revised in order to delete the phrase “maximum test 

torque” and replace it with the following language “fullload torque value from §1054.505(d)(2).” 

We agree that §1054.505(c)(2) should reference 

§1054.505(d)(2) for the appropriate torque value, rather 

than relying on maximum test torque as defined in 

§1065.1001. 

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Letters: 

Commenter Document # 

EMA 0691 

2.5.2 HH duty cycle/governor 

What Commenters Said: 

OPEI commented that Max power, as defined in 1054.801 and in 1065.601, are in conflict. OPEI 

commented that EPA needs to make clear that the power from 1054 applies for handheld products during 

the cert test. 

Letters: 

Commenter Document # 

OPEI 0675 

Our Response: 

The regulations specify that maximum engine power is used only for determining 

whether engines are subject to part 1054 requirements or not. Engines are tested based on the 

procedures specified in part 1054, subpart F (including Appendix II), which clarify the load 

settings for full-load operation during the emission test. There are no power definitions or 

specifications in §1065.601, but the other places where there are power specifications in part 

1065 (such as engine mapping in §1065.510) do not apply for handheld engines. 

2.5.3 Maximum test speed 

What Commenters Said: 

OPEI agreed with the reasoning EPA presented for an improved basis in selecting an 

appropriate wide-open throttle speed for emission testing. OPEI believes though that EPA may 

be unnecessarily complicating the regulation with its current language. Handheld products such 

as chain saws, trimmers, brushcutters, edger and hedge clippers (not inclusive) run at wide-open 

throttle speeds in the field that may vary depending on application and load. For example a 

chain saw may be used for debranching, bucking or felling. All which may have slightly 

different loads and resulting speeds. It can be said that these product types will always be 

operating around the max power point but this could vary by several hundred rpm. 

Product that always operates at a fixed speed due to the load of the transmission device 

(like a power blower, pump or generator) should always be tested at the actual operating speed in 

field conditions to get the best real world emission test results. OPEI suggested that the 

definition for rated speed at wide-open-throttle for handheld products be revised as follows: 1) 

Products that always operate at a fixed speed due to the natural load placed on the engine (such 

as power blowers and pumps) should be tested at the real world operating speed, in the 

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Chapter 2: Small SI Engines 

configuration intended for use by the manufacturer, (+/- 350 rpm). 2) For all other handheld 

products (like clippers, trimmers chain saws, edgers etc), the emission test at wide-open throttle 

should be performed at the point of peak engine power (+/- 350 rpm). 

EMA commented on two of the definitions set forth in §1054.801: 1) Maximum test 

speed: The reference should not be to 40 CFR Part 1065.1001, but rather to 40 CFR Part 

1054.505. 2) Maximum test torque: The reference should not be 40 CFR Part 1065.1001, but 

rather to 40 CFR Part 1054.505. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

We believe ungoverned handheld engines should be tested at speeds representing the 

most likely in-use operating speed. We agree with OPEI’s suggested approach for identifying 

the nominal test speed for engines based on whether or not they will be operating in a fixedspeed application. 

We use the term “maximum test speed” in part 1054 only to describe how to test 

governed handheld engines over the two-mode handheld duty cycle. We believe this broadly 

applicable method from part 1065 is appropriate for testing these engines and are therefore 

retaining the definition as proposed. 

We have revised the regulation to avoid using the term “maximum test torque,” since the 

meaning of this term from part 1065 does not apply to Small SI engines. 

2.5.4 Test fuel 

What Commenters Said: 

OPEI, EMA and Briggs and Stratton commented that California Phase 2 Certification 

fuel should be allowed with EPA approved adjustment factors for Phase 2 nonhandheld engines 

as currently practiced for Phase 2 engines. Specifically, OPEI commented that the statement in 

§1054.501(b)(2) should be revised to reflect: “use commercially available fuel representative of 

the fuel that in-use engines would use in the same environmental conditions as the test is 

conducted. Use of CARB Phase 2 fuel is considered acceptable.” EMA commented on 

§1054.501(b)(2) “How do I run a valid emission test?” EPA should explicitly state that 

California Phase 2 Certification fuel may be used with EPA approved adjustment factors as 

currently practiced for Phase 2 engines. Briggs and Stratton added that the proposal does not 

allow for the use of oxygenated fuel, which would include California Phase 2 Certification fuel. 

Alternative test fuels should continue to be allowed. Requiring a change would impose a burden 

on many engine manufacturers with no benefit. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

OPEI’s and EMA’s engine manufacturers proposed that appropriate correction factors be 

developed if the EPA certification test fuel is changed to an oxygenated fuel. Currently EPA 

allows an option for engine manufacturers to use California certification test fuel which is an 

oxygenated fuel for exhaust emission testing with an appropriate adjustment factor for the 

emission results reported. OPEI’s engine manufacturers recommended that a standard 

adjustment factor for 50 state correlation (CARB/EPA) be included in the final regulation. EMA 

added that the emission adjustment factors should be defined either in the regulatory text or in 

guidance such that all manufacturers can utilize the same approved adjustments. 

With regard to handheld engines, OPEI also supported alignment of EPA certification 

fuel with the California certification fuel because the type of fuel may directly influence the 

results of any testing and the ability of manufacturers to confirm that technologies evaluated are 

in fact compliant with the proposed regulations. However, the means to achieve this alignment 

needs to be flexible. OPEI proposed allowing the use of CARB certification fuel for handheld 

engine exhaust emission testing without the need for correlation factors. OPEI requested that 

different approaches to the solution should be considered for 2-stroke and 4-stroke engines since 

the emissions are different. 

OPEI commented that EPA should harmonize the fuel for exhaust and evaporative 

emission testing because the same fuel can represent real world conditions in the field. EPA 

should accept a ten percent ethanol blend fuel as the standard test fuel for engines without 

changing the limits. If a manufacturer certifies with the ten percent ethanol blend fuel, OPEI 

commented that EPA should use the same fuel for any SEA or in-use testing conducted. 

Letters: 

Commenter Document # 

OPEI 0675 

Briggs and Stratton 0657 

EMA 0691 

Our Response: 

We are requiring Phase 3 exhaust emission testing with a standard test fuel consistent 

with the existing requirements under 40 CFR part 90 (see 40 CFR part 1065, subpart H). The 

existing regulatory specifications allow for no oxygenates in the test fuel. Because CARB 

specifies a test fuel which contains the oxygenate MTBE (but also allows for the use of EPA’s 

test fuel), we understand that some engine manufacturers will have emissions data from engines 

which meet EPA’s Phase 3 standards based on testing to meet California’s Tier 3 Small OffRoad Engine requirements for 2007 and later model years. In some cases this test data will be 

based on California’s oxygenated test fuel, although manufacturers have the option to certify 

using a test fuel such as that specified by EPA in 40 CFR Part 90. To allow for a quicker 

transition to the new EPA standards, we will allow for use of this pre-existing exhaust emission 

test data (based on California’s oxygenated test fuel) for EPA certification purposes through the 

2012 model year (see §1054.145(k)). Manufacturers could also use the CARB test fuel for their 

PLT testing, if they based their certification on that fuel. The use of the CARB data would be 

subject to the provisions for carryover data for demonstrating compliance with the standards in 

effect. (The carryover provisions for Phase 3 are specified in §1054.235(d) of the regulations.) 

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While we will allow use of this CARB data for certification through the 2012 model year, we 

will use our test fuel without oxygenates for all confirmatory testing we perform for exhaust 

emissions. We are limiting the timeframe for such a provision because we ultimately want the 

exhaust emission test results to be on the EPA specified test fuel. 

After the 2012 model year, a manufacturer wanting to use the CARB test fuel for 

certification purposes could request use of the CARB test fuel under the provisions of 40 CFR 

1065.701(b) which apply for alternate fuel specifications. As part of that request, the 

manufacturer is required to show that use of the alternate test fuel will not affect the ability to 

demonstrate compliance with all applicable emission standards. We would expect this showing 

should be straightforward for handheld engines, where we are not changing the exhaust emission 

standards for Phase 3 and where many manufacturers are already using CARB test fuel and 

should already be taking any emissions difference into account when certifying their engines. 

For nonhandheld engines, where we are changing the exhaust standards for Phase 3, we would 

expect to see emissions data showing the impact of the alternate fuel on emissions (compared to 

EPA’s standard test fuel) as part of the manufacturer’s request to use an alternate fuel under 40 

CFR 1065.701(b). While we may allow use of alternate test fuels such as the CARB test fuel 

after the 2012 model year, we will use our test fuel without oxygenates for all confirmatory 

testing we perform for exhaust emissions. Furthermore, because of the differences in engine 

technologies, we do not believe it is appropriate for us to establish an “adjustment factor” for 

CARB certification fuel or any other potential alternate fuel. Each manufacturer would need to 

determine the emissions impact of the alternate fuel for its specific engine designs. 

In the proposal we noted our concerns about testing with oxygenated fuels since this 

could affect an engine’s air-fuel ratio, which in turn could affect the engine’s combustion and 

emission characteristics. Because of the relatively recent dramatic increase in the use of ethanol 

(another oxygenate) in the broad motor gasoline pool, we have reexamined our position (as 

discussed below) and are adopting provisions that will allow manufacturers to use a 10 percent 

ethanol blend for certification testing for exhaust emissions from nonhandheld engines, as an 

alternative to the standard test fuel. This option to use a 10 percent ethanol blend will begin with 

the implementation date of the Phase 3 exhaust standards. The option would apply to 

production-line testing as well if the manufacturer based their certification on the 10 percent 

ethanol blend. We are also committing to using a 10 percent ethanol blend for all confirmatory 

testing we perform for exhaust emissions under the provisions described below. 

Ethanol has been blended into in-use gasoline for many years, and until as recently as 

2005, was used in less than one-third of the national gasoline pool. However, ethanol use has 

been increasing in recent years and, under provisions of the Energy Independence and Security 

Act of 2007, ethanol will be required in significantly greater quantities. We project that 

potentially 80 percent of the national gasoline pool will contain ethanol by 2010, making ethanol 

blends up to 10 percent the de facto in-use fuel. As ethanol blends become the primary in-use 

fuel, we believe it makes sense for manufacturers to optimize their engine designs with regard to 

emissions, performance, and durability on such a fuel. We also believe manufacturers need to 

know that any confirmatory testing we do on their engines will be performed on the same fuel 

the manufacturer used for certification since the fuel can impact the ability to demonstrate 

compliance with the emission standards. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Limited data of nonhandheld engine emissions tested on 10 percent ethanol blends 

suggests the HC emissions will decrease and NOx emissions will increase compared to 

emissions from the same engine operated on current certification fuel without oxygenates. 

Depending on the relative HC and NOx levels of the engines, these offsetting effects can result 

in small increases or decreases in total HC+NOx emission levels. Because the impact on 

HC+NOx emissions can vary slightly from engine family to engine family, we do not want 

manufacturers varying their certification fuel from one family to another to gain advantage with 

regard to emissions certification. 

Therefore, if a manufacturer wishes to use a 10 percent ethanol blend for certification, we 

are adopting provisions that require manufacturers to use the 10 percent ethanol blend for all of 

their Phase 3 nonhandheld engines for a given engine class within three years of the Phase 3 

standard taking effect (i.e., by the 2014 model year for Class I engines and by the 2013 model 

year for Class II engines). During the transition period, we will perform any confirmatory 

testing on the 10 percent ethanol blend if that is the fuel used by the manufacturer for 

certification. At the end of the transition period, we will perform any confirmatory testing on the 

10 percent ethanol blend if that is the fuel used by the manufacturer for certification, but only if 

the manufacturer has certified all of their nonhandheld engines in that engine class on the 10 

percent ethanol blend. If the manufacturer has not certified all of its engines in a given engine 

class on the 10 percent ethanol blend, we could decide to test the engine on our current test fuel 

without oxygenates. 

For handheld engines, where we do not have sufficient data on the impact of ethanol 

blends on emissions, we are adopting a slightly different approach. Manufacturers will have the 

option to use a 10 percent ethanol blend for certification beginning with the 2010 model year. 

The option to use a 10 percent ethanol blend would apply to PLT testing as well if the 

manufacturer based their certification on the 10 percent ethanol blend. While we will allow use 

of a 10 percent ethanol blend for certification, we expect to use our test fuel without oxygenates 

for all confirmatory testing for exhaust emissions. Therefore, an engine manufacturer will want 

to consider the impacts of ethanol on emissions in evaluating the compliance margin for the 

standard, or in setting the FEL for the engine family if it is participating in the ABT program. 

We could decide at our own discretion to do exhaust emissions testing using a 10 percent ethanol 

blend if the manufacturer certified on that fuel. It can be noted that both EPA and CARB are 

currently running test programs to look at the emission impacts of a 10 percent ethanol blend on 

a range of small SI engines, including handheld engines. Based on the results of that test 

program, we may want to consider changes to the provisions allowing the use of a 10 percent 

ethanol blend for certification and PLT testing for handheld engines. If the results of the 

handheld engine testing show that emissions are comparable on both fuels, we would expect to 

revise the provisions for handheld engines and adopt similar requirements to those adopted for 

nonhandheld engines as noted above. 

The test fuel specifications for the 10 percent ethanol blend are based on using the current 

gasoline test fuel and adding fuel-grade ethanol until the blended fuel contains 10 percent ethanol 

by volume. It should be noted that this is the first time EPA regulations specify the use of an 

ethanol test fuel for exhaust emissions testing for certification purposes. It is likely that EPA 

will consider similar test fuel changes in the future for other vehicle and engine categories 

including those addressed in this final rule. As part of those deliberations, it is possible that EPA 

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could decide that the test fuel specifications for the ethanol blend should be different than those 

adopted in this rule. Should that occur, EPA would need to consider whether changes to the test 

fuel specifications adopted in this rule for the 10 percent ethanol blend are appropriate for 

nonhandheld engine testing. 

2.5.5 1065 Issues for Small SI Engines 

Comments were received from industry and industry organizations on several issues 

relating to the application of Part 1065 to Small SI engines. This section describes issues that are 

specific to Small SI engines. See Section 1.4 for more general issues raised by commenters 

related to engine testing under Part 1065. 

What Commenters Said: 

In the proposal and in its administrative record, EPA has not clearly identified, much less 

evaluated, all the potential impacts that could occur by replacing the Part 90 exhaust emission 

test procedures for small-spark-ignited engines with the generic Part 1065 exhaust emission test 

procedures. The 1065 test procedures were developed for very different types of much larger 

and more sophisticated engines. OPEI stated that its members are committed to working with 

EPA to fill the critical data gaps. However, there is no way EPA or industry could generate all 

the needed information in the next few months, complete this evaluation, and make all the 

needed improvements – before the final Phase 3 rulemaking must be issued. For these reasons 

(which are discussed in more detail below), EPA should allow (on a permanent basis) small 

engine exhaust testing at facilities that use equipment and procedures that are compliant with the 

existing Part 90 equipment, procedures and calculations. 

1. Equation Calculations: Kohler, B&S and OPEI stated that Part 1065 should not be 

implemented until correlation between Part 90 and Part 1065 (subsection G) calculations 

have been adequately demonstrated (documented, correlates and validates). Before 

eliminating or making any changes to the well-established Part 90 test procedures, EPA 

should first conduct comparative testing, and identify and analyze all the impacts of 

shifting to Part 1065. Industry has developed a database of information with part 90 over 

the past 10 years. The proposed changes to calculate emissions on Part 1065 are 

confusing and jumbled. Simple spreadsheet calculation methods are now impossible and 

a program dedicated to an iterative solution is required. There is no data in the record to 

show the proposed test method would yield the same results. If the correlations are not 

completed, the manufacturers of Small SI engines must be allowed to continue to use the 

40 CFR Part 90 calculation methods. 

Specifically, OPEI stated that virtually all small SI engines operate richer than 

stoichiometry and the majority of testing is conducted using raw gas sampling methods. 

Consequently, the applicability of the equations for raw gas emission measurement for 

engines with air/fuel ratios richer than stoichiometric are critical. Part 1065 prescribes 

equations associated with the conversion of the raw analyzer measurements to the mass 

equivalent. Much more measured data (like H2O, N2O, aldehydes) would be needed to 

prove the equivalence of the 1065 calculation on a theoretical (mass balance of O, C, N, 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

H) and practical bases. Differences in exhaust sampling systems may affect these 

chemical reactions/equilibrium and thereby the exhaust gas composition and measured 

values. It is a well known effect that hydrocarbons are converted to CO at high 

temperatures (post catalyst). Probes, sampling location, temperatures and flow rates all 

have a potential effect to change the measured values within a raw gas measurement. 

2. Test fuels: In addition, the test fuel specifications in Part 1065 are different than existing 

Part 90 fuel specifications which could also result in skewed, different reported 

emissions. Part 1065 does not include any specification that addresses the 2-stroke oilgrade and mixing ratio. (See 40 CFR S. 90.308). (OPEI) 

Test methods: Before eliminating Part 90 as an option for test equipment, EPA would 

first need to resolve numerous outstanding issues, make needed modifications, and 

document that Part 1065 requirements can be practically implemented with small 

engines. 

3. Fuel flow meter issues: a) the accuracy prescribed by §1065.205 may be impossible to 

meet for small engine test cells. Current known instruments will nominally meet the 2% 

accuracy and 1% repeatability values specified in Part 90, but may not meet the 

percentage of maximum or the percentage of point requirements specified in Table 1 of 

1065.205. b) Linearity verification for fuel flow rates ≤1% (under §1065.307) are not 

feasible for small engines with low fuel flow rates. c) Lastly, a concern expressed was 

that the wide open fuel flows of today’s Part 1065 engines may reach as much as 50 

liter/hour whereas Small SI engines frequently do not exceed 0.5 liters/hour. (Industyr 

representatives later indicated that these points were meant to raise the issue that the 

tolerances in these sections are not yet known to be achievable.) 

4. The requirement to control torque as needed to meet 40 CFR Part 1065.514 cyclevalidation criteria may not be feasible for test modes with very low target set points. 

Currently, 40 CFR Part 90.410 includes a provision for Phase II testing that reads as 

follows: "hold the specified load within the larger range provided by ±0.27 Nm (±0.2 lbft), or ±ten (10) percent of point" for current Phase 2 engine testing. EPA must include a 

similar provision applicable to the testing of engines with modes where torque set points 

result in impractical cycle validation, as prescribed by §1065.514. (EMA) The comments 

also stated a concern that the torque transducers called for in Part 1065 today would 

measure up to hundreds of joules of torque whereas the transducer used for engines 

specified in Part 90 measure in the range of tenths of joules. The characteristic of these 

engines requires a transducer to handle high torque spikes yet, measure smaller torque 

ranges once the engine stabilizes. (OPEI) 

5. Part 1065 analyzers which are designed for larger engine emission measurements might 

not be practical or suitable for long-term emission measurements on small SI engines – at 

least without substantial modifications. For example, the HC hang-up specifications (2 

ppm) in S. 1065.520 are impractical for the much higher HC emission concentrations 

measured on rich burn gasoline sampling raw gas concentrations. 

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Chapter 2: Small SI Engines 

6. The ambient conditions defined by 40 CFR Part 1065.520 are different than the 

conditions prescribed by §1054.115(c). Specifically, the ambient pressure range 

specified in §1065.520 is a range from 80.0-103.325 kPa; and the pressure range 

specified in §1054.115(c) is 94.0-103.325 kPa. The Part 1065 ambient condition 

requirements should be clarified in order to provide that the general requirements 

prescribed in Part 1065 are pre-empted by the standard setting Part. (EMA) 

7. The NPRM does not allow exhaust emission test results to be adjusted in order to account 

for the effect of ambient humidity. However, NOx emissions test data is currently 

corrected for humidity pursuant to 40 CFR Part 90.419. Because many laboratories do 

not have the ability to run at controlled humidity (as EPA can), such corrections are often 

significant. The final regulation must allow the correction of emission test results for 

humidity as currently prescribed by § 90.419 (and utilized by CARB). (EMA) 

OTHER: 

8. Based on the limited information that EPA has provided, it is difficult for OPEI to 

comment on all the ramifications of this proposed change. However, it appears that the 

Part 1065 test procedures could cause small engine manufacturers to spend hundreds of 

thousands of dollars on at least new calibrations and software with no environmental 

benefits. The cost estimate of equipment upgrades will be as much as $500,000 per test 

cell with no real benefit to emissions. (OPEI) 

9. EPA has also not identified how a shift to the Part 1065 test procedures would impact 

small engine manufacturers in terms of replacing or modifying their existing Part 90-

compliant test equipment and related software and calibrations. 

10. Manufacturers noted that some manufacturers control engines at idle by setting the 

dynamometer to control engine speed and use operator demand to control torque (usually 

zero, but not always), while other manufacturers take the opposite approach. 

11. Given numerous uncertainties, the application of Part 1065 could result in more stringent 

exhaust standards. At least for handheld manufacturers, the Part 1065 test procedures 

could also unintentionally result in more stringent exhaust standards. To avoid these 

unintended consequences, EPA should allow small engine manufacturers to continue to 

rely on the Part 90 test procedures, which could simply be referenced in the new Part 

1065. (OPEI) In its Phase 3 proposal, EPA repeatedly indicated it would not change the 

stringency of the Phase 2, exhaust standards for Handheld (HH) products. The Phase II 

exhaust standards for HH engines are exclusively based on data generated from Part 90 

test equipment. EPA's proposal and supporting administrative record do not evaluate 

whether, or to what extent, the application of the Part 1065 requirements and calculations 

could generate higher reported emissions from small engines (compared to Part 90) – 

unintentionally resulting in more stringent standards than are supported by EPA's record. 

12. The requirement to submit a written report explaining reasons for invalidating any test 

and the need for EPA to authorize retesting is overly broad and requires clarification. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

There is no need for EPA to authorize common causes for clearly invalid tests, such as 

invalid pre- or post- span measurements, etc. The requirement to submit the test result 

from an invalid test is acceptable provided EPA recognizes that in some cases the reason 

that the test is invalid will result in erroneous results that should not be used for any 

purpose. (EMA) 

13. OPEI stated some members have recently purchased Part 1065-compliant analyzers and 

equipment in other industry segments based on their reliance on EPA’s proposal that they 

would be able (as an option) to start certifying products with this equipment immediately. 

OPEI supports EPA’s proposed approach to allow (as an option) certification testing 

using Part 1065-compliant equipment. 

14. TIMING: At this stage in the rulemaking, there is inadequate time and resources for 

EPA and the affected stakeholders (including test equipment suppliers) to gather the 

needed information and then to develop proposed tailored solutions and regulatory 

modification to address all the unresolved issues. There is no way EPA could issue a 

final regulation in June 2008 that would address all these problems with the needed 

modifications for small engines. 

15. Part 1065 Test Procedures would Create Discriminatory Trade Barriers 

The U.S. EPA proposed test equipment changes would contradict the agreed-to goals of 

standards-harmonization and, in certain circumstances, could create a barrier to trade. 

CARB and the EU emissions regulations for small engines are based on the Part 90 

procedures. As indicated in CARB comments into EPA's Phase III rulemaking, CARB 

may not accept certification data from Part 1065 test equipment for small engines. 

CARB remains concerned that Part 1065 equipment will not generate the same results as 

Part 90 test equipment for small engines. In a call on January 23, 2008, CARB's 

certification office confirmed that CARB will not generically accept certification test data 

on small engines based on Part 1065 test results because of the absence of any existing 

database that generically documents the equivalency of Part 1065 and Part 90 test 

procedures as applied to small engines. Consequently, CARB will require individual 

manufacturers to demonstrate complete and identical test equivalency on their proposed 

test equipment through a comprehensive CARB-approved test plan. To our knowledge, 

no small engine manufacturer has made such a demonstration to CARB's satisfaction. 

We expect other jurisdictions, including the EU, to adopt a similar position and refuse to 

accept Part 1065 test results for small engine certification in the absence of a 

comprehensive demonstration of equivalency. Such demonstrations will be very difficult 

to prove. Even after expending substantial resources to try and establish such an 

equivalency, it is uncertain whether individual manufacturers' test equipment will meet 

CARB's and the EU's requirements. 

Other major countries, including China, are developing regulations that are primarily 

based on the EU regulations and the related Part 90 testing procedures. EPA's proposed, 

unilateral changes to these test procedures would force at least European and Asian small 

engine manufacturers (that need to produce uniform products for the global market) to 

spend millions of dollars to purchase, install and calibrate separate analyzers, software, 

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Chapter 2: Small SI Engines 

and instrumentation (and invest in additional personnel) to re-test dozens of different, 

emission-compliant, engine families that are exported to the U.S. market. 

A disproportionate cost burden would be born by smaller and mid-size European and 

Asian manufacturers that typically manufacture and certify small volume or “niche” 

products for the U.S. market. In fact, the higher per-unit costs of U.S. EPA certificationtesting could bar small volume European and Asian producers from being able to 

compete and sell niche products in the U.S. market. For example, smaller manufacturers 

with only a few test cells would likely incur at least $300,000 in additional costs in 

modifying their test cells in order to test and certify (with EPA) their US products under 

the Part 1065 procedures. Assuming a 5-year amortization, this would result (on 

average) in $73,000 in additional testing costs per year. Many of the affected niche 

product lines produced by European and Asian manufacturers consist of only 1,000 units 

in U.S. sales each year. For such products, European and Asian manufacturers would 

incur additional, amortized testing costs in the range of $73 per unit for niche lawn and 

garden product lines that typically sell for less than $300 per unit. Thus, the U.S. EPA’s 

proposed “Part 1065” test procedures could create discriminatory trade barriers that 

unfairly discriminate against the niche products and low-volume manufacturers and 

would require them to invest in expensive and redundant emission test equipment. 

Euromot also stated that the changes in the test procedures as proposed by introducing 

§1065 would generate a misalignment with present equipment and worldwide 

harmonized procedures and would not generate additional value to the US customers. 

Euromot therefore asks EPA to stay with the current part 90 test procedures. 

On March 19, 2008 Euromot sent a followup letter to their comments on the NPRM and 

stated that in the final Phase 3 rule, EPA should 1) continue to apply harmonized Part 90 

Test procedures to small spark-ignited engines; and 2) Commit to initiate a process to 

develop Global Technical Regulation (GTR) with the coordinated participation of the EU 

and other international stakeholders (including Euromot) to develop new test procedures 

that are specifically tailored to the unique challenges of small spark ignition engines. 

Stihl further emphasized their interest in cooperating with EPA in an effort to develop a 

Global Technical Regulation. They noted that Euromot’s goal is a very precise test 

method that does not give flexibility towards "creative" test results, rather than leaving 

specifications that are too general to serve as a practical instruction for companies that 

may be inclined to cut corners in their testing efforts. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

OPEI 0675 

OPEI 0752 

Euromot 0649 

Euromot 0766 

Kohler 0703 

Briggs and Stratton 0657 

EMA 0691 

Stihl 0784 

Our Responses: 

Before addressing the specific comments, it is important to note that since the time of the NPRM, 

we have made changes to part 1065 in a separate rulemaking that also set new emission 

standards for locomotives and marine diesel engines (73 FR 37096, June 30, 2008). As 

described below, several of these changes address comments that we received on this rule. 

1. Equation Calculations – correlation needed, else allow manufacturers to use Part 90. 

Industry commented that correlation between Part 90 and Part 1065 calculations has not 

adequately been demonstrated for these classes of engines. EMA, B&S, OPEI, Kohler stated 

part 1065 not be implemented until it is shown 1065 and 90 are equivalent for raw gas 

measurements. 

In response to comments, we have conducted a thorough comparison of the part 90 and part 1065 

calculations.1

 Our initial analysis show small but significant differences between the two 

methods. Some of the initial differences are being eliminated through changes to the part 1065 

equations as described below. Others that are the result of errors in the part 90 calculations are 

not being eliminated. Calculations from the modified part 1065 equations and from the part 90 

equations for handheld engines are presented below. The table below shows the differences 

between the Part 90 and Part 1065 data sets with Part 1065 calculations yielding lower emission 

results for HC and overall HC+NOx. Existing data can be recalculated or adjusted to be 

comparable to part 1065 results. 

1

 In January/February of 2008, EPA shared correlated data with the nonhandheld and handheld industries based on 

industry submitted data. 

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Chapter 2: Small SI Engines 

Percent difference between emissions calculated using part 90 versus part 1065 equations 

(Negative values indicate that values calculated according to 1065 are lower than those calculated 

according to 90.) 

HH HH NHH NHH 

Raw* CVS Test 1 Test 2** 

HC -2.51% -2.78% -2.19% -2.28% 

NOx 0.29% -0.13% 0.41% 0.32% 

CO 0.23% 0.28% 0.22% 0.21% 

* Errors were found in the currently published Part 90 calculations and are being corrected with this final 

rulemaking. 

** An error was found in the industry Kh calculation related to nonhandheld engines for Test #2; it was 

corrected and comparison to 1065 was based on the corrected numbers. 

As part of the exercise to compare calculated emission results, we determined that it was 

necessary to account for free hydrogen in the exhaust as part of the carbon balance. This is 

particularly important for engines that run rich of stoichiometry because of the greater 

concentration of hydrogen formation with such engines. For engines that have already been 

subject to testing under Part 1065 using the old equations, calculating based on a zero 

concentration of hydrogen in the exhaust is a reasonable simplifying assumption. We have 

modified the Part 1065 equations in this rule to reflect the need to account for hydrogen in the 

exhaust for engines that run rich of stoichiometry. The hydrogen values can be calculated and 

need not be measured by an analyzer. 

2. Specifications for 2-stroke oil grade and mixing ratio will be considered. Specifications 

for test fuels will be evaluated and considered. 

In response to comments, EPA is adding 2-stroke oil grade and mixing ratio specification to 

part 1065 in subpart H. The new language is being taken from §90.308(a)(1), which states that 

the fuel/oil mixture ratio must be that which is recommended by the manufacturer for the 2-

stroke engines. 

3. Fuel flow meter issues 

Regarding measurement of fuel flow rates, the equipment for measuring fuel flow rates 

so precisely may not currently be in use by all in industry. Currently part 90 states that test 

points are to come within, 2% at non-idle and 5% at idle of the reading. According to the 1065 

requirements for the calibration of the fuel flow meter, the engine manufacturers must test 10 

points over the range of fuel measurement expected during the entire test. The verification tests 

then apply to this linear line and calibrations of the system are to be done. For a handheld engine 

the certification test uses only two test points during its test and may use 0-6lb/hr for example. 

The two modes are at WOT and idle and therefore the in between points are never used. For a 

nonhandheld engine that used 0-3 lb/hr, a reading must be taken every 0.33 lb/hr and there are 6 

modes in the certification test. Industry does not yet know if fuel flow measurement equipment 

is available to read to this degree and does not see the need for this precision for neither of these 

test procedures are transient. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

EPA would like to ensure linearity of the fuel flow meter within the range of testing. 

This cannot be a simple two point verification, but needs to include enough points to insure 

linearity between the maximum and minimum fuel flow rates. This check only needs to be 

performed yearly; therefore EPA would like the small handheld engine manufacturers to perform 

the fuel flow meter linearity verification check as currently described in 1065.307. 

One possible solution is to use gravimetric technology as long as the linearity 

specifications in 1065 are met. 

Table 1: Comparison of Requirements for Fuel Flows 

Fuel Flows Part 90 Part 1065 

Fuel flow meter 

specs 

90.328: Measurement equipment 

accuracy/calibration frequency table. 

Table 2: Permissible deviation from 

reading: fuel consumption: +/-2% at 

non-idle 

+/-5% idle 

 (Recommendation) : 

Table 1 of 1065.205 

5 sec rise and fall time 

1Hz 

Accuracy: 2% of pt/1.5% of max 

Max repeatability: 1% pt/.75% max 

Noise .5% 

Linear 

Verification 

None... Linear verification 1065.307 

- 10 measurement points covering range of 

test meas. 

- least squares linear regression and the 

linearity criteria specified in Table 1 of this 

section. 

Calibration and 

verify

 1065.320 

Frequency of 

Calibration 

Calibrate monthly or within one month 

prior to the certification test. 

Measurement systems that require linearity 

verifications ... 

Torque and Fuel Flow: 

Within 370 days before testing 

4. Torque related issues 

As industry works with 1065 over the coming years, we expect to work with industry to 

understand how to properly measure torque. In particular, we believe it is possible to use 

equipment meeting the torque requirements for testing Small SI engines, even at the low torque 

levels that are typical for these engines. We have modified the cycle-validation criteria for 

torque as described in Section 2.5.7 to more carefully reflect the level of precision that is 

appropriate for Small SI engines. 

EPA would like to ensure linearity of the torque meter within the range of testing. This 

cannot be a simple two point verification, but needs to include enough points to insure linearity 

between the maximum and minimum torque values. This check only needs to be performed 

yearly; therefore EPA would like the small handheld engine manufacturers to perform the torque 

meter linearity verification check as currently described in §1065.307. 

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Chapter 2: Small SI Engines 

Table 2: Comparison of Requirements for Torque Transducers 

Torque 

Transducers 

Part 90 Part 1065 

Calibration 

procedures 

90.305 Dynamometer 

specifications and calibration 

accuracy 

... a minimum of three 

calibration weights for each 

range used is required. The 

weights must be equally spaced 

and traceable to within .5% of 

NIST weights. (foreign 

countries.. use wtd to local gov 

stds) 

90.306 Dynamometer torque cell 

calibration 

Gives details on procedure 

§1065.307 Linearity verification. 

(2) Engine torque. Use a series of calibration weights 

and a calibration lever arm to simulate engine torque. 

You may instead use the engine or dynamometer 

itself to generate a nominal torque that is measured 

by a reference load cell or proving ring in series with 

the torque-measurement system. In this case use the 

reference load cell measurement as the reference 

value. Refer to §1065.310 for a torque-calibration 

procedure similar to the linearity verification in this 

section. 

1065.310: ... Apply at least six calibration-weight 

combinations for each applicable 

torque-measuring range, spacing the weight 

quantities about equally over the range. 

Calibration 

accuracy 

90.306 dynamometer torque cell 

calibration 

Meas torque must be within 2% 

of calculated torque 

Table 1 of §1065.307–Measurement systems that 

require linearity verifications.. 

specifications given for linearity 

Calibration 

frequency 

90.328 Measurement equipment 

accuracy/calibration frequency 

table. 

Torque: monthly or within one 

month prior to the certification 

test 

Table 1 of §1065.307– 

Linearity for system (fuel flow rate and engine 

torque) – every 370 days 

1065.310 Torque calibration. 

Calibrate all torque-measurement systems including 

dynamometer torque measurement transducers and 

systems upon initial installation and 

after major maintenance. Use good engineering 

judgment to repeat the calibration. 

5....The HC hang-up specifications (2 ppm) in S. 1065.520 are impractical for the much higher 

HC emission concentrations measured on rich burn gasoline sampling raw gas concentrations. 

This language was changed in the locomotive/marine 2008 final rulemaking to address 

this concern. 

6. The Part 1065 ambient condition requirements should be clarified in order to provide that the 

general requirements prescribed in Part 1065 are pre-empted by the standard setting Part. 

(EMA) 

Section 1065.5 states “The testing specifications in the standard-setting part may differ 

from the specifications in this part. In cases where it is not possible to comply with both the 

standard-setting part and this part, you must comply with the specifications in the standard 

setting part. The standard-setting part may also allow you to deviate from the procedures of this 

part for other reasons.” Thus the regulations are already clear in this respect. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

7. EPA needs to allow for correction of ambient humidity 90.419 (also used by CARB). Industry 

does not have humidity controlled test cells. 

Parts 1045 and 1054 are being revised to allow the correction of NOx for humidity. 

Equation 1065.670-1 calculates the correction. The 2006 version of Part 90 also refers to the 

same equation so there is no change in this calculation. 

8. Based on the limited information that EPA has provided, it is difficult for OPEI to comment on 

all the ramifications of this proposed change. However, it appears that the Part 1065 test 

procedures could cause small engine manufacturers to spend hundreds of thousands of dollars 

on at least new calibrations and software with no environmental benefits. The cost estimate of 

equipment upgrades will be as much as $500,000 per test cell with no real benefit to emissions. 

(OPEI) 

We disagree with the estimated cost and the supposition that upgrading to part 1065 will 

have no benefits. As described in the RIA, we believe that a typical manufacturer will need to 

spend much less than this to upgrade its test facilities to be part 1065 compliant. To the extent 

that any manufacturer needs to spend more, it will be because they are currently using outdated 

equipment that is not sufficiently accurate, precise, and/or reliable to demonstrate compliance 

with EPA standards. Clearly having more accurate and repeatable measurements is beneficial. 

9. EPA has not identified how a shift to the Part 1065 test procedures would impact small 

engine manufacturers in terms of replacing or modifying their existing Part 90-compliant test 

equipment and related software and calibrations. 

Industry does not have to certify with part 1065 procedures until 2013 and therefore time 

is available to meet with EPA on specific questions related to part 1065 compliance. With 

proper planning, industry can plan out any changes over time. 

10. Testing at idle 

We agree that manufacturers should be able to choose whether to use the dynamometer or 

operator demand to control speed and torque during idle operation. We understand that in some 

cases, once the engine is stable and the dynamometer controls are functioning, engines may be 

tested in a configuration such that the engine operates at the specified speed or torque level 

without adjustment. 

11. Part 1065 could result in more stringent exhaust standards 

The nonhandheld industry provided EPA with emission test data from two engine tests 

using raw emission measurement. The handheld industry provided EPA with one raw emission 

dataset and one CVS emission dataset. EPA verified industry’s Part 90 calculations and then 

used the data to calculate results using 1065 calculations. In each case, the numbers correlated 

between Part 1065 and Part 90 within -2.3% of HC on nonhandheld test data and -2.78% HC on 

the handheld raw test data. In each case the 1065 calculations yielded lower numbers for the 

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Chapter 2: Small SI Engines 

pollutant of THC due to the use of Part 1065’s molecular weight of hydrocarbon default number 

rather than calculating it as was done in Part 90. The slight percentage decrease in effect yields 

slightly more lenient exhaust standards for the four datasets used in this analysis. Changes of up 

to 0.41% for NOx and 0.21 to 0.28% for CO are slightly more stringent standards for these 

pollutants in these examples. 

The changes of <0.41% for NOx and <0.28% for CO on handheld and nonhandheld engines are 

very small changes. The NOx levels are very small on hh engines (test data showed 0.4%-0.8% 

of HC+NOx is NOx) and the emission standard for HC+NOx is either 50 g/kWhr or 72 g/kWhr, 

for Classes III, IV and Class V respectively. Therefore there is only a very slight increase in 

stringency in the standard. The handheld industry test results showed CO between 400 and 500 

g/kWhr on the two sets of data for handheld engines. A 0.28% difference would mean an 

addition of approximately 1.12-1.4 g/kWhr. For nonhandheld engines, the overall change in 

HC+NOx was -1.7% and -1.6% for the two tests with the decrease in HC and the increase in 

NOx combined. For CO, test data shows the nonhandheld engines at 374 and 390 g/kWhr and 

0.28% of these values are 1.05 and 1.09 respectively. This again is only a very slight increase. 

12. The requirement to submit a written report explaining reasons for invalidating any test and 

the need for EPA to authorize retesting is overly broad and requires clarification. There is no 

need for EPA to authorize common causes for clearly invalid tests, such as invalid pre- or postspan measurements, etc. The requirement to submit the test result from an invalid test is 

acceptable provided EPA recognizes that in some cases the reason that the test is invalid will 

result in erroneous results that should not be used for any purpose.(EMA) 

We agree that preapproval to retest after an invalid test is not necessary in most cases. 

However, it is necessary for invalid test results to be reported along with an explanation of why a 

test was invalidated. The revised regulations are also clear that we reserve the right to require 

preapproval of using retest results in PLT calculations should we determine that a manufacturer 

is inappropriately invalidating tests. 

13. OPEI supports EPA allowing immediate certification with part 1065 compliant equipment. 

Part 1065 allows for the early use of these procedures consistent with good engineering 

judgment. 

14. Inadequate time and resources for EPA and the affected stakeholders to gather needed 

information and present tailored solutions and regulatory modification to address all unresolved 

issues. 

The industry is not required to use part 1065 until 2013, which will allow over 4 years 

from the time of the final rule to modify the procedures. Also, the regulations in part 1065 

include numerous provisions to provide manufacturers to use equivalent procedures. Thus we do 

not anticipate any problems associated with the timing of this requirement. 

15. Part 1065 Test Procedures would Create Discriminatory Trade Barriers 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

In regards to the concern that CARB will not accept 1065 based certifications: CARB has 

been informed of Part 1065 along the way and will be adopting 1065 test procedures for small 

spark ignition engines. 

Regarding the European Union adoption of 1065 procedures for small SI engines: it is 

likely that industry will begin proceedings for a GTR for small SI engines which will address 

1065 requirements versus “may” options. The European community has already adopted 1065 

for diesel engines. 

Euromot stated that:“The changes in the test procedures as proposed by introducing §1065 

would generate a misalignment with present equipment and worldwide harmonized procedures 

and would not generate additional value to the US customers. We therefore ask EPA to stay with 

the current §90 test procedures.” 

EPA is moving to 1065 test procedures and is planning to take steps to work with the 

California Air Resources Board. EPA has also begun talks with industry representatives to 

discuss any issues related to testing small SI engines per part 1065. Part 90 is somewhat vague 

in several areas relating to emission testing procedure. Part 1065 provides guidance in those 

areas. 

Euromot requested that EPA commit to initiate a process to develop Global Technical 

Regulation (GTR) with the coordinated participation of the EU and other international 

stakeholders (including Euromot) to develop new test procedures that are specifically tailored to 

the unique challenges of small spark-ignited engines. 

EPA will continue to interact with manufacturers on issues that arise in complying with 

part 1065 as they work toward making any necessary changes to comply with the new test 

procedures starting with the 2013 model year. Given that the test procedures in part 1065 have 

been demonstrated to be complete and consistent with the existing procedures in part 90, EPA 

believes it is not necessary to initiate a Global Technical Regulation at this point. However, if 

there is an international or other forum for exploring testing issues for Small SI engines, EPA 

would expect to participate in that effort. 

2.5.6 Running loss simulation during exhaust test 

What Commenters Said: 

OPEI commented that the influence of running loss vapor on exhaust emissions is 

insignificant and should not be associated with the exhaust emission testing requirement. It is 

impractical for an engine manufacturer to exhaust emission test engines that are installed in a 

wide variety of equipment that include a wide variety of fuel tank sizes and running loss vapor 

generation characteristics. (EMA) The proposal’s requirement that running loss controls be 

included when conducting exhaust emission tests is not practical. Emission tests are conducted in 

engine emission dynamometer test cells that include fuel delivery systems and do not generally 

include engine mounted fuel delivery systems. A given engine family may be utilized with a 

large variety of fuel tank configurations, some of which will be supplied by the engine 

manufacturer and some of which will be supplied by OEM customers. In addition, the inclusion 

of the running loss control system may significantly compromise the ability to comply with the 

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Chapter 2: Small SI Engines 

requirements for running the exhaust emission test - i.e., measurement of fuel flow for raw gas 

testing. Accordingly, this requirement should be eliminated. 

EMA commented on §1054.501(b)(6) “How do I run a valid emission test?” This 

requirement is not practical for emission testing. Exhaust emission tests are conducted in engine 

emission dynamometer test cells that include fuel delivery systems and do not typically include 

engine mounted fuel delivery systems. A given engine family may be utilized with a large 

variety of fuel tank configurations, some of which will be supplied by the engine manufacturer 

and some of which will be supplied by OEM customers. Accordingly, this section should only 

include the first sentence, and the remainder of the section should be deleted. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

As described in Chapter 5 of the Regulatory Impact Analysis, we measured in-use fuel 

temperatures and corresponding emission rates to quantify running loss emissions from various 

types of equipment. In some cases, measured temperature increases and emission rates were 

small. However, we noted that some equipment had fuel tanks positioned closer to the engine or 

other heat sources such that they experienced significant fuel heating. One case involved a 24°C 

temperature rise, which corresponded to a 69.3 g/hour emission rate. Total fuel consumption for 

a Class I engine might be about 300 g/hour (220 g/kW-hr with a 3 kW engine operating at 50 

percent load). In this case, the engine would be ingesting 25 percent more fuel than it was 

designed for. The engine’s emission controls would clearly not be able to compensate for this 

unmetered vapor load. Class II engines have higher fuel flow rates, but a similar assessment 

shows that a 12 kW engine would be ingesting about 6 percent more fuel than it was designed 

for. Even this smaller deviation would likely cause an engine without feedback controls to 

exceed emission standards. 

Measuring emissions from an engine for which the onboard fuel tank supplies the fuel, 

including any running loss vapors routed to the intake, is not difficult with dilute-sampling 

equipment. We understand that this is much more difficult with raw sampling, and that 

individual labs may have some safety-related or other restrictions that make it impractical to do 

this testing. As a result, we are keeping the specification to include ingestion of actual or 

simulated running-loss vapors in the engine’s intake during exhaust testing, but we are adding an 

allowance for manufacturers to make an engineering evaluation to show that actual vapor loads 

from in-use engines will not cause the engine to exceed the emission standard (or FEL if 

applicable). This would preserve the motivation for engine and equipment manufacturers to 

minimize the heat load on fuel tanks and to account for any remaining effect in establishing their 

compliance margins. We would expect any EPA measurement of exhaust emissions to include 

running-loss vapor loads (representative of in-use operation) as much as possible. For enginemounted tanks, we would expect to simply duplicate (or retain) this configuration for laboratory 

2-88 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

operation. For remote-mounted tanks, we may measure fuel temperatures from in-use equipment 

to properly simulate the running-loss effects. 

In cases where the engine manufacturer also designs the configuration and placement of 

the fuel tank, this exercise should be straightforward. We understand, however, that equipment 

designs may include a wide variety of configurations that are not all within the engine 

manufacturer’s control. In these cases, we would expect engine manufacturers to do 

development testing with their engines to be able to understand the sensitivity and limits of their 

engines’ compliance with exhaust emission standards as a function of running-loss vapor loads. 

For loose engine sales to equipment manufacturers that control fuel tank designs, we would 

expect engine manufacturers to specify in their installation instructions some appropriate limits 

on the extent of tank heating to prevent the engine from exceeding applicable emission 

standards. For example, engine manufacturers could directly specify a maximum vapor load (in 

grams per hour) for continuous operation in the final installation. The vapor load for a given 

operating condition would vary depending on the size of the tank. Engine manufacturers could 

therefore alternatively specify a table of values for maximum fuel-tank temperature rise for fuel 

tanks with a range of capacities. The specifications in these installation instructions would form 

the basis of the engine manufacturer’s simulation or analysis to demonstrate that the engine will 

meet emission standards in the final installation. Engine manufacturers may need to select a 

higher Family Emission Limit to include a sufficient compliance margin to take running-loss 

effects into account. 

2.5.7 Cycle-validation criteria 

What Commenters Said: 

EMA commented on §1065.514(f) Cycle-validation criteria. While statistical cycle 

validation makes sense for transient test methods, it is an unnecessary encumbrance to steadystate testing. The current method is to track minimum and maximum speeds and torques 

observed during the sampling period; test mode acceptance requires the extreme deviations from 

the desired set point to be less than a percentage of set point. If statistical steady state mode 

validation is required, the test control system will need to be revised, at considerable cost to the 

manufacturer with no resulting environmental benefit. Accordingly, statistical cycle validation 

should not be required for Small SI engines. 

EMA commented that the requirement to control torque as needed to meet §1065.514 is 

not feasible for test modes with very low target set points. Currently, pursuant to §90.410 the 

torque control requirement for Phase 2 engine testing is “hold the specified load within the larger 

range provided by ±0.27 Nm (±0.2 lb-ft), or ±ten (10) percent of point”. EMA commented that 

this section must include a similar provision for testing of engines where the required torque set 

points cannot use the cycle validation criteria required by §1065.514. 

EMA commented further on cycle-validation criteria: While the prescribed cyclevalidation criteria and statistical cycle validation is viable for transient test methods, it is an 

unnecessary encumbrance to steady state testing. Currently, engine manufacturers track the 

minimum and maximum speeds and torques observed during the sampling period, and the test 

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mode acceptance criteria require the extreme deviations from the desired set point to be less than 

a percentage of set point. No environmental benefit is achieved from the addition of statistical 

cycle validation criteria for steady-state testing, and it raises serious concerns for engine 

manufacturers. Accordingly, EMA recommends that these requirements be waived for Small SI 

engines. 

In response to a draft version of regulatory text suggesting updated cycle-validation 

criteria for nonhandheld engines, EMA suggested that the language should be in part 1054, not in 

part 1065, since it should apply specifically for Small SI engines. EMA further suggested that 

any change to what is required under §90.410 today would raise significant concerns. 

Letters: 

Commenter Document # 

EMA 0807 

EMA 0691 

Our Response: 

Specifying nominal test speeds and loads with no cycle-validation criteria is meaningless. 

Without some definition of acceptable deviation from the reference values, it would be 

impossible to invalidate a test no matter what speeds and loads the engine actually experienced. 

Manufacturers are testing with cycle-validation criteria today. These specifications provide a 

useful starting point for setting appropriate specifications. 

The current requirements in part 90 specify that torque for Modes 1 through 3 stay within 

5 percent of point. Torque for Modes 4 and 5 must stay within 0.27 Nm or within 10 percent of 

point, whichever is larger. This allows for very sloppy testing, especially for small engines. For 

an 85 cc engine with peak torque of 4.0 NM, the nominal torque setting for Modes 4 and 5 would 

be 1.0 and 0.4 Nm, respectively. Specifying these points as 0.4+0.27 Nm and 1.0+0.27 Nm 

means that any torque value between 0.13 and 1.27 Nm would be a valid test point except for the 

narrow range of 0.67 to 0.73 Nm. This effectively allows the manufacturer to pick the most 

favorable torque values for certification. Seen another way, this could be utilized for EPA 

testing as similar to not-to-exceed zones for specifying any test point around the nominal value. 

This is clearly not the intent of the specified parameters. 

We believe an alternative approach is better for targeting the nominal torque values for 

very small engines and will not increase the burden for running a valid test. Specifically, we 

believe there should be separate parameters to address a tolerance for the range of measured 

values and a limit for the mean value over the sampling period. Setting a tolerance specification 

of +2 percent of point or +0.27 Nm, whichever is greater is consistent with the part 90 

specifications, allowing for an achievable range of values for high-power and low-power modes. 

An additional specification to keep the mean torque value within of +1 percent of point or +0.12 

Nm, whichever is greater, ensures that the manufacturer targets a true nominal value even if 

there is substantial fluctuation in torque values during the sampling period. This prevents a 

manufacturer from intentionally biasing torque values low or high to take advantage of the wide 

tolerances that are necessary to accommodate the very low power levels. Mean values are 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

inherently much more stable than instantaneous values, so achieving the narrower range of 

values for the calculated mean torque should also be very achievable with current engines and 

with current test equipment. 

2.6 Production-line testing 

Comment Response 

EMA and OPEI commented that emission tests are often 

invalidated because one of the requirements specified in 

the test procedures was not met. Such requirements 

could be anything from a span check, a test condition 

parameter out of range, or any number of criteria 

required to conduct a valid test. Accordingly, they 

commented manufacturers should not be required to 

explain the reasons and report the emissions results from 

all tests that have been invalidated. Reporting of all test 

results would only be appropriate if EPA specifically 

recognizes that data obtained from an invalid test can not 

be utilized to determine compliance. By default, the 

new test should become the official test results. In EPA 

Phase 1 and 2 as well as CARB, this degree of 

authorization is not required. 

We agree that manufacturers should not need to get EPA 

approval before invalidating and repeating a test when a 

problem arises. However, we continue to be concerned 

that allowing manufacturers to omit reports of 

invalidated tests could result in manufacturers finding a 

way to invalidate a test based on the observation that the 

engine has failed or will fail to meet emission standards. 

We believe we can best address these competing 

concerns by requiring manufacturers to document their 

invalidated tests, including the reason for invalidating 

and any emission results that were recorded. The 

manufacturer could include an explanation describing 

why (or to what extent) the reported emission results 

from the invalidated test do not reflect the engine’s 

actual performance. We believe the proposed regulatory 

text in §1054.305(g) properly balances these concerns. 

OPEI commented that EPA Phase 2 and CARB all 

require that production line test reports be filed within 

45 days of the end of the quarter instead of 30 days, as 

proposed in §1054.3145. EPA is now requesting a 

different time period. OPEI requested keeping 

harmonization with CARB (report due 45 calendar days 

within end of test period). 

We agree that quarterly reports for production-line 

testing should be due 45 days after the end of each 

quarter, consistent with our approach under part 90. 

EMA commented on §1054.301(f) “When must I test 

my production-line engines?” EMA commented that the 

reference to 40 CFR 1068.27 is redundant and should be 

deleted. 

We agree that the reference to §1068.27 is not necessary 

and have removed it from the regulation. 

EMA commented on §1054.301(b) “When must I test 

my production-line engines?” EMA noted that the 

referenced section (§1054.32fs5) does not exist. EMA 

believes that the correct reference is to §1054.325. 

In regard to the reference to §1054.32fs5, we appreciate 

the comment and have revised the reference as 

recommended. 

EMA commented on §1054.305(d) “How must I prepare 

and test my production-line engines?” EMA commented 

that the requirement to adjust parameters must be clearly 

limited to adjustable parameters as defined in 

§1054.115(b). In addition, EMA commented that 

adjustment of the idle speed outside of the adjustable 

range as defined in §1054.305(d)(1) is not appropriate. 

Manufacturers determine idle speed ranges and 

tolerances. Adjustments outside of the manufacturers 

recommended tolerance are not appropriate. 

The proposed provision related to adjusting idle speed 

was derived from the current regulations at §90.508 

where we describe adjustments needed to operate an 

engine until it has reached stabilized emission levels. 

The original specification may have been related to the 

technology used for engines in that time frame. In any 

case, we are not aware of any need for making idle 

adjustments as described in the proposal. This includes 

a review of the testing we performed to establish the 

feasibility of the Phase 3 emission standards. We have 

therefore removed this provision from the final rule. 

ECO commented that EPA should allow small volume 

engine manufacturers to utilize the use of alternative 

testing methods (portable emissions analyzers) to 

demonstrate in-use field testing compliance for 

production units. 

We agree that the regulations should allow for simpler 

measurement methods for production-line testing, as 

described in Section 1.3.4. 

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Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

ECO 0712 

2.7 Equipment-manufacturer flexibilities 

2.7.1 Duration and extent of allowances 

What Commenters Said: 

OPEI commented that without the proposed equipment transition flexibility, the EPA 

Phase 3 program cannot be implemented without causing substantial and unnecessary injury to 

equipment manufacturers and to the market. Non-integrated OEMs producing outdoor power 

equipment must be able to stagger their complex and iterative-development and product 

evaluation process, for their most challenging catalyzed muffler configurations and for their 

difficult fuel tank technologies (such as roto-molding). OPEI commented that it supports the 

allowance of 30% of one year’s production for large OEMs. OPEI also supports the proposed 4-

year transition period of the 2011 through 2014 model years. 

OPEI commented that it strongly objects to EPA’s suggestion in the preamble that the 

proposed hardship relief measures in the Phase 3 regulation could somehow moot the 

independent need for the equipment-transitional flexibility program. Both proposed elements are 

critical to the industry and to the effective implementation of the final program. 

In response to EPA’s request for comments on whether the transition program for 

equipment manufacturers somehow moots the need for the proposed Delegated Assembly 

Program (or visa versa), OPEI commented that both programs are necessary and the two 

programs serve separate, distinct purposes. OPEI noted that EPA has failed to evaluate or 

quantify (in its administrative record or in its SBREFA process) the substantial economic 

damages that would result without either the proposed equipment flexibility or the Delegated 

Assembly provisions. OPEI commented that EPA’s other off-road emission regulations 

explicitly recognize the separate and independent need for Delegated Assembly, equipmenttransition flexibilities, and hardship relief. Consequently, it would be arbitrary for EPA to 

abruptly eliminate any one of these flexibilities for small engines. (Also included in Section 

2.8.1) 

EMA supported the proposed delegated assembly and equipment manufacturer flexibility 

provisions included in the NPRM. EMA commented that EPA must incorporate both of these 

programs into the final rule. If EPA were to adopt only the delegated assembly program and not 

the equipment manufacturer flexibility program (or visa versa), EMA commented that the 

functionality of the adopted program would be significantly impaired by the absence of the other 

program. (Also included in Section 2.8.1) The inclusion of aftertreatment systems into an 

equipment manufacturers’ exhaust system requires a much broader set of changes than just 

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packaging the catalyst into an existing muffler. In many cases, the introduction of an exhaust 

system that includes a catalyst will require a complete redesign of the exhaust system and/or the 

equipment in order to provide the necessary space and heat management of the exhaust system. 

This required redesign of the exhaust system/equipment is an enormous burden to the 

manufacturer and will create a significant strain on its resources. Accordingly, EMA believes 

that the flexibility provisions are absolutely necessary and must be incorporated into the final 

rule in order to ensure that manufacturers have the ability and time required to complete the 

necessary redesign. 

CARB commented that it believes the proposed transition program for equipment 

manufacturers is unnecessary since most equipment manufacturers are working together with 

their engine manufacturers to meet California’s Tier 3 standards. The equipment manufacturers 

are already working together to address concerns regarding lead-time, coordination, and other 

aspects involved in meeting the standards. CARB also commented that the proposed eligibility 

requirements for the TPEM program (i.e., only those manufacturers that have primary 

responsibility for designing and manufacturing equipment and whose manufacturing procedures 

include installing engines in the equipment are eligible) make it difficult to determine and 

enforce which manufacturers would actually qualify for the program. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

CARB 0682 

Our Response: 

In response to the comments that a TPEM program is not needed because of CARB’s 

Tier 3 program, EPA continues to believe a TPEM program is necessary for the manufacturers of 

Class II equipment. While CARB’s Tier 3 standards took effect in the model year 2008, the 

major engine manufacturers appear to be using ABT credits to certify to the standards since most 

of the engines certified with CARB in the Class II category have FELs above the Tier 3 standard 

of 8.0 g/kW-hr HC+NOx level. While it is not clear how long it will be before manufacturers 

redesign their Class II engines for California, it is likely that the engine manufacturers will not 

have a full set of engines redesigned until 2011 or later when EPA’s Phase 3 standards take 

effect. Because equipment manufacturers may need to make changes to some equipment designs 

to accommodate the redesigned Class II engines, EPA believes a TPEM program will help to 

ensure the transition to the Phase 3 standards goes smoothly for equipment manufacturers. EPA 

believes the basic framework of the TPEM program which allows manufacturers to use Phase 2 

engines over a four year period on up to 30% of their average Class II sales is appropriate and we 

are finalizing those levels in the final rule, as proposed. 

EPA agrees with the comments that the TPEM program and hardship provisions are both 

needed for the Phase 3 program. The hardship provisions are intended to help manufacturers that 

are facing economic hardship as a result of not being able to comply with the new standards. 

The criteria for qualifying for hardship are set at a relatively high level, which would likely be 

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difficult for a manufacturer to demonstrate if they were having difficulty redesigning only a few 

of their equipment models. The TPEM program allows an equipment manufacturer to deal with 

the models which are difficult to redesign without having to demonstrate that the company would 

experience hardship without the relief. Therefore, EPA agrees that both the TPEM program and 

the hardship provisions are needed and is retaining both of them for the Phase 3 program. 

EPA agrees with the comments that the TPEM program and the delegated assembly 

provisions are both needed for the Phase 3 program. The delegated assembly provisions allow 

manufacturers to independently source their exhaust systems based on the catalyst specifications 

determined by the engine manufacturer. However, the delegated assembly provisions will not 

ensure that an equipment manufacturer will be able to redesign all of their equipment models in 

time to accommodate a Phase 3 engine. Therefore, EPA agrees that both the TPEM program and 

the delegated assembly provisions are needed and is retaining them for the Phase 3 program. 

EPA disagrees with the comment that the criteria used to qualify manufacturers for the 

TPEM program makes it difficult to determine who is eligible. The purpose of the eligibility 

criteria is to ensure that only those companies that truly manufacture equipment can participate 

in the program. We do not want companies that only import complete equipment or companies 

that only install engines into a pre-existing equipment chassis to be eligible for the program. 

EPA has made this clear in the regulations. If there is any question regarding a manufacturer’s 

qualifications, EPA can request information from the manufacturer to determine if they actually 

are designing/manufacturing equipment and installing engines under the authority granted in 

Section 208 of the Clean Air Act. Section 208 (which applies to nonroad engines under section 

213(d) of the Clean Air Act) describes the information collection requirements for manufacturers 

and states that manufacturers must provide information that EPA may reasonably require to 

determine whether manufacturers have acted in compliance with regulations. For this reason, 

EPA is retaining the eligibility criteria for equipment manufacturers in the final regulations. 

2.7.2 Additional allowances for mid-sized companies 

What Commenters Said: 

OPEI commented that it supports the proposed mechanism to allow small and mid-sized 

OEMs to request up to a 70% production-based allowance (on a case-by-case basis). 

NESCAUM commented that they oppose the various provisions for small and medium 

volume manufacturers of engines and equipment that extend the use of Phase 2 compliant landbased SI engines for several years beyond the initial introduction of Phase 3 engines. However, 

they would not oppose a program whereby small businesses may apply individually to EPA for 

limited temporary relief from specific requirements due to economic hardship or other 

circumstances beyond their control. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

OPEI 0675 

NESCAUM 0641 

Our Response: 

EPA is retaining the special TPEM provisions for small- and medium-sized companies in 

the final rule. EPA believes that such companies face a bigger challenge with regard to 

equipment redesign than large companies because the small- and medium-sized companies tend 

to have fewer resources (i.e., both staff and money) available to work on equipment redesign. 

Therefore, EPA believes it is appropriate to offer more flexibility to these companies under the 

TPEM program. For small-sized manufacturers (defined in the regulations as producing no more 

than 5,000 pieces of nonhandheld equipment per year), the extra flexibility is automatic and 

allows them to exempt a cumulative 200% over four years. For medium-sized companies (i.e., 

those producing between 5,000 and 50,000 units with Class II engines), the manufacturer can 

request up to an additional 70% allowances over the four years, but must provide a variety of 

information to EPA to justify its request. 

In regard to the comment on relying on hardship requests instead of additional TPEM 

allowances for small- and medium-sized businesses, EPA does not believe that making a 

hardship provision the primary means for obtaining additional allowances would be workable for 

manufacturers or EPA. As noted above, smaller companies have limited resources to allocate to 

equipment redesign. Even though they may be small, many of these companies have a wide 

range of equipment offerings. EPA would rather see these businesses working on the equipment 

redesigns than pulling together information to request additional allowances from EPA. Plus, it 

potentially would place additional significant burden on EPA to review hardship applications, 

since there are over three hundred eligible small- and medium-sized equipment manufacturers. 

Therefore, EPA is retaining the TPEM provisions for small- and medium-sized businesses as 

proposed. 

2.7.3 Reporting and recordkeeping 

What Commenters Said: 

OPEI commented that it supports the proposed EPA notification, recordkeeping and 

ongoing annual reporting requirements for equipment manufacturers – these proposed provisions 

should be more than adequate to protect the integrity of the program. Any additional 

requirements would be overly burdensome. 

OPEI commented that it supports the proposed provision that would allow engine 

manufacturers to simply keep records showing their TPEM engines met the Phase 2 standards – 

rather than re-certifying those TPEM engines for the current model year. 

EMA commented that it agrees it is not appropriate or necessary to certify Phase 2 

compliant engines used in the equipment flexibility program. EMA commented that engine 

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manufacturers must be allowed to measure emissions prior to the catalyst, or with and without 

catalyst, during deterioration factor determination and certification emission testing being 

conducted for Phase 3 certification in order to generate the required data (i.e., data showing that 

the engine family, without aftertreatment, will comply with the Phase 2 standard) with the 

minimum amount of extra time and expense. Specifically, EMA commented that the provisions 

in §1054.625(j)(2) must allow the test data required by sub-paragraph (i) to be measured prior to 

the catalyst as part of the testing requirements for certification to Part 1054 Standards. 

EMA submitted two further comments on the regulatory language for the transition 

program for equipment manufacturers. First, EMA commented on §1054.625(g)(1)(iv) “What 

requirements apply under the Transition Program for Equipment Manufacturers?” EMA 

commented that equipment manufacturers will not be able to provide the name and address of 

the company that produces the engines that it will be using for the equipment exempted under 

this section prior to June 30, 2010. They commented that this requirement is impractical and 

should be deleted. Second, EMA commented on §1054.625(g)(2) “What requirements apply 

under the Transition Program for Equipment Manufacturers?” EMA commented that all 

manufacturers using the program should be required to comply with the reporting requirements 

set forth in this section for each year of the program, or until the manufacturer’s ability to use the 

program has expired. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

EPA is retaining the reporting and recordkeeping requirements for the TPEM program 

with some minor modifications, as noted below, in response to the comments summarized above. 

First, EPA is revising the provisions of §1054.625(j)(2)(i) to allow manufacturers to measure 

emissions prior to the catalyst to show that an engine would meet the Phase 2 standards. EPA 

believes it is appropriate to give manufacturers the option of measuring emissions either before 

the catalyst or with a non-catalyzed version of the exhaust system to show that an engine would 

meet the Phase 2 standards. Second, EPA is revising the provisions of §1054.625(g)i)(iv) to 

require equipment manufacturers to list the names of the manufacturer(s) whose engines they 

expect to use under the TPEM program. Because the information being requested is due before 

the TPEM program begins, EPA agrees that it would be difficult for an equipment manufacturer 

to know which manufacturer’s engines it would be using for the following four years of the 

TPEM program. However, equipment manufacturers should have an idea of which 

manufacturers’ engines it expects to use, and such information would be useful to EPA in 

monitoring the use of the TPEM program. 

In response to the comment on §1054.625(g)(2), we are not making any changes to the 

regulations. EPA believes the referenced language already requires equipment manufacturers to 

report their use of the TPEM program to EPA for each year they participate in the program. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

2.7.4 Labeling 

What Commenters Said: 

OPEI commented that to promptly respond to fluctuating demand, equipment 

manufacturers need the flexibility to designate their inventoried engines as either a Phase 3 

TPEM engine or as a Phase 3 “Delegated Assembly” engine. The final TPEM labeling scheme 

must provide the needed flexibility to the OEM to designate his Phase 3 engines – after he has 

ordered and received his engine families In this regard, OPEI supported EPA's proposed 

labeling provisions for the equipment manufacturers, under which his label would simply state 

the equipment manufacturer’s name and clarify that this is a TPEM engine. The engine 

manufacturer’s original emission label will appropriately provide all the engine-emission 

information. A full content, equipment manufacturer, emission compliance label would be 

confusing to customers and agency personnel – regarding the certification, emission warranty, 

and other information typically provided by the engine manufacturer as specified in the engine 

labeling requirements. In the cases where the engine originates as a Phase 3 compliant product 

utilizing the Delegated Assembly provisions, the equipment manufacturer re-labeling of the 

engine must not interfere with the ability of the ultimate consumer or the agency to accurately 

identify the important information included on the engine label. 

EMA commented that the content included on the engine/equipment manufacturer label 

should be sufficient to convey the fact that an engine is designated as a TPEM engine. EPA 

should not require the standard engine and/or equipment manufacturer emission compliance 

label to be placed on a TPEM engine. In the situation where a TPEM engine originates as a 

Phase 3 compliant engine under the delegated assembly program, the equipment manufacturer 

must be required to re-label the engine in a manner that will not interfere with the original engine 

label. EMA also commented on §1054.625(j)(2) “What requirements apply under the Transition 

Program for Equipment Manufacturers?” EMA commented that the reference in this section to 

the labeling requirement set forth in §1054.610(c)(7) is not appropriate and should be deleted. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

EPA is retaining the labeling provisions for TPEM equipment as proposed with only 

minor changes as described below. As supported by OPEI, the regulations allow a manufacturer 

to designate engines purchased under the delegated assembly program as either a TPEM engine 

(with a separate TPEM label applied by the equipment manufacturer) or a fully compliant Phase 

3 engine (with the appropriate aftertreatment installed by the equipment manufacturer). EPA 

notes that the TPEM label that must be placed on the equipment does require additional 

information than noted in OPEI’s comment supporting the proposed labeling provisions. In 

addition to stating the name of the equipment manufacturer and noting that the engine is a TPEM 

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engine, the label must also contain contact information for the equipment manufacturer and the 

year in which the equipment is produced. 

EPA disagrees with EMA’s comment that a standard engine/equipment label should not 

be required on a TPEM engine. EPA believes it is important to require a full engine label on the 

engine as well as an additional equipment manufacturer label to identify TPEM equipment. The 

information on the labels allows EPA and others to identify important information about the 

engine and equipment that could be needed to verify compliance with the TPEM program. In 

response to EMA’s comment on §1054.625(j)(2), EPA disagrees that the language is not 

appropriate. The citation is only a reference to the labeling requirements engine manufacturers 

must comply with for their delegated-assembly engines (which may end up as TPEM engines) 

and does not add any additional requirements. Therefore, EPA believes it is appropriate to 

include such a reference in the TPEM program regulations. It should be noted that in revising 

the regulations for the final rule, EPA has moved the labeling requirements for engines 

participating in the delegated assembly program to §1068.261, and therefore the language of 

§1054.625(j)(2) has been revised to reference the new section. 

2.7.5 Additional provisions for imported products 

What Commenters Said: 

OPEI commented that it supports the proposed special provisions, including bonding, for 

foreign equipment manufacturers and importers of equipment made outside of the U.S. using 

TPEM engines. 

Letters: 

Commenter Document # 

OPEI 0675 

Our Response: 

EPA is adopting the provisions for foreign equipment manufacturers and importers of 

equipment made outside of the U.S using TPEM engines as proposed. 

2.7.6 Relationship to tank permeation requirements 

What Commenters Said: 

OPEI commented that it supports the proposal to also allow equipment manufacturers to 

use non-compliant rotational-molded, “flex” fuel tanks on any of their equipment with TPEM 

engines. OPEI objects to EPA’s proposed limit on “flex” fuel tanks requiring the OEM to first 

use up available banked credits or allowances from his early compliance with the fuel tank 

permeation requirements. This restriction takes away from the incentive for manufacturers to 

introduce compliant tanks early or to produce tanks with FELs below the standard. In addition, 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

they believe this restriction will overly-complicate the administration of the program with no 

benefits. 

OPEI submitted an additional comment after the close of the comment period regarding 

rotational-molded fuel tanks. They supported a delay in the permeation requirements for 

rotational molded fuel tanks instead of the proposed linkage to the TPEM program. 

Letters: 

Commenter Document # 

OPEI 0675 

OPEI 0793 

Our Response: 

 EPA is revising the allowance for equipment manufacturers to use non-compliant 

rotational-molded fuel tanks on their equipment with TPEM engines for the final rule. EPA 

continues to believe that equipment manufacturers may face challenges in transitioning all of 

their rotational-molded fuel tanks to meet the new permeation standards in the timeframe for the 

new standards. However, based on discussions with manufacturers, we have been convinced that 

there is not necessarily a direct link between the potential TPEM engines/equipment and the use 

of rotational-molded tanks on those engines/equipment. We are therefore allowing equipment 

manufacturers to use noncompliant rotational-molded fuel tanks for two additional years on 

limited numbers of 2011 and 2012 model year equipment using Class II engines, regardless of 

whether the equipment is part of the TPEM program. Equipment manufacturers may use 

noncompliant rotational-molded fuel tanks if the production volume of the fuel tank design used 

in Class II equipment models is collectively no more than 5,000 units in the 2011 model year. In 

the 2012 model year, equipment manufacturers may use noncompliant rotational-molded fuel 

tanks if the production volume of the fuel tank design used in Class II equipment models is 

collectively no more than 5,000 units in the 2012 model year, but the total number of exempted 

rotational-molded fuel tanks across the manufacturer’s Class II equipment is limited to 10,000 

units. If production volumes are greater than 5,000 for a given fuel tank design, all of those 

tanks must comply with emission standards. Tank designs would be considered identical if they 

are produced under a single part number to conform to a single design or blueprint. In addition, 

tanks would be considered identical if they differ only with respect to production variability, 

post-production changes (such as different fittings or grommets), supplier, color, or other 

extraneous design variables. 

2.8 Delegated assembly 

2.8.1 Need for delegated assembly 

What Commenters Said: 

OPEI noted that EPA has proposed a permanent Delegated Assembly program (see 

§1054.610) specifically designed for small spark-ignition engines. The purpose of this program 

is to create a very protective compliance program that would allow non-integrated engine 

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manufacturers to distribute their certified engines without the required emission-related parts 

(i.e., catalyst) that are listed on and required for EPA certification. OPEI elaborated as follows: 

First, in the initial stage of developing the after-treatment system, the engine manufacturer must determine 

the catalyst-specific parameters including substrate size, precious metal loadings, and engine performancerelated specifications to allow the catalyst to be packaged or canned so that it can be installed. The catalyst 

selection and packaging designs must provide the intended exhaust emission conversion and also manage 

exhaust and cooling air flow to ensure all safety concerns are addressed, and to manage sound and tonal 

qualities. 

Second, the engine manufacturer identifies the "standard" muffler packages that meet the criteria identified 

above. In many cases there is only one "standard" muffler configuration designed and developed by the 

engine manufacturer. Engine manufacturers cannot specify the diversity of mufflers required to fit into 

specific equipment or to install packaged catalysts into such customized mufflers. Such customization is a 

very time-consuming and resource-intensive exercise that adds significantly to the complexity of the engine 

manufacturer's product as supplied to the equipment manufacturer. It is highly unlikely that engine 

manufacturers would be able to fundamentally change their business structure to supply customized 

mufflers in the future. Such a change in their business models would be tantamount to asking a major 

international supplier of lumber, which sells large volumes of stock lumber to less than one hundred 

wholesalers, to only sell customized, small volume cabinets or furniture to thousands of individual 

customers. 

Third, for most Class II products, the catalyst prescribed by the engine manufacturer must be packaged into 

the muffler system prescribed by the equipment manufacturer because there is insufficient space to allow 

separate catalyst and muffler systems. Consequently, for the vast majority of Class II engines, engine and 

equipment manufacturers must depend on their independent muffler suppliers, who exclusively have the 

capacity and expertise to install catalysts properly into their customized mufflers. For most Class II 

products, the independent muffler supplier is the only party who can practically install catalysts into the 

mufflers for the vast majority of Class II engines and customize these products for the various equipment 

designs. 

Fourth, without Delegated Assembly, the engine manufacturer would have to include specific catalyzed 

mufflers in the box with his shipped engines. The OEM would not be able to use many of these purchased 

and shipped mufflers because they would not fit into his final, complete applications. This problem results 

from the fact that an equipment manufacturer cannot wait for specific orders from his downstream retailers 

before he orders his engines. The OEM must typically purchase and receive large volumes of the same 

engine family, which must be used in many different models. Each model will likely have different or 

unique muffler configurations. Unpredictable market demand will drive the OEMs ultimate production of 

specific equipment models and therefore the volumes of the different engine-muffler combinations the 

OEM will ultimately build. When the engine is shipped to the OEM, neither the engine manufacturer, nor 

the equipment manufacturer may know which exact equipment models and/or which muffler configurations 

wil be used with each specific engine family. 

OPEI concluded their argument by noting that EPA must finalize a practical Delegated 

Assembly program which allows direct shipments of catalysts from a catalyst supplier to a 

muffler supplier, who will be accountable and responsible for proper catalyst canning and will 

install the required catalyst in each application, prior to shipping the specialized catalyzed 

muffler to the OEM. 

OPEI commented that as part of this preamble discussion, EPA incorrectly suggests that 

many muffler geometries are fairly uniform and that it should be possible to produce more 

standardized, “stock” mufflers that could be supplied directly through the engine manufacturer 

(see 72 Fed. Reg. at 28152). OPEI believes EPA grossly over-simplified the problems and 

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challenges associated with applying and packaging exhaust/muffler systems onto a wide variety 

of equipment. While many mufflers have a somewhat common cylindrical geometry, the 

muffler mounting brackets, internal sound bafflers, and the header and tailpipe geometries vary 

greatly. One supplier of mufflers and exhaust components, released just under 100 unique 

components last year alone to address the variations in the muffler and exhaust configurations 

required to fulfill the OEM packaging requirements for these small engine applications. OPEI 

estimates that there are over 1000 different muffler configurations for these engines in the 

national marketplace today. 

Traditionally, the muffler design is a compromise between exhaust back pressure, as 

prescribed by the engine manufacturer for emission compliance, and sound attenuation. The 

various applications these mufflers are installed in have unique trade-offs. OPEI commented that 

EPA needs to consider the unique requirements of the small engine market that serves 

applications such as: portable power, utility vehicles, golf carts, construction equipment, light 

towers, agricultural, etc. Other equipment may also have different requirements which can 

dramatically affect muffler designs. The application specific trade-offs often lead to unique 

internal design features of the muffler for each engine, in addition to external differences. 

Of course, the principal challenge of muffler design is thermal management issues, which 

are safety-related and are a further constraint to application designs. The addition of a catalyst 

will create additional complexities and challenges, especially when dealing with off-nominal 

conditions such as engine misfire situations (See Sections III and IV above). The thermal 

management issues lead to a variety of different insulation and heat shield scenarios, which 

result in unique muffler configurations specific to the product design. Current experience with 

the development of catalyzed muffler systems that meet California Tier III regulations has 

confirmed that these product-designs and complex heat and emission-related challenges will 

demand customized mufflers that are supplied by a third party. 

For all these reasons, OPEI commented that it does not believe that there will or can be a 

shift in the market place towards standardized “stock” muffler designs. OEMs will continue to 

depend on customized mufflers to facilitate their product designs as required to service their 

diverse markets. Consequently, OPEI commented that the Delegated Assembly Program is 

absolutely crucial to satisfy the market needs of the small SI applications to obtain catalyzed 

mufflers from their muffler suppliers. 

OPEI noted that EPA has requested comment on whether the transition program for 

equipment manufacturers somehow meets the need for the proposed Delegated Assembly 

Program (see 72 FR 28152). Conversely, EPA requested comment on whether manufacturers 

will need the equipment-transition program (described above in Section III) if they can 

independently source their exhaust systems based on the Delegated Assembly Program (see 72 

FR 28154). OPEI responded that the answer to both of these questions is no. OPEI believes 

both programs are necessary. In fact, the two programs serve separate, distinct purposes. 

Finally, OPEI commented that EPA has failed to evaluate or quantify (in its administrative 

record or in its SBREFA process) the substantial economic damages that would result without 

either the proposed equipment flexibility or the Delegated Assembly provisions (proposed in 

§1054.610). EPA’s other off-road emission regulations explicitly recognize the separate and 

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independent need for Delegated Assembly, equipment-transition flexibilities, and hardship relief. 

Consequently, OPEI commented that it would be arbitrary for EPA to abruptly eliminate any one 

of these flexibilities for small engines. 

EMA supported the proposed delegated assembly and equipment manufacturer flexibility 

provisions included in the NPRM. EMA commented that EPA must incorporate both of these 

programs into the final rule. If EPA were to adopt the delegated assembly program only and not 

the equipment manufacturer flexibility program (or visa versa), the functionality of the adopted 

program would be significantly impaired by the absence of the other program. 

Honda noted that in the market today for small engine products, multiple businesses 

cooperate to produce parts for numerous small engine powered machines that are the design, 

production, and marketing responsibility of a multitude of independent equipment 

manufacturers. Each manufacturer in the process, including the final equipment manufacturer, 

may design and manufacture, design and outsource the manufacture of, or simply purchase an 

existing part. This distinction is important to identify who should take responsibility for the 

actual performance of the part. 

Today, for larger sales volumes, engine manufacturers cooperate closely with equipment 

manufacturers to meet the equipment manufacturers’ product needs. At a smaller manufacturing 

volume there is less direct contact but the process of matching the engine to the equipment and 

the documentation of this process are still in place. The key to the appropriate use of a specific 

engine in a specific application is based on a basic engineering evaluation of the engine matching 

document and of the general instructions for engine use. This concept works well when the 

equipment manufacturer uses the engine as it was built by the engine manufacturer. However, in 

actuality, a wide variety of equipment is used on an even wider variety of tasks and the 

equipment manufacturer must be able to tailor the engine to fit both the equipment and the task. 

For example, a trencher, earth rammer, concrete equipment, and a lawn mower work in similar 

dust and debris environments, but the packaging of a single engine model in the least vulnerable 

location to make a workable machine can result in very different requirements. The proposal’s 

preamble includes a comparison of a handful of mowing equipment and concludes that it would 

be possible to package a single engine design in all machines. Honda believes this fails to look 

beyond the most popular use of small SI engines and does not recognize the significant diversity 

of small engine powered types of equipment. 

Honda commented that the need for an equipment manufacturer to have flexibility in the 

final assembly of engine intake and exhaust components is critical for both large and small 

volume equipment manufacturers. An engine manufacturer cannot economically stock or supply 

in a timely manner, the array of components required by the diversity of the market. Only the 

equipment manufacturer that functions as an independent business, striving to create or improve 

a machine’s design and target a value price, is in a position to create the best product for its 

customers. Similarly, the engine manufacturer is in the best position to provide engine matching 

tools and instructions that ensure the final engine assembly will be in compliance with applicable 

regulations and will match the required certification information. In many cases the engine 

manufacturer and the equipment manufacturer will work jointly, or with a third party, to ensure 

that the design is compliant with the regulations. 

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Honda suggested two alternatives to the proposed means of ensuring that the final 

assembly of the equipment will comply with the regulations and answer the concern about 

enforcement of the regulation. 

1) Honda noted that in some cases the engine and equipment manufacturer (and 

potentially a third party supplier or testing facility) work together to fulfill the equipment 

manufacturer’s product design targets. During that process, they generate enough information 

and working instructions that the equipment manufacturer could then submit an abbreviated 

certification form and be identified to the EPA as the manufacturer with responsibility for the 

specific configuration of that engine model used in the equipment manufacturer’s particular final 

product. EPA could then assume its rightful role and use the Selective Enforcement Audit 

mechanism or confirmatory testing to verify that the product meets the requirements of the 

regulation. EPA would also know in advance which manufacturer is taking responsibility for 

what part of the final assembly. 

2) Honda suggested that EPA supplement the definitions in 1068.101(b) and the text in 

1054.20 so that it is clear that failure to follow the engine manufacturer’s instructions for 

delegated assembly is tampering and/or falls into the category of a defeat device. This option 

could be applied when the equipment manufacturer does not interact directly with the engine 

manufacturer and an abbreviated certificate is not submitted. The equipment manufacturer in 

this case would need to follow the engine matching and installation instructions using its own 

data or engineering evaluation. This type of situation could also be treated in a manner similar to 

1060.101(f) in the evaporative emissions section where the equipment manufacturer is “deemed 

to be certified.” EPA will then have the necessary enforcement authority when they perform a 

field or factory audit of equipment. A thorough examination of the steps involved in engine 

distribution, product design and manufacturing, and the role of third party suppliers should make 

it possible to retain EPA authority to ensure emission compliance without disrupting the ability 

of both engine and equipment manufacturers to deliver innovative and value priced product to 

the consumer. 

CARB commented that EPA’s overall approach to the proposed delegated final assembly 

is reasonable and corresponds to CARB’s current certification procedures. CARB believes that 

EPA should require engine manufacturers to be held responsible for ensuring that the catalysts 

are installed on the engines that are accumulating credits. Since the engine manufacturer is 

receiving the benefit of accumulating credits for these particular engines, they should make sure 

that the catalysts are being installed. Any instance of an engine found without a complete 

emission control system, as certified, should be treated as noncompliant, with all possible 

penalties. Allowing any exceptions would send an inappropriate message to the manufacturers. 

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Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

CARB 0682 

Honda 0705 

Our Response: 

An important point to clarify before evaluating the commenters’ arguments in support of 

delegated assembly is that under any conceivable regulatory scenario we would require mufflers 

that are shipped directly from the muffler manufacturer to the equipment manufacturer to be 

specifically included in the engine manufacturer’s application for certification. While the 

commenters describe or imply a need for equipment manufacturers to have an unrestrained 

ability to work out design parameters with muffler manufacturers, we have neither proposed nor 

considered such an outcome. OPEI’s description betrays an understanding that equipment 

manufacturers should have an unrestrained ability to change muffler designs parameters even if 

that affects emission levels. We acknowledge that muffler design involves compromises 

between back pressure, thermal management, and sound attenuation. A muffler design that is 

not specifically part of the engine manufacturer’s application for certification will inevitably 

involve design parameters that favor non-emission factors over factors important for controlling 

emissions. The result would be a noncompliant engine and a situation where the certifying 

manufacturer will disclaim any responsibility for the performance of its own engine. This is 

clearly unacceptable. The certifying engine manufacturer is responsible for ensuring compliance 

and therefore needs to be in control of design variable that could affect whether engines meet 

emission standards or not. 

We agree with the commenters that muffler manufacturers play an important role in 

incorporating an engine manufacturer’s specified catalyst into a muffler that appropriately 

controls air flow for maintaining catalyst performance, managing external surface temperatures, 

and provides proper sound attenuation. However, this fact alone does not demonstrate that 

equipment manufacturers need to be able to get customized mufflers for every equipment model. 

There are many examples of current engine and equipment models in which mufflers and 

catalysts flow from component manufacturer to engine manufacturer to equipment manufacturer, 

with varying degrees of involvement by equipment manufacturers in the design parameters of the 

exhaust components. Regardless of the extent to which engine and equipment manufacturers 

would work out arrangements for delegated assembly, every engine manufacturer will need to 

certify their engines using some number of stock mufflers. In the transition to new emission 

standards, engine and equipment manufacturers will work out the degree to which multiple 

muffler configurations will be needed to meet the design needs for the range of equipment 

models that will be affected. The Transition Program for Equipment Manufacturers provides 

four years of a more flexible transition to allow for these negotiations and adjustments. 

OPEI’s analogy to a lumber supplier needing to start selling custom cabinets exaggerates 

the business dynamic in question. The comparison does not acknowledge that engine 

manufacturers are already selling the new product (engines with mufflers) in many cases, that 

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engine manufacturers are liable for the performance of the finished product, or that equipment 

manufacturers have to design their equipment around a given muffler design, whether or not the 

muffler is manufactured to their specifications. Our objective is not to create a better analogy, 

but the weakness of this comparison highlights our concern that the commenter is unable to 

provide a straightforward rational assessment of the situation. 

The fundamental gap in the argument presented is the interplay between equipment and 

engine manufacturers in coming up with final design specifications. We believe that purchasing 

agents and design engineers working for the equipment manufacturers will have an important 

role in moving successfully into a new era in which engine manufacturers have a legal 

responsibility to ensure that exhaust systems are properly designed and assembled for 

compliance with exhaust emission standards. Purchasing agents for equipment manufacturers 

buying large volumes of engines can have a very significant influence over the engine 

manufacturer’s design parameters. As a result, we would expect these dominant equipment 

manufacturers to effectively dictate muffler designs to ensure that available stock mufflers meet 

their needs, considering physical dimensions, thermal management, and sound attenuation. 

Engine manufacturers would want to make a reasonable number of muffler configurations 

available, so we would envision this process playing out such that several stock mufflers would 

be available. 

Even under the broadest conceivable approach to delegated assembly, equipment 

manufacturers will be unable to get customized mufflers for their small-volume products. Since 

engine manufacturers need to agree to add each muffler configuration to their application for 

certification and enter into a contract with equipment manufacturers creating customized 

mufflers, there will be many cases where this option isn’t viable or cost effective. Engine 

manufacturers may decide that a custom design presented to them by an equipment manufacturer 

is unacceptable, or they may be unable to provide the resources to make this determination. 

They may be unwilling to trust the equipment manufacturer to properly procure parts for and 

assemble the final products such that every engine is in its certified configuration before delivery 

to the end user. These potential complications were given credence by one manufacturer who 

communicated to us that their plan is to participate in delegated assembly using a custom muffler 

from an equipment manufacturer only if the equipment manufacturer performs a complete round 

of testing, including service accumulation over the engine’s full useful life, to show that the new 

muffler design complies with the underlying certificate. This is more than we require currently, 

but it illustrates a prudent approach by engine manufacturers to protect themselves from the 

liability of delegating important compliance responsibilities to other companies. 

Design engineers working for equipment manufacturers also have an important role to 

play in this process. While OPEI suggests that equipment manufacturers will need to 

discontinue production of equipment models if they can’t procure customized mufflers, we 

believe this ignores the equipment manufacturers’ ability to adjust the designs of their equipment 

to accommodate a specific muffler configuration supplied to them by an engine manufacturer. 

As noted in the comments, there are many examples of custom muffler designs that are tailored 

to a specific type of equipment. If that custom muffler was no longer available, design engineers 

for the equipment manufacturer could, for example, adjust mounting brackets, accommodate a 

different muffler orientation, or otherwise make the muffler fit to allow the equipment to 

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satisfactorily perform its function. While there would be a significant effort and expense to 

modify equipment designs just for a muffler change, the incremental effort of accommodating a 

muffler change as part of a broader equipment redesign is much smaller. Our understanding is 

that equipment models are typically redesigned every five to eight years. (The cost estimates in 

Chapter 6 of the Final Regulatory Impact Analysis take into account the cost of modifying 

equipment as part of an overall redesign.) 

Customizing mufflers for sound attenuation and thermal management should be easily 

managed by the engine manufacturer. We believe engine manufacturers will be strongly 

motivated to meet market demands by working with muffler manufacturers to create a menu of 

stock mufflers that provide varying degrees of sound attenuation. The engine manufacturer 

would be well positioned to efficiently design for sound attenuation by integrating that effort into 

an overall design program to develop a catalyst and exhaust configuration that meets emission 

standards. Similarly, thermal management of exhaust surfaces is fundamentally related to engine 

operation. Engine manufacturers are best positioned to design mufflers (in cooperation with 

muffler manufacturers) such that all possible engine operating modes are considered when 

properly designing a muffler to avoid any risks associated with high surface temperatures. 

We would also caution against the tendency to overstate the extent of change in muffler 

designs resulting from our proposal. Our testing to support the feasibility of the new emission 

standards showed that an existing muffler could be modified to incorporate a catalyst primarily 

by rearranging the internal flow paths, without significantly changing the muffler’s outer 

dimensions. We also showed that this could be done without significantly increasing external 

surface temperatures. This is not to say that engine and muffler manufacturers won’t develop 

mufflers that have notable differences from current designs, rather that we are not expecting 

dramatic changes in these designs. As a result, we believe the design challenge for equipment 

manufacturers will mostly involve the transition from customized to stock mufflers. As noted 

above, this will involve little or no change for high-volume products, because equipment 

manufacturers will in effect dictate that their custom design becomes one of the standard 

configurations from the engine manufacturer. For the remaining equipment models, we are 

confident that equipment manufacturers will be able to make the changes needed to 

accommodate a stock muffler, such as rearranging mounting brackets, repositioning mufflers, or 

otherwise to make the mufflers fit into the overall equipment design. 

We also believe that the commenters grossly overstate the current need for customized 

mufflers. We stand by our observations in the preamble of our proposed rule regarding the 

standardization of mufflers in current products. The products we observed with relatively 

uniform muffler configurations represented a wide range of models, brands, and applications. 

Moreover, the general observation was that the nature of mufflers and exhaust systems is that 

they need space to safely and effectively route hot exhaust gases away from the engine and into 

the atmosphere. We suspect that the large number of muffler configurations produced today is 

mostly related to proper mounting, orientation, and plumbing to fit the muffler into the 

equipment. Redesigning most equipment for a standard muffler configuration should involve 

only modest changes to shift the position of the muffler or to change the cage or shielding or 

frame that currently houses the muffler. That is not to say that there aren’t examples of mufflers 

that are more carefully tailored to specific equipment models, rather that we believe this practice 

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is much less common than suggested by the commenters. We understand that these changes will 

take time and effort, but we believe that they are well within reach for equipment manufacturers, 

especially as part of an overall equipment redesign. The time available before the standards take 

effect and the flexibility provisions built into the final rule should allow equipment 

manufacturers to work with engine manufacturers for an orderly transition in their equipment 

designs to the extent that is needed. 

Two examples from observations made at the 2006 Louisville Expo for lawn and garden 

equipment highlight the difference in opinion as to the extent of the redesign that will be 

necessitated by this rulemaking. First, we observed a four-wheel drive utility vehicle in which 

the compartment to house the engine and the whole exhaust system were internal to the body of 

the vehicle, located primarily behind and under the driver’s seat. This would seem to be a prime 

example of a need for a specialized muffler confined in a limited space, since every amount of 

space devoted to the engine and exhaust system was space made unavailable for passengers and 

payload. Despite this trade-off of utility and comfort, the vehicle design included a relatively 

large cavity for the muffler and other exhaust components. Clearly this amount of space was 

needed to provide adequate clearance from the exhaust surfaces to avoid exposing other parts of 

the vehicle to such high temperatures. We suspect that an effort to change to a different muffler, 

even one with a very different shape, would not be impossible. 

In a second example, an equipment manufacturer complained vehemently that their 

engine supplier insisted on supplying the muffler with the engine, leaving them with the 

extraordinary burden of fitting the stock muffler into their equipment. The representative 

claimed to have a worst-case equipment model on display– a riding lawn mower with several 

premium features, including a plastic collection bin mounted behind the mower and over top of 

the exhaust system. In this case the muffler was mounted in a cage for preventing accidental 

contact with hot exhaust surfaces, again with rather generous spacing around the muffler. It was 

apparent that changing this equipment model would require significant time to address design 

concerns such as fit, weight distribution, exposure to radiant heat, etc. We believe, however, that 

these design challenges could all be addressed even by a company with very limited engineering 

resources. Having several years to plan and execute these changes seemed to be a very 

reasonable expectation, even in this worst-case configuration. These observations support our 

conclusion that equipment manufacturers will be able to respond to changing muffler designs in 

the context of the Phase 3 standards, especially if they have a transition period that will allow 

them to factor in the necessary changes in advance. Furthermore, the fact that there is already an 

example of an engine manufacturer telling its customers that only stock mufflers are available 

demonstrates that this can be a business decision negotiated between companies rather than one 

that is inherently and necessarily subject to the control of equipment manufacturers. 

It is important to note the comparison with nonroad diesel engines, as we are expecting 

those engines to include new aftertreatment devices to meet Tier 4 standards. These 

aftertreatment devices will be new, relatively large components added to exhaust systems (not 

incorporated into existing mufflers) that equipment manufacturers will need to accommodate. 

We will allow the equipment manufacturers the flexibility of using limited numbers of previoustier engines for several years (much like the Transition Program for Equipment Manufacturers 

described above). There is an expectation for the long term that equipment manufacturers will 

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be able to use stock aftertreatment devices from the engine manufacturers as part of their 

equipment design. The expected design effort for Small SI equipment pales in comparison to the 

efforts expected from the nonroad diesel equipment manufacturers. We also note that the 

program for nonroad diesel engines is the only other one in which we have adopted both 

delegated assembly and a Transition Program for Equipment Manufacturers. These are not 

universal and inherent aspects of our compliance programs, as suggested by OPEI. 

Aside from the question of who designs catalyst and muffler configurations, we 

acknowledge that there are business reasons to prefer shipping mufflers directly from the muffler 

manufacturer to the equipment manufacturer. This was the original purpose of the delegatedassembly provisions we adopted in §1068.260. OPEI’s comments appropriately describe the 

situation for an equipment manufacturer in that situation, needing to manage large numbers of 

equipment models, each with multiple engine and muffler configurations. The dynamics of 

managing inventories to produce all of these equipment models causes us great concern that 

every assembled unit is built properly in its certified configuration. This is the basis of the 

extensive protective measures we believe are necessary to ensure that engines are properly 

assembled. 

We also acknowledge that, with proper constraints and controls, engine manufacturers 

can work with equipment manufacturers that they trust to install properly designed catalyzed 

mufflers. Some of these mufflers may have been designed by the equipment manufacturer 

together with the muffler manufacturer and coordinated with the engine manufacturer, such that 

final engine assemblies will meet the required standards. As a result, we believe it is appropriate 

for the final rule to include a carefully constructed delegated-assembly program for Small SI 

engines in addition to the Transition Program for Equipment Manufacturers that will allow 

manufacturers a flexible transition period to incorporate any engine or muffler design changes 

resulting from compliance with the Phase 3 standards. This transition period will allow time for 

market forces to work toward a sensible degree of accommodation between engine and 

equipment manufacturers as they find the best way of dividing design and assembly 

responsibilities such that they preserve the engine manufacturers’ ultimate control over design 

and compliance responsibility and at the same time recognize the equipment manufacturers’ need 

to make equipment that functions within the limitations in muffler design and specifications 

required due to certification. There is a continuing need for delegated assembly after this 

transition period, but we believe this is more of a business decision regarding the most efficient 

method of designing and shipping product than an inherent necessity for equipment 

manufacturers to be able to produce equipment with certified engines that can be used in a 

multitude of applications. Accordingly, we are adopting delegated-assembly provisions for 

Small SI engines that include greater initial flexibility, after which a narrower set of provisions 

apply, as described in Section 2.8.2. 

We believe the proposed regulations already reflect Honda’s suggested approaches for 

dividing responsibilities among engine and equipment manufacturers. The idea that equipment 

manufacturers rely on an abbreviated certification for designs that fall outside of the engine 

manufacturer’s certified configurations was proposed in §1054.612. This gives the equipment 

manufacturer the ability to recertify an engine family without generating a new deterioration 

factor or conducting production-line tests. Also, the current regulations in §1068.105 clearly 

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state that equipment manufacturers violate the tampering prohibition if they fail to follow an 

engine manufacturer’s installation instructions. However, it would not be appropriate for the 

engine manufacturer’s installation instructions to simply specify broad design parameters that 

equipment manufacturers would then follow, with some unspecified testing or engineering 

evaluation to support a conclusion that the resulting engine design is covered by a certificate. 

The “deemed certified” approach proposed in §1060.101 is limited to requirements that are so 

straightforward that they can be established by simple observation. Evaluating compliance with 

exhaust emission standards is far from straightforward. We therefore believe that approach of 

considering engines certified through an informal demonstration does not meet the requirement 

under the Clean Air Act for engines to be certified based on a demonstration that measured 

emission levels are within prescribed limits. We also believe manufacturers would be unwise to 

delegate this level of responsibility to another company, since they would be held liable for any 

noncompliance resulting from any designs that fall short of meeting emission standards. 

2.8.2 Specific provisions for delegated assembly 

What Commenters Said: 

General: 

OPEI noted that EPA requested comment on the need for the specific provisions of the 

Delegated Assembly for small engines with catalyzed mufflers in comparison to other non-road 

engine/equipment categories as defined by current regulations (72 Fed. Reg. at 28149-28152). 

OPEI commented that the proposed small SI provisions are essential in order to respond to the 

following unique constraints of the small spark ignition engine and equipment industry: (1) the 

cost sensitive nature of the products produced; (2) the retail distribution system employed; and 

(3) the diversity of products. OPEI commented that the current generic Delegated Assembly 

Program fails to respond to each of these unique factors and would create totally impractical 

burdens (see §85.1713 and §1068.260). In turn, this would have a dramatic, adverse impact on 

both large and small outdoor power equipment manufacturers resulting in the elimination of 

many equipment models. 

EMA commented that the Small SI engine and equipment industries have specific needs 

regarding delegated assembly that have been appropriately balanced with the regulatory 

requirements as specified in §1054.610 of the proposal along with the other changes 

recommended by EMA in this section. EMA commented that the final rule should not integrate 

these requirements with the general provisions prescribed in 40 CFR Part 1068, but should rather 

retain their independence in Part 1054. 

Written confirmation: 

OPEI commented that the regulations need to allow a small engine manufacturer to 

obtain written confirmation (within 30 days after shipping engines) that his OEM customer has 

ordered the appropriate catalysts as part of the initial shipment -approval process for delegated 

engines. 

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EMA commented on §1054.610(c)(9) “What is the exemption for delegated final 

assembly?” EMA commented that the proposed requirement is not viable. An engine 

manufacturer cannot “have written confirmation . . . for an initial shipment of engines...” and 

also “. . . receive the written confirmation within 30 days of shipment.” Accordingly, EMA 

commented that the language should be revised to read as follows: “You must advise the 

equipment manufacturer that (i) written confirmation that the appropriate aftertreatment has been 

ordered is required within 30 calendar days of the initial engine shipment for a given model year; 

and (ii) if written confirmation is not received future engine shipments will not be allowed. The 

equipment manufacturer can meet the written confirmation requirement by notification to the 

engine manufacturer that engines will be used under the equipment manufacturer flexibility 

program defined in 40 CFR Part 1054.625.” 

Audits: 

OPEI commented that engine manufacturers' audits of their respective OEM production 

practices (and confirmation that products meet the certified configuration) can be effectively 

accomplished in many different ways. The regulatory requirements should not constrain the 

options an engine manufacturer may utilize. OPEI commented that the final program should 

allow the small engine manufacturers to conduct audits of either the OEM’s production process 

or his final assembled products (pursuant to EPA’s proposal). 

EMA commented that there are many different ways an engine manufacturer can 

effectively audit an OEM’s production practices and confirm that products meet the certified 

configuration. The regulatory requirements should not place undue restraint on the engine 

manufacturer’s ability to use the many viable options available. In order to accommodate the 

wide variety of engine manufacturer/OEM business relationships, the auditing requirements must 

be flexible. Each engine manufacturer has a variety of OEM customers ranging from the very 

sophisticated large business (where engine orders/deliveries are coordinated with equipment 

build schedules for just in time production) to small companies that may only place a single 

order each year. EMA commented that requiring certification documentation of all the various 

options an engine manufacturer may utilize is burdensome and ineffective. Certification 

documentation should be limited to an acknowledgement from the engine manufacturer of the 

need for the required audits and its intent to utilize the delegated assembly provisions. 

EMA commented on §1054.610(c)(10) “What is the exemption for delegated final 

assembly?” The requirement to select individual equipment manufacturers equally among the 

volume quartiles is overly prescriptive with no added benefit to the environment. EMA 

commented that this section should be revised in order to provide for selection of equipment 

manufacturers from each quartile as much as possible. This will allow engine manufacturers to 

select equipment manufacturers for auditing based on their confidence in the equipment 

manufacturers processes. 

Point of final assembly: 

OPEI and EMA commented that the “point of final assembly” (when the exemption no 

long applies) will vary depending on the equipment manufacturer production process. Engines 

that are scheduled to be utilized in one equipment model may be pre-assembled with the 

expected exhaust system. Due to production-demand changes, these engines may be returned to 

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inventory with the intent of later assembly only to be reconfigured at a later date for installation 

into different equipment. This may result in the exhaust system being replaced. For purposes of 

determining whether an exemption has expired, OPEI commented that the “point of final 

assembly” should be defined as the point at which the final equipment is totally complete and 

ready to be introduced into commerce. 

Labeling: 

OPEI commented that if there are provisions required for the designation of Delegated 

Assembly engines on the emission compliance label, OPEI supports the use of an identifying 

mark on the permanent label, such as “DA” as an approved abbreviation for “Delegated 

Assembly.” 

CARB recommended a change to the proposed labeling requirements. EPA is proposing 

a partially completed label (temporary label) be placed by the engine manufacturer which would 

subsequently be replaced by a final permanent label by the equipment manufacturer upon 

completion of delegated assembly. Since the engine manufacturer is ultimately responsible for 

the final assembly and product as the holder of the Executive Order (in California) and 

Certificate of Conformity (federally), CARB recommended requiring the following: 

Option 1: The engine manufacturer applies a partial permanent label, and following 

delegated assembly, the equipment manufacturer adds a supplemental permanent label (placed 

just below the original label) completing the labeling requirement. This procedure is similar to 

the approach used for rebuilt/replacement off-road compression-ignition engines. 

Option 2: The engine manufacturer applies a complete permanent label and ships the 

incomplete engine to the equipment manufacturer who subsequently completes the delegated 

assembly. This option would have an added requirement that the engine manufacturer must 

demonstrate, as part of the certification process, that there are quality control procedures in place 

to ensure that the final assembly occurs correctly. 

Production-line testing: 

OPEI and EMA commented that engine manufacturers should be allowed flexibility 

regarding the equipment manufacturer supplied exhaust systems required for PLT testing, 

including the ability to inventory randomly selected samples for future PLT testing requirements. 

EMA commented on §1054.610(c)(12) “What is the exemption for delegated final 

assembly?” EMA commented that this section should be revised in order to clarify that engine 

manufacturers may inventory equipment manufacturer supplied exhaust systems for production 

line testing, provided that such systems are randomly selected components that are representative 

of equipment manufacturer production. 

Class I engines: 

OPEI and EMA commented that Class I engines are generally sold complete with the 

engine manufacturer supplied exhaust system. However, there are a limited number of specialty 

products where this is not possible. Some Class I products have all of the same equipment 

manufacturer/customer demands that are necessary to provide a Delegated Assembly option for 

the larger Class II engines. OPEI and EMA commented that these Class I products should not be 

precluded from this required flexibility based only on their respective class. 

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Liability: 

EMA commented that engine manufacturers utilizing the delegated assembly provisions 

and meeting all specified requirements (e.g., provide the equipment manufacturer with all 

information necessary to complete the engine assembly to it’s certified configuration, and 

conduct the required audits) must be assured that the equipment manufacturer is responsible for 

delivering compliant product into commerce. 

Honda noted that the NPRM takes the position that the engine manufacturer, as the 

engine certifying party, becomes responsible for the actions of the equipment manufacturer, an 

independent business. The NPRM essentially appoints the engine manufacturer to be the 

“Selective Enforcement Authority” and to perform audits of the equipment manufacturer as 

though the engine manufacturer were a government agency with authority to enter a business and 

inspect records. Honda does not believe EPA intends to relinquish its independent enforcement 

authority nor does Honda believe it is reasonable to ask the equipment manufacturer to submit, 

by contract or otherwise, to inspection by competing engine manufacturers, all of whom sell to 

his competitors, and in some instances produce the same type of product within their own 

company or a wholly owned subsidiary. Honda also noted that the NPRM states that the 

equipment manufacturer must follow the engine manufacturer’s instruction or the equipment is 

not covered by the certificate of conformity and not legal to introduce into commerce. 

Air filters: 

EMA commented on §1054.610(e) “What is the exemption for delegated final 

assembly?” EMA commented that manufacturers must have the ability to certify engines 

without identifying a specific part number for the air filter. This ability must either be 

specifically incorporated into the regulatory language, or included in a clarifying regulatory 

support document. Current Certification Guidance and submission templates require inclusion of 

air filter part numbers as a condition of certification. However, this section would allow engine 

manufacturers to provide a definitive parameter, such as intake restriction range, to define the 

certified configuration. Therefore, equipment manufacturer installed intake systems meeting the 

engine manufacturer prescribed parameter would not be subject to these provisions. 

References: 

EMA commented on §1054.610(g)(2) “What is the exemption for delegated final 

assembly?” EMA commented that §1054.610(g)(2) includes an incorrect reference to paragraph 

(g)(2). This reference should be corrected to refer to paragraph (g)(1). 

Within-company shipments: 

EMA commented on §1054.610(m) “What is the exemption for delegated final 

assembly?” EMA noted that as set forth in §1054.610(d), engine manufacturers that install 

engines into equipment are not required to request an exemption or take any other extraordinary 

steps in order to do so. Likewise, engine manufacturers should be allowed to complete 

production of engines at different facilities without being required to request an exemption. 

Accordingly, EMA commented that this section should be deleted. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Evaporative systems: 

EMA commented on §1054.610 “What is the exemption for delegated final assembly?” 

EMA commented that this section should be revised to add a provision similar to §1054.610(c) 

that would apply to the situation where an engine manufacturer certifies compliance to the 

evaporative standards and delegates final assembly of the evaporative system to the equipment 

manufacturer. Such a provision is of particular importance to small equipment manufacturers 

that cannot use fully integrated engines and do not have the resources to design and certify 

pursuant to the 40 CFR Part 1060 requirements. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

EMA 0691 

Honda 0705 

Our Response: 

General: 

As noted in the proposal and in the comments, we have already adopted delegatedassembly provisions for heavy-duty highway engines in part 85 and for nonroad engines in part 

1068 in addition to what we proposed for Small SI engines in part 1054. We have made a 

comprehensive review of these various regulations to create a hybrid program that allows us to 

take what we believe is a robust approach that uniformly and broadly addresses the concerns 

related to the cooperative efforts of engine, equipment, and component manufacturers in 

designing and assembling certified systems. The combined approach, which incorporates 

elements of each of the three programs, is written in a new §1068.261. There is also an 

abbreviated version of §1068.260 remaining to describe a framework and general provisions 

related to the arrangements between engine and equipment manufacturers in taking engines 

through the assembly process to reach a certified configuration. Section 1.xx describes the 

approach we took to creating this unified program. The rest of this section describes how the 

final program differs from the proposal and responds to the specific concerns related to Small SI 

engines and equipment raised in the comments. 

There are three principal differences between the proposed and final regulations for Small 

SI engines and equipment. First, we are allowing distributors to participate in delegated 

assembly, but distributors would need to act as equipment manufacturers, adding catalyzed 

mufflers where appropriate for shipment to equipment manufacturers. We proposed to allow 

distributors to act as agents on behalf of engine manufacturers to further delegate assembly to 

equipment manufacturers. We are allowing this only for the first four years of the Phase 3 

standards (2011 through 2014 model years). While a more flexible approach is needed for the 

transition to new standards, as described above, we believe this is not appropriate for the long 

term because of concerns about the ability of engine manufacturers to ensure that engines will be 

assembled in the certified configuration. As described in the comments, assembling engines 

involves a very significant effort to differentiate different models and manage engines and 

components coming from multiple suppliers. We believe that there is too much risk of 

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miscommunication or misbehavior where a distributor is acting on behalf of the engine 

manufacturer to do design work, arrange for shipment, and manage audits and other oversight 

steps to ensure that potentially large numbers of very small equipment manufacturers properly 

assemble engines. Given the complexity and diversity of these arrangements, we expect that the 

question would be how extensive the noncompliance is, not whether there would be 

noncompliant engines. Such problems would be difficult to find and, if we do discover a 

problem, it would be difficult to hold any particular company accountable, given the distribution 

of responsibility among the several companies. Nevertheless, we expect to learn a lot from the 

experience of implementing these provisions. If we see that manufacturers can observe the 

regulatory requirements in a way that alleviates the concerns described here, we would be open 

to a regulatory amendment to continue the provisions related to distributors that we are adopting 

on an interim basis. 

We understand that some companies will be too small to get an engine manufacturer to 

agree to participate in delegated assembly for some or all of their equipment models. In these 

cases, we believe distributors will in many cases be able to provide design support for the 

equipment manufacturer. Small equipment manufacturers could benefit from a distributors 

ability to participate in delegated assembly, but only to the extent that the distributor can 

coordinate muffler designs with the muffler manufacturer, the engine manufacturer, and the 

equipment manufacturer. Distributors often serve an important role in helping small equipment 

manufacturers with system integration to properly install engines and to maximize the 

performance of the equipment to match the engine’s design parameters and specifications. 

Allowing distributors to participate in delegated assembly would be a natural fit with this role. 

We also recognize that some equipment manufacturers would have such small volumes or 

distinct equipment parameters t that they would not benefit from this limited role of distributors 

in delegated assembly. As a result, these companies would need to redesign their equipment as 

needed to be able to use one of the stock muffler configurations available from the engine 

manufacturer or distributor. As noted above, we believe this is achievable by the time the 

transition provisions expire in 2015. 

Second, the final rule requires that audits minimally involve inspection of assembly 

procedures and production records, investigation of assembled engines, and confirmation that the 

number of aftertreatment devices shipped were sufficient for the number of engines produced. 

The proposal specified that an audit could include any one of these three things. As described 

above, we are concerned that insufficient oversight would lead to a situation where equipment 

manufacturers assemble engines such that they are not in their certified configuration, either as a 

simple mistake or to take advantage of the discretion allowed to get away with changes that 

reduce costs or change design parameters for some performance advantage. We believe the three 

activities noted are basic steps that should be part of any audit. Moreover, we specifically 

identify these as minimum steps for performing an effective audit. If we learn over time that 

these steps are insufficient, either for specific manufacturers or the industry as a whole, we may 

require additional auditing steps to ensure that engines are properly assembled. 

A current enforcement case highlights the need for active oversight with delegated 

assembly. An engine manufacturer has been relying on installation instructions to ensure that 

equipment manufacturers install the proper air filter, which is identified specifically by part 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

number in the application for certification. It turns out that an equipment manufacturer was 

found to be substituting a different air filter for some perceived advantage, either for cost or 

performance, which caused the engines to be sold in an uncertified configuration. The engine 

manufacturer had taken steps to make the information available to equipment manufacturers, but 

this was clearly not enough to ensure that final assemblies involved only engines in a certified 

configuration. In anticipation of engines using catalyzed mufflers, we see the incentive for 

departing from an engine manufacturer’s installation instructions only increasing. We therefore 

believe that delegated assembly can be successfully done only with an active program to oversee 

and document compliance with installation instructions. 

Third, we specify a different schedule for the number of audits that engine manufacturers 

must perform after the first four years. In fact, the change involves a smaller number of audits, 

based on our expectation that a smaller number of equipment manufacturers will be participating 

in delegated assembly after the transition to the Phase 3 standards is complete. 

The following paragraphs respond to the individual concerns expressed in the comments. 

Written confirmation: OPEI’s suggestion is consistent with our proposal. The final 

rule preserves this provision, not only for small businesses but for all companies. 

We believe this requirement is quite clear and viable, reflecting the need for confirmation 

with the business realities of ordering and shipping engines. In particular, we believe it is not 

sufficient for equipment manufacturers to satisfy the requirement for written confirmation simply 

by notifying the engine manufacturer that they are aware of the regulatory requirements. This 

requirement is in the context of a scenario in which the equipment manufacturer is separately 

procuring and paying for aftertreatment devices. There is a substantial risk for engine 

manufacturers to send out noncompliant products without this assurance, so we believe engine 

manufacturers would want to treat the regulatory requirement as a minimum for ensuring that 

their engines do not reach ultimate purchasers in an noncompliant configuration. 

Audits: In a situation where delegated assembly does not require engine manufacturers to 

include the price of aftertreatment with the price of the engine, we are concerned that there is too 

great an incentive for equipment manufacturers to deviate from the specified installation 

instructions, either to reduce costs or to gain some perceived performance advantage. As 

described above, we believe an effective audit that minimally includes the three elements 

specified under the current regulations in §1068.260 is essential for maintaining proper oversight 

of the assembly process. The application for certification should include enough information to 

make clear that the certifying engine manufacturer will properly fulfill its auditing 

responsibilities. 

We believe it is appropriate for engine manufacturers to follow an auditing plan that 

involves reasonably objective directions for selecting equipment manufacturers. Adding “as 

much as possible” to this direction would make it meaningless. As noted by EMA, certain 

equipment manufacturers will have earned more or less confidence based on their relationship 

with the engine manufacturer and their past performance. Allowing engine manufacturers more 

discretion in this regard would only allow them to delay auditing equipment manufacturers for 

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which there is less confidence that everything is in order. If engine manufacturers are 

particularly concerned about any one equipment manufacturer, they should be sure to audit that 

company independent of the specific regulatory requirements, or simply terminate the 

arrangement for that company. 

Point of final assembly: We specified in the proposal that the exemption expires at the 

point of final assembly because there is a need to avoid a situation in which a delegatedassembly engine is introduced into commerce in an uncertified configuration where we would 

not want to consider that a violation. The exemption therefore covers a shipment from the 

engine manufacturer to the equipment manufacturer (or from one of the equipment 

manufacturer’s facilities to another). There is no need for an exemption for other internal 

processes after the equipment reaches the point of final assembly, because its engine needs to be 

in a certified configuration the next time it is introduced into commerce. There is no violation 

for an engine that is placed into inventory at the end of the assembly line and then pulled back 

for trading out exhaust components to be in a different certified configuration. Note however, 

that if an EPA inspection of an equipment manufacturer’s inventory of completed products turns 

up engines that are not in a certified configuration, we would take steps to address the 

nonconformity, as allowed under the regulations. 

Label: We agree that abbreviating “Delegated Assembly” may be appropriate, so we are 

revising the regulation to allow labels with “DEL ASSY” where space prevents the full 

designation. Especially with the approach we are taking for labeling with respect to evaporative 

emission families, further abbreviating the term would only be confusing or inappropriate. 

The proposed rule included labeling requirements consistent with CARB’s second 

recommended option. We are adopting similar labeling requirements for the final rule, including 

the option of either applying a temporary label or identifying “delegated assembly” on the 

permanent label. This ensures that the engine will be properly identified at every point in the 

assembly (and shipping) process. We believe equipment manufacturers should not be 

responsible for labeling engines where they are simply assembling the exhaust system. 

Production-line testing: We agree that manufacturers should be able to maintain an 

inventory of randomly selected components for testing. We have revised the regulations 

accordingly. 

Class I engines: We agree that engine manufacturers may need to use the delegatedassembly provisions for Class I engines, though this should be far less common than for Class II 

engines. We are therefore preserving this provision in the final rule. 

Liability: The regulations appropriately state that engine manufacturers are liable for the 

in-use compliance of every certified engine. The delegated-assembly provisions are an option 

that engine manufacturers may exercise based on their business interests and their relationships 

with equipment manufacturers. Choosing to use these provisions does not change the 

fundamental responsibility associated with certifying engines, to ensure that engines comply with 

the regulations throughout the useful life. In addition, the regulations also make clear that 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

equipment manufacturers are in violation if they introduce equipment into commerce without 

following the engine manufacturer’s installation instructions. 

If an equipment manufacturer has been found to be in violation, we specify that we may 

require the engine manufacturer to discontinue the use of delegated assembly for that 

manufacturer (revoking the exemption). We would generally not hold engine manufacturers 

responsible for noncompliant engines where the equipment manufacturer is fully responsible for 

the noncompliance. However, we would hold engine manufacturers in violation if they 

intentionally submitted false or incomplete information (voiding the exemption). 

Honda correctly notes that we are not surrendering our enforcement authority with 

respect to delegated assembly. However, we have described our basis for being concerned that 

engine manufacturers do more than simply send incomplete engines with installation 

instructions, trusting equipment manufacturers to properly complete engine assembly subject to 

EPA’s enforcement of applicable requirements. Delegated assembly is fully optional, so any 

engine or equipment manufacturers not wanting to be subject to the required oversight functions, 

or not wanting to be in a situation where confidential business information would be 

compromised, may choose not to participate in delegated assembly. Engine manufacturers could 

also take the middle ground, participating in delegated assembly but including the price of 

aftertreatment in the price of the engine. In this case, the regulations specify a significantly 

lighter oversight burden. Since the engine manufacturer is choosing to participate in delegated 

assembly, it is unclear why there would be any thought that they should take steps to ensure that 

engines are assembled properly. Third-party auditors could do on-site visits if there is a 

sensitivity regarding access to a competitor’s facilities or records. Moreover, we specifically 

state in the regulation that information submitted between companies under these regulatory 

provisions is considered to have been equivalent to a submission to EPA. The prohibitions in 

§1068.101 and the corresponding civil and criminal penalties apply for any false information that 

a company submits to another company. 

Air filters: The regulations include the clarifying language requested by EMA in which 

we specify that air filters are subject to the delegated-assembly requirements only if the 

manufacturer’s certification depends on identifying the air filter by part number. In contrast, if 

the manufacturer certifies an engine based on specified intake restrictions, the delegatedassembly provisions do not apply. In this scenario, the engine manufacturer would still be 

responsible for the in-use compliance of any engines in the engine family that were assembled 

following the applicable installation instructions. 

References: We have revised the regulations such that this reference is obsolete. 

Within-company shipments: The final regulations include the streamlined provisions 

for engine manufacturers that also manufacture equipment and install their own engines. 

Deleting the provisions related to completing production at different facilities would 

disallow this practice entirely. We need to be aware of this practice and to be able to set 

conditions or require specific steps to ensure that the exemption is not abused. We therefore 

need to base this exemption on EPA approval; however, we specify that the manufacturer must 

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simply describe this practice in the application for certification. Approving the certification is 

considered approval of the exemption. We are therefore retaining this provision as proposed. 

Evaporative systems: Engine manufacturers must comply with evaporative emission 

standards to the extent they assemble fuel-system components. They are not responsible for 

further assembly of the fuel system by equipment manufacturers so there is no need for an 

exemption or other provisions analogous to delegated assembly. 

2.9 Equipment manufacturer recertification 

What Commenters Said: 

OPEI supported EPA’s proposal to allow the re-certifying equipment manufacturers to: 

1) only conduct low-hour emission testing on the “green” modified exhaust system; and 2) rely 

on and apply the engine manufacturer’s previously established deterioration factors. OPEI 

commented that EPA has also appropriately proposed not to apply PLT testing to the recertifying OEM as this would overly-complicate this process without any benefits since the 

engine would already be subject to PLT. OPEI commented that this re-certification provision 

should be permanent and not expire. OEMs will still require muffler certifications on a longterm basis to produce certain critical equipment models. 

 Regarding equipment manufacturer recertification, CARB believes that such a provision 

would conflict with anti-tampering regulations. CARB commented that an alternative would be 

the equipment manufacturer working with the engine manufacturer (holder of the executive 

order) to include his/her variation as a running change and re-testing for a new worst-case 

model/configuration. However, if EPA does adopt the provision to allow equipment 

manufacturer recertification, CARB commented that EPA should require production line testing 

and impose an expiration date for the program. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

Our Response: 

 We agree that there may be a continuing need for equipment manufacturers to rely on the 

streamlined certification proposed in §1054.612 where they rely on a catalyst from an alreadycertified engine family. The streamlined certification would allow the equipment manufacturer 

to assemble that catalyst in a custom muffler configuration. We believe this situation calls for a 

reduced certification burden, especially for developing deterioration factors. 

We also believe that there will be a reduced need for this as time passes. As described 

above, the four-year transition program should allow time for engine and equipment 

manufacturers to work out arrangements for designing and producing mufflers in compliant 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

configurations. As a result, we believe it is appropriate to limit the provisions for streamlined 

certification starting in 2015. In discussion with manufacturers, there was general agreement 

that an appropriate threshold would be annual sales of 5,000 units, which is already established 

as the threshold for defining small-volume engine families. 

There is no violation of the tampering prohibition because the engine would never be 

introduced into U.S. commerce in an uncertified configuration. 

We agree that changes coming in response to an equipment manufacturer’s needs could 

be factored in as a running change for the certifying engine manufacturer (with new testing as 

needed). This would require no new regulatory provisions; however, the proposed approach 

addresses the situation where the engine manufacturer does not want to be responsible for the 

changes called for by the equipment manufacturer. 

We will monitor the use of this provision over time, both for its frequency of use and the 

degree of compliance. We may choose to discontinue the streamlined recertification provisions 

in the future, but we believe there is enough chance that equipment manufacturers will depend on 

it that it can be appropriately applied beyond 2014 for small-volume emission families as 

described above. 

2.10 Compliance provisions 

2.10.1 Warranty assurance 

What Commenters Said: 

OPEI and EMA noted that the proposal implements a change in the requirements for 

manufacturers to provide emission warranty service including provisions that deal with people 

living more than 100 miles from an authorized service center starting in 2009 model year. OPEI 

and EMA understand the agency’s concern that customers must have access to sources of 

emission warranty but they do not support the prescriptive solution associated with authorized 

service centers within 100 miles of every customer. It will be virtually impossible for engine or 

equipment manufacturers to identify where the ultimate purchaser of a piece of equipment may 

use the equipment and therefore impossible to properly identify for the agency that the 

requirement has been met. The relief purported to be provided regarding sparsely populated 

areas is also not viable. If any provision is required beyond the need for at least one distributor 

within the United States, OPEI and EMA recommended that the servicing dealer requirement be 

linked to population centers with a 2000 U.S. Census population in excess of 100,000 people. 

(See §90.1103 Emission warranty, warranty period and §1054.120(f)(3) and (4) What emissionrelated warranty requirements apply to me?) 

CARB supported EPA’s “Special Provisions for Compliance Assurance,” and 

specifically supported the provisions regarding the assurance of warranty coverage. 

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Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

EMA 0691 

Our Response: 

 Certifying manufacturers must not only sell a product that meets emission standards, but 

also meet obligations over a defined period of service. The most obvious requirements related to 

in-use engines are warranty and recall. We are aware that many low-cost engines are sold by 

foreign manufacturers with little or no presence in the U.S. market for honoring warranty claims. 

This is a violation of the regulations, subject to substantial penalties. We believe it is very 

important to take the preventive step at certification to have companies describe their plan for 

meeting warranty obligations than to wait until there is a violation. The proposed approach was 

an attempt to reasonably balance a consumer’s need to be able to access an authorized service 

center with the manufacturer’s burden to maximize coverage with their repair facilities. 

We believe it is clearly necessary to require more than a single parts distributor in the 

United States to expect a manufacturer to be able to provide effective warranty coverage for 

consumers. We agree with the approach recommended by the manufacturers to say that they can 

demonstrate adequate warranty coverage by placing authorized service centers in all U.S. 

population centers with a census count of 100,000 or more. Table 2-1 identifies 251 areas from 

the 2000 census that qualify, listed alphabetically by state. We have modified the regulations to 

allow for this demonstration. 

We are also aware that some companies may not sell engines throughout the United 

States, in which case they would not be expected to maintain authorized service centers in all the 

identified population centers. We are keeping a modified version of the proposed requirement 

as an alternative to the commenters’ suggestion to rely on the list of population centers. This 

would allow manufacturers to choose from a variety of methods for demonstrating an ability to 

respond to warranty claims. 

 We are adopting two main changes to the proposed approach related to warranty 

demonstrations. First, we are clarifying that the distance from consumers is based only on the 

contiguous United States. This allows us to avoid an expectation that manufacturers maintain 

multiple service centers across Alaska or in every U.S. territory. Second, we are revising the 

provisions related to sparsely populated areas. While the proposal allowed for up to 10 percent 

of sales to be to owners living more than 100 miles from an authorized service center, we agree 

that this would be difficult for manufacturers to implement. We are instead specifying that the 

100-mile limit does not apply in states with any high-altitude areas (see 40 CFR part 1068, 

Appendix III). Identifying states with high-altitude areas aligns quite closely with low 

population density. 

To the extent that the 100-mile approach or the population centers doesn’t fit well 

nationwide for a given manufacturer, we would also allow for a combined approach in which the 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

manufacturer would rely on one method for certain states and another method for other states. 

However, we would require each state to have at least one authorized service center unless the 

manufacturer is able to meet the 100-mile specification without having an authorized service 

center in a given state. 

Also, we proposed to apply these requirements in the 2009 model year, but we believe 

the timing of the final rule dictates that we allow an additional year for manufacturers to meet 

these new requirements. We have therefore modified the regulations to require manufacturers to 

comply starting with the 2010 model year. 

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Table 2-1 

U.S. Population Centers over 100,000 – U.S. Census, 2000* 

Birmingham, AL 

Huntsville, AL 

Mobile, AL 

Montgomery, AL 

Anchorage, AK 

Chandler, AZ 

Gilbert, AZ 

Glendale, AZ 

Mesa, AZ 

Peoria, AZ 

Phoenix, AZ 

Scottsdale, AZ 

Tempe, AZ 

Tucson, AZ 

Little Rock, AR 

Anaheim, CA 

Antioch, CA 

Bakersfield, CA 

Berkeley, CA 

Burbank, CA 

Chula Vista, CA 

Concord, CA 

Corona, CA 

Costa Mesa, CA 

Daly City, CA 

Downey, CA 

El Monte, CA 

Elk Grove, CA 

Escondido, CA 

Fairfield, CA 

Fontana, CA 

Fremont, CA 

Fresno, CA 

Fullerton, CA 

Garden Grove, CA 

Glendale, CA 

Hayward, CA 

Huntington Beach, CA 

Inglewood, CA 

Irvine, CA 

Lancaster, CA 

Long Beach, CA 

Los Angeles, CA 

Modesto, CA 

Moreno Valley, CA 

Norwalk, CA 

Oakland, CA 

Oceanside, CA 

Ontario, CA 

Orange, CA 

Oxnard, CA 

Palmdale, CA 

Pasadena, CA 

Pomona, CA 

Rancho Cucamonga, CA 

Richmond, CA 

Riverside, CA 

Roseville, CA 

Sacramento, CA 

Salinas, CA 

San Bernardino, CA 

San Buenaventura (Ventura), CA 

San Diego, CA 

San Francisco, CA 

San Jose, CA 

Santa Ana, CA 

Santa Clara, CA 

Santa Clarita, CA 

Santa Rosa, CA 

Simi Valley, CA 

Stockton, CA 

Sunnyvale, CA 

Thousand Oaks, CA 

Torrance, CA 

Vallejo, CA 

Visalia, CA 

West Covina, CA 

Arvada, CO 

Aurora, CO 

Colorado Springs, CO 

Denver, CO 

Fort Collins, CO 

Lakewood, CO 

Pueblo, CO 

Thornton, CO 

Westminster, CO 

Bridgeport, CT 

Hartford, CT 

New Haven, CT 

Stamford, CT 

Waterbury, CT 

Washington, DC 

Cape Coral, FL 

Clearwater, FL 

Coral Springs, FL 

Fort Lauderdale, FL 

Gainesville, FL 

Hialeah, FL 

Hollywood, FL 

Jacksonville, FL 

Miami, FL 

Miami Gardens, FL 

Miramar, FL 

Orlando, FL 

Pembroke Pines, FL 

Port St. Lucie, FL 

St. Petersburg, FL 

Tallahassee, FL 

Tampa, FL 

Athens-Clarke County, GA 

Atlanta, GA 

Augusta-Richmond County, GA 

Columbus, GA 

Savannah, GA 

Honolulu, HI 

Boise City, ID 

Aurora, IL 

Chicago, IL 

Joliet, IL 

Naperville, IL 

Peoria, IL 

Rockford, IL 

Springfield, IL 

Evansville, IN 

Fort Wayne, IN 

Indianapolis, IN 

South Bend, IN 

Cedar Rapids, IA 

Des Moines, IA 

Kansas City, KS 

Olathe, KS 

Overland Park, KS 

Topeka, KS 

Wichita, KS 

Lexington-Fayette, KY 

Louisville-Jefferson County, KY 

Baton Rouge, LA 

Lafayette, LA 

New Orleans, LA 

Shreveport, LA 

Baltimore, MD 

Boston, MA 

Cambridge, MA 

Lowell, MA 

Springfield, MA 

Worcester, MA 

Ann Arbor, MI 

Detroit, MI 

Flint, MI 

Grand Rapids, MI 

Lansing, MI 

Sterling Heights, MI 

Warren, MI 

Minneapolis, MN 

St. Paul, MN 

Jackson, MS 

Independence, MO 

Kansas City, MO 

Springfield, MO 

St. Louis, MO 

Lincoln, NE 

Omaha, NE 

Henderson, NV 

Las Vegas, NV 

North Las Vegas, NV 

Reno, NV 

Manchester, NH 

Elizabeth, NJ 

Jersey City, NJ 

Newark, NJ 

Paterson, NJ 

Albuquerque, NM 

Buffalo, NY 

New York, NY 

Rochester, NY 

Syracuse, NY 

Yonkers, NY 

Cary, NC 

Charlotte, NC 

Durham, NC 

Fayetteville, NC 

Greensboro, NC 

Raleigh, NC 

Winston-Salem, NC 

Akron, OH 

Cincinnati, OH 

Cleveland, OH 

Columbus, OH 

Dayton, OH 

Toledo, OH 

Norman, OK 

Oklahoma City, OK 

Tulsa, OK 

Eugene, OR 

Portland, OR 

Salem, OR 

Allentown, PA 

Erie, PA 

Philadelphia, PA 

Pittsburgh, PA 

Providence, RI 

Charleston, SC 

Columbia, SC 

Sioux Falls, SD 

Chattanooga, TN 

Clarksville, TN 

Knoxville, TN 

Memphis, TN 

Nashville-Davidson, TN 

Abilene, TX 

Amarillo, TX 

Arlington, TX 

Austin, TX 

Beaumont, TX 

Brownsville, TX 

Carrollton, TX 

Corpus Christi, TX 

Dallas, TX 

El Paso, TX 

Fort Worth, TX 

Garland, TX 

Grand Prairie, TX 

Houston, TX 

Irving, TX 

Laredo, TX 

Lubbock, TX 

McAllen, TX 

Mesquite, TX 

Pasadena, TX 

Plano, TX 

San Antonio, TX 

Waco, TX 

Wichita Falls, TX 

Salt Lake City, UT 

West Valley City, UT 

Alexandria, VA 

Arlington CDP 

Chesapeake, VA 

Hampton, VA 

Newport News, VA 

Norfolk, VA 

Richmond, VA 

Virginia Beach, VA 

Bellevue, WA 

Seattle, WA 

Spokane, WA 

Tacoma, WA 

Vancouver, WA 

Green Bay, WI 

Madison, WI 

Milwaukee, WI 

*Source: U.S. Census Bureau (see http://www.demographia.com/db-usmuni2004.htm) 

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2.10.2 Bonding 

What Commenters Said: 

OPEI noted that its members are facing an enormous threat from manufacturers of noncompliant engines – particularly as the costs increase to produce even cleaner, EPA-compliant 

products. The current EPA framework is not designed with the safeguards needed to address the 

imminent threat from "bad actors" with no U.S. assets. Certain off-shore manufacturers have 

become very sophisticated in relying on "shell importers” in order to avoid any meaningful 

enforcement exposure. 

OPEI commented that the final Phase 3 small engine regulations should require a foreign 

manufacturer (that has no U.S. assets) to post a bond to cover a portion of his engines in case 

they do not comply with the EPA emission standards. These bonding requirements are really the 

only meaningful mechanism EPA has to take action against a "bad foreign actor" who sells noncompliant engines through a "shell importer" and disappears if his non-compliant products are 

discovered. OPEI therefore supported EPA’s proposed bonding requirements for foreign 

manufacturers and importers with no U.S. assets to create an even and effective compliance and 

enforcement program. OPEI urged EPA to pull ahead and make effective in 2007 the bonding 

requirements. 

OPEI commented that it does not believe it would be necessary or appropriate to impose 

such bonds on established manufacturers that have adequate U.S. assets to cover non-compliance 

events. Even with EPA’s new proposed, bonding requirements, manufacturers with substantial 

U.S. assets will still have dramatically greater compliance exposure (and incur greater costs) than 

a foreign manufacturer which just submits a bond. 

OPEI commented that there should not be any other exemptions from the bonding 

requirements given the difficulty in defining an objective and practical criterion for preventing 

enforcement abuses. OPEI is skeptical that EPA can develop clear and objective regulatory 

language that would establish an exemption to the bonds for manufacturers that have a 

demonstrated long-term record of no violations. Moreover, OPEI is concerned that many 

manufacturers have previously certified engines, but not shipped any products into the U.S. 

market. Thus, the fact there has not been a known prior violation does not really indicate that 

such a manufacturer is a “responsible” company. OPEI also does not believe EPA will be able to 

establish clear and objective standards to exempt from the bonding requirements either 

manufacturers or importers who had been certified to voluntary industry standards for production 

quality (such standards do not currently exist) or who performed voluntary in-use testing. 

Deliberate “bad actors” intent on circumventing the regulations will be willing to also fabricate 

their compliance with production quality standards or voluntary in-use testing. 

Euromot commented that, as importers, they accept the bonding requirements (or 

equivalent U.S. assets) and concept of a stronger market surveillance option within the proposed 

regulation. 

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CARB commented that it supports U.S. EPA’s “Special Provisions for Compliance 

Assurance,” and specifically supports the provisions regarding importation data, the assurance of 

warranty coverage, and bond requirements. The posting of bonds to cover compliance or 

enforcement-related obligations for importers who have not yet proven financial stability is 

crucial. Without the bonds, consumers may not be able to obtain needed warranty coverage. 

Also, if the imported engines are found not to meet the standards then enforcement actions can 

be made using the bond funds. Once a company gets into good financial standing, determined 

by EPA, then the company can be refunded the bond funds. Overall, CARB agreed with EPA 

that a bond requirement is necessary. However, CARB asked that in the proposed regulatory 

language EPA not preclude California from adopting a similar program should CARB deem it 

appropriate in the future for California certified engines. 

Briggs & Stratton commented that it supports the bonding requirements in the NPRM. It 

is imperative for the small engine industry that all manufacturers are accountable for meeting the 

emission regulations, not just those located in the U.S. who are therefore susceptible to EPA 

enforcement actions. Companies with U.S. assets sufficient to cover enforcement actions should 

not be required to post import bonds, but companies without such U.S. assets should post bonds 

to ensure uniform enforcement for all manufacturers. 

EMA supported the bonding requirements set forth in the NPRM. Such requirements are 

an important step to creating a level playing field among all competitors. Engine manufacturers 

that do not have sufficient assets in the United States to avoid the bonding requirement also are 

unlikely to have adequate resources in the U.S. to audit equipment manufacturer use of the 

delegated assembly provisions. Manufacturers that have significant physical assets in the United 

States can easily be identified, and EPA can take appropriate legal action as required when/if 

there is a compliance concern. EPA does not have access to manufacturers without assets in the 

United States, making it difficult, if not impossible, to take enforcement action against such 

entities. EMA commented that the proposed bonding provision correctly requires all parties 

responsible for compliance with the Phase 3 regulations to have assets in the U.S. (whether 

physical assets, or a posted bond) that may be attached in connection with an enforcement action. 

If the proposed bonding provisions are not adopted, EMA commented that it is imperative that 

EPA adopt another means to ensure that it has the ability to take enforcement action against 

manufacturers that do not have assets located in the United States. In addition, the enforcement 

provisions associated with Part 1054 and Part 1060 apply to any party that introduces product 

into commerce in the United States and EPA should exercise its authority accordingly. 

EMA commented on §1054.690 “What are the bond requirements for importing certified 

engines and equipment?” EMA commented that the last part of the last sentence in paragraph (a) 

does not make sense as drafted. Accordingly, EMA suggested that the sentence should be 

revised to read as follows (new language is in italics): “For example, it would be a sufficient 

demonstration if you show that you have manufactured or imported engines for the U.S. market 

for a significant period of time without failing a test conducted by EPA officials or being found 

to be substantially not in compliance with EPA regulations.” 

The National Association of State Fire Marshals commented that their preliminary review 

suggests that the Chinese are capable of making a significant impact on the United States market. 

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They noted that they have seen this before, with Chinese manufactured All-Terrain Vehicles 

(ATVs) capturing over 30% of the U.S. market in just a few years. ATV's which they have 

tested, and provided to CPSC, failed to meet the applicable American National Standard and they 

recommended that they be recalled. 

The National Association of State Fire Marshals commented that EPA's proposed Phase 3 

Certification and compliance provisions are well suited for the legacy engine and equipment 

manufacturers that have an established track record for meeting EPA's Phase 2 requirements. 

They noted that EPA recognized the concerns with imported products, and their plans are 

noteworthy. However, new entrants from China can be expected to defy these provisions. Their 

experience enforcing CPSC regulations has shown that Chinese manufacturers and importers are 

willing to falsify conformance with CPSC regulations and to “port shop” until entry into the 

United States is achieved. 

Letters: 

Commenter Document # 

OPEI 0675 

CARB 0682 

Euromot 0649 

Briggs and Stratton 0657 

EMA 0691 

National Association of State Fire Marshals 0673 

Our Response: 

We agree with the comments noting the need for bonding provisions to ensure that 

companies without substantial U.S. assets should be subject to bonding requirements to ensure 

enforcement with their obligations associated with certifying engines. Bond payments would 

allow EPA to compel companies to take actions or pay penalties where there might otherwise be 

no way of enforcing regulatory requirements. The bond payment would not apply for companies 

with substantial physical assets in the United States, since they are inherently subject to EPA’s 

enforcement of regulatory requirements because we have access to the company’s personnel and 

facilities to compel compliance or payment of penalties. 

We also note that bonds are generally not paid in a lump sum and then refunded after 

some period. Rather, companies pay a premium to a bond agent who then opens a policy or 

account with a face value equal to the amount of the bond obligation, much like an insurance 

policy. Any EPA judgments against the company would generally be paid by the bond agent out 

of the account. As a result, the expense for maintaining a bond is simply the regular premium for 

maintaining a valid bond. 

We are not including in the regulation any provision that would preclude California from 

adopting its own requirements for bond payments. However, any bond requirements in 

California would need to conform with any prevailing legal authority related to international 

trade. 

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We believe that basing bond payments on adherence to industry standards such as ISO 

14000 would not be effective in assigning bond responsibilities where that would be necessary or 

appropriate, as described in the comments. We also believe it would not be appropriate to 

simply waive bond requirements based on some measure of compliance history, though we are 

prepared to set a lower threshold as an asset test as described below. 

In discussions following the end of the comment period, manufacturers made three 

recommendations regarding the implementation of a bond requirement. First, they pointed out 

that there should be a minimum bond value rather than relying only on the published per-engine 

bond values. This would prevent small-volume importers from being responsible for 

maintaining a bond whose value is too small to provide any reasonable assurance of compliance 

or any practical ability to cover possible financial judgments if the company or its products are 

found to be in violation. We believe it would be necessary to require a bond value of $250,000 if 

the calculated value based on a per-engine calculation is less than that. This would ensure that 

the bond would cover a violation involving eight engines (or eight days where penalties are 

calculated per day). We believe any smaller bond value would be insufficient to achieve the 

objectives described above. 

Second, manufacturers suggested $10 million of physical assets as a threshold value for 

determining whether a company has enough of a presence in the United States to avoid a bond 

payment. This would include any property to which the company possesses a clear title. The 

value of any given property should be based on a commercial appraisal. A mortgage or other 

debt obligation associated with the property would not affect the value with respect to 

determining whether bond requirements apply. We believe a $10 million threshold is high 

enough to avoid a situation where foreign manufacturers can make a token property investment 

to avoid bond payments, without imposing bond obligations on companies that have sufficient 

assets for demonstrating an ability to meet compliance and enforcement obligations. However, 

we believe smaller amounts would be appropriate for secondary engine manufacturers, where the 

capital investment for a given level of engine production may be much smaller as a result of the 

business practice of buying engines that are already nearly complete. We therefore believe $6 

million is an appropriate threshold for secondary engine manufacturers. Also, we are aware that 

there is a reduced need for bond payments where companies have a consistent record of meeting 

their certification and compliance obligations. As such, we believe a reduced threshold of $3 

million in U.S.-based assets is appropriate for companies that have certified for the previous ten 

years without being found in noncompliance. 

Third, manufacturers pointed out that the bond payment should not be a condition of 

certification. We agree that manufacturers should not be required to post a bond before they 

certify their engines. However, we believe it is necessary for companies to describe in the 

application for certification why they should be exempt from the bonding requirements, if 

applicable. This would allow us to take any appropriate steps to verify claimed assets before 

importation, rather than trying to correct a problem after a violation occurs. If bond payments 

are required for a given manufacturer, the bond would need to be in place for any 2010 model 

year engines introduced into U.S. commerce on or after January 1, 2010. 

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2.10.3 Restricted model year 

What Commenters Said: 

Regarding restrictions related to naming model years, CARB commented that it believes 

it is reasonable to require that model year engines and equipment may be at most one year earlier 

than the calendar year of the importation during the change of the emission standards. 

Whichever requirements EPA chooses to adopt, CARB recommended that procedures be 

adopted to prevent any stockpiling of engines that could be used to circumvent the regulations. 

EMA commented that the proposal’s requirement that imported engines be identified by 

either model year of importation or one model year earlier is a viable and appropriate approach 

to preventing the stockpiling of older engines/equipment. However, given the seasonal nature of 

lawn and garden products, there are limited situations where the one year limitation could be too 

restrictive. Accordingly, EMA commented that EPA should give itself the authority to extend 

the time frame in special circumstances. (See §90.616 and §1054.695(b).) 

In later comments, EMA suggested that we allow an additional year for products that 

were produced in the United States, exported, and subsequently are imported again into the 

United States. 

Letters: 

Commenter Document # 

CARB 0682 

EMA 0691 

EMA 0808 

Our Response: 

 We are adopting the proposed provisions, as supported by the comments. We are not 

adopting the suggested allowance for approval under unique circumstances to allow a longer 

time frame to import products from earlier model years. We believe any such provision would 

invite any number of requests, each with unique circumstances. It is difficult to imagine a test 

that would allow us to establish a threshold that would appropriately differentiate legitimate 

requests from those that could or should have been avoided. In contrast, we believe the one-year 

allowance provides a generous amount of time to complete production for filling orders and 

shipping products to the United States. 

While the allowance is for a one-year difference between calendar year and model year, it 

is important to clarify that 12 months is the minimum time interval that would apply. This would 

be the case, for example, for an engine produced in December 2009 with new emission standards 

applying for the 2010 model year. Manufacturers would then have twelve months for shipment 

to an equipment manufacturer for installation and importation into the United States (or 

importation of the loose engine). Especially with the awareness that new emission standards 

have taken effect, we believe this presents a reasonable deadline for manufacturers to complete 

their production and shipping to get products into the United States. If manufacturers end their 

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model year before December of a given year, that would provide an additional margin for 

importing products by the end of the following calendar year. For products manufactured before 

the end of the model year, there would also be a correspondingly longer time until the 

importation deadline would apply. 

We are aware that seasonal products may pose unique challenges. However, we are not 

adopting a requirement that products reach the ultimate purchaser by the end of the calendar year 

following the named model year. Rather, these products must simply be imported before the 

deadline applies. We would expect manufacturers, distributors, or dealers to maintain their 

normal inventories of unsold products at their facilities within the United States without regard to 

the importation deadline described here. 

We believe it is also not appropriate to modify the regulation to accommodate products 

that are exported and are later imported. We believe this represents a rather unusual scenario, 

since it would be limited to products that are certified and labeled for current EPA standards 

even though they are exported. The engines or equipment would then need to be unused for 

more than a year before being sent back to the United States. Adopting such an exception would 

likely also be contrary to policy requirements related to international trade, since it would apply 

preferential treatment to domestically produced engines. 

See Section 1.5.2 for a discussion of issues related to stockpiling engines and equipment. 

2.10.4 Adding or changing governors 

What Commenters Said: 

EMA noted that the majority of all nonhandheld engines in this category have speed 

control governors, including engines used in small utility vehicles and go-carts. Because such 

engines have a high potential for over speed (operation at a speed higher than the intended design 

of the engine), such governor systems are critical to the safety and structural integrity of these 

engines. Parties that modify engines to replace or eliminate the use of an engine manufacturers 

speed control governor should be considered the manufacturer and should be held responsible for 

all aspects of the resulting product, including emissions compliance. In cases where an engine 

modification is an engine manufacturer approved configuration, the engine manufacturer must 

include this configuration in its determination of a worst case emission configuration for 

certification. Accordingly, EMA commented that no additional compliance determination 

should be required. 

EMA commented on §1054.650 “What special provisions apply for adding or changing 

governors?” EMA noted that this section states that the special provisions in the section apply 

for engines that will not have constant-speed governors when installed in equipment. However, 

there is no definition of what constitutes a “constant-speed governor.” Accordingly, EMA 

commented that EPA must provide such a definition in order to provide manufacturers with the 

ability to determine when the special provisions apply. 

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Letters: 

Commenter Document # 

EMA 0691 

Our Response: 

 We disagree with the comment suggesting that manufacturers simply include the range 

of governor strategies in an engine family by testing the worst-case configuration. The duty 

cycles we specify address only constant-speed engine operation. This is typical of generators, 

lawn mowers, and most other types of equipment. However, there are certain applications for 

which there is a governor to prevent overspeed but otherwise allows for operation at a wide 

range of engine speeds. It is not possible for manufacturers to consider the in-use operation of 

these variable-speed engines as part of its certification demonstration because we provide no 

standardized procedure for quantifying the emissions effect of this different operation. We have 

adopted a requirement in §1065.10(c)(1) to address this kind of mismatch between an engine’s 

in-use configuration (or operation) and that reflected in the certification test; this requires 

manufacturers to notify us of the mismatch and allows us to work out an alternate testing 

regimen to reconcile the discrepancy. We believe it is better to address this scenario directly in 

the regulations rather than attempting to resolve it over time under the provisions of 

§1065.10(c)(1). We could adopt a unique duty cycle for variable-speed engines. However, we 

believe these engines make up a very small portion of overall sales of Small SI engines and that 

it is therefore more appropriate at this time to require manufacturers to make an engineering 

demonstration that emission controls continue to work effectively at different engine speeds. We 

may pursue a different duty cycle in a future rulemaking if we find that this approach is not an 

effective way of addressing the concern. 

We agree that we need clarifying language to make clear what the regulation means by 

referring to constant-speed governors and have revised the language accordingly. 

We also agree with EMA’s suggestion to disallow removal or modification of installed 

governors without recertifying the engine. We have revised the language in §1054.650 to reflect 

this change. 

2.10.5 Competition exemption 

What Commenters Said: 

OPEI commented that it agreed with EPA’s reasoning and logic for determining what a 

“competition” engine is and how to apply for exemptions for their sale and use. 

Briggs and Stratton noted that in the current small engine regulations (40 CFR Part 90) an 

engine “Used solely for competition” is defined as “. . . exhibiting features that are not easily 

removed and that would render its use other than in competition unsafe, impractical, or highly 

unlikely” (40 CFR Part 90.3). In the Phase 3 proposal EPA is taking a different approach as 

described in the preamble on page 28140 in the Federal Register. The engines must meet all four 

of the listed criteria to be considered exempt based on use solely for competition. In order for 

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new engines to be exempt per §1054.620 an engine manufacturer would have to annually apply 

for the exemption and provide the information as required by EPA. 

Briggs and Stratton raised the following specific issues with regard to the proposal: 

1. Manufacturers that make engines specifically designed for competition have made 

investments to develop a product to comply with the criteria under existing regulations. 

The proposed regulations in §1054.620 create additional certification requirements, 

business limitations, and recordkeeping burdens in addition to the investment already 

made to comply with the current regulations. Briggs and Stratton suggested that the 

regulations allow engine makers to either meet the new criteria in §1054.620(c) or the 

existing criteria, which is: “Used solely for competition means exhibiting features that 

are not easily removed and that would render its use other than in competition unsafe, 

impractical, or highly unlikely”. 

2. The criteria in §1054.620(c) are written assuming that only professional racing teams 

use small engines for competition. However, amateurs competing in sanctioned events 

do much of the competitive racing using small engines. Therefore, Briggs and Stratton 

commented that the limitation for sale to the general public in §1054.620(c)(1) is not 

practical and this requirement should be deleted. 

3. The requirements to “document the ultimate purchaser” and “any equipment 

manufacturers requests for an exempted engine” in §1054.620(g) are not practical. As 

discussed above, amateurs that purchase engines through dealers serving the racing 

market perform much of the racing in sanctioned events. Dealers do not necessarily 

build the equipment but supply the parts used by amateur racers and engine/equipment 

builders that serve the racing market. Briggs and Stratton commented that 

§1054.620(g) should be modified to read: “If we request it, you must provide any 

information we need to determine whether the engines are used solely for competition. 

This would include any documentation regarding the number of engines and a list of 

the engine manufacturers’ customers for these engines. Keep these records for five 

years.” 

4. Section 1068.235 allows engines to be modified for competition after they are placed 

into service, to be modified without request, and no record keeping of these engines is 

required by the original engine manufacturer. Briggs and Stratton commented that 

§1068.235 should clarify that this exemption should not be used to circumvent the 

requirements of 1054.620. 

Letters: 

Commenter Document # 

OPEI 0675 

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Our Response: 

The existing definition under part 90 is very broad. Under the current program, 

manufacturers would need to show only that an engine or equipment has features that make 

noncompetition use impractical or unsafe. We believe this allows far too much discretion for 

manufacturers to claim product as being limited to competition purposes. There is also not any 

process under part 90 for EPA to review these determinations. We proposed a set of qualifying 

criteria and limitations and a corresponding process to approve a manufacturer’s use of this 

exemption. We believe these changes are needed to prevent exempted or excluded competition 

engines from being used for noncompetition purposes. The proposed provisions are very similar 

to those proposed or adopted in our other programs. 

The proposed criteria to qualify for the competition engines are explicitly not limited to 

professional racing teams. We proposed to allow for sales to “professional competition teams, 

professional competitors, or other qualified competitors.” We also proposed an approval process 

in which we could approve a competition exemption for manufacturers who could provide clear 

and convincing evidence that an engine would be used solely for competition even if not all the 

proposed criteria would apply. With respect to displaying competition models for sale to the 

general public, we believe it is important to avoid a situation where “unqualified competitors” 

are led to believe that they can purchase competition engines. It is therefore appropriate to keep 

the proposed limitation to prevent the “display for sale” of competition models. Allowing 

manufacturers to offer competition models for sale to the general public would prevent EPA and 

manufacturers from ensuring that purchasers will limit their use of these engines to sanctioned 

racing events. Manufacturers or dealers may display competition models to promote 

noncompetition models where it is clear that the competition models are not for sale to the 

general public. Qualified competitors should not be dependent on a manufacturer’s marketing to 

the general public to be able to find the engines and parts they need. We have modified the 

regulation to clarify that competition engines may be displayed at a public dealership, though 

they may not be displayed as a sales item. 

We agree with the suggestion to clarify that the allowance to modify certified engines to 

be used solely for competition should not be used to circumvent the requirements that apply 

under §1054.620 or similar provisions in other standard-setting parts. We have modified the 

language in §1068.235 to reflect this change. 

2.10.6 Alternate fuels 

What Commenters Said: 

OPEI and EMA supported EPA’s proposal that parties converting engines from a 

certified configuration to a non-certified configuration (i.e., from gasoline to propane) be 

required to certify the final product. OPEI and EMA commented that such parties should also be 

required to either remove or cover the original certified engine manufacturer emission 

compliance label with their own emission compliance label. As prescribed by the regulation, the 

party that certifies the final product should assume all responsibility for emission warranty, either 

directly or by contract with the original engine manufacturer. 

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EMA commented on §90.1003(b)(3)(i) and said that the language does not make sense 

and must be clarified. Significant components removed in the conversion process, such as 

carburetors, are not reinstalled but replaced in the conversion process. EMA also commented on 

§90.1003(b)(3) (ii) and believes the reference to §1054.635 is incorrect. EMA commented that 

the correct reference should be to §1054.645. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

The regulatory language in §90.1003 already refers to replaced components, as suggested 

in the comment. However, we believe the wording should be revised to address this confusion. 

We have therefore revised the language in §90.1003 accordingly. The revised language also 

includes a corrected reference to §1054.645. 

2.10.7 Hardship exemption 

What Commenters Said: 

OPEI strongly objected to EPA’s suggestion in the preamble that the proposed hardship 

relief measures in the Phase 3 regulation could somehow moot the independent need for the 

equipment-transitional flexibility program described above. Both proposed elements are critical 

to the industry and to the effective implementation of the final program. Moreover, there is 

substantial risk and uncertainty that EPA would not grant hardship relief requested by an 

individual OEM, at least until it is too late. By the time a manufacturer is in such duress that he 

can demonstrate and obtain hardship relief, it will typically be too late for him to make the 

needed production changes to avoid substantial economic injury. 

In its other regulatory programs, EPA has never indicated that the hardship relief was 

linked to, or somehow mooted the need for, the much broader, existing transitional flexibility 

programs for equipment manufacturers. This is because the hardship relief provisions are limited 

to extraordinary circumstances and require substantial administrative time and effort to obtain. 

For example, both the diesel engine regulations and the general provisions applicable to diesel 

engines, large spark-ignited engines (LSI), snowmobiles and off-road motorcycles include an 

independent hardship relief variance request for non-integrated equipment manufacturers. See 

§89.102(f); and §1068.255. For example, the Tier III and Tier IV diesel regulations allow for an 

additional 70% allowance for OEMS that demonstrate hardship relief. See §89.102(f) and 

§1039.625(m). 

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Letters: 

Commenter Document # 

OPEI 0675 

Our Response: 

EPA agrees that the TPEM program and hardship provisions are both needed for the 

Phase 3 program. The hardship provisions are intended to help manufacturers that are facing 

economic hardship as a result of not being able to comply with the new standards. The criteria 

for qualifying for hardship are set at a relatively high level, which would likely be difficult for a 

manufacturer to demonstrate if they were having difficulty redesigning only a few of their 

equipment models. The TPEM program allows an equipment manufacturer to deal with the 

models which are difficult to redesign without having to demonstrate that the company would 

experience hardship without the relief. Therefore, EPA agrees that both the TPEM program and 

the hardship provisions are needed and is retaining both of them for the Phase 3 program. 

2.10.8 Stockpiling provisions for engine manufacturers 

What Commenters Said: 

EMA shared that there is a general understanding that the inventory allowances described 

in §90.1003(b)(4) apply equally to engine manufacturers and equipment manufacturers. They 

also pointed out that it is not uncommon in the Small SI engine business for OEM's to order 

engines based on sales projections and then return engines or cancel orders after the engines are 

built if market conditions change. 

In response to draft language that would clarify the extent to which we would 

accommodate extended inventories for engine manufacturers, EMA commented that this 

approach seemed acceptable, with a remaining concern that the provision should not focus on 

small engine families. Engine families can consist of a wide variety of engine 

models/configurations. A high-volume family may include all the various models a 

manufacturer produces of vertical-shaft single-cylinder engines with a given displacement. The 

various models or customer-specific features may be as significant as a different crankshaft or as 

minor as a different styling element. Just because the family is high-volume doesn't mean that 

engines with a specific customer feature will not be stranded due to unforeseen changes in the 

market. Changing engines once they are manufactured and placed into inventory range from 

moderately expensive (trading out external parts) to ridiculously expensive (exchanging 

crankshafts). EMA suggested the regulatory language should state: "We will generally allow 

maintaining extended inventories only for unforeseen changes in market demand." 

Letters: 

Commenter Document # 

EMA 0817 

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Our Response: 

The issue raised by the commenters is being addressed by adding §1068.103(f) to 

explicitly prohibit stockpiling engines when new emission standards take effect and adding 

§1054.601(b) to explain how §1068.103(f) will apply for Small SI engines. The provisions of 

the new §1068.103(f) clarify that what is prohibited is for engine manufacturers to deviate from 

normal production and inventory practices to stockpile engines with a date of manufacture before 

new or changed emission standards take effect. This recognizes that typical production practices 

for most engine manufacturers involve engines remaining in the manufacturer’s inventory for 

some time. For most engines (especially for larger engines), since it is not economical to 

maintain a significant number of engines in inventory long after the end of a model year, this 

inventory time would typically be no more than a few weeks. 

However, Small SI engines can be kept in inventory for much longer times, especially for 

small volume engine models. Manufacturers noted other possible cases for such extended 

inventories. In response to these concerns, we are adding §1054.601(b) which describes how 

§1068.103(f) will apply for Small SI engines. This provision does not preclude manufacturers 

from keeping engines in inventory for long times. However, in recognition that normal Small SI 

practices can include keeping some engines in inventory for a very long time, §1054.601(b) will 

require that manufacturers obtain our approval to keep any engines in inventory for longer than 

12 months. Such manufacturers would be required to show that keeping such extended 

inventories is consistent with its normal business practice. In addition, given the lead time 

provided when we adopt new standards, we are requiring the manufacturer to demonstrate that 

the extended inventory (beyond 12 months) is also necessary and could not have been avoided 

through prudent planning. Consider the following examples: 

Example #1 – the manufacturer normally keeps certain small volume engines in inventory 

for up to three years. In this case, the manufacturer would need to plan its production run 

of such engines so that it reasonably expected to not keep any of the engines in inventory 

for more than 12 months after the new standards took effect. 

Example #2 – the manufacturer normally keeps engines in inventory for up to six months. 

In this case, the manufacturer could keep the engines in inventory for up to six months 

after the new standards took effect without seeking EPA approval. 

Example #3 – the manufacturer normally keeps engines in inventory for up to ten months, 

but receives a return of a large number of engines (unforeseen but consistent with its 

normal business practice) so that it will not use up its inventory for an additional four 

months. In this case, the manufacturer could keep the engines in inventory for up to 12 

months after the new standards took effect without seeking EPA approval. Engines 

remaining in inventory after 12 months could be scrapped, sold as replacement engines, 

exported, or covered under another applicable exemption. Alternatively, the 

manufacturer could ask to be allowed to sell the engines under its original certificate 

beyond the 12 month period. 

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It is worth noting that this 12 month limit is consistent with the provisions of §1068.360 

which prohibit the importation of new engines and new equipment in any calendar year that is 

more than one year after the named model year. 

2.10.9 Other issues under part 1068 

What Commenters Said: 

OPEI generally supported the proposed application of the Part 1068 Compliance 

Provisions to small engines. OPEI generally supported EPA’s efforts to modify Part 1068 to 

accommodate the application of evaporative standards which create different compliance 

obligations – depending on whether the OEM certifies or merely installs a previously certified 

evaporative component. (OPEI commented that they would like to work with EPA to further 

simplify/clarify this program so the component suppliers and OEMs can more readily understand 

their obligations and liabilities.) 

In response to EPA’s request for comment on applying these proposed requirements for 

engine rebuilding and maintenance to the engines and vehicles subject to this rulemaking, OPEI 

commented that it believes EPA may be creating burdens on industry segments unaware of this 

rule and incapable of providing the amount of burdensome records required by this part. OPEI 

commented that EPA should exempt engines/equipment subject to part 1054 from this provision. 

Letters: 

Commenter Document # 

OPEI 0675 

Our Response: 

 We agree that the provisions in part 1068 can and should apply broadly to engine 

categories, including Small SI engines. 

We also agree that the recordkeeping provisions related to rebuilding should apply 

differently for handheld and Class I engines. Commercial rebuilding for these engines is quite 

rare. We are concerned that applying the recordkeeping requirements for these engines will not 

be very meaningful for EPA’s oversight, and rebuilders could in many instances be unaware that 

their service has reached a point that would qualify as a rebuild and that recordkeeping 

requirements would therefore apply. These engines also generally have very simple systems for 

controlling emissions, so there is less of a need to carefully document part numbers for replaced 

components and other related records. We are therefore modifying the regulations to waive the 

recordkeeping requirement for engines with displacement below 225 cc. Note, however, that the 

underlying requirement to rebuild engines to the original certified configuration continues to 

apply. This requirement is simply an elaboration of the general prohibition against tampering 

with certified engines. Even small businesses rebuilding small numbers of small engines should 

not be exempt from the tampering prohibition. 

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In contrast, Class II engines (at or above 225 cc) are substantially more expensive and are 

much more likely to be used in commercial applications where commercial rebuilding can be 

expected to extend the engine’s operating life. We believe that commercial entities rebuilding 

these engines can be expected to maintain a standard business practice involving more careful 

documentation of their work. 

As described in Section 1.5.5, we believe this distinction for rebuilding engines below 

225 cc should apply equally to all spark-ignition engines (including recreational vehicles and 

outboard marine engines). 

2.11 Small business issues 

What Commenters Said: 

Although ECO believes that small volume engine manufacturers require flexibility to 

remain competitive in the market, ECO commented that it does not agree a complete pass on 

PLT testing is the correct approach. Instead, ECO encouraged EPA to develop an approach that 

maintains the integrity of the certification compliance process, while providing small volume 

manufacturers the flexibility needed to remain competitive. As a minimum requirement, ECO 

commented that at least one engine per family, per year, be tested to demonstrate ongoing 

compliance of production engines. As a second alternative, ECO suggested that EPA allow 

small volume engine manufacturers to utilize the use of alternative testing methods (portable 

emissions analyzers) to demonstrate in-use field testing compliance for production units. 

Letters: 

Commenter Document # 

ECO 0712 

Our Response: 

As part of the process of developing provisions for small businesses during the proposal, 

EPA identified 10 small businesses that are also small SI engine manufacturers. Based on 

estimated sales from the certification records, there companies represent less than 0.5% of small 

engine sales. The cost of performing testing for a PLT program are significant, especially for 

small companies that typically do not have their own emissions facility and must test at an 

independent lab. Even if we were to allow use of a portable system, the cost of such systems are 

still fairly expensive for the limited testing they would be used for. Due to the cost of running a 

PLT program and limited emission impact such a program could potentially have, we continue to 

believe that small volume engine manufacturers should be exempt from PLT testing. 

2.12 Other issues 

2.12.1 In-use testing 

What Commenters Said: 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

NACAA noted that data available in the EPA docket indicates in-use compliance failures 

by various models of lawn and garden equipment. This has been a continuing concern of 

NACAA and is heightened by the fact that EPA did not propose a mandatory in-use testing 

program for these engines. NACAA urged EPA to consider the addition of such an in-use 

testing program, consistent with the requirements for outboard and personal watercraft engines, 

to ensure in-use performance at the levels envisioned by the regulation. 

The Pennsylvania DEP noted that EPA has not proposed an in-use testing program for 

small spark-ignition engines despite the fact that in other recent proposals, EPA has treated inuse compliance as an important part of EPA’s program for ensuring performance throughout the 

useful life. The Pennsylvania DEP commented that EPA should consider an in-use compliance 

program. 

The MARC AQ Forum commented that the rule should establish a testing program to 

ensure that small engine emissions controls do not fail prematurely. 

NESCAUM commented that it is essential that the engines affected by this rulemaking 

meet the applicable standards for the entire useful life of the equipment into which they are 

installed. Consequently, they believe the proposed requirements for verifying durability of 

emissions controls are inadequate, principally because there are no requirements for in-use 

emissions testing. Consistent with the durability requirements pertaining to OB/PWC engines, 

NESCAUM urged EPA to incorporate similar requirements for manufacturers of small SI 

engines and equipment, including a robust in-use testing program. 

The Wisconsin DNR commented that EPA should consider the addition of a mandatory 

testing program for various models of lawn and garden equipment, to ensure in-use performance 

at the levels envisioned by the regulation. 

OPEI noted that handheld engines are very difficult to test. OPEI requested that EPA 

provide more detail in §1054.401 of the regulations. For example, OPEI asked whether EPA 

will use the same test method and fuel for an in-use test as for certification. In addition, they 

asked if EPA will use the same fixtures the manufacturer used. OPEI suggested that language be 

added stating that EPA would test at the manufacturer’s facility or request such fixtures from the 

handheld engine manufacturer. 

EMA commented on §1054.401 of the regulations. They believe this section should 

clarify that EPA will use the same test method and fuel as used for certification by the engine 

manufacturer. Accordingly, EMA commented that this section should be revised to read as 

follows: “We may perform in-use testing of any engine or equipment subject to the standards of 

this part using the test procedures and test fuels utilized by the manufacturer during the 

certification process.” 

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Letters: 

Commenter Document # 

NACAA 0651 

Pennsylvania DEP 0676 

MARC AQ Forum 0696 

NESCAUM 0641 

Wisconsin DNR 0663 

OPEI 0675 

EMA 0691 

Our Response: 

In response to the comments recommending an in-use test program for Small SI engines, 

EPA is not adopting such a program in the final rule. EPA did not propose an in-use test 

program as part of the proposal and therefore it is difficult for us to adopt such a requirement 

without a chance for people to comment on the specifics of an in-use testing program. Given the 

large numbers of engine designs currently certified, and the wide range of applications into 

which those engines are placed, designing a testing program to gauge the performance of in-use 

engines and equipment would not be an easy task. Plus, there could be significant costs 

associated for manufacturers in running such a program depending on how the program is 

designed. EPA believes an in-use program for Small SI engines is something that should be 

given full consideration as part of a future rulemaking. 

While an in-use test program could be a useful tool to determine whether in-use 

engines/equipment are complying with the standards, it is not the only way. In addition to 

certification testing, EPA requires manufacturers to perform production line testing to 

demonstrate that engines coming off the production line are emitting at the expected levels. 

Furthermore, EPA has the authority to perform selective enforcement audit (SEA) testing where 

engines coming off the production line are tested with EPA in attendance for the testing. Finally, 

EPA recently initiated its own on-going confirmatory test program that is expected to test a wide 

range of small engines in the coming years (not necessarily including engines that have already 

been placed into service). While none of these programs on their own can ensure engines will 

meet the standard in use, each will help to encourage manufacturers to produce well-designed 

engines that continue to meet the emission standards throughout their lifetime. 

In regard to the comments that EPA should provide more details on how it would 

perform its own in-use testing, EPA has made one change to §1054.401 of the regulations. The 

regulation notes that EPA will consult with the manufacturer as needed to be able to perform a 

valid emission test. To the extent that engines can’t be tested without unique fixtures or other 

approved “special test procedures” (see §1065.10(c)(2)), we would generally duplicate the 

methods used by the manufacturer for certification testing. This could involve testing at the 

manufacturer’s facility or at any test facility we designate. This intent to duplicate the 

manufacturers’ procedures does not apply for approved “alternate test procedures” for in-use 

testing (see §1065.10(c)(7)). Alternate test procedures are approved by EPA because they are 

expected to result in emission levels similar to what would result from the standard test 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

procedure. Therefore, although we may choose to do so, EPA sees no reason to commit to using 

an “alternate test procedure” for testing in-use engines. 

With regard to test fuel used for in-use testing, EPA has made a change to the regulatory 

provisions. As described in Section 2.5.4, we are finalizing provisions that will allow 

manufacturers to use a 10 percent ethanol blend for certification testing for exhaust emissions 

from nonhandheld engines, as an alternative to the standard test fuel (Indolene). This option to 

use a 10 percent ethanol blend for certification of nonhandheld engines will begin with the 

implementation date of the Phase 3 exhaust standards and would apply to production-line testing 

as well. We are also committing to using a 10 percent ethanol blend for all confirmatory testing 

we perform for nonhandheld engines certified on the ethanol blend, under conditions specified in 

Section 2.5.4. Our commitment to test on an ethanol blend for those nonhandheld engines 

certified on an ethanol blend has been noted in §1054.501 of the regulations. 

For handheld engines, we are not committing to using the same fuel as the manufacturer 

used for certification testing. EPA would expect to use Indolene for all in-use testing of 

handheld engines, although we could decide, at our own discretion, to do exhaust emissions 

testing using the certification fuel used by the manufacturer. 

With regard to the fixtures used for testing handheld engines, EPA has not made any 

changes to the regulations. For any in-use testing, EPA would expect to contact manufacturers 

to ensure that we are testing engines in a manner that is appropriate for operating the equipment 

on an engine dynamometer. While this may include requesting a fixture from the engine 

manufacturer, EPA does not believe this will always be necessary and will not commit to doing 

so at this time. 

2.12.2 Voluntary green labeling program 

What Commenters Said: 

NESCAUM commented that they support the concept of a “green labeling” program, as a 

means to make consumers aware of which engines exhibit especially clean emissions 

performance as consumers make their equipment choices. In the Phase 2 rulemakings for 

handheld and nonhandheld SI engines, EPA committed to “pursue the development of a 

voluntary green labeling program for small SI engines as a non-regulatory program.” 

NESCAUM noted that more than eight years have now elapsed since EPA made this 

commitment and as yet, there is no such program. NESCAUM urged EPA, through this 

rulemaking, to renew its commitment to work with stakeholders to develop a green labeling 

program. 

Letters: 

Commenter Document # 

NESCAUM 0641 

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Chapter 2: Small SI Engines 

Our Response: 

EPA is not prepared to commit to developing a voluntary green labeling program for the 

Phase 3 standards at this time. In several previous rulemakings, EPA has adopted provisions 

allowing manufacturers to certify to “Blue Sky” standards in the nonroad diesel, marine diesel, 

and large SI categories. These Blue Sky standards are more stringent than the regularly 

applicable standards and allow manufacturers to note such compliance on the engine label. 

While we have had such standards in place since 1998, no manufacturer has yet certified an 

engine under these standards. Therefore, while we could consider a voluntary labeling program, 

we are not convinced that manufacturers are interested in participating in such a program. While 

EPA could pursue a voluntary program in the future, we are not committing to developing a 

program for the Phase 3 standards in this rule. 

2.12.3 Miscellaneous Issues 

What Commenters Said: 

EMA commented that §1054.15(b) “Do any other regulation parts apply to me?” states 

that Part 1065 describes procedures and equipment specification for testing engines. However, 

Part 1065 only provides this information regarding exhaust emission testing, not evaporative 

emission testing. Accordingly, EMA commented that this section should be revised to read as 

follows: “Part 1065 of this chapter describes procedures and equipment specifications for 

exhaust emission testing engines. Subpart F of this . . .” 

EMA noted that §1054.101(b) states that HC and NOx exhaust emissions are optional for 

wintertime engines. However, §1054.101(d) states that two-stroke snowthrower engines may 

meet exhaust emissions standards that apply to handheld engines with the same engine 

displacement. In order to avoid any confusion between the requirements set forth in 

§1054.101(b) and (d), EMA commented that §1054.101(d) should be revised to read as follows: 

“Notwithstanding the provisions of subpart (b) of this part, two-stroke . . .” 

EMA commented on §1054.205(a) “What must I include in my application?” EMA 

commented that it is not clear what information is required for engine families where the 

certification test engine has a maximum modal power in excess of 15 kW. Accordingly, this 

section should be revised to read as follows: “For each engine family in which the maximum 

modal power of the emission-data engine is at or above 15kW, provide the nominal brake power 

for engines included in the engine family as described in 40 CFR Part 1054.140.” 

EMA commented on §1054.235(e) “What exhaust emission testing must I perform for 

my application for certification of conformity?” EMA noted that pursuant to this section, EPA 

may require a second engine to be tested. However, the section fails to define how the “official” 

results of such testing will be determined. EMA recommended that EPA’s current practice – 

which is to use the average of the results obtained – be included in the final rule. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

G. Alcock commented that there is a very important overriding consideration regarding 

all leaf blowers. The particulates sent into the air in the process of 'blowing' far outweigh the 

combustion output as regards overall pollution. Leaf blowers should be banned entirely. Leaf 

vacuums are far more efficient and could even be restricted to electrical power sources. All 

homes have external electrical outlets. To limit the financial business loss of leaf blower 

manufacturers (which should not be the criteria by which laws are considered) would be the 

conversion of leaf blowers to vacuums. Innovation would allow designs for these modifications 

and a much cleaner environment would result. In Arizona's attempts at legislation, the ban was 

immediately thrown out because it would hurt the manufacturer of leaf blowers. This is the tail 

wagging the dog. They said use of leaf blowers would be limited to high pollution days. Every 

time a leaf blower is used the local area becomes a high pollution day. 

Letters: 

Commenter Document # 

EMA 0691 

G. Alcock 0601 

Our Response: 

 We agree that §1054.15(b) should be changed to focus on exhaust emissions. The 

regulations have been changed accordingly. 

We agree that §1054.101(b) and (d) from the proposal need to be reconciled. We have 

combined these into a single paragraph and added the clarification that the handheld HC+NOx 

standards apply to the two-stroke snowthrower engines if they are certified to the handheld 

standards. 

We believe the proposed requirement to identify maximum engine power for engines 

with maximum modal power over 15 kW is exceptionally clear. Maximum engine power is a 

defined term (see §1054.140), as noted by EMA’s comments on that subject. Maximum engine 

power is the parameter used to determine whether engines are subject to the requirements of part 

1054, so any other information would not be suitable for identifying the engine family in 

§1054.205(a). Note that we are revising the regulation to require reporting of maximum engine 

power for engines with displacement at or below 1000 cc only if maximum modal power is at or 

above 25 kW. 

We disagree with EMA’s suggestion that we should specify in §1054.235(e) that the 

results from a second engine tested by the manufacturer should be averaged with the results from 

the first engine to determine the official result for the engine family. The regulations at 

§1054.240(a) specifically state that all engines tested for certification need to comply with 

emission standards. Allowing the averaging approach would allow manufacturers to have a test 

engine with emissions above the standard that is offset by an engine from the same family that 

has lower emissions. This is clearly incompatible with the principle that the test engine needs to 

represent the worst-case configuration and that every engine produced under the engine family 

must meet emission standards. This is consistent with the current regulations at §90.104(a), 

which also require that all test engines meet applicable standards. 

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We understand that there are certain quality-of-life concerns regarding the use of Small 

SI engines. We encourage the responsible use of leaf blowers and other types of equipment that 

may be operated in neighborhoods or in other areas where people may be sensitive to the use of 

such equipment. However, the Clean Air Act directs us to set emission standards for these 

products without giving us the authority to limit the use or sale of these products. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

3 Exhaust Emission Standards and Related Requirements for 

Marine SI Engines 

What We Proposed: 

The comments in this section generally correspond to Sections III, IV, and VII of the 

preamble to the proposed rule, where we describe the proposed emission standards and 

certification procedures associated with exhaust emissions from Marine SI engines. The 

applicable regulatory provisions for these proposed requirements are in 40 CFR part 1045. The 

Regulatory Impact Analysis describes the feasibility of these standards, special provisions that 

apply to small businesses, and alternative standards under consideration in Chapters 4, 10, and 

11, respectively. There are also several technical amendments to the regulatory provisions in 40 

CFR part 91. 

See Chapter 1 of this document for a discussion of issues that apply more broadly than only 

for Marine SI engines. See Chapter 4 of this document for a discussion if issues related to 

evaporative emissions. 

3.1 Scope and applicability 

3.1.1 Differentiating Small SI and Marine SI engines 

See Section 3.12.3 for a discussion of issues related to installation of certified Small SI 

engines in marine vessels. 

3.1.2 OB/PWC and SD/I definitions 

What Commenters Said: 

NMMA and Brunswick commented that they have no objections to creating a single term 

that would include both sterndrive and inboard engines in a single category of engines and that 

also clarifies that hovercraft and air boats are specifically included in this engine category. 

BRP and Yamaha commented that they use PWC engines to propel their jet boat products 

(also called “sport boats”), which would be classified as sterndrive/inboard under the new 

regulations. BRP commented that both EPA and CARB currently categorize Sport Boats with 

outboards and personal watercraft. Currently, BRP certifies its Sport Boat models in the same 

engine families as PWC models for both EPA and CARB. BRP and Yamaha commented that 

including jet boat engines in the SD/I category creates a new more stringent set of emission 

standards for these engines. Both manufacturers commented that this is only appropriate if jet 

boats are given sufficient lead time to comply with the standards and the corporate average 

provision is expanded to allow CO averaging. 

3-1 
Chapter 3: Marine SI Engines 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Yamaha 0721 

Mercury 0693 

Our Response: 

We are finalizing the definition of sterndrive/inboard engines as proposed. We believe 

classifying engines used in hovercraft, air boats, and jet boats as SD/I engines is appropriate 

because it will subject the engines in these applications to the same emission standards as other 

boats with similar size, power, and usage characteristics. As described in Section 3.2.3, we are 

providing flexibility in meeting the new emission standards for jet boat engines because they are 

currently designed to use engines derived from OB/PWC applications and because of their 

relatively low sales volumes. We believe that this flexibility, coupled with the additional lead 

time, addresses the comments raised by BRP and Yamaha regarding lead time and CO 

averaging. 

3.1.3 Maximum engine power and displacement 

What Commenters Said: 

NMMA and Mercury Marine commented on § 1045.140 at which EPA defines 

“maximum engine power” as the “maximum brakepower point on the nominal power curve for 

the engine configuration.” 72 Fed. Reg. at 28,268. Section § 1045.140(b) states that “[t]he 

nominal power curve of an engine configuration is the relationship between maximum available 

engine brake power and engine speed for an engine, using the mapping procedures of 40 CFR 

part 1065, based on the manufacturer’s design and production specifications for the engine.” Id. 

The reference to the mapping procedures in Part 1065 is inappropriate. Under EPA’s current 

regulations for OB and PWC engines, manufacturers use SAE J1228 to determine maximum 

power, and the California regulations also require the use of SAE J1228. For the EU, 

manufacturers use ISO 8665, which is equivalent to the SAE standard. EPA’s proposal to require 

the procedures in Part 1065 would be inconsistent with these existing requirements and, 

importantly, would require significant additional testing over and above what is required for 

compliance with the California and EU requirements. This considerable cost burden on 

manufacturers is unjustified given there is no environmental benefit. NMMA recommends that 

EPA replace the reference to Part 1065 with SAE J1228 and ISO 8665. This would ensure 

consistency among the different regulatory schemes and reduce unnecessary compliance costs. 

Indmar has concern over the procedure for establishing the nominal power curve and the 

resulting rated speed and rated power. California and the European Union use SAE J1228 or ISO 

8665 (same except for English vs. metric). Section 1045.140(b) references 40 CFR part 1065 and 

should reference SAE J1228. They think EPA should remain common with CARB and 

eliminate the possibility of duplicate testing for EPA at a slightly different power level. 

3-2
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Bombardier commented that in 40 CFR 1045.140, EPA is proposing to redefine how 

maximum engine power is determined on marine spark-ignited engines by changing the current 

engine mapping procedures from SAE J1228 to 40 CFR 1065. Currently, the marine industry 

follows the procedures of SAE J1228 for EPA and CARB and ISO 8665 (functionally equivalent 

to SAE J1228) for the European Union (EU). By changing the mapping procedures for marine 

spark-ignited engines, EPA is forcing manufacturers to run a different test procedure for EPA 

than done for CARB and the European Union. This would impose a significant additional test 

burden on a manufacturer. BRP recommends EPA replace the reference to 40 CFR part 1065 

with SAE J1228 and ISO 8665 to maintain harmonization with CARB and the EU. 

Yamaha commented that EPA has elected to establish a test protocol that is without merit 

and will add increased cost to certification, possible additional costs for dyno 

replacements/updates and will not harmonize with what currently both the CARB and EU utilize 

which is SAE 1228 or the ISO equivalent for this purpose. Yamaha requests that EPA adopt the 

NMMA language of continued use of SAE J1228 for this purpose to harmonize on an 

International basis. 

Letters: 

Commenter Document # 

NMMA 0688 

Indmar 0667 

Bombardier 0674 

Yamaha 0721 

Mercury 0693 

Our Response: 

 The regulations rely on the value for maximum engine power to establish which 

standards apply and to calculate emission credits. For example, the regulations include emission 

standards that differ for power ratings at 4.3, 30, 40, 250, 373, and 485 kW. It is important to 

have an objective method for establishing an engine’s power rating for determining which 

standards apply and for calculating emission credits. The current regulations and the published 

SAE and ISO procedures direct the manufacturer to declare a value for rated power without any 

clear direction to establish that value based on an engine’s power map or other operating 

characteristics. 

It is true that manufacturers would need to run an engine map for each engine, but we 

expect that this is already common practice to establish the engine’s power characteristics and 

determine the recommended prop range. Therefore, we disagree that the definition of maximum 

engine power in 40CFR 1045.140 will increase testing costs. 

Note that maximum engine power is not related to testing engines. The relevant 

parameter for testing is maximum test speed. Manufacturers raised similar concerns about our 

approach for establishing maximum test speed, which we describe in Section 3.9.1. 

3-3 
Chapter 3: Marine SI Engines 

3.1.4 Fuel additives for reducing emissions 

What Commenters Said: 

Pure Power commented regarding their EcoFuelTM Mach 3 Gasoline & Diesel Additive. 

They claim that independent test results reported by ATDS, Inc, Ontario, CA, (recognized by the 

EPA and CARB for automotive emission and fuel consumption) from both gasoline and diesel 

powered cars and trucks showed “across the board” reductions as high as: NOx (44%), HC 

(16.3%), CO (4.5%), opacity smoke (30.4%), particulates (18.3%), in addition to a 14% 

reduction in fuel consumption. 

Pure Power also commented that their ThrustorTM & Schultz NozzleTM Marine 

Propulsion System reduces fuel consumption, while increasing overall vessel performance. The 

ThrustorTM is designed to mount on the anti-cavitation plate and skeg for all outboard and stern 

drive boats. The Schultz NozzleTM mounts to the vessel hull. Conservative projected fuel 

savings between 10% and 20% depending on vessels size and speed. 

Letters: 

Commenter Document # 

Pure Power 0664 

Our Response: 

Our regulations are intended to be fuel neutral and would not preclude the use of these 

fuels or additives. However, anyone wishing to obtain a certificate of conformity that relies on 

the use of a fuel that is not widely available or that relies on any particular additive would be 

required to demonstrate that the engines would consistently operate with such fuels or additives 

during in-use operation. Moreover 40 CFR 1068.101(b)(1) prohibits using the incorrect fuel if it 

renders the emission control inoperative. 

3.1.5 Natural gas and LPG engines 

What Commenters Said: 

Rolls Royce submitted comment asking what legislation EPA will apply to our [natural] 

gas engines if they are to be used in marine application. Has EPA had a chance to check this? 

Nautigaz shared commercial information related to their system for converting gasolinefueled marine engines for operation on LPG. They pointed out the energy-security advantages of 

LPG based on the extensive domestic production of LPG fuels within the United States. They 

also maintained that engines operating on LPG will always be less polluting than diesel-fueled or 

gasoline-fueled engines. Nautigaz also pointed out various technical parameters of interest in 

designing marine systems, such as corrosion control, the advantages of fuel-level indicators and 

anti-deflagration devices. 

3-4
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

Rolls Royce 0715 

Nautigaz 0727 

Our Response: 

Oceangoing vessels that transport natural gas as a commodity product are increasingly 

using the stored (and vented) natural gas to fuel the ship’s propulsion engines. The comment 

from Rolls Royce helped us realize that these engines would likely be subject to our Marine SI 

standards under the wording of the proposed regulations. These engines might be 20,000 or 

30,000 kW, so the certification and testing protocol we have developed for Marine SI 

technologies would clearly not apply for these larger engines. To address this, we have revised 

the regulations to specify that natural gas engines above 250 kW would need to meet the 

standards that apply for marine compression-ignition engines. All automotive-type engines 

using natural gas today are less than 250 kW so this threshold should properly differentiate 

engines installed in conventional sterndrive and inboard vessels from the diesel-derived natural 

gas engines used in workboats and other commercial vessels. This is consistent with the recently 

adopted provision of 40 CFR 1042.1(e). 

The emission standards in this rule are fuel neutral. Manufacturers may certify engines 

using LPG, gasoline, or other fuels. It may be possible for LPG-fueled engines to reach lower 

emission levels than gasoline-fueled engines, but our observation across the various engine 

categories is that catalyst-equipped engines have comparable emission levels whether they are 

fueled by gasoline, LPG, or natural gas. Diesel-fueled engines are subject to a totally different 

set of emission standards and other regulatory requirements. 

3.2 SD/I standards and lead time 

3.2.1 SD/I standards–level 

What Commenters Said: 

NMMA, Mercury Marine, Indmar, MECA, NACAA, Pennsylvania DEP, New York 

DEC, NESCAUM, and Environmental Defense support the HC+NOx standards of 5.0 g/kWh 

and CO limit of 75 g/kWh proposed by EPA for the SD/I engines. 

NMMA stated that EPA is proposing a 5 g/kW-hr standard for HC+NOx and a 75 g/kWhr standard for CO for SD/I engines starting in model year 2009. 72 Fed. Reg. at 28,263 

(proposed § 1045.105). While NMMA fully supports the level of the proposed emission limits 

for HC+NOx and CO in § 1045.105(a), the 2009 model year implementation date is not feasible 

for the recreational marine industry. 

Mercury fully supports the exhaust standards for SD/I Engines provided that the 

implementation dates are adjusted to provide necessary lead time. 

3-5 
Chapter 3: Marine SI Engines 

Sea Ray wants to take this opportunity to express its concerns about the robustness of 

catalyst systems in the salt water environment. Since testing was never completed, CA will serve 

as a validation and feedback opportunity to all of us. The industry needs the additional time to 

understand what the problems might be should they arise. 

Indmar commented that they were also actively involved in the test program to prove the 

technical feasibility of catalytic converters on SD/I engines for their useful life (480 hours) in 

both fresh and salt water. They supplied two boats as well as technical support to Southwest 

Research Institute to conduct the test program. They support the proposed federal emission 

regulations for new marine spark-ignited sterndrive/inboard engines that will substantially reduce 

emissions from these engines. 

NMMA submitted comments regarding the Southwest Research Institute (SwRI) 

Saltwater Test Program. Even though the SwRI tests never proved catalyst feasibility in salt 

water, their members believe that, at this stage of catalyst development, there is little or no 

additional data to be obtained by completing the tests. The designs being tested at SwRI are not 

designs that any of the engine companies are considering pursuing. Whether or not they could 

survive 480 hours is of no value. Their members have their own compliance plans that include 

designs that appear to withstand saltwater operation, although they will not know for sure until it 

gets into the hands of customers. Therefore, NMMA agreed that EPA and CARB should 

discontinue the SwRI saltwater test program. 

NMMA continued that in the context of EPA’s recently proposed rules for exhaust 

controls for marine engines, there is a continuing concern regarding catalyst and sensor 

durability, especially in salt water, and in engine technologies not included in the SwRI test 

programs, for example, personal watercraft engines installed in jetboats. The manufacturers of 

those items also have been unable to provide any help to the engine manufacturers in this regard 

as they have no experience in the salt water environment. NMMA stated that it is critical to both 

the marine industry and the hundreds of thousands of American jobs that are created by this 

industry, that EPA delay implementation of any nationwide catalyst-based rule until the 

manufacturers have studied the effect of the catalyst through a complete warranty cycle (three 

years) and the manufacturers gain the necessary field experience in California. In any waiver 

decision regarding catalysts for SD/I, they commented that EPA must make clear that it is not 

predetermining the outcome of the ongoing rulemaking, and that if durability problems should 

arise in actual use in California, that EPA will work with CARB and engine manufacturers to 

adjust any rules applicable to these engines. 

NACAA commented that with respect to marine spark-ignition engines and vessels, 

NACAA supports EPA’s proposal to set CO standards for all sectors. We also support the 

agency’s proposal to establish the first-ever federal standards for vessels powered by sterndrive 

or inboard engines. 

Pennsylvania DEP supports EPA’s proposed standards and implementation schedule for 

marine spark-ignition engines and vessels. 

3-6
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

New York DEC stated that EPA proposes to adopt standards similar to California’s, 

resulting in a 70% reduction in combined hydrocarbon and oxides of nitrogen (NOx) emissions. 

The Department supports the proposed emission standards, including not-to-exceed (NTE) 

standards and the requirement for closed crankcases. 

NESCAUM supports EPA’s effort to harmonize the federal emissions standards with 

those standards already adopted in California. In many respects, the proposed federal standards 

are identical to or analogous with California standards. This approach will make it easier for the 

engine and equipment manufacturers to provide 50-state products to the U.S. market. 

Environmental Defense supports EPA’s proposal to establish HC+NOx exhaust emission 

standard of 5g/kW-hr for sterndrive and inboard marine engines (SD/I engines). These standards 

are identical to those adopted by CARB. The proposed exhaust emissions standards represent 

significant reductions of 70% in HC and NOx and 50% in CO emissions. EPA predicts engine 

manufacturers will meet these standards by incorporating catalysts into the water-cooled exhaust 

systems used for these engines. Environmental Defense applauds the Agency for taking the 

initiative to set a carbon monoxide exhaust emission standard for SD/I engines for the first time. 

The addition of a CO standard should not impose any additional costs on engine manufactures 

since the same catalyst technology used to achieve the HC and NOx standards will ensure that 

the new CO standard is met as well. 

MECA stated that the technology to reduce emissions from spark-ignited inboard and 

sterndrive marine engines will be based on automotive-type three-way catalyst with closed-loop 

control technology. This technology has been used on well over 300,000,000 automobiles with 

outstanding results and the same technologies can be adapted to marine inboard and sterndrive 

engines. Here again results from EPA and ARB sponsored test programs detailed in the EPA 

Draft Regulatory Impact Analysis confirm that three-way catalysts (TWCs) can be effectively 

integrated into marine inboard and sterndrive engines, and TWCs have the necessary mechanical 

integrity and catalytic durability to perform with high emission conversion efficiencies 

throughout the entire 480-hour useful life emissions requirement for these marine engines, 

regardless of operation in fresh or salt water environments. Important results from this 

demonstration program included the design and integration of exhaust manifolds with TWCs that 

provided relatively low exhaust manifold surface temperatures (through the use of a waterjacketed exhaust system) and minimized the potential for water ingestion into the region of the 

manifolds that contained the TWCs. Both ceramic- and metallic-based substrates were used to 

display a range of three-way catalyst formulations as a part of this durability test program, all 

with good results. Thus, a variety of TWC technology options used successfully in automotive 

applications were shown to be effective in these marine engine applications. The early 

commercial introduction of a catalyst-equipped marine inboard engine is further proof that 

catalyst can be used to achieve EPA’s proposed HC+NOx and CO standards for this category of 

Marine SI engines. 

SCAQMD staff believes that more stringent standards for this category are also 

appropriate, technically feasible, and absolutely critical for the South Coast Air Basin to meet its 

PM 2.5 and 8 hour ozone standards. Engines in this category are closely related to automobile 

engines which have achieved much lower emission levels using advanced emission control 

3-7 
Chapter 3: Marine SI Engines 

systems for more than 20 years. Successful transfer of this technology to land based nonroad 

engines (which are also similar to automobile engines) has lead the California Air Resources 

Board and the U.S. EPA to adopt exhaust standards that will require new engines to meet exhaust 

levels two times, and by 2010, five times more stringent than those levels proposed in this rule. 

See 3.2.3 for comments specifically related to jet boat engines. See 3.4 for comments 

specifically related to high-performance engines. 

Letters: 

Commenter Document # 

Sea Ray 0683 

South Coast AQMD 0704 

NY DEC 0659 

NESCAUM 0641 

Environmental Defense 0648 

NACAA 0651 

Indmar 0667 

Mercury 0721 

MECA 0668 

Pennsylvania DEP 0676 

Our Response: 

As supported by the majority of commenters, we are adopting the proposed exhaust 

emissions standards for SD/I engines of 5 g/kWh HC+NOx and 75 g/kWh CO. The final 

HC+NOx standards are similar to the California ARB emissions standards for HC+NOx that 

began in 2008. We believe the type of catalyst used to achieve the HC+NOx standard will also 

be effective in reducing CO emissions enough to meet the new standard, therefore no additional 

technology will be needed to control CO emissions. 

We believe the final federal exhaust emission standards for SD/I engines represent the 

greatest degree of emission reduction feasible in this time frame. Over the past few years, 

developmental programs have demonstrated the capabilities of achieving significant reductions 

in exhaust emissions from SD/I engines. Chapter 4 of the Final RIA presents data from several 

of the SD/I engines with catalysts that were tested as part of the development of the standards 

had HC+NOx emission rates lower that 5 g/kW-hr, even with consideration of expected in-use 

emissions deterioration associated with catalyst aging. The goal of the testing was to 

demonstrate catalysts that will work within the packaging constraints associated with water 

jacketing the exhaust and fitting the engines into engine compartments on boats. California ARB 

has acted on this information to set an HC+NOx emission standard of 5 g/kW-hr for SD/I 

engines, starting in 2008. At this time, three engine manufacturers have certified SD/I engines to 

these standards. In addition, Chapter 4 of the Final RIA presents data from these engines as 

detailed data on several developmental SD/I engines with catalysts packaged within watercooled exhaust manifolds. Four of the developmental engines in our test program were operated 

with catalysts in vessels for 480 hours. The remaining developmental engines were tested with 

catalysts that had been subjected to a rapid-aging cycle in the laboratory. As stated in their 

3-8
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

comments, Indmar has demonstrated the durability of catalysts over their full useful life of SD/I 

engines, both in fresh and salt water. Data from these catalyst-equipped engines also support the 

level of the standards. We also performed testing on SD/I engines equipped with both catalysts 

and EGR. Although this testing showed emission results in the 2-3 g/kW-hr range, we expect 

that similar reductions could be achieved more simply through the use of larger catalysts or 

catalysts with higher precious metal loading. 

Past experience, in other engine categories, indicates that most manufacturers will strive 

to achieve emission reductions well below the final standards to give them certainty that they 

will pass the standards in-use, especially as catalysts on SD/I engines are a new technology. 

Therefore, we believe the emission standards for SD/I engines represent the greatest degree of 

emission reductions achievable taking into consideration the potential variability in in-use 

performance and in test data mean and do not believe it would be appropriate at this time to set a 

lower standard for these engines. 

3.2.2 SD/I standards–lead time 

What Commenters Said: 

NMMA and Mercury Marine stated that while SD/I engine manufacturers have started 

the necessary research and development to produce engines and emission control systems to 

comply with the 2008 CARB standards, the California market represents only a small portion of 

the national marine engine market. As a result, they argued that some manufacturers will limit 

the engine models offered in California because there is not sufficient lead time to reconfigure 

their entire product line. They commented that the implementation date for the federal emissions 

standards must take into account the challenge of designing catalyst-based systems for all 

engines across the entire SD/I engine market. Mercury Marine adds that due to the issue of a 

major change in base engines supplied by GM (see below) a 2009 implementation date would 

force Mercury to apply for hardship relief as soon as the rule is finalized. This is not the way 

they would like to start off a new rule. 

NMMA and Mercury Marine stated that EPA is proposing a 5 g/kW-hr standard for 

HC+NOx and a 75 g/kW- hr standard for CO for SD/I engines starting in model year 2009. 72 

Fed. Reg. at 28,263 (proposed § 1045.105). While NMMA fully supports the level of the 

proposed emission limits for HC+NOx and CO in § 1045.105(a), the 2009 model year 

implementation date is not feasible for the recreational marine industry. NMMA has worked 

cooperatively with EPA over the past several years to share data and information on the status of 

the development of catalyst technology that can be used effectively and safely in both fresh and 

saltwater environments. While the technology is commercially available, the ability of 

manufacturers to develop catalysts and reconfigure all of their engines to accommodate catalystequipped exhaust systems by model year 2009 is not realistic for several important reasons that 

are specific to how the marine engine industry is structured. 

NMMA urges EPA to adopt in the final rule the third option for implementation 

discussed—full compliance with the emission limits in model year 2010 for all SD/I engines 

except for the replacement engines for the 4.3L and the 8.1L and personal watercraft engines 

installed in jet boats, which should have until model year 2011 to comply. Mercury Marine is 

3-9 
Chapter 3: Marine SI Engines 

limiting model availability in CA for 2008 – 2009 and needs until 2010 to have all of the 

horsepower levels covered for a National Rule. Mercury Marine has supplied a confidential list 

to EPA of the engines and power ratings that will not be available as catalyst engines for 2008 – 

2009 and will not be sold in California. 

NMMA and Mercury Marine commented as EPA notes in the preamble, a large number 

of SD/I engines are based on automotive engine blocks produced by General Motors (GM). 72 

Fed. Reg. at 28,115. EPA also correctly points out that GM plans to discontinue production of 

the 4.3L and 8.1L engine blocks in 2009 and instead plans to offer a 4.1L engine block and a 

6.0L supercharged engine as replacements. There are significant market and compliance 

implications associated with GM’s product plans, which the NMMA-suggested compliance 

schedule would address. From a cost perspective (which EPA correctly identifies in the 

preamble), the small number of remaining years of sales of the 4.3L and 8.1L fail to justify the 

considerable costs associated with developing catalyst-based exhaust systems for these engines. 

From a compliance timing perspective, manufacturers that marinize the replacement engines will 

only be able to start designing catalyst systems sometime late this year when it is expected that 

manufacturers will see the first prototypes of the replacement engines. The development cycle 

for marinizing the base engine is over two years for some companies. Thus, a model year 2009 

implementation date does not allow enough lead time for the industry to marinize the 

replacement engines and develop exhaust control systems. 

Mercury Marine added that CARB has already provided relief on these engines for 2008 

and 2009. The development cycle for marinizing the base engine is three years. Production base 

engines from GM are not scheduled to be available until 2010, and that assumes they maintain 

their current schedule. They commented that they have already been advised that the GM 

timeline has slipped a few months. Furthermore, having to develop these new engines as catalyst 

marine engines is taking resources away from being able to develop catalyst versions of the 

engines listed above that will not be available in California. Mercury Marine commented that the 

workload is more than can be accomplished to launch all of these new and modified engines on a 

national level before 2010 – 2011. 

NMMA also commented that the other option for implementation that EPA suggests is to 

allow an additional year for the engines not using catalysts in California in 2008, namely the 

4.3L and the 8.1L. NMMA stated that the model year 2009 is not practical and that an additional 

year for these engines until model year 2010 is appropriate and justified. California’s marine 

engine standards will require catalysts on engines (other than the two engines noted above) 

starting in model year 2008. In light of this short lead time and the number of different products 

offered, NMMA argued that marine engine manufacturers will not have the ability to fully 

catalyze their entire line of engines for California in that time frame. Also important to consider 

is that the California market constitutes only a small percentage of the marine engine market 

(unlike the case with motor vehicles, which is larger than the percent of the overall population). 

Thus, marine engine manufacturers will in some cases limit the engines available in California to 

those that can be readily catalyzed and will continue to sell a mix of catalyzed and noncatalyzed 

engines in the other 49 states in 2008 and 2009. NMMA stated that, by model year 2010, engine 

manufacturers should have the necessary lead time required by Clean Air Act § 213 to resolve 

3-10
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

most, if not all, of the technological challenges involved with catalyzing their entire product 

lines, with the exception of the replacement engines for the 4.3L and the 8.1L. 

NMMA and Mercury Marine stated that the phase-in approach suggested by EPA in the 

preamble is not a workable option for this industry. With thousands of boat builders dispersed 

across the U.S., marine engine manufacturers do not have ultimate control of the type of engines 

purchased and installed on boats. This is particularly the case where the engine manufacturer is 

still manufacturing engines that are not catalyzed. Boat builders determine which engines are 

purchased and can choose either catalyzed or non-catalyzed versions of the engines since boat 

builders are not subject to emissions standards. For these reasons, they concluded that a 

compliance deadline in model year 2010 for the majority of SD/I engines, with full 

implementation in model year 2011, makes sense in the context of this particular industry. 

NMMA summarized comments from its members of Four Winns Boats, LLC, 

Chaparral/Rodalo Boats, Massachusetts Marine Trade Association, Regal Marine Industry, 

Challenger Power Boats, Godfrey, Lowe Boats, Brunswick Corporation, North American 

Sleekcraft, S2Yachts, Sea Ray, Hallett, Cigarette Racing, Premier Marine Inc., and 

Larson/Glastron Boats. Two manufacturers urge EPA to adopt the third option for 

implementation: full compliance with the emission limits in 2010 for all the 4.3L & 8.1L and 

their replacements will have until 2011. Three manufacturers state engine supplier (Mercury 

Marine/GM) needs until 2010 to have all hp levels covered for national rule-if 2009, some 

models may be available for one year before phase-out. Four manufacturers commented the 

engines will need to be installed with onboard diagnostic emission notification systems - need 

time to engineer approach once receive engines from engine supplier. One commenter stated, as 

a small independent builder, the technology and the products to support this are clearly not 

available today and is pleading that the EPA will push this back until 2011 to allow for proper 

testing and implementation. Twelve commenters stated that California imposed requirement 

should be a testing ground until the system can be validated for a national release with a few 

years into the program. One commenter stated that the proposed implementation is not feasible 

due to changes being made in the availability of GM based engines which would result in some 

one year offering of motors and recommend gradual phase-in with full compliance by 2012. 

VolvoPenta supports full industry compliance with standards in 2010, except for 4.1 and 

supercharged 6.0 which need until 2011. This option keeps a level playing field for all small 

business partners and allows more time for California catalyzed units to acquire hours of actual 

operation in consumer hands. The option will provide adequate time for Volvo Penta to develop 

full model lines demanded by customers and ensures compliance to the rule. Volvo Penta needs 

additional time to conclude its own saltwater testing and to monitor the durability of California 

compliant engines. Volvo Penta stated that, if U.S. EPA proceeds with a rule requiring full 

industry compliance on January 1, 2009, with the standards for SD/I engines, then their 

comments are intended to serve as Volvo Penta’s application for a hardship exemption. 

Sea Ray advocated EPA to adopt, in the final rule, the third option for implementation 

discussed—full compliance with the emissions limits in 2010 for all SD/I engines except for the 

4.3L and 8.1L, and their replacements, which should have until 2011 to comply. Their engine 

supplier, Mercury Marine, is limiting model availability in CA for 2008 – 2009 and needs until 

3-11 
Chapter 3: Marine SI Engines 

2010 to have all of the Hp levels covered for a National Rule. If the 2009 date is implemented, 

Sea Ray commented that some of these models may only be available for a single year before 

being phased out. Moreover, since these engines will need to be installed with on board 

diagnostic emission notification systems, they will need time to engineer their approach in 

coordination with the products they receive from Mercury. Sea Ray also expressed its concerns 

about the robustness of catalyst systems in the salt water environment. Because testing was 

never completed, California will serve as a validation and feedback opportunity to all of the 

industry. The industry needs the additional time to understand what the problems might be 

should they arise. 

Mercury stated in a public hearing that if they had to meet the standard in 2009, as soon 

as the rule is signed, they would have to apply for relief under the hardship provision. Between 

the issues with GM that they have discussed, and the fact that they are not selling some models 

in CA, which they can not reconcile in their product line until 2010, Mercury stated that they 

need one of the options that is in the preamble. That option is compliance with the standard for 

the engine families that are not changing in 2010 and an extension to 2011 for the engine 

families being replaced by GM, keeping in mind that Mercury Marine will not get even 

prototype level hardware for GM's new engines until late this year or next year. According to 

Mercury, the development cycle for converting these auto base engines to marine engines is 30-

36 months. This also allows for the possibility of GM missing the launch date of the new models 

and the industry not having to come back to EPA for hardship relief. Mercury will also gain 

some field experience with the catalyst engines in the California market, as catalyst feasibility 

testing at SwRI was terminated, with industry approval, without ever demonstrating catalyst 

durability in a saltwater environment. Because that independent testing, funded by EPA and 

CARB, was never completed, Mercury commented that it is reasonable to allow for the 

California market to be that testing grounds for 2 years. Lastly, when asked about phase-in 

programs, Mercury stated that one of the issues that they have is that they do not control the 

product mix in the field, instead the boat builder does. However, Mercury does like the 

provisions in the proposed rule for banking early credits which is an incentive to get catalysts 

into the market early. 

California ARB strongly encourages U.S. EPA to adopt a 2008 start date of the 5 g/kWhr HC+NOx standard for sterndrive/inboard engines to avoid putting California dealerships at a 

competitive disadvantage with out-of-State dealerships that would still be able to sell boats 

without catalyst-equipped engines at a significantly lower purchase price (less the cost of catalyst 

and associated hardware). Tooling will already exist for the catalyzed engines as a result of 

California’s requirements, and an extra year to implement the same standards is unnecessary 

considering that the sole manufacturer already producing catalyst equipped engines for the 

California rule is doing so nationwide. Not only would nationally harmonized implementation 

eliminate the disparity in compliance costs between California and federal engines, it also makes 

sense from an economic perspective since the economies of scale (quantity discount) involved in 

producing a harmonized engine model nationwide rather than multiple state-based models would 

reduce the price of compliance both to the manufacturers and to the consumer. As EPA notes in 

the preamble, a sterndrive/inboard engine manufacturer that qualifies as a small business already 

offers a catalyst-equipped engine nationwide. Thus, the implementation delay and small volume 

manufacturer provisions proposed by U.S. EPA may be unnecessary, and would result in a delay 

3-12
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

in public health benefits. If U.S. EPA still believes it necessary to provide industry with some 

sort of compliance cushion, ARB suggested restructuring the federal program such that 2008 

models could be treated leniently in-use initially, providing industry with a greater learning 

opportunity for fine tuning their catalyst system designs, rather than a delay in implementing the 

5 g/kW-hr HC+NOx standard. 

New Jersey DEP commented that several CARB standards for exhaust emissions are 

fully phased-in between 2005 and 2008, whereas the proposed phase-in dates for the 

corresponding federal standards do not begin until 2010. Of most concern, the special provisions 

for small and medium manufacturers may delay full compliance until 2014. In light of the fact 

that manufacturers will already be providing cleaner engines and equipment to California and 

that technology issues will not be a factor, New Jersey DEP stated that these cleaner engines and 

equipment should be required to be made available sooner nationwide. 

MECA believes that the 2009 model year implementation date provides industry with 

adequate time to meet these standards. 

NACAA noted that sterndrive and inboard engines with catalysts are already in 

production and engine manufacturers are already tooled to produce catalyzed engines for 

California for 2008. Therefore, although they believe the proposed federal implementation 

schedule – beginning in 2009 – is appropriate and should not be delayed, they recommend that 

EPA require that once a certified engine is available in California it be sold nationwide. 

Pennsylvania DEP supports EPA’s proposed standards and implementation schedule for 

marine spark-ignition engines and vessels. 

NESCAUM supports EPA’s current proposal, that the SD/I catalyst-based exhaust 

emissions standards take effect in 2009, one year following implementation in California. They 

agree with EPA’s position that once the catalyst-based technology is introduced across product 

lines in California, it should be readily available nationwide soon thereafter. They see no need 

for EPA to implement the alternative approach of extending the compliance date to 2010. At the 

same time, as it appears that General Motors is discontinuing supplying the 4.3 and 8.1 liter 

engine blocks in 2009, they would not object to allowing additional time, as suggested, for the 

orderly transition to the 4.1 and 6.0 liter blocks. Their understanding is that the engines based on 

the 4.3 and 8.1 liter blocks represent a relatively small portion of the new marine engine market, 

compared to other more widely-used blocks. Presumably, the new 4.1 and 6.0 liter blocks will 

not claim a large share of the market, at least in their introductory years. Therefore, concluded 

commented that the overall emissions impact should be minimal if additional transition time is 

provided. They would support this approach (allowing additional time for engine blocks 

representing a small fraction of the market) over the alterative approach of allowing all engine 

families to certify to a more lenient transitional standard over the 2009-10 timeframe. 

New York DEC urges EPA to require implementation of the standards in 2009 for all 

engines. 

Wisconsin DNR commented that EPA shall require CARB certified sterndrive or inboard 

engines available in California from 2008 to be sold nationwide. 

3-13 
Chapter 3: Marine SI Engines 

Environmental Defense commented that EPA has proposed an implementation date for 

the SD/I exhaust emission standards of model year 2009. California’s HC and NOx standards 

take effect in model year 2008. Accordingly, the national standards will go into effect one year 

after the identical standards in CA. EPA observes that a “one year delay [in implementing the 

national rules] allows manufacturers adequate time to incorporate catalysts across their product 

lines as they are doing in California.” Environmental Defense strongly opposes any delay beyond 

this proposal. Indeed, one engine manufacturer is already selling engines equipped with catalysts 

nationwide. Reducing the HC, NOx and CO emissions from these small recreational boats will 

assist many states and local governments in achieving or maintaining healthy levels of ozone, 

PM and CO and will help to ensure better air quality for many Americans. 

Letters: 

Commenter Document # 

NMMA 0688 

Sea Ray 0683 

NJ DEP 0710 

Wisconsin DNR 0663 

NESCAUM 0641 

Environmental Defense 0648 

NACAA 0651 

Volvo Penta 0708 

Mercury 0693 

MECA 0668 

NY DEC 0659 

Pennsylvania DEP 0676 

Mercury (hearing) 0642 

Hallett 0713 

Sea Ray 0683 

S2Yachts 0697 

North American Sleekcraft 0666 

Brunswick Corporation 0695 

Lowe Boats 0660 

Godfrey 0645 

Challenger Power Boats 0644 

Regal Marine Industry 0635 

Massachusetts Marine Trade Association 0634 

Chaparral/Rodalo Boats 0630 

Four Winns Boats, LLC 0650 

Cigarette Racing 0637 

Premier Marine Inc 0613 

Larson/Glastron Boats 0626 

3-14
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

Our SD/I standards start to take effect with the 2010 model year, two years after the same 

standards apply in California. We believe a requirement to extend the California standards 

nationwide after a two-year delay allows manufacturers adequate time to incorporate catalysts as 

they are doing in California across all of their product lines. Once the technology is developed 

for use in California, it will be available for use nationwide soon thereafter. In fact, one 

company currently certified to the California standards is already offering catalyst-equipped SD/I 

engines nationwide. 

To address the challenge related to the transition away from the current 4.3 and 8.1 liter 

GM engines, we are adopting in the final rule a direct approval for a hardship exemption 

allowing manufacturers to produce these engines for one additional year without certifying them 

(see §1045.145). Starting in the 2011 model year, we would expect manufacturers to have 

worked things out such that they could certify their full product lineup to the applicable 

standards. 

3.2.3 Issues related to jet boats 

What Commenters Said: 

NMMA commented that the proposed definition includes jet boats in the SD/I category. 

72 Fed. Reg. 28,290. NMMA supports the inclusion of jet boats in the definition of SD/I engine 

with the condition that manufacturers of jet boats would receive until 2011 to comply with the 

more stringent SD/I emissions standards. Jet boats utilize the same engine technology as personal 

watercraft engines and have been regulated under the EPA standards applicable to personal 

watercraft and outboards. This technology is very different from SD/I engines, which rely on 

automotive-based engines. Additional lead time for compliance, therefore, is necessary to allow 

engine manufacturers sufficient time to redesign and develop engines—which typically takes 

three years for known technologies—that will comply with the new, more stringent SD/I 

emissions limits. It is inappropriate to subject jet boats to the same implementation lead-time as 

the SD/I engines considering that those manufacturers have been in product development for the 

2008 implementation of the CARB standards over the last few years. It is also critical that, as 

proposed, jet boats be allowed to average credits, both HC+NOx and CO, generated by other 

personal watercraft and outboards to provide flexibility and ensure that jet boats will be able to 

meet the SD/I emission standards. NMMA is supportive of the proposed approach discussed in 

the preamble and in the proposed regulatory text in § 1045.701(d) provided CO averaging is 

included. 

NMMA also stated that related to the inclusion of jet boats in the SD/I category is the 

treatment of the useful life for these engines. For PWC engines used in jet boats, NMMA 

supports a 5 year, 350 hour useful life. This is consistent with the proposed useful life for 

outboard and personal watercraft engines in the rule discussed below and is appropriate for jet 

boats given that the engines are identical. To force dual compliance levels for identical engines 

leads to confusion and increases the certification burden imposed on the engine manufacturer. 

NMMA also recommends that the useful life for jet boat engines be reviewed by EPA three years 

3-15 
Chapter 3: Marine SI Engines 

after the recommended model year 2011 compliance date and adjusted as experience is gained in 

the field with the unproven after treatment technology. 

BRP stated in a hearing and submitted written comments that they cannot support EPA's 

proposed catalyst based emission standards for stern drive and inboard engines as it presently 

applies to water-jet sport boats. This product category has been regulated under the standards 

applied to outboard and personal watercraft engines on the basis that water-jet sport boats utilize 

the same engine technology as personal watercraft engines. It is understood that the EPA now 

desires to regulate this boat category, which has exclusively utilized automotive-based engines. 

These sterndrive and inboard engine manufacturers have effectively been developing a catalyst 

solution in preparation for the CARB regulation since approximately 2004. It is therefore very 

inappropriate to subject the water-jet sport boats to the same proposed lead-time given the 

difference in basic engine technology and prior catalyst development time. 

Furthermore BRP commented there are numerous patents held by a competitive water-jet 

sport boat manufacturer which represent clear and significant design constraints to BRP in order 

to avoid patent infringement. There are effectively 30 related patents which have applicability to 

water-jet sport boats, 13 which have specific catalyst application constraints. These constraints 

include catalyst positioning, layout, cooling and sensor placement issues. The fundamental 

nature of these challenges results in the need for greater development lead-time. 

BRP development and application lead-time for an established engine technology is 

approximately three years. The patent issues they have briefly explained represent complex 

design challenges and it is therefore not possible at this point to project the amount of additional 

development time required to meet the proposed catalyst application to water-jet sport boats. 

BRP also stated that however, the lead-time challenge can be justly addressed by 

providing water-jet sport boat manufacturers which utilize an outboard personal watercraft 

engine technology the following allowances: 

1. An implementation lead-time of model year 2011, and 

2. BRP is supportive of the proposed corporate averaging provisions in 40 CFR 

1045.701 (d) which allow "Sterndrive / Inboard engines certified under 1045.660 for 

jet boats may be use HC + NOx exhaust credits generated from outboard and personal 

watercraft engines, as long as the credit-using engine is the same model as an engine 

model from an outboard or personal watercraft family." For the corporate averaging 

provision of 40 CFR 1045.701 (d) to be meaningful to a manufacturer, CO averaging 

is essential for achieving compliance. (also listed in 3.6.2) 

Yamaha stated in a hearing, after considerable discussions with their engineers to reach a 

feasibility consensus they request that if the EPA were to agree on a MY start date of 2011 

(which again for Yamaha is April of 2010) for compliance at the Inboard level of 5 g/kW-hr, this 

would afford additional time to an already taxed staff, to design and build a "ground up engine" 

required to meet the target levels presented in the proposal. As the EPA may be aware, PWC 

engines utilized in Jet boats is a very small quantity, and short runs of catalyst based engines 

would be cost prohibitive. Therefore, this short additional lead time will have the positive effect 

of bringing into a lower compliance level, a greater amount of PWC engine families to help 

3-16
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

offset production costs. Again by allowing this lead time, the EPA will have championed even 

further emission reductions over the broad engine spectrum. 

In Yamaha’s view, a MY 2011 compliance date (although aggressive) was agreed upon 

internally as this appears to parallel what the EPA has considered acceptable lead time for the 

SD/l members affected by this rule as a result of new engine block design and feasibility issues. 

If the industry is in fact subject to classify PWC engines used in Jet Boats as a different engine 

then we need the additional lead time. 

Yamaha submitted written comments stating the proposed definition includes Jet boats 

into the SD/I Category. Yamaha utilizes PWC engines (complete exact units) to propel their Jet 

boat product. The number of units used currently does not quite come to 8% of their entire PWC 

engine production, Yamaha will most likely by defacto have to produce en mass a compliant 5gr 

engine that will carry the day for both PWC and Jet Boat compliance. By allowing additional 

requested lead time this will in actuality further reduce emissions over a larger engine group. 

Even though this is an engine rule and should remain so, Yamaha will support this 

reclassification if the following flexibilities are granted or represented within the rule. 

a. Enough lead time to develop, test and produce the necessary engine block, exhaust 

and catalyst systems required to achieve a 5gr level of HC+Nox emission and 75gr 

CO levels as proposed for SD/I engines. Yamaha estimates this to be achievable in 

M/Y 2011 which is reflective of the proposed lead time flexibility being requested by 

the SD/I engine suppliers due to the engineering challenges of a ground-up new 

engine block w/ catalyst being produce as a replacement to current available units. 

b. Yamaha commented that language to exclude 75gr. CO requirement on PWC engines 

utilizing banked HC+NOx credits for Jet Boat reclassification compliance (between 

M/Y2009 and 2011) should be included in the rule as no banking of CO credits 

existed on previous Tier 1 requirements and currently are above the 75gr limit set for 

a catalyzed SD/I automotive based engine. 

Yamaha requests that the useful life period for Jet Boat engines be the same as current 

PWC useful life of 5 years or 350 hours as these engines share same design and product use and, 

upon completion of a successful EPA technical review in 2014 raise the useful life period to that 

of SD/I. This would allow for proper long term durability testing of catalysts systems that would 

need to be in place. This request is not a large departure than the EPA seeking comment on the 

proposed reduced useful life structure of the High Performance SD/I engines. Yamaha strongly 

requests for PWC engines used in Jet Boats be granted similar flexibility and remain at the same 

useful life period as our PWC engines. 

Mercury Marine stated that EPA is proposing to define “sterndrive/inboard engine” in § 

1045.801 as “a spark ignition engine that is used to propel a vessel, but is not an outboard engine 

or a personal watercraft engine. This includes engines on propeller-driven vessels, jet boats, air 

boats, and hovercraft.” 72 Fed. Reg. at 28,290 (emphasis added). Mercury Marine has no 

objections to creating a single term that would include both sterndrive and inboard engines in a 

single category of engines and that also clarifies that hovercraft and air boats are specifically 

included in this engine category. However, it is also critical that, as proposed, jet boats be 

allowed to utilize credits, both HC+NOx and CO, generated by outboards to provide flexibility 

3-17 
Chapter 3: Marine SI Engines 

and ensure that jet boats will be able to meet the SD/I standards. (also listed in 3.6.2) In addition, 

Mercury recommends that the new SD/I standards for jet boats become effective in 2011. 

Yamaha asked whether the requirement to have smaller sales of jet boat engines than the 

analogous outboard or personal watercraft engines needed to be in place for every model year. 

The concern related to a scenario in which the outboard and personal watercraft versions of an 

engine would be discontinued while the jet boat engines would continue in production for 

another year. 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Yamaha 0721 

Mercury 0693 

Yamaha (hearing) 0642 

Bombardier (hearing) 0642 

Our Response: 

We are providing some flexibility in meeting new emission standards for jet boat engines 

because they are currently designed to use engines derived from OB/PWC applications and 

because of their relatively low sales volumes. We will finalize the proposal to allow 

manufacturers to use emission credits generated from outboard and personal watercraft engines 

to demonstrate that their jet boat engines meet the new HC+NOx standards for SD/I engines. 

We are also adding the flexibility of CO emission averaging that was not previously included in 

the NPRM. This is necessary to fulfill the intent of the proposed flexibility. 

Manufacturers of jet boat engines subject to SD/I standards and using credits from 

outboard or personal watercraft engines must certify these jet boat engines to an FEL that meets 

or exceeds the standards for outboard and personal watercraft engines. We are providing 

manufacturers a one year delay to meet the FEL requirement which now becomes effective in 

2011. 

Jet boat engines are now by definition sterndrive/inboard engines, so the default useful 

life period is 10 years or 480, whichever comes first. However, we understand that jet boat 

engines that are common to personal watercraft or outboard engine models depend on the 

preexisting certification demonstration. As such, we believe it is appropriate to allow for a 350-

hour useful life so that the original certification can continue to be valid without additional 

durability demonstration for the jet boat engines. This shorter useful life does not apply for jet 

boat engines that are certified independently. Note that, under 1045(3)(2), any SD/I engine 

manufacturer may request that we approve a shorter useful life on a case-by-case basis. 

We understand that there are valid business reasons to discontinue engine models in 

stages for certain applications. We believe the regulations should address Yamaha’s concern, 

especially because their plan involves a long-term strategy to design their jet boat engines to 

3-18
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

comply with the SD/I standards without relying on emission credits. We have revised this 

provision such that it no longer requires a demonstration of lesser sales of jet boat engines for 

every model year. This would allow us to respond to a special situation such as that described by 

Yamaha and acknowledge that their situation meets our intent. We would expect such a 

demonstration rarely to be based on sales information from more than two consecutive model 

years. 

3.3 OB/PWC standards and lead time 

3.3.1 OB/PWC standards–level and form of standard 

What Commenters Said: 

NMMA and Mercury Marine commented for outboard (OB) and personal watercraft 

(PWC) engines in § 1045.103, EPA is proposing a HC+NOx standard of 28 - 0.3 x P g/kW-hr for 

engines <= 40 kW. For engines > 40 kW, EPA is proposing 16 g/kW-hr for HC+NOx. 72 Fed. 

Reg. at 28,262. EPA explains in the preamble that the HC+NOx standards are similar in 

stringency to the 2008 model year California limits but use a “simplified form” as opposed to the 

one used by the CARB regulations. 72 Fed. Reg. at 28,130. While NMMA appreciates efforts to 

simplify a regulatory requirement, the best approach for emissions standards for the PWC and 

OB engine categories is to harmonize any new federal standards exactly with those in place in 

California. To establish a separate formula for developing the federal number, even if it is similar 

in stringency, creates additional complexity for the marine industry with no environmental 

benefit. 

NMMA and Mercury Marine continued that with respect to CO emission limits, EPA is 

proposing in § 1045.103 for engines = 40 kW, a standard of 500 – 5.0 x P g/kW- hr, and for 

engines > 40 kW, a standard of 300 g/kW-hr. The proposal also would allow manufacturers to 

average, bank and trade emission credits and would require a family emission limit (FEL) for 

engines > 40 kW at a maximum of 450 g/kW-hr. The maximum value for the FEL for all other 

engines would be a formula of 650 – 5.0 x P. 72 Fed. Reg. at 28,263 (proposed § 1045.103(b)). 

These proposed CO levels are technologically achievable and assure that PWC and OB engines 

will be able to still meet the CARB 2008 HC+NOx emission standards. From a safety 

perspective, these levels are also appropriate. USCG boating safety statistics for deaths from CO 

poisoning clearly indicate that PWC and OB engines have no history of CO poisoning. A more 

stringent standard would impose a significant cost burden on these manufacturers with no health 

or welfare benefits as evidenced by the science and accident statistics associated with CO 

poisoning. Thus, NMMA supports these standards in the proposal and agrees that if EPA is to set 

a limit for CO, these levels are appropriate for these two engine segments. 

Mercury Marine commented that EPA has requested comment on catalyst level emissions 

on OB/PWC. Mercury Marine is the only OB company that has to meet the CA SD/I catalyst 

level emissions standard for 2008. Since they have been developing catalyst systems for SD/I, 

Mercury states that they are in the best position to comment on this. For SD/I engines, where 

weight and packaging are much less of an issue, the cost to develop catalyst engines is in the 

vicinity of $3M per engine family. The engineering challenges to deal with water intrusion, 

condensation, exhaust gas temperatures, etc. have been enormous. 

3-19 
Chapter 3: Marine SI Engines 

Mercury Marine continued that for Outboards, these challenges, and the associated costs, 

are more extreme. Due to the tight packaging, under cowl thermal management, and closer 

proximity to water, catalysts on outboards will be a larger, and more expensive, undertaking, and 

technical feasibility is not a given. It will entail a complete redesign of every outboard engine 

and, if technically feasible, will cost in the range of $8M – 15M per engine family, just in 

engineering costs, and take 4 – 5 years after a rule is finalized to launch the first models. Any 

such rule can not be finalized until technical feasibility is established. Therefore, it is 

inappropriate to consider catalyst level emissions on outboards at this time. 

Honda commented on the Outboard and Personal Watercraft (PWC) Exhaust Standard 

Proposal. They suggest that EPA use the CARB’s equation when setting the exhaust emission 

standard for outboard engines. Emission standards in the proposal’s Section 1045.103 are 

described in the preamble as “simplified”. Honda believes that they are not “simplified”, but 

simply different with no real reason or environmental benefit. The proposed standard diverges 

from the original EPA standards curve and the California standard creating, not a simplified 

uniform standard for the United States, but rather two separate standards. 

Bombardier commented that EPA explains these standards are of similar stringency to the 

CARB 2008 standards (3-Star), but are in a simplified form. However, creating a new standard 

different from the California standard complicates certification. BRP urges harmonizing the 

proposed HC +NOx exhaust emissions standards for PWC and Outboards with the CARB 3-Star 

emission standards. 

Suzuki appreciates EPA's attempt to simplify the certification process wherever possible; 

however EPA's direction with the proposed HC+NOx standards creates a situation where some 

outboard engines currently certified to comply to CARB 2008 standards will require calibration 

and design changes to comply with the slightly different levels proposed by EPA while still 

maintaining reasonable compliance margins . This will be an expensive and resource-intensive 

effort which will not be of benefit to the environment. It is also important to note that the effort 

required to calculate the appropriate emission standard for a given engine family is not materially 

different between EPA's proposal and the CARB 2008 HC+NOx requirements. Considering that 

the rational for the proposed new Federal-specific HC+NOx standards is to simplify the 

certification process, and the actual effect will be to increase certification cost and effort, it is not 

reasonable for EPA to proceed with their proposed federal-specific HC+NOx standards. Suzuki 

requests EPA reconsideration of their proposal to create new Federal-specific HC+NOx emission 

standards, and requests EPA adopt a requirement that strictly harmonizes with the CARB 2008 

HC+NOx standards. 

Suzuki continued that EPA has proposed all-new CO standards of 500 - 5 .0 x P g/kW-hr 

for engines <40kW, and a standard of 300 g/kW-hr for engines of >40 kW. Additionally, EPA 

has proposed to limit maximum emissions of CO to levels of 150 g/kW above the applicable 

standard. Suzuki believes EPA's proposal represents levels that are technically achievable given 

reasonable lead-time and will allow for continued compliance with CARB 2008 HC+NOx 

standards without major design changes. However, EPA's proposed CO standards will require 

design changes and development for some Suzuki outboard engine families. Assuming that EPA 

3-20
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

harmonizes with the CARB 2008 HC+NOx standards and a reasonable amount of lead-time is 

provided, Suzuki can support EPA's new CO standards as currently proposed. 

Tohatsu stated in a hearing that contents of the new regulations should be the same as the 

current CARB standards to avoid having to comply with two different sets of standards and 

testing methods. They would like to see one national standard rather than a national standard and 

then also other standards set by different local areas. 

California ARB supports adoption of a federal 16 grams per kilowatt-hour (g/kW-hr) 

hydrocarbon plus oxides of nitrogen (HC+NOx) standard for outboard/personal watercraft 

engines greater than 40 kilowatt (kW). This standard is technologically feasible and is similar in 

stringency to the existing 2008 California standards for the majority of the category. 

California ARB also supports U.S. EPA’s proposed carbon monoxide (CO) standards for 

outboard/personal watercraft and sterndrive/inboard engines. These standards are technologically 

feasible. ARB staff will likely propose the adoption of identical CO standards when it next 

revises California’s regulations for recreational marine engines. 

NESCAUM supports EPA’s effort to harmonize the federal emissions standards with 

those standards already adopted in California. In many respects, the proposed federal standards 

are identical to or analogous with California standards. This approach will make it easier for the 

engine and equipment manufacturers to provide 50-state products to the U.S. market. 

Environmental Defense supports EPA’s proposal to establish more stringent HC and 

NOx emission limits for outboard and personal watercraft (O/PW). The proposed standards, if 

implemented, would achieve more than a 60% reduction in HC and NOx emissions over existing 

standards. These standards are consistent with those previously adopted by CARB. 

Manufacturers will be able to achieve these emissions reductions by replacing older carbureted 

two-stoke engines with more advanced, direct injection two-stroke or four-stroke engines. This 

transition should be relatively easy and inexpensive for manufacturers as the market trend has 

been moving toward the retirement of carbureted two-stoke engines in favor of cleaner two and 

four-stroke engines. Environmental Defense is also pleased that EPA’s proposal includes a CO 

limit for OB/PWC engines. Achieving the proposed CO standard is readily achievable as the 

same two and four-stroke engines required to meet the HC and NOx standards will achieve the 

CO standard. 

NY DEC stated that EPA proposes to adopt standards generally similar to existing 

California standards, yielding a 60% reduction in combined hydrocarbon and NOx emissions 

compared to current federal standards. The Department supports these proposed standards. 

NY DEC also stated that additional work is needed to facilitate the application of catalysts to 

outboard and personal watercraft engines, many of which are automotive sized. 

NACAA commented with respect to personal watercraft and outboard engines, they 

support the proposed standards for implementation in 2009. They note that EPA anticipates 

manufacturers will meet these standards with readily available technology – improved fueling 

systems and other in-cylinder controls – and, therefore, question why the agency did not assess 

3-21 
Chapter 3: Marine SI Engines 

the feasibility of catalysts for these engines, for the purpose of pursuing future, more rigorous 

catalyst-based standards. They recommend that the agency conduct such an analysis and proceed 

with additional standards accordingly. 

Pennsylvania DEP supports EPA’s proposed standards and implementation schedule for 

marine spark-ignition engines and vessels. Since the standards proposed for personal watercraft 

and outboard engines appear to be easily achieved by manufacturers, DEP urges EPA to assess 

the feasibility of additional technology for the future as quickly as possible. 

MARC AQ Forum stated that EPA should investigate the feasibility of using catalysts to 

reduce emissions from personal watercraft and outboard engines. If such technology proves 

workable, EPA should move expeditiously to set more stringent emissions standards for these 

engines. 

SCAQMD staff believes that more stringent catalyst based standards are appropriate for 

this category. The California Air Resources Board staff in developing the outboard/personal 

watercraft standards in 1998 identified catalyst based technology as one of the possible 

technologies to meet the proposed standards. Their analysis showed that challenges in bringing 

catalyst technology to marine engines existed, but concluded that they were not insurmountable. 

Consistent with this conclusion, the California Air Resources Board proposed state strategy 

measure will require new outboard and personal watercraft engines to meet a 5.0 g/kW-hr by 

2013 (approximately three (3) times lower than the U.S. EPA currently proposed standard). This 

level of control is expected to be reached using catalyst based technology. Review of the Draft 

Regulatory Impact Analysis document also shows that currently one personal watercraft 

manufacturer has certified engines equipped with an oxidation catalyst, demonstrating that 

catalyst based technology is feasible. Therefore, they believe that a more stringent catalyst based 

standard beginning in the 2013 timeframe is appropriate and they strongly urge EPA to consider 

adopting this additional standard (i.e., 3 to 5 g/kW-hr) for the outboard/ personal watercraft 

category as a second phase of catalyst based standards. 

Wisconsin DNR requested EPA to assess the feasibility of more stringent catalyst-based 

emission standards for personal watercraft and outboard engines. 

3-22
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

Honda 0705 

South Coast AQMD 0704 

Wisconsin DNR 0663 

NY DEC 0659 

Environmental Defense 0648 

NACAA 0651 

Bombardier 0674 

Mercury 0693 

MARC AQ Forum 0696 

Suzuki 0698 

CARB 0682 

Pennsylvania DEP 0676 

Tohatsu (hearing) 0642 

Yellowfin 0681 

Our Response: 

Section 213(a)(3) of the Clean Air Act specifies the criteria EPA needs to consider in 

revising existing emission standards. Revised emission standards are to achieve the greatest 

degree of emission reduction technologically achievable taking into consideration the cost of 

technology in the lead time available to manufacturers, as well as noise, energy and safety 

factors. Given these criteria, EPA continues to believe that the proposed OB/PWC standards are 

the appropriate standards for these engines for the years in which they were proposed. These 

standards can be met through the expanded reliance on four-stroke engines and two-stroke 

direct-injection engines. 

Based on industry input, we understand that our proposed simplification of the form of 

the HC+NOx standard would cause undue complexity for industry. Therefore, we will be 

finalizing a HC+NOx standard that utilizes a functional relationship to set the emission standard 

for each engine family depending on the power rating, common with the CARB 2008 emission 

standards. The final HC+NOx standard is roughly equivalent to the proposed standard, in terms 

of stringency, and will achieve more than a 60 percent reduction from the existing 2006 

standards. 

 We will finalize the proposed CO emission standards for OB/PWC engines. These 

standards will result in meaningful CO reductions from many engines and prevent CO from 

increasing from engines that already use technologies with lower CO emissions. The new 

emission standards are largely based on certification data from cleaner-burning Marine SI 

engines, such as four-stroke engines and two-stroke direct-injection engines. 

We believe the catalyst technology that will be required to meet emission standards 

substantially more stringent than we are adopting has not been adequately demonstrated for 

outboard or personal watercraft engines. Outboard engines are designed with lower units that are 

3-23 
Chapter 3: Marine SI Engines 

designed to be as thin as possible to improve the ability to turn the engine on the back of the boat 

and to reduce drag on the lowest part of the unit. This raises concerns about the placement and 

packaging of catalysts in the exhaust stream. As such, we believe the new standards for 

HC+NOx and CO emissions are the most stringent possible in this rulemaking. While there is 

good potential for eventual application of catalyst technology to outboard and personal 

watercraft engines, we believe the technology is not adequately demonstrated to determine 

whether or when such technology would be available. More time to gain experience with 

catalysts on sterndrive and inboard engines and a substantial engineering effort to apply that 

learning to outboard and personal watercraft engines may allow us to pursue more stringent 

standards in a future rulemaking. 

3.3.2 OB/PWC standards–lead time 

What Commenters Said: 

NMMA and Mercury Marine commented that EPA’s proposal has model year 2009 as 

the implementation date for the proposed HC+NOx and CO standards, including the FEL caps, 

for PWC and OB engines. 72 Fed. Reg. 28,262 (proposed § 1045.103). One calendar year lead 

time to comply with the federal emissions standards and the FEL caps is simply not workable for 

these engine segments because of the nationwide scope of the standards. Although these 

manufacturers will have some families that will meet the model year 2008 compliance date in 

California, a national rule (with fleet-averaging and FEL caps) in model year 2009 would 

disallow the sale of older, carbureted 2-stroke engines and would force these companies to reengineer their entire product line. In turn, this would have a major impact on existing signed 

supply agreements with small boat builders which will lead to product shortages and disrupted 

business plans. The implementation of a national rule is a considerable undertaking that cannot 

be achieved in one year. Assuming that the rule is signed by the end of 2007, manufacturers will 

not see a rule published until early 2008. This means that some manufacturers could be starting 

production of model year 2009 PWC and OB engines at the same time a final rule is published. 

Even if a final rule is signed and published by the end of 2007, there is less than a one-year lead 

time for manufacturers. NMMA requests that EPA extend the implementation date for PWC and 

OB engines until model year 2010 and delay the imposition of FEL caps for PWCs until model 

year 2011. This results in the industry being able to meet the standards (with fleet averaging) in 

model year 2010, and gives industry an additional year to re-engineer the remaining PWC engine 

families that might be subject to FEL caps. Individual NMMA members will provide additional 

support in their separate comments as to why the additional delay of the FEL cap for PWCs is 

warranted. 

NMMA and Mercury Marine continued to state that a two-year period for 

implementation is well supported by several EPA rules promulgated pursuant to its authority in 

CAA § 213. For example, for Recreational Vehicles, EPA provided a four year lead time and 

allowed for a phase-in. See Control of Emissions from Nonroad Large Spark-Ignition Engines, 

and Recreational Engines (Marine and Land-Based), Final Rule, 67 Fed. Reg. 68,242 (Nov. 8, 

2002). In addition, for the first marine engine standards for PWC and OB engines, EPA provided 

industry with a two year lead time from the time of promulgation of the standards until the first 

implementation date for the emissions standards. See Control of Air Pollution; Final Rule for 

3-24
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

New Gasoline Spark Ignition Marine Engines; Exemptions for New Nonroad Compression 

Ignition Engines at or Above 37 Kilowatts and New Nonroad Spark Ignition Engines at or Below 

19 Kilowatts, Final Rule, 61 Fed. Reg. 52,087 (Oct. 4, 1996). As an alternative, EPA can draft 

the implementation date as two years from the date of publication in the Federal Register to 

ensure that a two-year lead time is preserved. 

NMMA suggested that another approach that also would assist manufacturers in 

transitioning to a national standard is a phase-in of 50 percent in model year 2009 and the 

remaining 50 percent in model year 2010 and a delay of the FEL cap until model year 2011 for 

PWCs. Unlike the SD/I engine category, which is a very different market with unique 

distribution and sales arrangements, a phase- in approach for implementation is well-suited for 

the PWC/OB market. This would allow manufacturers to phase out carbureted 2 stroke engines 

and provide additional time for redesign and development of engines that can comply with the 

standards. EPA used a similar 50-50 percent phase-in for Phase I of the standards for 

Snowmobiles in the Recreational Vehicle Rule. See 40 C.F.R. §1051.103. 

Mercury Marine also requests that EPA phase-in the OB standard between 2009 and 

2010. Their recommendation is to allow 10% of the manufacturer’s carryover product line to be 

excluded from the FEL caps in 2009. These units would still be required to utilize credits to meet 

the standard. They believe that there is no need for any exclusions, or modifications, in credit 

use or calculations. Starting in 2009, all Outboards would switch over to the new credit 

calculations in the new rule. Carryover credits from the current rule would still be useable for 3 

years. Further, in order to not have to recertify most of the product line in just a few months, the 

final rule should allow carryover certifications, conducted under the requirements of the current 

rule, to be used until recertification of the product is required for other reasons. 

Yellowfin commented that they are a low volume builder of high end offshore center 

console outboard boats. They commented that it is imperative for them to have ample supply of 

a variety of engines (2-stroke and 4-stroke). EPA’s proposal that outboards meet the CARB 

2008 standards nationally in 2009 would impact their business severely. They recommended 

that the CARB 2008 standards should be implemented nationally in 2010. 

Honda requests that the effective date for compliance be extended to 2010 and not be 

2009. They stated that EPA has proposed a 2009 implementation date for outboard exhaust 

emissions and outboard fuel lines. Honda will have certified and begun production of engines for 

the 2009 MY before this regulation is projected to be finalized. It will be quite difficult to certify 

and produce product with this negative lead time. However, they do believe that it will be 

possible to exhaust certify engines beginning in the 2010 model year. 

 Bombardier commented that provided EPA adopts the current 3-Star California exhaust 

emission standard for PWC and Outboards, BRP can fully comply with this standard in MY2009 

if EPA allows carry-over data to be used. 

Suzuki stated that although their full outboard engine product line is currently certified to 

the 2008 CARB HC+NOx standards, implementation of EPA's new proposed CO standards will 

require design changes to some Suzuki models to ensure that emissions of HC+NOx and CO are 

3-25 
Chapter 3: Marine SI Engines 

attained with sufficient compliance margin. Considering that production of 2008 models has 

already begun, EPA's proposed 2009 model year effective date will provide less than one year of 

lead-time which is insufficient for engine families that require changes from their 2008 model 

year configuration. As discussed above and assuming harmonization with CARB 2008 

HC+NOx levels, compliance with the new CO standards proposed by EPA will require 

development effort for some Suzuki models. Therefore, Suzuki requests EPA adopt a 

70%/100% phase-in of the new HC+NOx and CO standards for the 2009 and 2010 model years 

to allow for a reasonable development process. 

Yamaha stated in a hearing that in the preamble, EPA has proposed to implement a start 

date of Outboard and PWC exhaust emission levels in MY 2009. To Yamaha, Model Year 2009 

would mean compliance as of April, 2008 production which may come and go without signage 

of this very rule. Due to the protracted direction and ever dynamic time frames experienced with 

this NPRM, their Engineering and product planning staff are respectfully requesting that in order 

for Yamaha to re-evaluate their current model line-up, readjust the mapping and fuel calculation 

of current 4 stroke technology required to achieve a lower emission level across our product line 

and to be allowed to utilize our emission credits earned in 2006, 2007 and 2008 Tier I, an 

additional 1 model year lead time will be needed. 

Yamaha continued to comment that this would be MY 2010 which for Yamaha would be 

production starting April of 2009. At this point all elements of the emission levels including the 

FEL cap within this proposal would go into effect. This in essence would disallow the sale of 

all carbureted 2 stroke engines from this point on, achieving one of EPA's objective goals. 

Yamaha commented that the implementation dates outlined in the proposal reflect a 

Compliance Date of M/Y (model year) 2009. For Yamaha this would mean compliance for their 

line up of 25 engine families by April of 2008 production start period. That is if the rule is even 

signed on a time frame prior to this date. Yamaha recognizes the EPA is aware of compliant 

engines in California under the California ARB mandates but that quantity and models sold in 

CA is very small compared to a 50 state basis (10 families vs. 25 nationally). Yamaha has over 

200 different model variations to supply the marine industry with appropriate designs and use 

characteristics for the boating public. It is their position that the M/Y 2009 is unreasonable and 

unobtainable for Yamaha based on many factors. Their current facility is working at and beyond 

peak output to supply a world market. To affect new mapping and fuel calibrations to any 

already taxed system will not be achievable in the proposed time period. 

Yamaha continued to comment that another area affected by the proposed dates is long 

term supply contracts to many boat builders in the US that in their long term planning pre-existed 

EPA action and could not foresee a start date of this proposal. Due to its dynamic nature, to 

incorporate the necessary changes in boat design (flotation and transom strength) and sales 

structure is impossible for 2009. If Yamaha cannot continue to supply these engines currently 

being used by the builders a product shortage will occur causing business disruption to very 

small business owners and many parties face potential litigation for breech of contract. 

Yamaha also stated that US protectorates and isolated attainment states (example Hawaii, 

Puerto Rico) fall under EPA reach but are supplied by our factory in Japan with product. These 

3-26
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

regions due to their remote locations have not embraced (both for technology infrastructure and 

cost reasons) new technology in regards to outboard product but, Yamaha USA must list these 

units in our product certification process and numbers. 

Yamaha commented that as the EPA can realize, they have a monumental task ahead of 

them to achieve compliance even if allowed 3 years lead time. Yamaha also realizes that they 

can bring forward certain engines that can meet the new emissions levels as demonstrated by 

their compliance in CA. With this knowledge Yamaha is requesting that if the EPA cannot see 

the need to hold off starting exhaust emission compliance until M/Y 2010 then they propose a 

phase in amount of 50% of compliant engines (based on total engine sales) in 2009 with 50% 

exemption with no FEL or NTE caps and achieve 100% compliance in Model Year 2010 with all 

caps in place. This extra year is consistent with lead time flexibilities allowed in other EPA 

rulemakings. 

NMMA member companies such as Ranger Boats, Triton, Premier Marine Inc., 

S2Yachts, Lund Boat Co, Brunswick Corporation, Brunswick Commercial and Government 

Products, Inc., Lowe Boats, Godfrey, Challenger Power Boats, Cigarette Racing, Massachusetts 

Marine Trade Association submitted comments to the proposed rule. Fourteen equipment 

manufacturers support 2010 (or later) for outboards due to the fact that outboard manufacturers 

were planning their new OB engine designs for 2010 and moving implementation to 2009 would 

result in some engine designs not being available for about one year. In order to remain 

competitive and assure a smooth transition, they need to have engine designs available. Some 

companies have international business and reputations that are needed to maintain for success. 

Some companies work on smaller margins and need all engine designs to be available. One 

manufacturer stated their desire for a gradual phase-in with full compliance by 2012. 

Tohatsu stated in a hearing that it is quite a tough job for a small manufacturer like 

Tohatsu who has total employees of less than 500 people to re-develop and set calibration fuel, 

ignition timing, etc. and also comply with evaporation requirements. And naturally these 

changes will also require a new batch of deterioration testing at 350 hours for all models. 

Sea Ray commented that in the rule, it is proposed that OB engines be compliant to the 

CARB 2008 emission standards by 2009. It is understood that OB manufacturers have been 

preparing for this changeover but with a 2010 target date in mind. Although it appears that most 

engines will comply by 2009, having this extra transitional year will be beneficial to all 

concerned. If the implementation date is accelerated to 2009, there may actually be some 

outboard model engines that will no longer be able to be sold in the United States. The industry 

currently faces enough issues regarding sales of boats in these use categories. 

NACAA commented that with respect to personal watercraft and outboard engines, they 

support the proposed standards for implementation in 2009. 

Pennsylvania DEP supports EPA’s proposed standards and implementation schedule for 

marine spark-ignition engines and vessels. 

3-27 
Chapter 3: Marine SI Engines 

CARB recommends that U.S. EPA revise the implementation date for this standard to 

begin in 2008 rather than in 2009 as proposed. Although slight, the potential exists for unfair 

competition between California dealerships and out-of-State outboard/personal watercraft 

dealerships that would be permitted to sell higher emitting, but less expensive, outboard/personal 

watercraft engines in 2008. ARB believes that sufficient flexibility already exists in federal 

regulations (e.g., 40 CFR 1068.240, 245, or 250) to address the compliance concerns mentioned 

in the preamble for manufacturers, if any, that do not sell outboard/personal watercraft engines in 

California and which because of this, may need more time to comply with the proposed standard. 

NJ DEP commented that specifically, several CARB standards for exhaust emissions are 

fully phased-in between 2005 and 2008, whereas the proposed phase-in dates for the 

corresponding federal standards do not begin until 2010. Of most concern, the special provisions 

for small and medium manufacturers may delay full compliance until 2014. In light of the fact 

that manufacturers will already be providing cleaner engines and equipment to California and 

that technology issues will not be a factor, these cleaner engines and equipment should be 

required to be made available sooner nationwide. 

Environmental Defense commented that EPA is proposing to implement the O/PW 

standards in model year 2009. California’s comparable HC and NOx emissions standards take 

effect in model year 2008. While Environmental Defense agrees with EPA that it is feasible to 

implement these standards nationally one year after CARB’s take effect, they see no reason why 

the standards cannot be implemented in 2008. As EPA notes in its explanation for this near-term 

implementation date, many manufacturers are already selling lower emission engines that meet 

the CARB HC and NOx standards nationwide. These manufacturers will not need to do 

anything in order to comply with the proposed federal O/PW standards. Therefore, they urge 

EPA to better explain its reason for the 2009, as opposed to 2008, implementation date. 

3-28
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

Sea Ray 0683 

Honda 0705 

NJ DEP 0710 

Environmental Defense 0648 

NACAA 0651 

Bombardier 0674 

Yamaha 0721 

Mercury 0693 

Suzuki 0698 

CARB 0682 

Pennsylvania DEP 0676 

Yamaha (hearing) 0642 

Tohatsu 0642 

Ranger Boats 0628 

Triton 0656 

Premier Marine Inc., 0613 

S2Yachts 0697 

Lund Boat Co 0655 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products, Inc. 0652 

Lowe Boats 0660 

Godfrey 0645 

Challenger Power Boats 0644 

Cigarette Racing 0637 

Massachusetts Marine Trade Association 0634 

Our Response: 

We have considered the many comments we received supporting our proposed OB/PWC 

timing or arguing for different timing. Several air quality agencies and environmental 

organizations argued that earlier implementation of technologies is feasible. Many manufacturers 

commented that they will require an additional year to make their entire lineups compliant with 

the national rule. 

We have considered the time required by the industry to complete the necessary design, 

development, and validation activities for their product lines, and have concluded that 2010 is the 

appropriate date for the new emission standards of OB/PWC engines. The option suggested by 

commenters for a 50/50% phase-in for 2009 and 2010 was not a feasible option because the rule 

will not be signed until after the 2009 model year begins. Essentially this phase-in would have 

allowed them to sell carbureted two-stroke engines for an additional year beyond the proposed 

implementation dates. The majority of the remaining engines can meet the new standard either 

directly, or through credit exchanges. By delaying the implementation date to 2010, 

manufacturers still have the additional year of lead time requested, beyond the proposed 

3-29 
Chapter 3: Marine SI Engines 

implementation date, to phase-out carbureted two-stroke engines. The final rule gives two years 

beyond the implementation date of the California standards of similar stringency. In addition to 

phasing-out carbureted two-stroke engines, manufacturers may need additional time to refine 

emissions calibrations for engines not currently sold in California. The additional time will give 

manufacturers time to address any models that may not meet the upcoming California standards 

or are not sold in California. This also accommodates the lead time concerns with the timing of 

this final rule as expressed by the commenters. 

The new exhaust emission standards represent the greatest degree of emission control 

achievable in the effected time frame. While manufacturers can meet the standards with their 

full product line in 2010, requiring full compliance with a nationwide program earlier, such as in 

the same year that California introduces new emission standards, will pose an unreasonable 

requirement for manufacturers to develop entire product lines compliant with the new standards 

with little to no lead time. Allowing two years beyond California’s requirements is necessary to 

allow manufacturers to certify their full product line to the new standards including the 

additional CO requirement, not only those products they will make available in California. 

3.4 High-performance engines 

3.4.1 Standards and relationship to ABT 

What Commenters Said: 

NMMA commented that for CO, EPA is proposing a 350 g/kW-hr standard for highperformance engines. NMMA supports this level and agrees that the technological challenges 

faced by high performance engines require a CO standard at that level. Individual NMMA 

members will provide further comments and test data supporting the CO level proposed by EPA 

in the rule. With regard to HC+NOx, EPA requests comments on the need for and level of 

alternative emissions standards for high-performance SD/I engines. While EPA proposes two 

possible alternatives, NMMA members believe that the most appropriate approach for the highperformance engine segment is a modification of the second suggested alternative, which is a 15-

22 g/kW- hr standard for the high-performance segment, and to disallow credits. 72 Fed. Reg. at 

28,117. NMMA recommends instead that EPA adopt a non-catalyst based standard with a cap 

set at 20 g/kW-hr for engines with rated output of 373 kW-484 kW in 2010 with a further 

reduction to 16 g/kW-hr in model year 2011. NMMA will also support a cap of 25 g/kW-hr for 

engines with rated output of 485 kW and above in model year 2010 with a further reduction to 22 

g/kW-hr in model year 2018. These recommended levels are conditioned on the option of using 

the modified test cycle described below. Consistent with EPA’s second alternative, NMMA also 

recommends that no averaging, banking or trading of credits be allowed for either HC+NOx or 

CO. Most high-performance engine manufacturers do not have products below the 373 kW 

rating with which to average. In addition, these manufacturers cannot rely on credits being 

available on the open market from their competitors. By removing the option for averaging, 

banking and trading, EPA will ensure a level playing field among all manufacturers of highperformance engines. 

As EPA finalizes the standards for high-performance engines, NMMA encourages the 

Agency to work with CARB to ensure that the standards for high-performance engines are 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

harmonized to the greatest extent possible. CARB staff included in the “ARB Staff Report: 

Initial Statement of Reasons for Rulemaking, September 30, 2005” that it was the staff’s 

intention to return to the Board prior to the scheduled 2009 implementation date of the standards 

for “High Power Engines (greater than 373 kW)” and that they are awaiting the promulgation of 

the federal regulation. Thus, harmonization is clearly a priority for the CARB and NMMA urges 

EPA to work cooperatively with CARB to ensure consistency among the two regulatory 

schemes. 

Ilmor supports fixed standards for all high-performance engine manufacturers. Twotiered: 373-484 kW and >485 kW. Ilmor supports a rule with no ABT for high-performance 

sector. Ilmor supports harmonized standard for high-performance engines (>373 kw) for EPA 

and ARB. In a hearing, Ilmor commented that they estimate that 80% of the High-Performance 

engines are produced by 5 or possibly 6 manufacturers. (Mercury, llmor, Teague, Sterling, 

Flagship, Chief). An additional 10-20 very small businesses, produce as little as 15-25 engines 

per year each. 

NMMA members (North American Sleekcraft, Inc., Brunswick Corporation) commented 

that catalytic converters not practical for low niche market. They produce boats that use engines 

over 500hp. EPA should put a cap on the current emission limitations for high performance for 

level playing field for those who make such boats. They believe EPA realizes catalytic 

converters are not feasible on high performance engines. 

Brunswick makes boats that use engines over 500HP. They commented that the only 

logical choice for USEPA is to put a cap on the current emission limitations for highperformance engines in order to create a level playing field for those few manufacturers that 

make high performance engines. Brunswick believes USEPA realizes that catalytic converters 

are not feasible on high performance engines. 

Mercury Marine commented that EPA’s proposal recognizes the unique aspects of highperformance engines and will provide the necessary flexibility as long as several additional 

revisions are implemented. Mercury Marine is supportive of the flexibility provided for highperformance SD/I engines in the proposed rule. Mercury Racing produces High-Performance 

Engines as a stand alone division, and competes with several small businesses in this market. 

This is a uniquely American Industry, employing several thousand people between the engine 

manufacturers, boat builders and dealers. It is imperative that the same standards apply to all 

manufacturers. That said, several of these measures require additional revision in several 

respects to ensure that the standards both achieve the reductions that EPA intends as well as 

remain workable for the high-performance segment. 

For CO, EPA is proposing a 350 g/kW-hr standard for high-performance engines. 

Mercury Marine supports this level and agrees that the technological challenges faced by highperformance engines require a CO standard at that level. Mercury Marine has supplied 

confidential test data that supports this standard. 

EPA suggested that a possible way to reduce emissions from High Performance Engines 

was to add an air pump. Mercury Marine commented that first, the size of an air pump that 

3-31 
 

Chapter 3: Marine SI Engines 

would result in any meaningful reductions in emissions would be very large, and require 

considerable power to drive it. Further, no such pump currently exists. Mercury Racing tested 

air pumps some years ago, and was unable to get them to survive for more than 90 minutes of 

operation. 

With regard to HC+NOx, EPA requests comments on the need for and level of alternative 

emissions standards for high-performance SD/I engines. While EPA proposes two possible 

alternatives, Mercury Marine believes that the most appropriate approach for the highperformance engine segment is a modification of the second suggested alternative, which is a 15-

22 g/kW-hr standard for the high-performance segment and disallow credits. 72 Fed. Reg. at 

28,117. Mercury Marine recommends instead that EPA adopt a non-catalyst based standard with 

a cap set at 20 g/kW-hr for engines with rated output of 373 kW-484 kW in 2010 with a further 

reduction to 16 g/kW-hr in 2011. Mercury Marine will also support a cap of 25 g/kW-hr for 

engines with rated output of 485 kW and above in 2010 with a further reduction to 22 g/kW-hr in 

2018. These recommended levels are based on EPA offering the option of using the modified 

test cycle described below. 

Mercury commented that these standards will provide meaningful reductions in emissions 

from High Performance Engines. Mercury Racing has tested several existing engines. The 

current engines in the under 485 kW category have shown HC + NOx values in the range of 11 – 

18 g/kW-hr. They believe that there are engines, built by smaller companies, utilizing 

carburetors that are considerably higher on emissions. Every engine company has access to fuel 

injection technology, and they believe that a standard that forces the use of better, available, 

technology is appropriate. By 2011 they are recommending a cap of 16 g/kW-hr. 

For the category of over 485 kW, Mercury Racing currently has engines that have shown 

emissions totals of over 34 g/kW-hr. As with the lower category, they believe that there are 

carburetor equipped engines being produced by other manufacturers that are considerably higher 

than this. As previously stated, every engine company has access to fuel injection technology, 

and Mercury believes that a standard that forces the use of better, available, technology is 

appropriate. Mercury Racing has been able to calibrate their large engines down to 

approximately 21 g/kW-hr HC + NOx. Given those results, they endorse a standard set at 25 

g/kW-hr HC + NOx for this category in 2010, with a long term reduction to 22 g/kW-hr for 

2018. 

Sterling Performance is a small business engaged in the building of high performance 

marine engines and has been in this business for over 20 years. They are involved with racing 

and pleasure boat engines of the highest performance and durability. The high performance 

inboard marine sector consists of a very low volume of engines that we estimate the total U.S. 

annual sales of all builders combined to be less than 1500. These engines are generally used by 

other small businesses to power the watercraft they sell. Sterling Performance supports the 

proposal of the removal of the option for allowing the averaging, banking or trading of credits 

for either HC+NOx or CO. Since they do not produce engines below a rated output of 485 kW, 

they have nothing with which to average. Sterling asks that only a “level playing field” be 

considered for all manufacturers of high performance engines. They support a cap of 25 /kW-hr 

for engines with a rated output of 485 kW and above in model year 2010 with a further reduction 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

to 22 g/kW in model year 2018. In regards to certification testing, the E4 duty cycle overstates 

the idle fraction and an alternate duty cycle that allows for a nominal load factor of 15% in mode 

5 would be more appropriate. With the current ARB standard in place in California, Sterling 

Performance as a small business is essentially “out of business” in that state. It is of course their 

hope that the USEPA adopts a standard which will enable them to continue to build engines and 

further more that it may be harmonized with ARB so that once again the California market is 

open to them as a small business manufacturer of high performance engines. 

California ARB recommends that U.S. EPA remain committed to the 5 g/kW-hr 

HC+NOx standard and 2009 start-date for high performance sterndrive/inboard engines to align 

with existing California requirements, or to at least pursue an approach that yields equivalent 

emission benefits. ARB recognizes the challenges faced by small volume manufacturers of high 

performance engines to comply with the 5 g/kW-hr HC+NOx standard; however, they have 

equity concerns over giving a more lenient standard to the segment of industry with the product 

most able to absorb the costs of compliance. Still, ARB recognizes the benefits of national 

harmonization and is open to reasonable alternatives that would preserve the emission reductions 

of the existing spark-ignition marine regulations in California. ARB staff will carefully review 

the final U.S. EPA decision in this matter and proceed accordingly in determining whether or not 

a change is warranted for California’s high performance engine requirements. 

NY DEC commented that high performance engines available to the general public (i.e., 

not solely for competition) should be held to the same standards as all other sterndrive and 

inboard engines. 

Letters: 

Commenter Document # 

NMMA 0688 

NY DEC 0659 

Ilmor 0658 

Sterling 0665 

Mercury 0693 

CARB 0682 

North American Sleekcraft, Inc. 0666 

Brunswick Corporation 0695 

Our Response: 

We considered all the comments and are finalizing non-catalyst based standards for highperformance engines. The final rulemaking sets the HC+NOx emissions standards in 2010 at 20 

g/kWh for engines with output less than 485kW and 25 g/kWh for engines with output over 485 

kW. In 2011 and later model years, the HC+NOx emission standards drop to 16.0 g/kW-hr for 

engines at or below 485 kW and 22.0 g/kW-hr for bigger engines. The final standard maintains 

the proposed 350 g/kWh CO standard that is effective in 2010. Since the standards being 

adopted for SD/I high-performance engines are less stringent than originally proposed, we are 

not including the SD/I high-performance engines in the ABT program. Manufacturers are 

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Chapter 3: Marine SI Engines 

required to meet the emission standards for SD/I high-performance engines without using 

emission credits. 

We respect NY DEC’s desire to obtain greater emission reductions in the high 

performance engine segment; however, we have determined that the SD/I emission standards are 

not a feasible option for the high performance engines. Catalytic converters, which are required 

to meet the new SD/I emission standards, are not a viable technology in high performance 

engines. These engines produce very high exhaust flow rates and temperatures that make 

catalysts incapable of sustained and effective operation over extended engine operation. We are 

therefore implementing the most stringent standards achievable through calibration development 

and the expanded use of electronic fuel injection in high performance engines. 

ARB has recently relaxed its exhaust emission standards for SD/I high performance 

marine engines to be reflective of emission levels that can be attained without the use of 

catalysts. These emission standards are similar to those finalized today in this rule. To 

compensate for the associated shortfall in emission reductions, compared to the original 

standards, ARB is requiring that high-performance vessels use evaporative emission control 

systems including carbon canisters and low permeation tanks and hoses. Similarly, we are 

finalizing evaporative emission standards for all SI marine vessels subject to this rule. 

3.4.2 Lead time 

What Commenters Said: 

NMMA commented that the SD/I marine engine manufacturing industry will need lead 

time to comply with the emissions standards in the proposal. They continued to comment that 

this is especially true for the high-performance engine segment which will have to develop the 

technology to ensure compliance with the emissions standards without the use of averaging. The 

fact that engine manufacturers must comply with the high-performance California emission 

standards in 2009 does not assure compliance with a model year 2009 implementation date for 

national emission standards. As EPA states in the preamble, California represents only a small 

portion of the market and manufacturers will need to develop control technology for their entire 

product line. This cannot happen overnight and certainly manufacturers cannot begin the process 

of developing the control technology until the levels of the standards are finalized. Therefore, 

NMMA supports a model year 2010 implementation date for large businesses. 

With regard to small businesses that are in the high-performance segment, NMMA 

supports the additional compliance time proposed for these manufacturers. They believe that 

2011 is appropriate for high-performance small businesses and provides the requisite time for the 

control technology to be developed and tested. In addition, given that NMMA is recommending 

no averaging for this segment, the additional years for compliance will be critical for this 

segment. 

Mercury Marine also commented that the SD/I marine engine manufacturing industry 

will need lead time to comply with the emissions standards in the proposal. This is especially 

true for the high-performance engine segment which will have to develop the technology to 

ensure compliance with the emissions standards without the use of averaging. The fact that 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

engine manufacturers must comply with the California emission standards in 2009 does not 

assure compliance with a model year 2009 implementation date for the federal emission 

standards. As EPA states in the preamble, California represents only a small portion of the 

market and Mercury Racing may not offer all products in California in 2009. Therefore, the 

national rule implementation needs to be at least 2010 to provide sufficient time to develop lower 

emissions versions of these engines. 

With regard to small businesses that are in the high-performance segment, Mercury 

Marine will support additional time for compliance, but that additional time should be 2011. 

Allowing all of Mercury Racing’s competitors to not comply until 2013 is creating an unfair 

advantage to these companies which have access to the same technologies and capabilities as 

Mercury Racing. 

NMMA members (North American Sleekcraft, Inc., Lowe Boats, and Cigarette Racing) 

supported 2010-2011 implementation for catalysts to evaluate and design the lower emission 

engines into boats while ensuring performance and safety and soundness in economy. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury Marine 0693 

North American Sleekcraft, Inc 0666 

Brunswick Corporation 0695 

Baja Marine Corporation 0726 

Cigarette Racing 0637 

Lowe Boats 0660 

Our Response: 

 Given the timing of the final rule, we agree with NMMA’s suggestion to delay 

implementation until 2010 for large businesses. This will allow sufficient lead time to complete 

the design and certification effort associated with meeting the new emission standards. We 

however, will maintain the 2013 implementation date for small businesses. Small businesses do 

not currently have access to the testing equipment necessary to perform emission testing and 

subsequent emissions calibration. This additional lead time will allow them sufficient time to 

perform this testing and emissions calibration work. In addition, it will provide them sufficient 

time to upgrade their carbureted engines to electronic fuel injection. Given the high fuel rates of 

high performance engines, custom fuel injection systems will need to be developed for many of 

these engines. 

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Chapter 3: Marine SI Engines 

3.4.3 Special provisions for high-performance engines 

Summary of Comments Response 

NTE Testing: NMMA and Mercury Marine support the 

proposal to not to apply NTE requirements to the high 

performance engine segment. They state that many of 

the manufacturers in this segment are small businesses 

and the additional testing will cause significant testing 

burden and costs. 

We will finalize these provisions as proposed. 

Therefore, we will not apply NTE requirements to the 

high performance segment. 

Certification Testing: NMMA, Mercury Marine, and 

Ilmor support an alternative E4 test cycle for the high 

performance engine segment. They propose to increase 

the idle load at the Mode 5 point in the E4 test cycle 

from 0% to 15% load. The proposal is based on data 

from high performance boat builders and owners. The 

data reflected that high performance vessels spend 

significantly less time at idle (15%) than the E4 test 

weighting of 40%. In addition, the data showed that 

typically 8% of operating time is at idle with no load and 

18% of the time is at idle in gear, which is represented 

by the 15% load proposed at idle. 

We will adopt the optional alternate E4 test schedule for 

the high performance engine segment which allows 15% 

load at the Mode 5 idle point based on the data supplied 

by industry. We believe this is sufficient relief for the 

high performance engine segment based on the data 

provided by industry. 

Portable analyzers: NMMA suggested that portable 

analyzers do not provide any meaningful relief in testing 

burden. They stated that this equipment was not 

developed for the high-performance segment and that 

discrepancies between portable analyzers and a full test 

lab would create problems. 

In addition, NMMA expressed confusion that EPA 

would refer to portable analyzers for in-use testing of 

high performance engines given that in-use testing 

requirements were not proposed for SD/I engines. 

We have used currently available portable analyzers to 

perform valid and accurate measurement of emissions 

from high performance marine engines. It is true that 

portable analyzers will in some cases have somewhat 

greater variability than conventional laboratory 

equipment. Manufacturers may choose to take this 

greater variability into account as part of the decision 

whether or not to use portable analyzers for certification. 

If compliance margins are not big enough or where 

engine manufacturers otherwise do not want to deal with 

this greater availability, they may instead opt for the 

more expensive testing with conventional laboratory 

equipment. We note, however, that portable analyzers in 

some cases meet laboratory specifications, in which case 

no greater variability would be expected. 

The final preamble clarifies that EPA is adopting a 

provision that allows for SD/I high performance engine 

testing to be performed with different equipment than is 

specified for the laboratory with less restrictive 

specifications and tolerances. The less restrictive 

specifications are typical of the specifications required 

for in-use testing. 

Warranty and Useful Life: NMMA and Mercury Marine 

support the high performance warranty and useful life 

limits proposed in the NPRM. The proposal limits 

warranty and useful life to three years or 150 hours for 

engines with 373-484 kW output and one year or 50 

hours for engines with >485 kW output. They also state 

that the warranty and useful life limits proposed by EPA 

are consistent with CARB’s limits and it makes sense 

from a policy and technical perspective to harmonize the 

We will finalize the proposed high performance 

warranty and useful life provisions, which are 

harmonized with California ARB’s provisions. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

requirements. 

Broad Definition of Engine Families: Ilmor supports the We will finalize the proposed provisions for grouping all 

proposed broad definition of engine families in the high performance engines into a single engine family 

NPRM. This proposal allows high performance engine based on good engineering judgment. 

manufacturers to group all high performance engines 

into a single engine family based on good engineering 

judgment. 

Commenter Document # 

NMMA 0688 

Mercury Marine 0693 

Ilmor 0658 

3.5 Cross-category issues related to emission standards 

3.5.1 NTE limits (NTE Testing Burden and Need) 

What Commenters Said: 

Several commenters stated that they do not support the not-to-exceed (NTE) standards 

proposed in the regulation. Suzuki does not believe that NTE standards are necessary for the 

outboard engine product category in general. Honda suggested that EPA reconsider the NTE 

proposal of this marine engine regulation and not adopt NTE for marine engines. Honda also 

commented that the NTE section of this marine regulation should address the basic issue of 

defeat devices and not attempt to create a new undocumented test cycle with infinite test points. 

NMMA and Mercury suggested that the ABT program ensures that the emissions from a 

manufacturer’s fleet meet the standards, therefore NTE is not necessary. 

NMMA, Mercury, and Suzuki commented that the test burden associated with NTE 

standards is considerable. NMMA and Mercury also claim that the costs associated with the 

NTE tests are not adequately represented in the draft RIA. The commenters claimed that the 

practical effect of this requirement is that marine engine manufacturers will have to run hundreds 

more tests in the development process for engines. Such a resource intensive requirement is a 

considerable burden for this industry with little to no benefit to the environment. 

Yamaha commented that EPA originally explained that NTE was a component of 

certification only but now wants to utilize it as a form of Selective Enforcement Audit protocol 

causing undue and unsubstantiated burden on the engine maker. 

As an alternative to NTE, Honda suggests that EPA consider the acquisition of data from 

actual boat use (SD/I, outboard, and PWC with the full variety of engine technology that is 

available to power these vessels) that represents the nominal and off-nominal operating 

conditions. The data can be used to define a test procedure that is not infinitely burdensome and 

can be applied to all marine engine technologies. 

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Chapter 3: Marine SI Engines 

Honda does not support adoption of an NTE provision for marine engines. They were not 

in support of NTE provisions for ATVs in an earlier EPA rulemaking and the fundamental 

principles behind their opposition then apply here for this marine engine proposal. As an 

alternative, they would suggest that EPA consider the acquisition of data from actual boat use 

(SD/I, outboard, and PWC with the full variety of engine technology that is available to power 

these vessels) that represents the nominal and what is claimed to be off nominal operating 

conditions. From this data it may be determined that the extremes of operating conditions can be 

better defined. The data can also be used to define a test procedure that is not infinitely 

burdensome and can be applied to all marine engine technologies. On-the-water test procedures 

are also a section in the proposal where EPA is attempting to create a compliance limit when 

there is no test data, no test procedure, no hardware input and output parameters, and no basis to 

assume that there is some actual, reliably measurable, data that could be generated and compared 

with a dynamometer test. This is the basis for Honda’s suggestion that the NTE section of this 

marine regulation should address the basic issue of defeat devices and not attempt to create a 

new undocumented test cycle. 

Honda does not understand how the NTE sections apply specifically to outboards and 

PWCs. They assume that EPA may have intended that some of these sections apply only to SDI 

vessels. Outboards and PWC do not necessarily include any sensors or controls in a basic 4-

stroke carbureted engine so including them in this requirement, especially torque value 

broadcasting, would be a complete change in their configuration clearly not anticipated in either 

the regulatory implementation date nor in the cost analysis associated with the emission 

reductions. Without engine management, a simple air / fuel map of the engine in the operating 

range would be sufficient to demonstrate that the engine will provide proper emission 

performance and not introduce any form of “defeat device”. The basic purpose of NTE is to 

prevent the use of a defeat device that would impair emissions performance under normal 

operating condition or, under particular conditions, change the engine performance for some 

other benefit while adversely affecting emissions. EPA seems to have clearly stepped beyond 

this purpose and is in effect creating a new engine test cycle with infinite test points. Creating a 

new test cycle and setting standards for that cycle without real world data demonstrating that it is 

representative of boats in operation and is technically achievable by the boats / engines being 

regulated are clearly a violation of the basic technical principles upon which EPA has always 

developed test cycles. 

ARB commended U.S. EPA for its leadership role in developing and adopting NTE 

standards and test procedures for sterndrive/inboard engines. ARB believes the standards will 

allow sterndrive/inboard engine performance to be evaluated in-use under real-world operation. 

ARB staff recognizes the value to industry of harmonized requirements and will carefully review 

U.S. EPA’s NTE program when determining what NTE standards are appropriate for 

California’s own program. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Yamaha 0721 

Mercury 0693 

Suzuki 0698 

CARB 0682 

Honda 0705 

Our Response: 

We disagree with commenters’ position that NTE is unnecessary. NTE is a critical part 

of a comprehensive emissions program that is intended to ensure that emission controls function 

with relative consistency across the full range of expected operating conditions. Without NTE, 

we would not be able to ensure the emissions benefits expected from the regulation are realized 

in-use. 

Commenters stated that the ABT program ensures that emissions from a manufacturer’s 

fleet meet the standards and therefore NTE is not required. However, the commenter did not 

explain their perceived relationship between ABT and NTE. These are two very different 

programs. ABT refers to emission credit exchanges between different engines. NTE is a set of 

standard test procedures intended to ensure that emission control is achieved in–use. 

We disagree with Honda’s comment that NTE should solely address the use of defeat 

devices. No single test procedure or test cycle can cover all real-world applications, operations, 

or conditions. Yet to ensure that emission standards are providing the intended benefits in use, 

we must have a reasonable expectation that emissions under real-world conditions reflect those 

measured on the test procedure. The defeat device prohibition is designed to ensure that 

emission controls are employed during real-world operation and as a result emission reductions 

are achieved in the real world, not just under laboratory testing conditions. However, the defeat 

device prohibition is not a quantified standard and does not have an associated test procedure, so 

it does not have the clear objectivity and ready enforceability of a numerical standard and test 

procedure. We believe using the traditional approach, i.e., using only a standardized laboratory 

test procedure and test cycle, makes it difficult to ensure that engines will operate with the same 

level of control in use as in the laboratory and therefore makes it difficult to enforce a defeat 

device prohibition. Thus, we believe there are significant advantages to establishing NTE 

standards. In addition, the final NTE test procedure is flexible, so it can represent the majority of 

in-use engine operation and ambient conditions. The NTE approach thus takes all the benefits of 

a numerical standard and test procedure and expands it to cover a broad range of conditions. 

With the NTE approach, in-use testing and compliance become much easier because emissions 

may be sampled during normal boating. In sum, by establishing an objective measurement, our 

NTE approach makes enforcement of defeat device provisions easier, provides more certainty to 

EPA and the industry, and is crafted to be flexible and represent most in-use engine operation 

and ambient conditions. 

3-39 
Chapter 3: Marine SI Engines 

We disagree with industry’s comments that the test burden associated with NTE is 

considerable with either current or future engines. Data supplied by manufacturers show that 

emissions from existing low emission engines in many areas of the NTE zone are generally 

below the limit today. We believe the technology used to meet the standards over the five-mode 

duty cycle will meet the caps that apply across the NTE zone. We therefore do not expect the 

final NTE standards to cause manufacturers to need additional technology. We believe the NTE 

standard will not result in a large amount of additional testing, because these engines should be 

designed to perform as well in use as they do over the five-mode test. However, our cost 

analysis in the Final RIA accounts for some additional testing, especially in the early years, to 

provide manufacturers with assurance that their engines will meet the NTE requirements and 

therefore meet applicable standards in-use. 

The test burden also will not be as great as industry assumed from the proposal because 

of the lead time and carry-over provisions permitted in the final regulation. Manufacturers have 

at least two years to develop efficient NTE test methods that focus on areas of high emissions 

before NTE is required. We also added a small business provision that allows an additional year 

of lead time. We exempted the high performance engine segment from NTE testing altogether 

because we have very limited information on their detailed emission characteristics and we are 

concerned about extent of testing that would be required by the large number of affected engine 

manufacturers that are small businesses. We also considered testing burden by allowing 

manufacturers to carry-over certification on engines certified prior to 2010 until 2012 for OB 

engines and 2013 for PWC and SD/I. Like emissions certification, the manufacturers will be 

able to carry-over NTE certification until the engine design changes significantly. 

We also disagree that the NTE testing burden is not accounted for properly in the RIA. 

In the RIA Chapter 6.3.5, we recognized that manufacturers may need to adjust engine 

calibrations to meet the proposed standard and collect further data to demonstrate compliance 

with the proposed not-to-exceed zone. We therefore allow on average two months of R&D for 

each engine family as part of the certification process. Considering two engineers and three 

technicians and the corresponding testing costs for the two-month period, we estimate a total cost 

of $130,000 per engine family. Unless engine designs were significantly changed, 

manufacturers could recertify engine families each year using carryover of this original test data. 

Commenters did not provide detailed information on their cost estimates for NTE testing. 

Honda commented that actual in-use boat data should be used to create the NTE zone. 

We developed this zone based on the range of conditions that these engines typically see in use. 

Manufacturers collected data on several engines installed on vessels and operated under light and 

heavy load. Chapter 4 of the Final RIA presents this data and describes the development of the 

boundaries and conditions associated with the NTE zone. Although significant in-use engine 

operation occurs at low speeds, we are excluding operation below 40 percent of maximum test 

speed because brake-specific emissions increase dramatically as power approaches zero. An 

NTE limit for low-speed or low-power operation will be very hard for manufacturers and EPA to 

implement in a meaningful way. 

We value CARB’s support for our NTE testing and we agree with them on the value of 

harmonized requirements for NTE test protocol and standards. 

3-40
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

3.5.2 Lead time for NTE standards 

NMMA and Mercury Marine commented that there are certain NTE implementation 

issues that EPA’s proposal fails to consider and accommodate in the proposed requirements for 

Marine SI engine manufacturers in § 1045.205. Specifically, the requirement in § 1045.205(p) 

that the application for certification contain a statement that all the engines in the engine family 

comply with the NTE limits and the requirement to include any relevant testing, engineering 

analysis, or other information to support the statement is particularly troublesome. 72 Fed. Reg. 

at 28,270. While this requirement may not be a problem for new engine families, for engine 

families that are carried over, EPA must delay the NTE requirements in the certification 

application. Otherwise, manufacturers would have the impossible task of having to retest all of 

their engine families, including those that existed prior to the applicability of the NTE standards. 

To address the carryover situation, NMMA and Mercury recommend that EPA include in § 

1045.205(p) language that would specify that test data for carryover engines compliant with the 

standards can be carried over through model year 2014 and that certification is valid until the 

engines must be recertified for other reasons. Section 1045.205(p) should be revised to state: 

(p) For new engine families, state that all the engines in the engine family comply 

with the not-to-exceed emission standards we specify in subpart B of this part for all 

normal operation and use when tested as specified in § 1045.515. Describe any relevant 

testing, engineering analysis, or other information in sufficient detail to support your 

statement. Through model year 2014, any prior model year engine certified under the 

Tier I standards in Part 91 may carry over test data and is not subject to NTE as long as 

the engine meets the applicable standards in this subpart. 

This additional language will ensure that manufacturers will be able to transition to the 

new standards without having to retest all of their prior engine families that are already 

compliant with the standards. 

Mercury commented that they have a suggestion on the NTE Zone Implementation that 

may make it easier to come to an agreement and implement. Whatever approach is put in the 

rule, for 2010, 2011, 2012 manufacturers would test to it and report the results with new 

certifications. They would make a good faith effort to comply with it, but there would be no 

penalty for noncompliance. Then, in 2012, EPA and industry would do a tech. review and see 

what worked and what didn't, modify it as needed, and future new certifications would need to 

meet it. This is similar to the concept that CARB is using on catalyst monitoring, where for the 

first two years, industry has to do catalyst monitoring and store fault codes, but they do not have 

to activate the warning horn/MIL light. 

Provided EPA adopts the current 3-Star California exhaust emission standard for PWC 

and Outboards, BRP can fully comply with this standard in MY2009 if EPA allows carry-over 

data to be used. It is not possible for BRP to re-test their PWC or Outboard engines for 

compliance with the proposed Not To Exceed (NTE) Zone requirements or proposed change to 

the maximum test speed in time for MY2009 certification. As a result, BRP is supportive of the 

NMMA comment to exempt carry-over engine families from the NTE and maximum test speed 

3-41 
Chapter 3: Marine SI Engines 

provisions in this regulation through MY2013. Please refer to the carry-over certification 

discussion below. 

BRP supports NMMA proposal to have carry-over engine families from the existing 

marine regulation and early-certified engine families meeting the exhaust emission standards of 

the proposed regulation be exempt from the proposed NTE test requirements and maximum test 

speed definition change through MY2013. It is necessary for BRP to phase in engine families to 

the new testing requirements over the next few model years. It is infeasible to re-test every 

engine family within the next couple years to verify compliance with the NTE proposal. In 

addition, allowing carry-over data to be exempt from the NTE and maximum test speed 

provisions will create an incentive for BRP and other manufacturers to certify their engine 

families to the new emissions standards in an earlier model year. 

Yamaha supports NMMA comments that all HC+NOx compliant engine families under 

Tier 1 not be subject to NTE testing until that family undergoes a major change or resubmitted as 

new model until M/Y 2014. This will help offset the time and costs associated with an NTE test. 

Letters: 

Commenter Document # 

Bombardier 0674 

Yamaha 0721 

Mercury 0693 

NMMA 0688 

Mercury 0693 

Mercury 0716 

Our Response: 

Manufacturers commented that certification to the NTE standards requires additional 

testing for engine models that are already certified to the new emission standards for California. 

In addition, they expressed concern that they may need to recalibrate existing engine models to 

meet the NTE standards. Manufacturers commented that this would not be possible by the date 

of the duty cycle standard. For engines already certified in California, manufacturers carry over 

preexisting certification test data from year to year. Manufacturers commented that additional 

time would be necessary to retest, and potentially recalibrate, these engines for certification to 

the NTE standards. To address these issues regarding lead time needed to retest these engines, 

we are not applying the NTE standards for 2010-2012 model year engines that are certified using 

preexisting data (i.e., carryover engine families). For new engine models, manufacturers 

indicated that they will be able to perform the NTE testing and duty-cycle testing as part of their 

efforts to certify to the new standards. Therefore the primary implementation date of 2010 

applies to these engines. Beginning in the 2013 model year, all OB/PWC and conventional SD/I 

engines must be certified to meet the NTE standards. 

We believe that the NTE requirements are technologically feasible in the time frame 

adopted in this rule. These NTE limits are supported by data in the RIA and have been further 

3-42
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

confirmed by confidential data submitted by individual manufacturers. Therefore, we do not 

believe that a tech review is warranted. 

3.5.3 NTE zones, subzones, and test specifications 

What Commenters Said: 

NMMA, Mercury, and Bombadier commented that EPA’s proposed NTE requirements 

do not reflect how marine engines are certified and designed and do not accommodate the 

majority of engine designs. They stated that exhaust emissions vary by engine technology across 

the 5- mode weighted average test cycle used to determine Marine SI emission certification 

levels. In addition, the commenters stated that the emission levels at each of the five test points 

can vary significantly from the declared FEL. The commenters believe that EPA's NTE proposal 

forces an area around each point of the certification duty cycle to meet the engine family's FEL 

times a multiplier regardless of the certification data for that point. Suzuki commented that their 

full line of outboard engines comply with the stringent CARB 2008 HC+NOx levels but EPA's 

proposed NTE test requirements and emissions standards under any of the available NTE 

subzone sets will be too severe for several existing engine families to attain without costly and 

time consuming redesign. 

NMMA, Pleasurecraft Marine, Indmar, Mercury Marine, Bombardier, Volvo Penta, and 

Suzuki support using the second alternative discussed in the NPRM preamble, which is a 

weighted average approach to the NTE limit rather than an individual NTE limit for each 

subzone. Under this approach, an emission measurement would be made anywhere within each 

of the subzones plus idle. The measured emissions would then be combined using the weighting 

factors for the E4 modal test. The commenters believe that the proposed alternative NTE Zone 

will ensure a common test methodology to test all different types of marine engines. 

NMMA has provided EPA with a full description of a NTE zone shape that they believe 

makes sense for all engine categories and addresses the open loop phase of catalyst operation 

during the marine duty cycle. The proposed shape of the subzones was supported by industry. 

NMMA’s proposed a dividing line for Subzone 1 at 85% engine speed and 80% engine torque to 

accommodate all Marine SI technologies, including open-loop fueling for catalyst protection in 

the SD/I engines. They proposed that Subzones 2 and 3 are defined by the ICOMIA 5-mode 

cycle, but the wide open throttle point was defined by the 85% speed and 80% torque boundary 

of Subzone 1. NMMA proposed the lower boundary for Subzone 2 at 68% of rated test speed 

and Subzone 3 at 51% of rated test speed. Subzone 4 is defined as the remaining areas of the 

NTE zone. 

 Bombardier commented that EPA's NTE proposal forces an area around each point of the 

certification duty cycle to meet the engine family's FEL times a multiplier regardless of the 

certification data for that point. They also stated that despite the three sets of multipliers 

available, this is not a proposal BRP can comply with without substantial lead time. BRP desired 

to meet with EPA and other industry members to reach a consensus on the NTE requirements. 

3-43 
Chapter 3: Marine SI Engines 

Mercury stated that the key to ensuring that the NTE limits will be workable for all 

engine categories is to have a multiplier that will allow for the “worst case” engines. Otherwise, 

they believe EPA would need to develop subgroups to accommodate every engine category. 

Mercury Marine believes that a multiplier of 2.0 with the weighted zone approach is required to 

make this concept work. 

Assuming the proposed weighted-average test method is adopted, Suzuki believes an 

appropriate NTE multiplier for 4-stroke outboard motors is 1.6 times the certification FEL for 

HC+NOx and CO emissions. Suzuki believes this proposed multiplier will accomplish EPA's 

stated objectives for NTE, and will not penalize small 4-stroke outboard engines that that are not 

equipped with fuel injection. 

Yamaha’s PLT testing indicates that the multipliers outlined in the proposal are too 

stringent when applying to PLT tests of various engine technologies and fuel delivery methods 

with little or no break-in time beyond what is allowed for current PLT preparation. Yamaha 

recommends NTE multipliers of 1.5 times the FEL (un-weighted). 

Manufacturers have commented that do not have enough information to fully evaluate the 

feasibility of the NTE zone for future SD/I engines. Manufacturers have expressed concern that 

the new line of supercharged GM will result in engines with higher exhaust temperatures than 

current designs. The commenters suggest that higher exhaust temperatures may require open 

loop fuel operation at lower speeds and loads, including some operation in subzone 2. 

Several manufacturers submitted data for our analysis and development of multipliers. 

The data can be found in the RIA Chapter 4. 

Letters: 

Commenter Document # 

NMMA 0688 

Indmar 0667 

Bombardier 0674 

Mercury 0693 

Suzuki 0698 

Pleasurecraft Marine (hearing) 0642 

Our Response: 

We have re-worked the NTE test protocol with industry to develop a new approach. The 

proposal discussed several approaches to the NTE testing protocol. We requested comment from 

industry on several alternatives. Industry commenters provided input to the advantages and 

shortcomings of these approaches. Manufacturers specifically stated that there are many 

different engine technologies and suggested high multipliers that could be met by existing 

engines. We continued to work with the manufacturers since they submitted their written 

comments to address these important issues. 

3-44
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

The OB/PWC NTE multipliers are slightly revised from the proposed procedure to better 

reflect the emissions performance of four stroke engines. We are raising the HC+NOx limit in 

Subzones 1, 2, and 3 from 1.2 to 1.4. In the event where OB/PWC engines are fitted with 

catalysts, manufacturers would use the NTE requirements for catalyzed engines that were 

originally designed for SD/I engines (with catalysts). This is appropriate because the emissions 

characteristics for engines equipped catalysts, in the NTE zone, are driven primarily by the 

catalyst efficiency rather than the engine calibration. This is especially true at high speed/power 

operation when the engine may need to run rich as a catalyst protection strategy. During this rich 

operation, the catalyst would not effectively reduce HC or CO. Detailed data is included in the 

RIA Chapter 4. 

The two-stroke OB/PWC engines have apparent high engine operation variability, as 

stated in the proposal. Therefore, we singled out the two-stroke engines based on industry 

recommendation. We are adopting a single weighted limit of 1.5 times FEL for the entire zone. 

Four-stroke SD/I engines are unique from the OB/PWC engines because they are 

expected to use a catalyst to meet the new standards. We are adopting changes to the subzone 

shapes for SD/I in the final rule based on industry comments. First, we are modifying the shape 

of the NTE zone to reflect the emissions performance differences between open loop and closed 

loop fuel operations. We are combining subzones 2, 3, and 4 into a single subzone to reflect the 

common closed loop engine operation in these areas. Second, we are increasing the subzone 1 

area to address the points that require open loop fuel operation to maintain safe exhaust 

temperatures based on data from industry. We believe that the finalized subzone 1 area is 

properly defined for catalyst-equipped engines based on current engine blocks. In addition, 

initial data from General Motors indicates that the finalized subzone 1 may also be appropriate 

for 6.0L supercharged engines. However, this is not certain. As engine manufacturers begin 

their development of the new catalyst-equipped, supercharged, SD/I engines, more information 

will become available on the exhaust temperature characteristics of these engines. If it becomes 

apparent that these engines cannot be designed to meet the NTE requirements, then we would 

consider revisiting the NTE subzones and limits to address this issue. 

3.5.4 Altitude 

What Commenters Said: 

ARB strongly encourages U.S. EPA to withdraw its proposal for exempting all 

recreational marine engines from compliance with emission standards at altitudes greater than 

2000 feet above sea level (< 94 kPa) as described in Section IV.D.(4) of the preamble. Although 

the preamble justifies this limitation because of a presumed majority of boating activity at sea 

level or low altitude, many lakes in California popular to boaters reside significantly above 2000 

feet. Examples include Lake Tahoe at 6225 feet above sea level, Lake June at 7612 feet above 

sea level, and Big Bear Lake at 6743 feet above sea level. Furthermore, the proposed altitude 

limitation would effectively exempt recreational marine engines from having to comply with 

emission standards in-use for all of New Mexico, Wyoming, Utah, and Colorado, which reside 

entirely at or above 2000 feet above sea level. Additionally, fourteen U.S. states in total have a 

mean elevation at or above 2000 feet above sea level. While ARB understands that requiring 

3-45 
Chapter 3: Marine SI Engines 

manufacturers to perform certification testing at high altitudes may be inconvenient, they 

maintain that manufacturers must remain liable for complying with emission standards in-use, as 

feasible, at all elevations where significant boating activity occurs. As a compromise, ARB 

recommends allowing manufacturers to certify engines using test data generated at or around 

2000 feet above sea level, but to provide an engineering evaluation stating that the engine will 

still comply with the applicable emission standards up to 8000 feet above sea level. Requests for 

exemptions from the 8000 feet above sea level threshold could be considered on a case-by-case 

basis. 

Letters: 

Commenter Document # 

CARB 0682 

Our Response: 

We acknowledge that there are lakes at elevations greater than 2000 feet above sea level. 

While this boating activity is less prominent than that occurring at lower altitudes, we agree that 

the regulations should not automatically exempt marine engines based on operation above 2000 

feet of altitude. For electronically controlled engines with feedback controls, designing engines 

that can compensate for altitude effects is straightforward. The bigger challenge is for open-loop 

engines where there is much less opportunity to incorporate design parameters that would 

compensate for altitude effects. 

In discussions with engine manufacturers after the proposal, there was general agreement 

that the approach we proposed for nonhandheld Small SI engines would be appropriate to extend 

to Marine SI engines. We are therefore adopting those same requirements for Marine SI engines 

in the final rule. In summary, this would include the following provisions: 

• Engines must comply with emission standards in the standard configuration at all 

atmospheric pressures above 94 kPa, which generally corresponds to an altitude of 2000 

feet above sea level. 

• Engines must comply with emission standards at atmospheric pressures above 80 kPa, 

which generally corresponds to an altitude of about 6400 feet above sea level. This may 

involve an altitude kit, which would be described in the application for certification with 

supporting information (engineering analysis and/or test data). This atmospheric pressure 

is the lowest value for performing a valid test under 40 CFR part 1065. 

• Manufacturers must describe their plan for making information and parts available to 

reasonably expect that altitude kits would be widely used in high-altitude areas if the 

engine depends on such a kit for complying at high altitudes. 

See the discussion of altitude-related comments for Small SI engines in Section 2.2.7 for 

additional information. 

3.5.5 Methane measurement 

What Commenters Said: 

3-46
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

CARB commented that although not in alignment with California’s existing regulations 

for outboard/personal watercraft and sterndrive/inboard engines, the use of a total hydrocarbon 

(THC) criterion for determining compliance with the HC+NOx standards is not opposed by ARB 

since a numerically equivalent THC standard would be more stringent than basing compliance 

on only the reactive component of hydrocarbon emissions. California’s existing recreational 

marine standards are based solely on non-methane hydrocarbon because methane is not an ozone 

precursor. However, methane is a greenhouse gas with climate changing potential; therefore, 

inclusion in the HC+NOx standard could be beneficial if methane emissions are always 

decreased in proportion to non-methane components regardless of the emissions control 

technology employed. As an alternative to the present proposal, U.S. EPA might consider the 

adoption of a separate standard for methane to ensure more meaningful emission reduction 

levels. 

Letters: 

Commenter Document # 

CARB 0682 

Our Response: 

Whether one considers ease of measurement, climate change, or matching the form of the 

standard with the available emission control technologies, the conclusion is that a total 

hydrocarbon standard is a sound basis for setting emission standards for Marine SI engines. We 

agree with the observation that methane emissions will decrease as a result of setting a THC 

standard. We are adopting emission standards in the form of total hydrocarbons, as proposed. 

3.6 Averaging, banking, and trading 

What Commenters Said: 

NMMA and Mercury Marine supported the inclusion of an Averaging, Banking and 

Trading Program for OB/PWC engines and also for SD/I engines. 

CARB encouraged EPA to rescind provisions for emission credit banking and trading for 

all recreational marine engines or to at least depreciate the value of banked credits over time. 

They expressed concern that it may be possible for manufacturers to certify their engines to 

emission levels that are considerably lower than required, even within proposed family emission 

limit (FEL) caps, which could delay the introduction of more stringent emission standards in the 

future for some manufacturers (if enough credits have been banked). CARB noted that the EPA 

makes a similar argument for disallowing the banking of CO credits from outboard/personal 

watercraft engines, and stated that the argument is applicable to the other regulated pollutants as 

well as sterndrive/inboard engines. 

3-47 
Chapter 3: Marine SI Engines 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

CARB 0682 

Our Response: 

EPA is retaining the ABT programs for Marine SI engines in the final rule. There will be 

one ABT program for OB/PWC engines and a separate ABT program for SD/I engines at or 

below 373 kW. The ABT program for OB/PWC engines will include averaging, banking and 

trading provisions for the HC+NOx standard and averaging provisions only for the CO standard. 

The ABT program for SD/I engines at or below 373 kW will include averaging, banking and 

trading provisions for both the HC+NOx standard and the CO standard. (As described in Section 

3.4.1, EPA is finalizing a set of emission standards for high performance SD/I engines that do 

not include ABT provisions.) EPA believes ABT programs are an important element in setting 

emission standards that are appropriate under Clean Air Act section 213(a) with regard to 

technological feasibility, lead time, and cost, given the variety of engines covered by the Marine 

SI standards. Depending on their design, ABT programs can create an incentive for the early 

introduction of new technology, allowing certain engine families to act as trailblazers for new 

technology. This can help provide valuable information to manufacturers on the technology 

before they apply the technology throughout their product line. 

EPA believes the banking and trading provisions are important parts of the ABT program 

for the HC+NOx and CO standards for SD/I engines at or below 373 kW and the HC+NOx 

standard for OB/PWC engines and we are retaining them for final rule. (As noted in the 

proposal, EPA does not believe banking and trading provisions are appropriate for the CO 

standards being applied to OB/PWC engines given the level of the CO standard.) Banking 

provisions, including early banking provisions (discussed below in Section 3.6.4), create an 

incentive for manufacturers to go beyond the requirements set by EPA and also create an 

incentive for early introduction of new technology. EPA believes this behavior should be 

encouraged because early introduction can also secure earlier emission benefits. With regard to 

trading, EPA believes that trading can help manufacturers that, for whatever reason, are 

struggling with meeting the standards. Trading has happened very infrequently under EPA’s 

ABT programs, most likely due to cost and competitiveness issues. However, it could prove 

very useful to a company that is having short-term difficulty with complying with the standards, 

where other means of addressing the problem do not exist. 

3.6.1 Credit life 

What Commenters Said: 

NMMA and Mercury Marine both supported the proposal to use an unlimited credit life 

for credits used in the ABT Programs for both OB/PWC engines and SD/I engines. In the event 

that EPA determines it is necessary to limit the credit life, NMMA and Mercury Marine 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

commented that EPA should apply the alternative approach suggested in the preamble, which 

would be to limit the credit life to the regulatory useful life of the engine. This would mean that 

the credits generated by a particular engine would be available while that particular engine is in 

the fleet. This would avoid concerns voiced by EPA in the preamble about credits being used 

years after the engine that generated the credits is no longer in the fleet. Moreover, NMMA and 

Mercury Marine noted that the ability to continue to carry over credits generated in the existing 

ABT program for OB/PWC engines into the new ABT program rewards manufacturers that have 

produced engines cleaner than the standards. 

CARB commented that it would support the limitation of credits based on the useful life 

of the engine as proposed. Further, CARB recommended that previously banked credits not be 

applicable for use on models after a change in standards has occurred. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

CARB 0682 

Our Response: 

We are retaining the unlimited lifetime for ABT credits under the Marine SI ABT 

program, as proposed. While EPA is retaining the unlimited lifetime, EPA notes that 

manufacturers should not assume that these credits will be available without any restrictions on 

their use if, and when, EPA should consider a new round of emission standards in the future. In 

revising emission standards, section 213(a)(3) of the CAA requires EPA to set standards which 

achieve the greatest degree of emission reduction that is technologically achievable, taking into 

consideration such items such as cost, safety and lead time. If manufacturers have a large pool 

of ABT credits available to them, EPA must consider ways to ensure that those credits do not 

result in an unnecessary delay of the standards. This can be done in a variety of ways, and has 

been done in other ABT programs by allowing only limited numbers of existing credits to be 

used for a limited period of time during the transition to the new standards. 

EPA does not believe a limit on the life of the credits is needed for the Marine SI ABT 

program adopted with today’s program. Credits are generated at a cost to manufacturers and 

thus they have a value to the manufacturers. Provisions which limit a manufacturer’s ability to 

use credits, such as a limit on credit life, will reduce the incentive for manufacturers to invest in 

the development and introduction of new technology. As mentioned above, manufacturers 

should not assume that an unlimited life means the credits will be available without any 

restrictions on their use if, and when, EPA should consider a new round of emission standards in 

the future. EPA would expect to consider ways to ensure that existing credits would not result in 

an unnecessary delay of any future standards. 

3.6.2 Averaging sets and other restrictions 

What Commenters Said: 

3-49 
Chapter 3: Marine SI Engines 

NMMA commented that the ability of engine manufacturers to use credits 

interchangeably between OB and PWC engines is important in ensuring compliance with the 

standards. 

NMMA and Mercury Marine commented that it is critical that jet boats be allowed to 

average credits, both HC+NOx and CO, with OB/PWC engines to provide flexibility and to 

ensure that jet boats will be able to meet the SD/I emission standards. NMMA noted its support 

of the proposed approach discussed in the preamble and in the proposed regulatory text in 

§1045.701(d), provided CO averaging was included. 

 Bombardier commented that it supported the proposed corporate averaging provisions in 

§1045.701(d) which allows SD/I engines certified under §1045.660 for jet boats to use HC+NOx 

exhaust credits generated from OB/PWC engines, as long as the credit-using engine is the same 

model as an engine model from an OB/PWC family. However, for the corporate averaging 

provision of §1045.701(d) to be meaningful to a manufacturer, Bombardier commented that CO 

averaging is also essential for achieving compliance. In addition, Bombardier premised their 

comments on the feasibility of having their jet boat models comply with the SD/I standards 

beginning with MY2011 (see Section 3.2.3, above) on the basis that §1045.701(d) is expanded 

to allow CO averaging. 

NMMA and Mercury Marine recommended that EPA remove the restriction regarding 

the ability of an engine to earn credits for one pollutant when using credits to comply with the 

emissions standard for another pollutant for both OB/PWC engines and SD/I engines. They 

commented that this restriction does not serve any useful purpose. From an emission reduction 

perspective, EPA will still see the pollution reduction across a manufacturer’s fleet even with the 

restriction lifted. NMMA and Mercury marine noted that EPA’s rationale for this restriction is 

that it has been imposed in other programs and is therefore justified for the marine engine 

category. They do not believe this is a sound basis for such a restriction. NMMA commented 

that U.S. Coast Guard (USCG) data demonstrates that an averaging approach to controlling 

emissions results in emission reductions. Thus, NMMA believes a restriction is unnecessary 

from an environmental perspective. 

From a technical perspective, NMMA and Mercury Marine commented that this 

proposed restriction unduly penalizes certain engines in manufacturers’ fleets. For example, for 

OB/PWC engines, some direct injection two-stroke engines have very low CO emissions but 

have higher HC+NOx emissions. Mercury Marine noted that many DI 2-Stroke Engines are 

borderline on meeting the standard for HC+NOx, but have extremely low CO emissions, usually 

under 100 g/kW-hr.) Thus, these engines would have to use HC+NOx credits for compliance but 

would be ineligible to generate CO credits. NMAA commented that the inability to earn CO 

credits for these engines will have a significant impact on certain manufacturer’s product plans 

developed to assure compliance with the standards. 

With regard to the proposed restriction for SD/I engines, Mercury Marine commented 

that GM will be launching a new base engine in 2010 (6.0 L S/C) that may be negatively 

impacted by this approach. The supercharged engine may need to run rich of stoichiometric at 

3-50
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Mode 2 and may be high on CO emissions at that point. Mercury Marine note they are forced to 

use GM base engines as they are the only ones that fit within the tight packaging requirements of 

the boat builders. 

As noted earlier at the beginning of Section 3.6, CARB commented that EPA should 

rescind the provisions for credit banking and trading. Should EPA decide to keep the banking 

and trading provisions for marine engines, CARB encouraged EPA to depreciate the value of 

banked credits over time. CARB is concerned that it may be possible for manufacturers to 

certify engines to emission levels that are considerably lower than required, even within 

proposed family emission limit (FEL) caps, which could delay the introduction of more stringent 

emission standards in the future for some manufacturers (if enough credits have been banked). 

They noted that EPA made a similar argument for disallowing the banking of CO credits from 

OB/PWC engines, and CARB believes the argument is applicable to the other regulated 

pollutants as well as SD/I engines. 

CARB also recommended that cross class trading not be allowed. Finally, CARB 

recommended that deficits not be carried over to future years without significant penalties. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

CARB 0682 

Bombardier (hearing) 0642 

Bombardier 0674 

Our Response: 

 With regard to the averaging sets for the Marine SI ABT program, EPA is adopting two 

averaging sets. OB/PWC engines will be in one averaging set. SD/I engines at or below 373 kW 

will be in another averaging set. (As discussed in Section 3.4.1, the final regulations for highperformance SD/I engines do not include ABT.) There will be no mixing of credits between the 

two sets of engines, except under certain conditions for jet boat engines. Jet boat engines are 

subject to the SD/I engine standards. Manufacturers will be able to use credits generated from 

OB/PWC engines to demonstrate that their jet boat engines meet the HC+NOx and CO standards 

for SD/I engines. Engine manufacturers can only use this provision if the majority of units sold 

in the United States from those related engine families are sold for use as OB/PWC engines. 

Finally, the manufacturer must certify these jet boat engines to an FEL at or below the applicable 

emission standards for a similarly-powered OB/PWC engine. While the preamble to the 

proposal noted manufacturers could use this special provision for jet boat engines for 

demonstrating compliance with both the HC+NOx standard and the CO standard, the proposed 

regulations failed to include a reference for CO. The reference to the CO standard has been 

included in the regulations for the final rule. 

With regard to restriction regarding the ability of an engine to earn credits for one 

pollutant when using credits to comply with the emissions standard for another pollutant, EPA is 

3-51 
Chapter 3: Marine SI Engines 

dropping that provision for the final rule. While EPA proposed such a restriction, it was 

modeled on similar requirements in other ABT programs where there was concern that a 

manufacturer could use technologies to reduce one pollutant while increasing another pollutant. 

In such cases, EPA did not want to allow manufacturers to both generate credits for one pollutant 

while using credits for another pollutant. In order to comply with the standards applicable to 

OB/PWC engines and SD/I engines at or below 373 kW, the types of technologies manufacturers 

are expected to use technologies such as direct-injection 2-stroke engines or 4-stroke engines for 

OB/PWC engines and catalysts along with engine improvements for SD/I engines. All of these 

technologies should result in reductions in both HC+NOx emissions and CO emissions 

compared to current designs. While the technologies are expected to reduce both HC+NOx 

emissions and CO emissions, there could be situations where these technologies are capable of 

meeting one of the emission standards but not the other. EPA does not want to preclude such 

engines from being able to certify using the provisions of the ABT program and is therefore 

dropping the proposed restriction from the final rule. 

With regard to comments on discounting of emission credits, we are not adopting such 

provisions for the ABT program. Discounting emission credits is similar to limiting the lifetime 

of credits. Both provisions lower the value of a credit to a manufacturer. As noted earlier in the 

discussion on credit lifetime, EPA believes that emission credits are generated at a cost to 

manufacturers and thus they have a value to the manufacturers. Provisions which limit a 

manufacturer’s ability to use credits, such as a “significant” discount, will reduce the incentive 

for manufacturers to invest in the development and introduction of new technology, which is a 

key goal of an ABT program. 

In response to the comments on credits deficits, it can be noted that EPA did not propose 

to allow credits deficits under the Marine SI ABT program. EPA is not including any deficit 

provision in the final regulations for the Marine SI ABT program. 

3.6.3 FEL caps 

What Commenters Said: 

Mercury Marine commented that the FEL cap for jet boat engines should be the same as 

the FEL cap for OB/PWC engines because jet boat engines are derived from these products. 

 Bombardier noted that it is supportive of the effort to develop alternative fuels to reduce 

petroleum-based fuels consumption. Bombardier commented that EPA has proposed maximum 

FEL caps for marine engines which may impede a manufacturer's effort to provide alternative 

fueled marine engines. Bombardier requested that engines using fuels other than gasoline, 

alcohol and natural gas be exempt from the HC+NOx maximum FEL proposed in 40 CFR 

1045.103 (b)(1). Because these engine families would still be subject to the proposed corporate 

averaging requirements, any increase in HC+NOx emissions would be off-set by further 

HC+NOx reductions of other engine families. Bombardier reasoned that this change would be 

an emission neutral (or beneficial) change to the regulation, and would help support a 

manufacturer's efforts to develop alternatively fueled marine engines. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

Mercury 0693 

Bombardier 0674 

Our Response: 

As proposed, we are classifying jet boat engines as part of the SD/I engine category, 

subject to the SD/I standards. However, because many jet boats, today, use OB/PWC engines, 

we are providing additional regulatory flexibility in which limited jet boat engines may be 

certified using OB/PWC emission credits. To be eligible for this flexibility, the jet boat engines 

must meet the OB/PWC standards. We believe that this FEL cap is necessary to limit the degree 

to which manufacturers may take advantage of emission credits to produce engines that are 

emitting at higher levels than competitive SD/I engines. 

The purpose of the FEL cap is to prevent the sale of very high-emitting engines. As 

discussed in Chapter 4 of the RIA, engine manufacturers already certify the majority of their 

engines using FELs well below the new FEL cap. This cap can be met through the use of simple 

four-stroke engines or direct-injection two-stroke engines. Bombardier did not comment on 

what alternative fuel they were referring to or why engines operating on this fuel could not meet 

the HC+NOx cap. In addition, Bombardier did not present a rationale why high-emitting engines 

using this fuel would be more acceptable than other high-emitting engines. Therefore, we are 

retaining the HC+NOx FEL cap for all OB/PWC Marine SI engines. 

3.6.4 Early credits for SD/I engines 

What Commenters Said: 

NMMA and Mercury Marine supported the Early Credit Program because it encourages 

SD/I manufacturers to expedite the introduction of catalyst-equipped engines nationwide earlier 

than what would be required in the regulation, which results in an environmental benefit. 

Mercury Marine noted that it plans to offer only catalyst-equipped versions of its Towed Sports 

(Water Ski Boats) engines in 2009, as this market is sensitive to CO emissions. NMMA and 

Mercury Marine also recommended that EPA allow manufacturers to earn early credits for 

engines that meet either the HC+NOx standard or the CO standard. 

NMMA and Mercury Marine commented that another important change that would need 

to be made to any Early Credit Program is to ensure that the timing for the program coincides 

with any adjustment to the implementation date for the standards. (In comments summarized in 

Section 3.2, NMMA and Mercury Marine commented that the 2009 model year implementation 

date for the SD/I exhaust standards was not realistic for the marine industry. NMMA and 

Mercury Marine recommended a 2010 compliance date for most of the SD/I engines, with a 

2011 implementation date for the GM replacement engines. NMMA also recommended a 2011 

implementation date for PWC engines installed in jet boats.) In order for an Early Credit 

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Chapter 3: Marine SI Engines 

Program to be useful, NMMA and Mercury Marine commented that EPA would need to adjust 

the period to reflect any changes made to the implementation date. 

CARB recommended against the adoption of early introduction multipliers for the 

generation of credits from SD/I engines. 

Although CARB opposes the banking and trading of emission credits, CARB commented 

that the prohibition in 1045.145(b)(6) against the early banking of emission credits for SD/I 

engines sold in California before 2009 should be amended or rescinded altogether if EPA decides 

to implement the ABT program as proposed. CARB understands that EPA does not want to 

allow credits to be generated from engines that are already required to meet cleaner emission 

standards in California. However, the blanket prohibition creates a disincentive for 

manufacturers to sell cleaner engines in California beyond what is already required. 

Furthermore, CARB noted that it does not allow credit banking or trading for spark-ignition 

recreational marine engines sold in California. Therefore, any credits earned from the early 

introduction of cleaner engines in California would not be subject to double-counting under 

EPA’s ABT program. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

CARB 0682 

Our Response: 

 With regard to the early credit provisions for SD/I engines, EPA is revising the program 

as a result of changes to the implementation dates for SD/I engines at or below 373 kW and 

changes to the emission standards for high-performance SD/I engines. As described in Section 

3.2.2, EPA is delaying implementation of the new standards for SD/I engines at or below 373 

kW until 2010 for most engines. This is a one year delay from the proposal and is in response to 

comments from manufacturers saying that additional lead time is needed to comply with the new 

standards. Because EPA has agreed that additional lead time is needed to comply with the new 

standards, we are revising the early credits provisions to allow manufacturers to earn early 

credits prior to 2010. However, given that manufacturers believe additional lead time is needed 

to comply, EPA does not believe that manufacturers should be able to earn bonus credits for 

certifying earlier than the 2010 timeframe. Therefore, EPA will allow manufacturers to earn 

early credits for SD/I engines below 373 kW that are certified before the applicable date in 2010 

or 2011. However, manufacturers will not be eligible to earn bonus credits on those engines. 

It should be noted that EPA is retaining a delayed implementation data of 2011 for smallvolume engine manufacturers to comply with the new standards for SD/I engines at or below 373 

kW, as proposed. Therefore, EPA is retaining the early credit provisions for small-volume 

engine manufacturers that certify earlier than 2011 to the new standards for SD/I engines at or 

below 373 kW, including the bonus factors that apply to the credit calculations. EPA believes it 

is appropriate to keep the bonus factors for small-volume engine manufacturers to encourage the 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

early introduction of new technologies from those manufacturers. Early credits, alone, may not 

be enough incentives for small businesses to certify early to the standards because they may run 

the risk of losing market share, during these early years, to lower cost product from competitors 

who choose not to certify early. Bonus credits help provide an additional incentive for the early 

introduction of low emission engines. 

EPA is retaining the requirement that engines must comply with both the HC+NOx 

standard and CO standard to qualify for early credits. The main purpose of the early credit 

program is to encourage the early introduction of engines complying with the new standards. 

EPA does not believe it is appropriate to provide credits for engines that comply with only one of 

the new standards, because that engine would not be a fully compliant product. In most cases, 

this should not be an issue because the anticipated emission-control technology for these engines 

may be used to meet both the new HC+NOx and CO standards. 

As described earlier in Section 3.4.1, EPA is finalizing a set of emission standards for 

high performance SD/I engines that do not include ABT provisions. As a result, the early credits 

provisions for high-performance SD/I engines have been deleted from the final regulations. 

In response to the comment on credits for engines sold in California, EPA is retaining the 

prohibition to generate credits from such engines, as proposed. SD/I engines sold in California 

are subject to exhaust emission standards adopted by CARB. EPA’s new exhaust standards will 

not apply to SD/I engines sold in California. Therefore, it is not appropriate to allow 

manufacturer to earn credits for engines subject to CARB standards, even if California does not 

allow credits from those engines to be banked. 

3.7 Other requirements 

3.7.1 Diagnostics 

What Commenters Said: 

NMMA and Mercury Marine commented that the proposed rule includes a requirement in 

§ 1045.110 that SD/I engines be equipped with an onboard diagnostic (OBD) system that will 

diagnose malfunctions of the emission control system. As proposed, § 1045.110(b) requires the 

OBD system to have a malfunction-indicator light (MIL) that must be readily visible. 72 Fed. 

Reg. at 28,265. The proposed regulatory text also states that the manufacturer “may use sound in 

addition to the light signal.” Id. (emphasis added). NMMA and Mercury do not oppose the 

requirement for an OBD system on SD/I engines to the extent that the requirement is not overly 

complex and is consistent with the California requirements. On the automotive side, OBD 

systems that meet California requirements are deemed to comply with the federal requirements. 

The OBD requirements in Part 86 provide “For light-duty vehicles, light-duty trucks, and heavyduty vehicles weighting 14,000 pounds GVWR or less, demonstration of compliance with 

California OBD II requirements (Title 13 California Code 1968.2 (13 CCR 1968.2)), as modified 

pursuant to CARB Mail-Out MSCD #02-11 (internet posting date October 7, 2002), shall satisfy 

the requirements of this section, except that compliance with 13 CCR 1968.2(e)(4.2.2)(C), 

pertaining to 0.02 inch evaporative leak detection, and 13 CCR 1968.2(d)(1.4), pertaining to 

tampering protection, are not required to satisfy the requirements of this section.” 40 C.F.R. § 

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Chapter 3: Marine SI Engines 

86.1806-05(j) (emphasis added). This “deemed to comply” provision has reduced the 

certification burden for the automotive industry and a similar approach is appropriate for the 

recreational marine industry. 

NMMA and Mercury continued to comment while proposed § 1045.110(a)(3) seems to 

include the “deemed to comply” concept discussed above by allowing for a diagnostic system 

approved by CARB for use with SD/I engines to “fully satisfy the requirements of [§ 

1045.110],” the requirement in that section for the MIL is inconsistent with the CARB 

regulations. In the CARB regulations, the OBD system must have “the capability to activate an 

audio or visual alert device located on the marine vessel to inform vessel occupants in the event 

of a malfunction . . . .” See CAL. CODE REGS. tit. 13, § 2444.2(b)(4) (2007) (emphasis added). 

EPA’s requirement of a MIL and possibly sound, if desired, is inconsistent with the CARB 

requirements and will impose an additional burden on manufacturers choosing the option of 

developing systems to meet both the California and future federal requirements. They 

recommend that § 1045.110(b) be revised as follows: 

(b) Use either a malfunction-indicator light (MIL) or sound. If a MIL is used, the MIL 

must be readily visible to the operator; it may be any color except red. When the MIL goes 

on, it must display ‘‘Check Engine,’’ ‘‘Service Engine Soon,’’ or a similar message that 

they approve. Instead of a MIL you may use sound. You may also use both a MIL and 

sound. In addition to the light signal. The MIL must go on or a sound must be made under 

each of these circumstances: 72 Fed. Reg. at 28,265. 

Given that CARB’s OBD requirements for SD/I engines commence in model year 2008, it is 

critical that EPA harmonize the federal OBD requirements with those that are already in place in 

California. Subsections 1045.110(g)(1) and (2) also require revision. As currently proposed, 

these two subsections incorporate by reference two separate ISO standards: “ISO 9141-2 Road 

vehicles—Diagnostic systems—Part 2: CARB requirements for interchange of digital 

information, February 1994;” and “ISO 14230-4 Road Vehicles—Diagnostic systems—Keyword 

Protocol 2000—Part 4: Requirements for emission-related systems, June 2000.” 72 Fed. Reg. at 

28,265. These standards are inappropriate for marine engines and should be replaced with a 

reference to an industry agreed to protocol developed by the American Boat and Yacht Council 

(ABYC). 

Indmar commented that the final item Indmar Products believes needs clarification is the 

OBD-M system. CARB allows for a MIL or a sound device. They believe this option is 

necessary to stay common with CARB. This may appear to be a minor detail but would have 

significant cost and logistics impact if we have to develop and sell different OBD-M systems for 

EPA and CARB. 

Volvo Penta opposes the use of ISO 9141-2 Road Vehicles and ISO 14230-4 Road 

Vehicles (1045.110g) for formats codes and connections. Volvo Penta has worked extensively 

with CARB, SAE and the other SD/I manufacturers to draft the new marine version of SAE J1939 for marine onboard diagnostic purposes. Therefore, Volvo Penta supports and encourages 

the EPA to harmonize the OBD requirements with CARB. Two different systems of format 

codes and connections to provide one set of data is prohibitively expensive, overly burdensome 

and confusing to Volvo Penta and marine technicians in the field. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Yamaha commented that current PWC engines for Federal or California compliance do 

not require the addition of OBD currently or the near future. To add OBD both physically and 

electronically for a small percentage of engines will be challenging, time consuming and very 

costly due to small production quantities. These units are used in Yamaha produced Jet Boats 

exclusively. As this is a vertically integrated product, Yamaha requests exemption relief from 

unnecessary OBD requirements until a stand alone Jet Boat (SD/I) engine is produced and 

certified as a 5gr engine. Yamaha anticipates that this can be achieved by M/Y 2011. 

Mercury Marine and NMMA commented that EPA states in § 1045.2, who is responsible 

for compliance, that [t]he requirements and prohibitions of this part apply to manufacturers of 

engines and fuel-system components as described in § 1045.1. The requirements of this part are 

generally addressed to manufacturers subject to this part’s requirements. The term ‘you’ 

generally means the certifying manufacturer. For provisions related to exhaust emissions this 

generally means the engine manufacturer . . . . For provisions related to certification with respect 

to evaporative emissions, this generally means the manufacturer of fuel-system components. 

Vessel manufacturers must meet applicable requirements as described in § 1045.20. The 

difficulty with this provision is that the recreational marine industry is not vertically integrated. 

This means that the SD/I engine manufacturer will supply the engine, the OBD system, 

connectors and installation instructions to the boat builder but will have no further role in 

assuring compliance with the regulatory requirements. While § 1045.20 addresses the obligations 

of the boat builder, engine manufacturers cannot guarantee that these requirements will be 

followed. In particular, proposed § 1045.20(d) requires boat builders to “follow all emissionrelated installation instructions from the certifying manufacturers as described [in the rule]. If 

you do not follow the installation instructions, we may consider your vessel to be not covered by 

the certificates of conformity. Introduction of such vessels into U.S. commerce violates 40 CFR 

1068.101.” 72 Fed. Reg. at 28,262 (proposed § 1045.20(d)). While § 1045.20 makes it explicit 

that boat builders must comply with the regulatory requirements, neither § 1045.2 nor § 1045.20 

provide a “safe harbor” for an engine manufacturer in the situations where the engine 

manufacturer complies with the regulations but the boat builder does not. 

To remedy this situation, Mercury Marine and NMMA recommend that EPA include in 

the final rule additional language in § 1045.2 that would hold an engine manufacturer harmless 

in the event that a boat builder fails to follow the requirements of the rule. This provision should 

state that as long as the engine manufacturer applies the emission control label, the OBD system, 

connectors, and emission-related installation instructions, the manufacturer is deemed to be in 

compliance with the requirements of the rule. This additional language will avoid any future 

confusion as to the compliance obligations of the engine manufacturer. 

NESCAUM commented that they support requiring engine diagnostics to ensure 

maintenance of stoichiometric control of air-to-fuel ratios. 

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Chapter 3: Marine SI Engines 

Letters: 

Commenter Document # 

NMMA 0688 

NESCAUM 0641 

Indmar 0667 

Volvo Penta 0708 

Yamaha 0721 

Mercury 0693 

Our Response: 

The final diagnostic requirement focuses solely on maintaining stoichiometric control of 

air-fuel ratios. This kind of design detects problems such as broken oxygen sensors, leaking 

exhaust pipes, fuel deposits, and other things that require maintenance to keep the engine at the 

proper air-fuel ratio. California ARB has adopted diagnostic requirements for SD/I engines that 

involve a more extensive system for monitoring catalyst performance and other parameters. We 

will accept a California-approved system as meeting EPA requirements. The final regulations 

direct manufacturers to follow standard practices defined in documents adopted recently by the 

Society of Automotive Engineers in SAE J1939-5. We agree with commenters that the 

malfunction indicator may be either a visual or audible cue and have made the corresponding 

change in our final rule. 

Jet boat engines that are certified using the emission-credit provisions of §1045.660 will 

not need a catalyst to meet emission standards. Because the proposed diagnostic requirements 

are geared toward closed-loop and catalyst-equipped engines, we agree that engines without 

these features should not need a diagnostic system. We have revised the regulation to apply the 

diagnostic requirement only to engines with catalysts. Jet-boat engines equipped with catalysts 

should be able to meet the proposed diagnostic requirements like any other SD/I engine. 

As noted in the comment, the regulations clearly state that vessel manufacturers are in 

violation if they fail to properly install diagnostic systems or otherwise do not follow the 

certifying engine manufacturer’s emission-related maintenance instructions. We believe the 

regulations do not need to go beyond this to create a safe harbor for engine manufacturers. 

Where an investigation establishes that the engine manufacturer has properly designed and 

produced an engine and communicated installation instructions to a vessel manufacturer, we 

would generally expect to enforce against the engine installer. On the other hand, there may be 

cases where the engine manufacturer has not properly designed or produced its engines or has 

not properly communicated installation instructions to vessel manufacturers (either by oversight 

or collusion). In these cases, we would not want to create an immunity for the engine 

manufacturer where we can in fact establish that the fault for misbuilt or otherwise noncompliant 

engines rests with the engine manufacturer. 

3.7.2 Torque broadcasting 

What Commenters Said: 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Mercury Marine, NMMA and BRP commented that also related to the option for in-field 

testing is the requirement in proposed §1045.115(b), Torque Broadcasting, for electronically 

controlled engines to “broadcast” their speed and output shaft torque. 72 Fed. Reg. at 28,265. 

This section requires that engines “broadcast” engine parameters so that they can be read by a 

remote device or “broadcast” directly to controller area networks. The rationale provided in the 

proposed provision is that the information is necessary for testing in the field. Id. The term 

“broadcast” is also used in § 1045.205(s) in the provision related to the information required in 

the certification application. This term is not defined in the proposed regulations and it is unclear 

what this term means. They can only assume that “broadcast” is supposed to mean the 

transmission of a signal of some kind. EPA does not specify how far the signal must be sent, 

what form is acceptable, or what the design specifications are for the “receivers” for such 

broadcasts. Since the equipment does not exist, and there is no currently understood 

methodology to determine torque, given the nature of propeller cavitation and slip, Mercury 

Marine, NMMA, and BRP request that EPA delete this provision. 

Volvo Penta opposes the need to broadcast engine torque. The proposal for 

manufacturers to broadcast engine torque is new, and has not been the subject of any discussion 

between EPA, NMMA and its member manufacturers. Volvo Penta has no experience with 

engine torque broadcast methods. Engine torque broadcast methodology is an emerging field 

without commonly accepted standards. Volvo Penta will require considerable time, resources 

and testing to create a robust and reliable method. If engine torque broadcast requirements are 

implemented through rulemaking, Volvo Penta will seek an exemption or postponement of 

implementation of the rule until after 2011. 

Honda commented that they do not understand how these sections apply specifically to 

outboards and PWCs. They assume that EPA may have intended that some of these sections 

apply only to SDI vessels. Outboards and PWC do not necessarily include any sensors or 

controls in a basic 4-stroke carbureted engine so including them in this requirement, especially 

torque value broadcasting, would be a complete change in their configuration clearly not 

anticipated in either the regulatory implementation date nor in the cost analysis associated with 

the emission reductions. Without engine management, a simple air / fuel map of the engine in the 

operating range would be sufficient to demonstrate that the engine will provide proper emission 

performance and not introduce any form of “defeat device”. 

Letters: 

Commenter Document # 

NMMA 0688 

Honda 0705 

Bombardier 0674 

Volvo Penta 0708 

Mercury 0693 

Our Response: 

As noted by Volvo, broadcasting for engines is an emerging field. For highway and 

nonroad diesel engines, we adopted requirements for engines to broadcast torque and speed 

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Chapter 3: Marine SI Engines 

values several years ago. We also adopted this requirement for Large SI engines in 2002. These 

systems are in the early stages of deployment, but there is a growing body of experience in this 

technology. Broadcasting simply involves electronic monitoring of engine parameters such that 

the engine’s electronic control unit can record values as needed to determine engine speed and 

torque at any given point in time. This is useful for performing field tests with portable 

analyzers. Speed measurements are straightforward. Since torque cannot be easily measured 

directly, manufacturers would need to do enough testing in the laboratory to establish 

relationships between torque and other measurable parameters such as throttle position and 

manifold absolute pressure. Once those relationships are established, the electronic control unit 

can be programmed with a look-up table to convert measured values to torque readings in real 

time. 

While we believe it is not difficult to incorporate broadcasting, we are aware that some 

development time is required to establish the look-up tables for converting engine operating 

parameters to torque values. We are also aware that the value of broadcasting for performing 

field tests with portable analyzers becomes prominent only after the point at which Not-toExceed standards have started to apply. We are therefore revising the regulation to require 

broadcasting starting with the 2013 model year. 

We believe it is not necessary to establish protocols for codes or other details for 

broadcasting. Manufacturers should be able to establish their own protocols for their engines. 

This development will be in tandem with the manufacturers’ effort to create diagnostic systems. 

In both cases there is a need for the electronic control unit to store values that can be retrieved by 

plugging in a laptop computer or some other type of reader. We expect the broadcast protocols 

to be based on those for the associated diagnostic systems. We are clarifying in the regulation 

that broadcasting needs to be done in a manner that allows for emission testing. For example, we 

believe it is not necessary to specify a frequency for broadcasting engine parameters, since 

testing can’t be performed if the broadcasting is not frequent enough to perform a valid test 

under the procedures specified in part 1065. 

We specifically object to Mercury’s reference to propeller cavitation and slip as an 

obstacle to proper torque broadcasting. Engine torque is determined by the load that is applied to 

(and the rotational force that is transmitted through) the crankshaft. Any vessel-based variables 

such as vessel speed, vessel direction (upstream or downstream), vessel load, or propeller 

cavitation or slip would not affect the internal engine relationships between output torque and the 

relevant parameters such as throttle position and manifold absolute pressure. 

We are limiting the broadcast requirements to electronically controlled engines. We 

agree that carbureted engines cannot be modified to comply with broadcasting requirements 

without fundamental modifications that go beyond the intended effect of setting new emission 

standards. However, we believe delaying the broadcast requirement until 2013 allows sufficient 

time for manufacturers to incorporate this upgrade for electronically controlled outboard and 

personal watercraft engines. As for SD/I engines, broadcasting will allow for greater flexibility 

in performing emission tests in the future. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

3.7.3 Crankcase emission controls 

What Commenters Said: 

NESCAUM commented that they support EPA’s proposal to require positive crankcase 

ventilation controls on SD/I engines. 

Letters: 

Commenter Document # 

NESCAUM 0641 

Our Response: 

We are adopting the crankcase requirements as proposed. 

3.8 Certification 

The following sections describe various issues related to the certification process that are 

specific to Marine SI engines. A few additional certification issues of more general interest are 

described in Section 1.3. 

3.8.1 Maintenance 

What Commenters Said: 

Volvo Penta opposes the proposal that prohibits manufacturers from scheduling critical 

emission related maintenance during useful life. Testing to date shows that there may be need to 

replace O2 sensors before the useful life period of the engine is reached. The O2 sensor 

manufacturer has made recommendations as to the type of O2 sensors to be used, but stated that 

marine applications are different and harsher than other applications where these sensors have 

been used successfully. On-going sensor durability testing has revealed significant numbers of 

O2 sensors out of specification before the engine’s useful life, as defined by the proposed rule. 

Moreover, our O2 sensor manufacturer has informed Volvo Penta that there is currently nothing 

available that will work any better in this application. 

Letters: 

Commenter Document # 

Volvo Penta 0708 

Our Response: 

There is no reason that oxygen sensors should fail before 480 hours of engine operation 

during service accumulation in the laboratory. We understand that in-use operating conditions 

may be so harsh that oxygen sensors will in some cases not survive through the useful life, but 

we believe that diagnostic systems are best suited to addressing this concern. A properly 

functioning diagnostic system would readily detect a failed oxygen sensor; the malfunction 

indicator would alert the operator. Since a failed oxygen sensor would lead to a loss in available 

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Chapter 3: Marine SI Engines 

power or increased fuel consumption or both, we believe owners would generally respond to the 

malfunction indicator by replacing the defective component. 

3.8.2 Carryover data 

What Commenters Said: 

BRP supports NMMA proposal to have carry-over engine families from the existing 

marine regulation and early-certified engine families meeting the exhaust emission standards of 

the proposed regulation be exempt from the proposed NTE test requirements and maximum test 

speed definition change through MY2013. It is necessary for BRP to phase in engine families to 

the new testing requirements over the next few model years. It is infeasible to re-test every 

engine family within the next couple years to verify compliance with the NTE proposal. In 

addition, allowing carry-over data to be exempt from the NTE and maximum test speed 

provisions will create an incentive for BRP and other manufacturers to certify their engine 

families to the new emissions standards in an earlier model year. 

Letters: 

Commenter Document # 

Bombardier 0674 

Our Response: 

BRP’s comments generally affirmed the rule as proposed. We have included these 

provisions in the final rule. 

3.8.3 Warranty 

What Commenters Said: 

NMMA and Mercury Marine commented that EPA notes in the preamble that the Agency 

is proposing updated warranty periods for the new standards. 72 Fed. Reg. 28,132. The new 

proposed emission-related warranty periods for PWC and OB engines in § 1045.120 are shorter 

in terms of hours but longer in terms of calendar years (or months). 72 Fed. Reg. at 28,132. For 

OB engines, EPA is proposing 5 years or 175 hours of operation, whichever comes first. 72 

Fed. Reg. at 28,132. For PWC engines, EPA proposes 30 months or 175 hours, whichever comes 

first. The new warranty provision also requires that an emission related warranty cannot be any 

shorter than any published warranty offered without charge for an engine or component. 72 Fed. 

Reg. 28,266 (proposed § 1045.120(b)). NMMA does not oppose the updated warranty periods 

for these engines nor does NMMA object to the requirement for the warranty period to track with 

any free, published warranty; however, § 1045.120(b) should be revised to clarify that “any 

published warranty” only applies to the particular engine and not the entire engine family. In 

addition, NMMA commented that EP A also needs to clarify that “any published warranty” does 

not include service contracts. Service contracts are those contracts that manufacturers offer for 

maintaining and repairing the engine beyond the warranty period. NMMA commented that while 

most service contracts require a fee, in some cases manufacturers may, as a promotion, offer 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

complimentary service contracts for a limited period of time to encourage the purchase of a new 

product or to clear inventory. A service contract, however, is not a warranty and should not be 

construed as such. 

To make the language clear, NMMA recommends that EPA revise § 1045.120(b) 

as follows: 

(b) Warranty period. Your emission-related warranty must be valid during the 

periods specified in this paragraph (b). You may offer an emission related warranty more 

generous than we require. The emission-related warranty for the engine may not be 

shorter than any published warranty you offer without charge for the engine and would 

only apply to the engine and not the engine family. Similarly, the emission-related 

warranty for any component may not be shorter than any published warranty you offer 

without charge for that component. A service contract is not a warranty. If an engine has 

no hour meter, we base the warranty periods in this paragraph (b) only on the engine’s 

age (in years). The warranty period begins when the engine is placed into service. These 

changes will help clarify that only the engine and not the engine family is affected by any 

published warranty and that service contracts are not to be confused with warranties. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

Our Response: 

We agree that extended warranties offered at no additional charge should be limited to 

those components or engines that are the subject of the extended warranty. We have revised the 

regulation to emphasize that the extended warranty does not apply more broadly than for the 

particular engines that are the subject of the extended warranty. We believe it is not helpful to 

introduce a distinction between no-cost service contracts and warranties because that would 

likely become a loophole that allows manufacturers to avoid warranty requirements. In 

particular, if a manufacturer offers a no-cost service contract, that represents an expectation that 

the engine will operate consistently over a certain period. We do not understand or accept the 

logical construct that would say the engine manufacturer should pay for defects that are not 

emission-related, but that they are not responsible for defects that are emission-related. We are 

therefore adopting these warranty requirements as proposed. 

3.8.4 Family criteria 

What Commenters Said: 

NMMA and Mercury commented that for SD/I certification purposes, EPA is proposing 

in § 1045.230(b) to require manufacturers to group engines in the same family if they are the 

same in all the following respects: combustion cycle and fuel; cooling system (e.g., raw water, 

separate circuit cooling); method of air aspiration; number, location, volume and composition of 

catalytic converters; the number arrangement, and approximate bore diameter of cylinders; 

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Chapter 3: Marine SI Engines 

method of control for engine operation; numerical level of the emission standards that apply to 

the engine. 72 Fed. Reg. 28,271. While this list is very similar to what is currently required for 

outboard and personal watercraft in § 91.115, the SD/I engine segment has unique characteristics 

and requires a more flexible approach that will prevent the creation of a large number of engine 

families and reduce the certification and administrative burdens placed on these manufacturers 

(e.g., double certification tests, durability tests, recordkeeping, etc.). To that end, in the final rule, 

NMMA and Mercury comment that EPA should revise §1045.230(b) to reduce the number of 

characteristics that must be identical for purposes of determining engine families. 

In particular, NMMA and Mercury stated that the requirements for identical cooling 

systems and bore diameter should be removed because these are overly restrictive in practical 

effect and will not have an impact on exhaust emissions from SD/I engines. Exhaust emissions 

do not vary for thermostatically controlled engines regardless of whether the engine is cooled 

with raw or fresh water. Also of significance is that CARB does not require manufacturers to use 

the cooling system as a criterion for distinguishing among engine families. NMMA and Mercury 

commented as for the bore diameter, there are situations where similar engines of varying 

displacements should be included in the same engine family. For example, GM’s 5.0L and 5.7L 

engines vary only in displacement and share common induction systems, number and 

arrangement of cylinders, cylinder heads, and external marinization components, including 

exhaust equipped catalysts. These engines have been classified historically in one engine family 

and have the same emissions characteristics. For these reasons, NMMA and Mercury believe that 

EPA must delete these criteria for SD/I engines from § 1045.230(b). 

NMMA and Mercury Marine commented for PWC/OB, EPA proposes requirements for 

dividing product lines into engine families in § 1045.230. As discussed in the comments related 

to the requirements for SD/I engines, the list of characteristics contained in proposed § 

1045.230(b) is similar to what is in § 91.115; however, there are several requirements, e.g., the 

bore diameter and cooling systems, that will require SD/I manufacturers to establish too many 

engine families as noted above and are not a meaningful criteria for PWC or OB engines either. 

There are also several differences between § 1045.230(b) and § 91.115 with regard to the 

inclusion of the numerical level of the emissions standards and method of control for engine 

operation in the characteristics that must be identical. 72 Fed. Reg. 28,271 (proposed § 

1045.230(b)(6) and (7)). In light of these differences and the fact that OB and PWC engine 

manufacturers have been following § 91.115 for over a decade, NMMA and Mercury Marine 

recommend that EPA substitute portions of § 91.115(c) and (d) for the corresponding language 

in § 1045.230 with the changes recommended for SD/I. The following redline is provided by 

NMMA and Mercury to show how this provision should be revised. 

§ 1045.230 How do I select engine families? 

a. For purposes of certification, divide your product line into families of engines that are expected to have 

similar emission characteristics throughout the useful life as described in this section. Your engine family 

is limited to a single model year. 

b. To be classed in the same engine family, engines must be identical in all of the following applicable 

respects: 

(1) The combustion cycle; 

(2) The cylinder configuration (inline, vee, opposed, and so forth); 

(3) The number of cylinders; 

(4) The number of catalytic converters, location; volume, and composition; and 

(5) The thermal reactor characteristics. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Group engines in the same engine family if they are the same in all the following aspects: 

(1) The combustion cycle and fuel. 

(2) The cooling system (for example, raw-water vs. separate-circuit cooling). 

(3) Method of air aspiration (for example, turbocharged vs. naturally aspirated). 

(4) The number, location, volume, and composition of catalytic converters. 

(5) The number, arrangement, and approximate bore diameter of cylinders. 

(6) Method of control for engine operation, other than governing (i.e., mechanical or electronic). 

(7) The numerical level of the emission standards that apply to the engine. 

c. At the manufacturer’s request, engines identical in all the respects listed in paragraph (b) of this section 

may be further divided into different engine families if the Administrator determines that they may be 

expected to have different emission characteristics. This determination is based upon the consideration of 

features such as: 

(1) The bore and stroke; 

(2) The combustion chamber configuration; 

(3) The intake and exhaust timing method of actuation (poppet valve, reed valve, rotary valve, and so 

forth); 

(4) The intake and exhaust valve or port sizes, as applicable; 

(5) The fuel system; 

(6) The exhaust system; and 

(7) The method of air aspiration. 

You may subdivide a group of engines that is identical under paragraph (b) of this section into different engine 

families if you show the expected emission characteristics are different during the useful life. 

d. You may group engines that are not identical with respect to the things listed in paragraph (b) of this 

section in the same engine family, as follows: 

(1) In unusual circumstances, you may group such engines in the same engine family if you show that 

their emission characteristics during the useful life will be similar. 

(2) If you are a small-volume engine manufacturer, you may group all your high-performance engines into 

a single engine family. 

(3) The provisions of this paragraph (ed) do not exempt any engines from meeting all the emission 

standards and requirements in subpart B of this part. 

NMMA commented that these recommended revisions harmonize the existing 

requirements in § 91.115 with the newly proposed § 1045.230. This redline also reflects the 

recommendations discussed above related to SD/I engine families. 

Honda commented regarding the Engine Family Determination for Outboard Engines and 

PWCs. Honda suggests that the criteria for engine family selection outlined in Section 

1045.230(7) of the proposal be deleted from the final rule. Section 1045.230 of the proposal 

makes “the numerical level of the emission standard” a family determination criteria. The 

numerical standard level would mean that each engine horsepower would be a separate family. 

This is unlike 40 CFR Part 91 where two engine models (75 & 90 hp for example) are created 

from one engine (same displacement / block and head) and are in the same family. This change 

would be completely contrary to the intended purpose of the family concept (similar engine with 

similar emission characteristics). Perhaps this was incorrectly carried over from another 

regulation where different classes with different displacement categories meet numerically 

different standards. 

Indmar commented in §1045.230 (b) 2 the cooling system (raw-water vs. separate-circuit 

cooling) could be a family discriminator. This would double the number of engine families for 

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them with no value added. Indmar offers most of their engines with raw-water or fresh-water 

cooling. The control temperature for both these applications is 165 degrees Fahrenheit. The 

exhaust manifolds are heated for both fresh and raw water systems so the exhaust gas feed 

stream to the catalyst is not impacted differently with either system. The emissions of the engine 

will not change with either cooling system. Also of significance is that CARB does not require 

manufacturers to use the cooling system as a criterion for distinguishing among engine families. 

Suzuki commented that EPA has proposed to revise the requirements for how to group 

products into common engine families to include a new provision of "approximate bore 

diameter" as a requirement for engine family grouping. Suzuki is concerned that this new 

provision will inappropriately require the creation of additional engines families that otherwise 

could be grouped together if the existing engine family grouping criteria specified in §91 .115 

were employed. They are also concerned that the judgment criteria could be confusing to 

implement from a certification-planning viewpoint. Suzuki requests that EPA reconsider the 

need to include this revision in the regulation. Should EPA decide to proceed with the proposed 

revision, Suzuki requests that the regulatory language be revised to allow the Agency to have 

discretion to approve the grouping of engines of dissimilar bore diameters if a manufacturer can 

show that the proposed grouping is in agreement with good engineering practices. 

Volvo Penta opposes the family aspects (families) as outlined in the NPRM. Volvo Penta 

commented that the proposed NPRM aspects will create too many engine families requiring a 

multiplicity of certification testing and documentation with no resulting emissions reduction. The 

proposal, therefore, is unnecessarily burdensome. Volvo Penta is a custom marinizer of General 

Motors (GM) produced engine blocks. Traditionally, Volvo Penta arranged engine families for 

emissions classification by GM’s engine block types and fuel intake systems. As the engines are 

catalyzed, the fuel intake systems become the same, thereby eliminating fuel intake type as a 

family discriminator. Volvo Penta’s current engine families for emissions purposes are: 

• 3.0 I4 Carbureted 

• 4.3 V6 Carbureted 

• 4.3 V6 EFI 

• 5.0 V8 Carbureted 

• 5.0 V8 EFI 

• 5.7 V8 EFI (All models EFI) 

• 8.1 V8 EFI (All models EFI) 

Beginning with California in 2008 Volvo Penta will identify the following engine families: 

• 3.0 I4 (EFI + Cat) 

• 4.3 V6 (Carbureted) 

• 4.3 V6 (EFI) 

• 5.0 & 5.7 V8 (all models EFI + Cat) 

• 8.1 (all models EFI + Cat) 

They anticipate that by 2011 the Volvo Penta engine families will include: 

• 3.0 I4 (EFI + Cat) 

• 4.1 V6 (all models EFI + Cat) 

• 5.0 & 5.7 V8 (all models EFI + Cat) 

• 6.0 SC V8 (all models EFI + Cat) 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Volvo Penta will continue to offer multiple horsepower and cooling system options 

within each family as they do today. The least compliant (i.e., “dirtiest”) engine within each 

family is used for California and EU compliance certification purposes. That process ensures that 

all engines within a particular family (however defined) meet the emissions criteria required. 

Multiple families add expense without benefit. 

Pleasurecraft Marine in a hearing commented that §1045.230 outlines the criteria for 

defining engine families. There are two areas that Pleasurecraft Marine commented need 

reconsideration. Those areas are: 

• Line Item 2, the cooling system (§1045.230(b)(2) 

• Line Item 5, the number, location, volume, and approximate bore diameter of the 

cylinders (§1045.230 (b)(5)). 

Pleasurecraft Marine commented regarding Line Item 2, segregating engine families by 

their cooling system accomplishes nothing more than doubling the number of engine families. 

Emissions will not vary, for thermostatically controlled engines regardless of whether the engine 

is raw or fresh water-cooled, therefore, the cooling system should not be a factor in determining 

engine families. 

Pleasurecraft Marine commented regarding Line Item 5, there are circumstances where 

similar engines of different displacements should be included in a common engine family. An 

example would be the General Motors 5.0 and 5.7 liter engines. These engines vary only in 

displacement and share common induction systems, number and arrangement of cylinders, 

cylinder heads, and external marinization components including exhaust equipped with catalyst. 

Historically General Motors, who designed these engines, has classified them as one family. If 

the larger displacement 5.7L will meet emissions standards it is safe to say that the 5.OL will do 

so as well. Classifying these engines as one family, as they should be, will save small businesses, 

such as theirs, tens of thousands of dollars in unnecessary certification cost. 

Letters: 

Commenter Document # 

NMMA 0688 

NMMA 0688 

Honda 0705 

Indmar 0667 

Volvo Penta 0708 

Mercury 0693 

Pleasurecraft Marine (hearing) 0642 

Our Response: 

We agree that engine families should not be differentiated based on the cooling system. 

The current regulations in part 91 include this specification, but it seems that the relative 

uniformity of designs for outboard and personal watercraft engines has prevented this from being 

an issue. We are revising the regulations to exclude the cooling system from §1045.230 for all 

Marine SI engines. 

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The intended effect of including the applicable emission standard to differentiate engine 

families was two-fold. First, this would prevent SD/I engines from being included in the same 

engine family with OB/PWC engines. Second, this would prevent engines certified to different 

Family Emission Limits from being in the same engine family. Selecting different Family 

Emission Limits for engines that are subject to identical standards inherently implies that the 

engines will not have similar emission characteristics throughout the useful life, which is the 

fundamental purpose of establishing engine families, as expressed in §1045.230(a). Contrary to 

the concern raised by Honda, the regulatory language does not prevent a manufacturer from 

including different power ratings in the same engine family. As specified in §1045.103, the 

applicable emission standard for an OB/PWC engine family is based on the maximum engine 

power for the engine family as described in §1045.140. Section §1045.140 acknowledges that an 

engine family may have multiple power ratings within the family by specifying that the 

maximum engine power for an engine family is the production-weighted average of each engine 

configuration within the engine family. Therefore, under the regulations for OB/PWC engines in 

part 1045, manufacturers will be able to include different power ratings in a given engine family 

just as they currently can do under the part 91 regulations. 

We believe the regulation should require that engines in a single family have the same 

“approximate bore diameter.” This lays out the general expectation that engines with 

substantially different displacement values cannot be assumed to have the same emission 

characteristics throughout the useful life. Basing family differentiation on approximate bore 

diameter also allows us the flexibility of including engine models in the same family if the 

difference in displacement is not so great. We have traditionally applied this principle by 

allowing combined families where the smaller engine has a displacement that is within 15 

percent of the displacement of the larger engine. This would, for example, allow the 5.0 and 5.7 

liter engines to be grouped into the same engine family. We would have the discretion to 

broaden this threshold if a manufacturer could demonstrate that two engine models would have 

similar emission characteristics throughout the useful life. Conversely, we would be able to 

narrow this threshold if necessary to prevent inappropriate groupings of engines. 

3.9 Test procedures 

3.9.1 Maximum test speed 

What Commenters Said: 

NMMA commented that EPA proposes a definition for “maximum test speed” as the 

“single point on an engine’s maximum-power versus speed curve that lies farthest away from the 

zero-power, zero-speed point on a normalized maximum-power versus speed plot.” 72 Fed. Reg. 

at 28,133. EPA claims that the definition for maximum test speed establishes objective 

procedures for determining this parameter. NMMA’s concern with the proposed definition is 

that it fails to incorporate the SAE J1228 and the ISO 8665 standards that are currently used by 

industry. In addition, the new term would have the effect of overly complicating testing and 

certification. First, it will result in having to run different tests and data points for EPA, CARB 

and the EU. Second, it is important to note that the power curve is different for engines with 

different horsepower within an engine family. Thus, a manufacturer would have to run all these 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

different power curves, determine the test points for each engine model in the engine family, run 

an emissions test on each with unique test points to determine which is the highest emitting 

engine, and then certify that engine. Finally, another consideration is that manufacturers use, as 

the Mode 1 point, the speed at which the boat should be “propped.” For these reasons, NMMA 

recommends that EPA use the current certification method of rated speed and rated power in the 

final rule. 

Mercury Marine commented that EPA proposes a definition for “maximum test speed” as 

the “single point on an engine’s maximum-power versus speed curve that lies farthest away from 

the zero-power, zero-speed point on a normalized maximum-power versus speed plot.” 72 Fed. 

Reg. at 28,133. EPA claims that the definition for maximum test speed establishes objective 

procedures for determining this parameter. Mercury Marine’s concern with the proposed 

definition is that it fails to incorporate SAE 1228 and ISO 8665 standards that are currently used 

by industry, which calls for using the midpoint of the maximum rpm range. This will mean that 

an EPA certification will no longer be the same as CARB’s or the EU’s. This is a major move 

away from harmonization of standards and will generate extra cost and work for no appreciable 

gain. In addition, on some engines, this will move the Mode 1 point to the maximum allowable 

rpm for the engine. Boat builder and customer practice is to prop the boat at the midpoint. 

Therefore, this makes the test less representative of real world operation. Propping the boat at 

the maximum allowable rpm would create a situation, under some operating conditions, where 

the engine would over-rev and bounce on and off of the rev limiter, which is set just slightly 

above the maximum allowable rpm. 

Mercury Marine submitted an email stating that they are having great difficulty 

understanding the Max Test Speed Issue. The attached normalized speed and power graph are for 

the 75-90-115 Hp Optimax (DI 2 stroke). The engine has a maximum operating speed range of 

5000 - 5750 rpm. If they are understanding this correctly, they would have to use 5750 rpm as 

the Mode 1 point for the 90 and 115. Is that correct? (Not sure about what point they use for the 

75.) If so, they would be testing the engine in a way that no boatbuilder would ever prop it to, 

and no owner would ever use it that way. Their instructions are to prop the boat to the midpoint 

of the range and virtually everyone does that. To prop it to run 5750 rpm, you would have a 

situation where you could potentially be bouncing off the rev. limiter at WOT (it is set at 5850 

rpm). (data and graph also added- see package). 

 Bombardier commented that EPA proposes a definition for “maximum test speed” as the 

“single point on an engine’s maximum-power versus speed curve that lies farthest away from the 

zero-power, zero-speed point on a normalized maximum-power versus speed plot.” EPA claims 

that the definition for maximum test speed establishes objective procedures for determining this 

parameter. BRP is concerned the proposed definition change fails to align with the SAE J1228 

and the ISO 8665 standards that are currently used by industry. 

BRP outboard engines are 'propped' around the wide open throttle point on the ICOMIA 

test cycle. This point optimizes the engine performance, and all boat builders are instructed to 

prop the engine within an RPM range of this test point. Since this point offers the greatest engine 

performance and flexibility, propping a boat outside of the recommended RPM range can void 

the warranty. Consequently boat builders will insure the engine is propped within the 

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Chapter 3: Marine SI Engines 

recommended RPM range. By changing the definition of maximum test speed, EPA will be 

changing the wide open throttle point for many engine technologies. Since this point is utilized to 

calculate the other test points along the ICOMIA cycle, this will force a manufacturer to certify 

an outboard engine family using test points which will not represent the emissions of an in-use 

engine. 

BRP continued that in addition, the new definition would force a manufacturer to run an 

additional power curve test prior to conducting any emission test to determine the applicable test 

points. This would have the effect of overly complicating testing and certification. The proposed 

maximum test speed definition change will result in having to run different tests and data points 

for EPA, CARB and the EU which increases a manufacturer's test burden and costs. For these 

reasons, BRP recommends that EPA maintain the current certification method of rated speed and 

rated power. 

Volvo Penta disagrees with the need to establish a Maximum Test Speed. In reality, the 

proposed test is contrary to the EPA’s stated goal of corresponding in use operation. Rated speed 

is determined by the point that that the engine makes maximum power. Most if not all 

manufacturers have a recommended engine speed range that typically is a band of about 400 

RPM. The boat manufacturers will select the appropriate propeller to meet the midpoint of the 

RPM band (rated speed) which is the max boat speed point with a normal boat load. The boat 

may run 200 RPM higher with a light boat load but the boat speed will not necessarily be greater. 

With a heavy load, the boat will run 200 RPM lower and will lose some speed. Most engine 

manufacturers set RPM limiters approximately 100 RPM above the upper end value of the range 

to prevent engine damage due to over-trimming or propeller ventilation. 

Suzuki commented that EPA is proposing to revise the definition of "maximum test 

speed" as the "single point on an engine's maximum-power versus speed curve that lies farthest 

away from the zero-power, zero speed point on a normalized maximum-power versus speed 

plot." This definition would deviate from currently accepted industry practice used in the US and 

internationally, which is to follow standards defined by SAE J1228 and ISO 8665. 

Suzuki believes EPA's proposed revision is unnecessary and could require the creation of 

Federal specific test data points, with a separate set of test points for engines certified for in 

California and international markets . They request that EPA reconsider their proposed revision, 

and adopt the currently acceptable standards set by SAE J1228 and ISO 8665. 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Mercury Marine 0717 

Volvo Penta 0708 

Mercury 0693 

Suzuki 0698 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

 The manufacturers express their interest in continuing to determine maximum test speed 

as specified in the current regulations and the relevant SAE and ISO standards. However, this is 

misleading, since the requirement under all these testing protocols is for manufacturers to declare 

the maximum test speed of an engine based on its rated power, without providing any objective 

criteria for establishing the point of rated power. We believe manufacturers generally choose a 

maximum test speed that is consistent with the way engines operate in use, but under the current 

program we would have little or no ability to insist that an engine’s maximum test speed and 

rated power point be reasonably representative of an in-use configuration. 

The importance for adopting objective criteria for selecting maximum test speed grows 

significantly with Not-to-Exceed standards. The upper end of the NTE zone is based on 

maximum test speed, so manufacturers would have a significant incentive to declare a maximum 

test speed as low as possible. It is very common for engine manufacturers to specify a prop 

range of 1000 rpm. This shows that there is considerable latitude in fitting propellers that would 

result in a wide range of expected speed and power values. Allowing manufacturers to declare 

lower values for maximum test speed would shift the whole NTE zone toward lower speeds, 

potentially causing large areas of common engine operation under the engine map to be “out of 

bounds” for testing. 

The proposed approach from part 1065 is used for a wide range of engine categories to 

reliably locate maximum test speed at a point on the engine map such to maximize available 

power over a range of operating speeds. The current regulations specify that the value selected 

for maximum test speed must be within 2.5 percent of the calculated value. For Marine SI 

engines operating up to about 6000 rpm, this translates to a range of ±150 rpm. For many 

engines that are not used for marine propulsion, the calculated value of maximum test speed is 

the midpoint of a range of values the manufacturer could select for governing off of the power 

map. However, as noted in the comments, Marine SI engines need to be fitted with a propeller 

such that the nominal value for achieving maximum power needs to be away from the point at 

which the governor (or rev limiter) starts to cut engine power. We therefore believe it is 

appropriate to specify for Marine SI engines that the declared value for maximum test speed may 

be within 500 rpm of the calculated value. For example, if maximum test speed is calculated to 

be 6000 rpm based on an engine’s power map, the manufacturer could declare a maximum test 

speed as low as 5500 rpm. Based on a range of power maps shared confidentially by multiple 

manufacturers, this approach would allow manufacturers in most or all cases to select a 

maximum test at the maximum power point or at the midpoint of the specified prop range. 

In addition, we are adding a provision to the regulations to specify that the maximum 

speed of the NTE zone for in-field testing is based on the engine’s actual maximum operating 

speed. As long as the engine is installed consistent with the engine manufacturer’s instructions 

regarding prop specifications, we would be able to perform valid tests throughout the NTE zone 

based on the engine’s actual maximum operating speed. This would address our concern that 

many owners and boat builders may not be so careful to install a propeller that targets the 

midpoint of the speed range specified by the manufacturer. This approach allows manufacturers 

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Chapter 3: Marine SI Engines 

to design for the nominal value (and probably the most common in-use configuration) for 

certification without overlooking the range of in-use experiences. 

If boat builders or owners install a propeller outside of the engine manufacturer’s 

specified range, we would consider these engines to be “not properly maintained and used”, 

which would make them ineligible for compliance testing in that configuration. Note that we 

would generally consider boat builders to be guilty of violating the tampering prohibition if they 

do not follow the engine manufacturer’s specifications for propellers. If we wanted to test an 

engine and found that the propeller was outside of the manufacturer’s specifications, we would 

arrange for replacing the propeller to be within the manufacturer’s specified range. Similarly, if 

the propeller were worn or damaged such that the engine no longer operated within the 

manufacturer’s specifications, we would replace the propeller before testing. We would also not 

consider a test to be valid if the vessel’s characteristics had changed such that the engine no 

longer operated within the manufacturer’s specifications (such as through wear, modification, or 

lack of cleaning). 

We would expect manufacturers to declare this same value for maximum test speed for 

testing to demonstrate compliance with California or European standards, so we are not adopting 

a provision that would cause a need for duplicate testing for non-harmonized programs. It is 

true that manufacturers would need to run an engine map for each engine, but we expect that this 

is already common practice to establish the engine’s power characteristics and determine the 

recommended prop range. Manufacturers may continue to use engineering judgment to establish 

the worst-case configuration in an engine family for selecting a test engine, as is done today. 

3.9.2 Field-testing procedures 

What Commenters Said: 

NMMA and Mercury Marine commented that EPA proposes in § 1045.401(a) and § 

1045.410(f)(2) in-use testing provisions to allow optional field testing instead of laboratory 

testing. This same option also is included in the provisions for certification testing in § 1045.515. 

As noted earlier in their comments above on the optional field-testing for SD/I engines, this 

option does not provide additional flexibility for PWC and OB engine manufacturers because it 

has no meaningful impact. The equipment needed to conduct field testing does not exist and 

there are no standardized requirements for ports in which to plug the devices. NMMA and 

Mercury recommend that EPA delete the references to field testing until such equipment is 

commercially available and has proven to be accurate and consistent. 

Bombardier commented that EPA proposes in 40 CFR 1045.401(a) and 40 CFR 

1045.410(f)(2) of the in-use testing provisions to allow optional field testing instead of 

laboratory testing. This same option also is included in the provisions for certification testing in 

40 CFR 1045.515. The equipment needed to conduct field testing does not exist and there are no 

standardized requirements for ports in which to plug the devices. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Bombardier continued as discussed in the NMMA comments, adopting the field testing 

requirements of 40 CFR 1065 is not technically feasible for the marine industry. The equipment 

necessary to conduct accurate measurements has not been verified for use in marine products. 

BRP is concerned that less accurate field sampling equipment could be used to determine if an 

engine is in compliance with the proposed emission requirements. BRP believes any emission 

testing needs to be performed utilizing the test procedures and equipment required for 

certification. 

BRP recommends that EPA delete the references to field testing until such equipment is 

commercially available and has proven to be accurate and consistent. 

Volvo Penta opposes any alternate field test procedures. Volvo Penta has not undergone 

experience with, or consideration of, such procedures. Volvo Penta does not understand the 

purpose for this proposal. If the intention is to be able to measure emissions from a given engine, 

then we feel that the proposal is fraught with potential problems. Circumstances such as, varying 

exhaust back pressure changing engine loads (due to wind, current and tides), unknown fuel 

properties, and variation in portable analyzers can have an effect on the results. Moreover, the 

engine OBD effectively captures the emissions history for an engine without the need for 

additional testing procedures or methodology. 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Volvo Penta 0708 

Mercury 0693 

Our Response: 

Equipment is available today for measuring emissions from engines while they remain 

installed in a marine application. We believe it is important to be able to make these 

measurements and are adopting provisions broadly across our programs to allow for this. These 

measurements allow us to most effectively characterize the true emissions performance from inuse engines. Also, in the case of personal watercraft, manufacturers may be able to realize 

substantial savings by performing their required in-use testing using field-testing procedures so 

they don’t have to destroy the vessel to remove the engine for testing. 

Part 1065 describes the accuracy requirements for the portable analyzers associated with 

field-testing procedures. The requirements generally allow for somewhat less accuracy and 

precision. We understand that commercial fuels may also differ somewhat from certification 

fuels in a way that could affect emissions. We also agree that wind, current, and other factors 

can change the way the engine operates; this is fundamental to the NTE approach in which we 

require manufacturers to design for engine operation away from the discrete test modes for 

certification. We are not aware of the affect that tides have on engine operation. In any case, we 

are adopting NTE multipliers that take into account all these factors for potentially higher or 

more variable emissions associated with field-testing measurements. Manufacturers may choose 

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Chapter 3: Marine SI Engines 

to perform tests with portable analyzers at certification to establish a correlation with 

conventional laboratory measurements. 

Diagnostic systems are helpful for detecting defects and the need for engine maintenance. 

They are not effective for evaluating the performance or effectiveness of properly functioning 

engines. Measuring emissions from in-use engines is the best way to establish whether certified 

engines are achieving the intended level of reduced emissions. 

We believe it is not necessary to specify a standardized access port for routing exhaust 

emissions to a portable analyzer. It should not be difficult to mate a range of access ports to a 

given analyzer with any necessary fittings. Also, over time we believe manufacturers will be 

able to communicate and cooperate as needed to establish a single protocol, or at least a small 

number of protocols, for mating analyzers with exhaust ports. 

3.9.3 1065 issues for Marine 

What Commenters Said: 

Honda also recommends a review of the change in test procedure to determine if there is 

any measurement improvement or emission benefit that warrants the cost of the equipment 

upgrade that may be necessary to make these measurements according to Part 1065. 

Letters: 

Commenter Document # 

Honda 0705 

Our Response: 

As described in Section 2.5, we believe the test procedures specified in part 1065 have 

been reviewed very carefully to reflect a consensus regarding appropriate equipment 

specifications, calibrations, and procedures. Many manufacturers testing under part 91 today 

will have to make little or no change to meet the part 1065 requirements. Some manufacturers 

may find that they need to upgrade a measurement instrument or incorporate some changes to 

their current practice. We have included an estimate of the cost of making these changes in the 

Final Regulatory Impact Analysis. 

3.9.4 Humidity correction 

What Commenters Said: 

Mercury Marine commented that the current rule allows for NOx correction for humidity, 

as it does for California. Therefore, they have not needed humidity control in their test cells. It 

appears that this provision has been eliminated in the proposed rule. This will require Mercury to 

add humidity controls to their test cells, at great expense. They therefore request that NOx 

correction for humidity be included in this rule. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

Mercury 0693 

Our Response: 

We agree that the humidity corrections specified in part 1065 should be available for 

Marine SI engines. We have revised the regulations in part 1045 to specifically allow this. 

3.10 Production-line testing 

3.10.1 Need for PLT for SD/I engines 

What Commenters Said: 

NMMA commented that EPA, however, is proposing to require production line testing 

(PLT) for SD/I engines in § 1045.301. NMMA urges EPA to reconsider requiring SD/I engine 

manufacturers to perform PLT. The CARB regulations do not impose PLT requirements on SD/I 

engine manufacturers. It is critical for this industry that EPA makes the federal and California 

programs as seamless as possible to eliminate the additional burden and cost caused by 

inconsistent regulatory requirements. It is also important to note that above and beyond the 

actual costs of the tests themselves, the cost of an emissions bench assuming one is even 

available) and a dynamometer can average around $500,000. Furthermore, there are significant 

“brick and mortar” costs associated with the proposed PLT requirements that EPA’s proposal 

fails to take into account. It is our understanding that NMMA members will provide in their 

separate comments additional detail on the extensive costs that will be imposed by the proposed 

PLT requirements. 

NMMA continued that in addition, as noted above, the requirement to install an OBD 

system as specified in § 1045.110 will ensure that an owner is notified in the field of any 

problem with the emission control system. To that end, NMMA recommends that EPA insert a 

third provision in § 1045.301(a) as follows: 

§ 1045.301 When must I test my production-line engines? 

(a) If you produce engines that are subject to the requirements of this part, you must test 

them as described in this subpart, except as follows: 

(1) Small-volume engine manufacturers may omit testing under this subpart. 

(2) You may exempt engine families with a projected U.S.-directed production 

volume below 150 units from routine testing under this subpart. Request this 

exemption in the application for certification and include your basis for projecting 

a production volume below 150 units. You must promptly notify us if your actual 

production exceeds 150 units during the model year. If you exceed the production 

limit or if there is evidence of a nonconformity, we may require you to test 

production- line 12 engines under this subpart, or under 40 CFR part 1068, 

subpart E, even if we have approved an exemption under this paragraph (a)(2). 

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(3) Engines equipped with an on-board diagnostic system meeting the 

requirements in § 1045.110 of this subpart are exempt from the requirements of 

this section. 

NMMA continued to comment that this additional language should be included in the rule to 

reduce the regulatory burden imposed on engine manufacturers by the rule. 

Mercury Marine urges EPA to reconsider requiring SD/I engine manufacturers to 

perform PLT. The CARB regulations do not impose PLT requirements on SD/I engine 

manufacturers. It is critical for this industry that EPA makes the Federal and California programs 

as seamless as possible to eliminate the additional burden caused by inconsistent regulatory 

requirements. 

To implement PLT, Mercury Marine would need to add one, or more, new emissions test 

cells, including instrumentation benches, and dynamometers. The equipment costs alone are in 

the $600,000 range, and building the facilities, including climate control, air handling, etc. could 

easily equal that figure. Therefore, they are looking at over $1M per test cell. Further, there will 

be impacts on plant emissions and permitting that will further drive up costs. If an engine was 

built incorrectly, the OBD system would detect the problem, so there is no emissions benefit to 

this extremely costly requirement. 

Indmar commented that they would like to see End of Line testing not required for all 

SD/I engines. The OBDM system implemented for SD/I engines will catch and identify any 

engine operating problem that might result in non emission compliant engines. All emission 

components as well as the operation of the catalytic converter are monitored. Any engine with a 

problem will be caught at end of line run check and corrected before the engine is sold to 

commerce. This procedure would be common with CARB. 

Volvo Penta opposes production line testing (PLT) for SD/I engines. 

• All SD/I engines (except Hi-Performance) will be equipped with catalytic converters with 

feed back loop controls with on-board diagnostics (OBD) that constantly monitor the 

emission control systems of these engines as they run. In the event of an emission system 

malfunction, OBD will notify the operator of the malfunction and will log the event 

electronically. This electronic record is available after the event. 

• Volvo Penta starts and runs each engine at the factory as a final quality control step. It 

can maintain OBD data for a reasonable period of time on each engine to prove 

compliance at the factory. 

• PLT testing for SD/I is economically burdensome for no added benefit because 

information it provides is duplicative of the data collected in the OBD system. The 

capital investment cost to add the PLT equipment to Volvo Penta’s production facility is 

over $CBI. This capital investment adds an annual financial burden of $__CBI____to 

$__CBI_____ for in- plant testing that will translate directly into increased costs for the 

consumers. In addition, the time to install the necessary equipment in the plant is 

approximately 18-24 months. This means that it is highly unlikely that Volvo Penta 

would be able to comply with a mandatory PLT rule unless the implementation is pushed 

back until 2 years after the final rule takes effect. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

• Finally, Volvo Penta asks that the EPA be required to supply justification for this 

requirement especially after EPA staff concurred in a public forum that if OBD was 

added to the rule. 

Pleasurecraft Marine commented in a hearing that Section 1045.301 outlines the method 

for testing production line engines. Pleasurecraft would like to see the elimination of this 

requirement since the On Board Diagnostic system will detect any malfunctions or abnormalities 

and will prevent the engine from being introduced into commerce until proper corrections are 

implemented. Additionally this process will harmonize with CARB procedures. 

NMMA submitted information from Pleasurecraft Marine to support their position that 

PLT is not required. Currently, every engine at Pleasurecraft Marine is 100% tested and 

validated on engine run cells at the end of the production line. This validation process consists of 

starting and running every engine, and allowing the engine to cycle through the warm-up and 

come to complete operating temperature. The engine is then run up to an elevated RPM to insure 

that ALL computer-sensed comprehensive component diagnostics are run and pass. Every engine 

is checked and monitored for any type of leaks, including exhaust. Fuel pressure of every system 

is validated. Pleasurecraft Marine uses a bar code system that insures that the correct calibration 

is being downloaded into each engine. A manual validation is also recorded using the ECM 

checksum number. During the run cycle, engine data is recorded and filed according to engine 

serial number and build date to insure that every engine that gets released from production has 

valid, passing data on the emission control system. Serial numbers are associated with GM “hot 

stamp” numbers in the event of any service bulletins and/or recalls from PCM and/or any vendor, 

the engines can be fully tracked. 

With the addition of OBDM, Pleasurecraft Marine’s control and diagnostic systems 

follow the same logic as the automotive industry’s OBDII. They now have closed-loop fuel 

control, misfire diagnostics and catalyst monitoring. Every engine with OBDM will go through a 

run cycle at the end of the production line the same as we currently do. In addition, all emissionrelated diagnostics are being run 100% to validate the integrity of the catalyst system. Further to 

that, these engines are always running an “end-of-line” test for us in the field, hence the 

development of OBDM. 

With the fact that the industry has worked so diligently toward a common system that 

meets the requirements of reducing emissions, and constantly monitors that system for any fault 

or deterioration; Pleasurecraft Marine and NMMA believe that production line testing imposes a 

significant burden with little or no additional benefit. 

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Letters: 

Commenter Document # 

NMMA 0688 

Indmar 0667 

Mercury 0693 

Pleasurecraft Marine (hearing) 0642 

Volvo 0708 

NMMA/Pleasurecraft Marine 0748 

Our Response: 

 We are skeptical that diagnostic systems alone are adequate for confirming that 

production engines routinely meet emission standards. Diagnostic systems are designed to detect 

defects and are not effective tools for quantifying the emission effects resulting from production 

variability from properly functioning engines. However, there are several factors that lead us to 

conclude that we should not require production-line testing for SD/I engines in this rulemaking. 

First, California has not yet adopted production-line testing requirements for these engines. 

Second, the companies producing these engines are predominantly small businesses. Third, the 

relatively short useful life and small sales volumes limit the overall emissions effect from these 

engines. Fourth, we are aware that marine engines may need additional setup time for testing to 

simulate the marine configuration. We do not consider any of these issues to be fundamental, 

but we believe it is best to defer consideration of a requirement for production-line testing until a 

later rulemaking. This would allow us to better understand the degree of compliance with 

emission standards, the effectiveness of diagnostic controls, and California’s interest in requiring 

production-line testing. Note that we may continue to use selective enforcement auditing to 

evaluate the performance of production engines if we have reason to believe that this testing is 

necessary. 

3.10.2 Other PLT issues for OB/PWC engines 

This section includes additional comments related to production-line testing for Marine 

SI engines. See Section 1.3 for further discussion of broader issues related to production-line 

testing. 

What Commenters Said: 

Honda commented that in the interest of potentially reducing the testing burden, we 

suggest that a manufacturer be allowed the alternative of ramp modal testing for PLT even if the 

engine has been certified using the modal test. 

Referring to Section 1045.301(e) in the proposal, Honda supports the option of reduced 

PLT but they suggest it should not be limited to carryover engines nor require two years of test 

results for qualification. PLT is intended to validate both factory production methodology and 

control (production in many cases of more than one engine family) and the production of the 

subject engine family. When introducing a new engine or engine family a factory with a history 

of producing engines that pass production line testing should be allowed to qualify an engine 

family for reduced testing after one quarter of passing tests. Further, the reduced testing rate 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

should not be one per year as written in the proposal but zero until an emission related change is 

made to the engine family. 

ECO commented that EPA should allow small-volume engine manufacturers to utilize 

the use of alternative testing methods (portable emissions analyzers) to demonstrate in-use field 

testing compliance for production units. 

Letters: 

Commenter Document # 

Honda 0705 

ECO 0712 

Our Response: 

We consider ramped-modal testing and discrete-mode testing to be equivalent for a given 

duty cycle. Manufacturers may perform either type of cycle for certification. However, to 

ensure consistency, manufacturers must use the same method used for certification for any 

production-line testing or in-use testing. Similarly, any EPA testing would be based on the same 

type of cycle the manufacturer used for certification for that engine family. If manufacturers 

would certify based on discrete-mode testing and would want to do ramped-modal testing for 

production-line engines, they would need to submit test results from ramped-modal procedures 

as part of a revised application for certification. 

Production-line testing with the CumSum statistical procedures to establish sampling 

rates involves relatively low levels of testing to establish that engine family meets emission 

standards taking into account the variability associated with production tolerances and other 

assembly variables. After new emission standards take effect is an especially important time for 

testing to confirm that engines are meeting emission standards. We believe two years of testing 

with a given engine family is necessary to gain enough confidence to reduce the testing rate to a 

token level. Test results demonstrating compliance with previous standards or test results from 

different engine families do not provide a sufficient assurance that the production variability of a 

given engine family is adequately understood and controlled to demonstrate that production 

engines will uniformly comply with emission standards. This is especially important for engine 

families that generate or use emission credits, since manufacturers should take production 

variability into account when they establish a family emission limit. 

We note that we would make an exception for outboard or personal watercraft engines 

certified with a family emission limit under the current standards if manufacturers certify the 

same engine model under the new standards using the same family emission limit. In this case, 

we could consider two years of data showing consistent compliance with emission standards to 

establish a lower testing rate for further production, even if that testing occurred before the 

effective date of the new emission standards. 

It is important to continue testing at least one engine from each engine family even after 

we agree that less testing is required. Manufacturers often make minor changes over time that 

should be reflected in ongoing measurement, if only occasionally. For example, manufacturers 

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may make several running changes to their certified configuration over time based on 

engineering developments, changed suppliers of emission-related components, updated assembly 

procedures, or simply turnover in production workers. We believe it is reasonable for 

manufacturers to test one engine per year as a minimal step to confirm that the engines being 

produced continue to meet emission standards. We would want to be able to require 

manufacturers to restart the normal regimen for production-line testing if a problem arises. We 

would have no easy way of making this determination if manufacturers would completely 

discontinue testing of production engines. 

We agree that the regulations should allow for simpler measurement methods for 

production-line testing, as described in Section 1.3.4. 

3.11 In-use testing 

3.11.1 In-use testing for SD/I engines 

What Commenters Said: 

NMMA and Mercury Marine commented that EPA proposes to exempt SD/I engines 

from in- use testing in the proposed rule in § 1045.401(a). NMMA agrees with EPA that in- use 

testing is not feasible for SD/I engine manufacturers given that SD/I engines are installed in 

vessels and these engines would need to be removed for laboratory testing. Such testing would 

practically destroy the vessel—a consequence that boat owners would want to prevent. 

NMMA and Mercury continued that EPA also asks for comments on other approaches 

that could be used for accumulating operating hours with SD/I engines to make in- use testing 

possible. 72 Fed. Reg. at 28,124. EPA’s suggestion that SD/I engine manufacturers could 

perform in-use tests on boats maintained for research and development or for company use is 

impractical and contrary to the intended purposes of these boats. Boats used for research and 

development may not represent the configurations that are actually in the field or they may not 

have a representative service accumulation. As for company fleets used for recreation, such 

fleets also would not likely include all of a company’s products and/or the vessels may not have 

sufficient in-use service accumulation. Another important consideration is that OBD systems will 

be installed with SD/I engines. The OBD system will notify the owner and operator of any 

problems with the emission control system and parts that need to be repaired. For these reasons, 

EPA’s determination that SD/I engines be exempt from in- use testing requirements makes sense. 

NESCAUM commented that it is essential that the engines affected by this rulemaking 

meet the applicable standards for the entire useful life of the equipment into which they are 

installed. Consequently, they contend that the proposed requirements for verifying durability of 

emissions controls, as they pertain to SD/I engines and [vessels], are inadequate, principally 

because there are no requirements for in-use emissions testing. ... Consistent with the durability 

requirements pertaining to OB/PWC engines, they urge EPA to incorporate similar requirements 

for manufacturers of land-based SI and SD/I engines and equipment, including a robust in-use 

testing program. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

NESCAUM 0641 

Mercury 0693 

Our Response: 

The industry comments generally reinforce the reasons we gave in the proposal to 

suggest that in-use testing would not be appropriate for SD/I engines. We believe the best 

approach for ensuring proper in-use control is to explore the viability of collecting data from 

installed marine engines using portable analyzers. The requirements related to torque 

broadcasting and access ports in exhaust systems make this possible. This will be especially 

relevant for evaluating compliance with Not-to-Exceed standards. Rather than requiring 

manufacturers to perform this testing after accumulating some specified degree of service hours, 

we intend to perform our own testing as needed to gain experience with the measurement 

technology and sampling and testing protocols. 

3.11.2 In-use testing for OB/PWC engines 

What Commenters Said: 

NMMA commented for OB and PWC engines, EPA is proposing to continue to require 

in-use testing of field-aged engines to determine whether they continue to meet the emissions 

standards. 72 Fed. Reg. at 28,134. Proposed subpart E contains the provisions related to the 

manufacturer-run in-use testing program. PWC and OB engine manufacturers have had to 

comply with in-use testing requirements for almost a decade. What NMMA members have seen 

over the years is that the in- use program is a highly resource intensive program with very little, 

if any, environmental benefit. The costs to manufacturers for locating and obtaining the engines, 

extracting the engines in the case of PWCs (sometimes practically destroying the product), and 

dedicating personnel to conducting the tests are significant. Also adding to the cost of these tests 

has been the lack of adequate notification to manufacturers of the particular engines that must be 

tested. In some cases, in-use test orders have been received by manufacturers after the start of the 

following model year, which has significantly increased the burden on manufacturers to obtain 

engines and conduct testing in a timely manner. With all of these costs, NMMA members have 

not seen a single engine family fail the in-use test requirements in the past ten years. From a 

cost-benefit perspective, therefore, there is no justification for retaining the in-use testing 

program for PWC and OB engines in this new rule. Any concerns about backsliding with the 

removal of this program from final rule are unfounded given that other enforcement programs, 

e.g., EPA’s Selective Enforcement Audit Program, will ensure continued compliance with the 

emissions standards. NMMA fails to see how the continued application of the in- use program to 

PWC and OB engine manufacturers is justified from a cost-benefit perspective. 

NMMA continued to comment that the in- use testing program was included in the final 

1996 rule for PWC and OB engines in order to “provide information regarding the in- use 

emission performance of engines in relation to the expected in- use performance to which the 

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Chapter 3: Marine SI Engines 

engines were designed and built.” See Control of Air Pollution; Final Rule for New Gasoline 

Spark Ignition Marine Engines; Exemptions for New Nonroad Compression Ignition Engines at 

or Above 37 Kilowatts and New Nonroad Spark Ignition Engines at or Below 19 Kilowatts, 

Final Rule, 61 Fed. Reg. 52,087, 52,094 (Oct. 4, 1996). EPA also explained that such a program 

was “advantageous because it is an innovative method of gaining acceptable knowledge of inuse engine emission performance.” Id. With the experiences gained in implementing this 

program and the lack of any engine family failure, the in-use program has served its intended 

purpose. Continuing a regulatory program merely for the sake of the program is poor policy and 

ignores the considerable costs and resource burden associated with the in- use testing program. 

NMMA commented that another important consideration is that the requirement to install 

an OBD system as specified in § 1045.110 will ensure that an owner is notified in the field of 

any problems with the emission control system. For all these reasons, NMMA believes the best 

approach is to amend § 1045.401(a) to include the following provision: “Engines equipped with 

an on-board diagnostic system meeting the requirements in § 1045.110 of this subpart are 

exempt from the requirements of this section.” 

NMMA continued that if EPA elects to retain the in- use testing program, despite the lack 

of any environmental benefit and the considerable costs, there are several revisions to §1045.405 

that must be included in the final rule. While NMMA appreciates EPA’s efforts to set out a 

schedule in § 1045.405(b)(1) for EPA to notify the manufacturer as to which engine families 

must be tested, the proposed text of § 1045.405(b)(2) is burdensome and requires revision. To 

that end, NMMA recommends several changes to proposed § 1045.405(b)(2) to ensure that 

manufacturers are not penalized for certification applications that are received after December 31 

of a given calendar year for engines that are early production models. NMMA also suggests that 

the in- use testing burden be reduced for carryover engines and for engines that have not 

experienced any in-use testing failures for the past two years. The recommended revisions are 

included below in redline. 

§ 1045.405 How does this program work? 

* * * * 

(b) The provisions of this paragraph (b) describe how test families are selected, depending on when we receive 

the application for certification. 

(1) If we receive the application or a letter of intent with a list of all engine families you will be certifying and 

the estimated dates of production by December 31 of a given calendar year for the following model year (for 

example, by December 31, 2009 for model year 2010), we would expect to select engine families for testing 

by February 28 of the model year. If we have not completed the selection of engine families by February 28, 

you may select your own engine families for in- use testing. In this case, you must make your selections and 

notify us which engine families you have selected by March 31. You should consider the following factors in 

selecting engine families, in priority order: 

(i) Select an engine family that has not recently been tested in an in-use testing regimen (and passed) under the 

provisions of this subpart. This should generally involve engine families that have not been selected in the 

previous two model years. If design changes have required new testing for certification, we would consider 

that this engine family has not been selected for in-use testing. 

(ii) Select an engine family if we have approved an alternative approach to establishing a deterioration factor 

under § 1045.245(b)(7). 

(iii) Select the engine family with the highest projected U.S.-directed production volume. 

(2) If we receive an application for a given model year after December 31 of the previous calendar year, you 

must conduct in-use testing with that engine family without regard to the limitations specified in paragraph (a) 

of this section, unless the engine family is a carryover or we waive this requirement. We will generally waive 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

testing under this paragraph (b)(2) only for small volume engine manufacturers or in the case where similar 

testing was recently completed for a related engine family or the engine family has not failed an in- use test in 

the past two years. 

In addition to these revisions, NMMA recommends that EPA reduce the annual quantity of 

engine families required for testing to two engine families per year given the compliance history 

of these engines. These changes will help reduce the burden of the in-use testing program for OB 

and PWC engine manufacturers while meeting the basic objectives of that program. Lastly, 

NMMA recommends adding a new paragraph (e) to § 1045.405 as follows: 

(e) In appropriate extreme and unusual circumstances that are clearly outside the control of the 

manufacturer and could not have been avoided by the exercise of prudence, diligence, and due care, we 

may waive the in-use testing requirement for an engine family. 

Suzuki commented that unlike similar programs conducted with on-highway vehicles, 

outboard engines used for in-use testing are not procured from privately owned sources for a 

variety of reasons, and are basically engines operated for the sole purpose of service 

accumulation needed for compliance with the in-use testing program. This testing is extremely 

resource intensive, and requires the sacrifice of numerous expensive outboard engines each year. 

Additionally, because the engines used for in-use testing are operated solely for the purpose of 

engine age accumulation for the EPA program, literally hundreds of hours of engine operation 

occur for each engine test group selected for in-use testing for the single purpose of service 

accumulation for in-use testing. 

Suzuki continued to comment that it is arguable that this program had merit in the initial 

years of outboard engine certification, during which time new technologies were being 

introduced to replace long established technologies and EPA needed to ensure that proper 

emissions system durability existed for this then-newly regulated engine category. What has 

been demonstrated in the years since that time is that the outboard engine industry is building a 

very robust product. As evidence, Suzuki is not aware of a single case of failure of an outboard 

engine family selected for in-use testing from any manufacturer. 

Considering this exemplary performance from the entire industry, Suzuki does not 

believe continuation of the in-use testing program for outboard engines can be justified at this 

time. Suzuki requests that the program be suspended until such time that EPA can demonstrate a 

compelling need to reinstate the program. 

BRP has been subject to the in-use testing requirements of 40 CFR Part 90 since their 

inception. The EPA proposal maintains the current in-use requirements and provides some relief 

from the in-use order timing issues BRP and other manufacturers have experienced. While BRP 

appreciates EPA's efforts to streamline the implementation of this program, it is a program which 

as outlived its usefulness. To date, BRP has not had a single engine family fail this in-use 

program. This program costs BRP approximately $200,000 US dollars annually, and does not 

provide any emission reduction or benefit to the environment. 

BRP is requesting EPA to remove the in-use program from the proposed regulation. 

Alternatively, BRP request to have in-use testing apply only to engine families which have failed 

the production line testing requirements. 

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Chapter 3: Marine SI Engines 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Mercury 0693 

Suzuki 0698 

Our Response: 

In-use testing can provide very valuable information to confirm that engines are 

complying with emission standards after many hours of operation under in-use conditions. We 

believe this is especially relevant in the context of Not-to-Exceed standards. Manufacturers may 

also choose to do their in-use testing with portable analyzers with engines that remain installed 

on a vessel. This would be the best way of characterizing the effectiveness of an engine’s 

emission controls. This would also allow for nondestructive testing with personal watercraft 

engines. We understand there have been very low failure rates on OB/PWC engine families 

previously selected for in-use testing, nevertheless, there remains a need for on-going oversight. 

We do not believe that the beginning of a new emissions program is a good time to reduce 

oversight. We will continue to monitor results and may adjust testing rates as appropriate if the 

results consistently meet the standards. 

At the same time, we understand the concerns related to the burden of service 

accumulation with in-use engines and repeat measurements within an engine model in successive 

years. While we believe the specified sampling rate of 25 percent of engine families is 

appropriate to ensure that we can adequately cover the range of engine families that should be 

tested, we do not intend to require in-use testing for any engines that have already demonstrated 

compliance under an in-use testing program. This would apply if an engine family’s certification 

is based on carryover of emission data from an earlier engine family for which in-use testing 

results were adequate to establish compliance with emission standards. We would nevertheless 

be able to select such an engine family for testing if we had a reason to believe that this testing 

was necessary, such as a changed family emission limit, increased variability from testing with 

production-line engines, or reported emission-related defects. 

As noted in the proposal, we are committing to a schedule for selecting engine families in 

time for manufacturers to be able to establish a fleet for in-use testing. The proposed approach 

depends on holding manufacturers responsible for products they produce after the scheduled time 

for selecting engine families. Also as noted in the proposal, if manufacturers do not want to be 

subject to automatic in-use testing obligations, they can simply assign the engine family to the 

following model year. This would then put that engine family into the pool of available families 

for us to select for the upcoming model year. It is not necessary to specify that carryover engines 

are exempt from this scheduling requirement, since we will generally not be selecting carryover 

engine families for testing if they have already passed under the in-use testing program, as 

described above. If such an engine family were not yet tested, or it were tested without passing, 

we would not want to exempt it from the provisions related to timely certification with respect to 

in-use testing requirements. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

There is no requirement to use diagnostic systems for outboard or personal watercraft 

engines, so it would not be appropriate for us to tie in-use testing requirements to such a system. 

Moreover, diagnostic systems are intended to find defects and are not effective at evaluating the 

emission levels relative to an emission standard (or a family emission limit). 

We agree with the manufacturers’ suggestion that the regulations should include “force 

majeure” provisions that would allow for revising the plan for performing in-use testing if 

circumstances outside manufacturers’ control prevent them from completing the necessary 

service accumulation. 

3.12 Compliance provisions 

3.12.1 Competition exemption 

What Commenters Said: 

Mercury Marine and NMMA commented that Mercury Racing manufactures engines, 

both for the recreational market and for competition racing. In some cases, engines used in 

competitive events are the same as the recreational engines and would be certified engines. 

However, Mercury Racing also produces engines that are strictly for racing and would be 

inappropriate for recreational use. 

Mercury and NMMA continued to comment that in addition to the exemptions provided 

in 40 C.F.R. Part 1068, EPA is proposing to include an exemption for engines used for 

competition similar to other off-road programs. To qualify for the proposed exemption in § 

1045.620, a Marine SI engine would have to meet all four criteria, which include restricted 

display, sales and use as well as superior performance characteristics. While several of these 

criteria are similar to those required for other programs, such as the competition exemption in 40 

C.F.R. § 1051.620 exemption for snowmobiles and ATVs, there are several differences which 

are problematic and need to be resolved before EPA finalizes this provision. Namely, the first 

criterion in § 1045.620(c)(1) requires that “neither the engine nor any vessels containing the 

engine may be displayed for sale in public dealerships or otherwise offered for sale to the general 

public.” 72 Fed. Reg. at 28,282 (proposed § 1045.620(c)(1)) (emphasis added). The italicized 

language is not only additional to what is required for other programs but it also would make 

boat show displays of the racing engine or vessel impossible. The public dealership restriction 

also is not workable with this industry as it is common practice for a dealership to sponsor a 

racing team and display the boat used for competition on the sales floor. This type of display is 

not intended as a sale of the vessel and instead is a promotional effort to sell other boats, 

however, CARB’s interpretation is that if a boat is displayed at a dealership or boat show, it is 

deemed to be “For Sale” unless it is clearly labeled as not being for sale. Mercury Marine 

recommends that the first criterion be eliminated. 

The third criterion, which requires that the engine have performance characteristics that 

are substantially superior to noncompetitive models also is a concern. There are some engines in 

a competition class that may not have performance characteristics that are “superior.” For 

example, some racing classes of engines have engine displacement or horsepower restrictions to 

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Chapter 3: Marine SI Engines 

equalize the field. Mercury Marine suggests that this criterion be revised as set forth in the 

redline below. 

In addition, the requirement in proposed § 1045.620(c)(4) and (e) regarding the restricted 

use of the competition engines places an undue burden on Marine SI engine manufacturers. 

There is no such restriction included in the competition exemption for other programs. While 

manufacturers of marine engines may have control over whether the competition engines are 

sold to racing teams and other qualified racers, once the sale occurs to the appropriate entity, the 

manufacturer has no way of restricting the use of the engine. To address this situation, Mercury 

Marine recommends that EPA delete § 1045.620(c)(4) and rephrase (e) so that the types of 

events listed are provided as examples. 

The following redline of § 1045.620 is provided to illustrate our recommended revisions 

to the section: 

§ 1045.620 What are the provisions for exempting engines used solely 

for competition? 

The provisions of this section apply for new engines and vessels built on 

or after January 1, 2009. 

(a) We may grant you an exemption from the standards and requirements

of this part for a new engine on the grounds that it is to be used solely for 

competition. The requirements of this part, other than those in this 

section, do not apply to engines that we exempt for use solely for 

competition.

30 

(b) We will exempt engines that we determine will be used solely for 

competition. The basis of our determination is described in paragraphs (c) 

and (d) of this section. Exemptions granted under this section are good for 

only one model year and you must request renewal for each subsequent

model year. We will not approve your renewal request if we determine 

the engine will not be used solely for competition.

(c) Engines meeting all the following criteria are considered to be used

solely for competition:

(2) Sale of the vessel in which the engine is installed must be limited to

professional racers or other qualified racers. 

(3) The engine must have characteristics that are substantially different

from noncompetitive models rendering them unsuitable for recreational 

use, e.g., a transmission that cannot be engaged/disengaged while the 

engine is running.

(d) You may ask us to approve an exemption for engines not meeting the 

criteria listed in paragraph (c) of this section as long as you have clear and 

convincing evidence that the engines will be used solely for competition.

(e) Engines are considered to be used solely for competition if their use is 

limited to competition events sanctioned by the U.S. Coast Guard or

another public organization. Operation of such engines may include racing 

events, speed record attempts, official time trials and test/trial runs in

preparation for racing events. Use of exempt engines in any recreational 

events, such as poker runs and lobster boat races, is a violation by the boat

owner of 40 CFR 1068.101(b)(4). 

(f) You must permanently label engines exempted under this section to

clearly indicate that they are to be used only for competition. Failure to

properly label an engine will void the exemption for that engine. 

(g) If we request it, you must provide us any information we need to

determine whether the engines are used solely for competition. This would 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

include documentation regarding the number of engines and the ultimate

purchaser of each engine as well as any documentation showing a vessel

manufacturer’s request for an exempted engine. Keep these records for 

five years. 

Mercury stated that these recommended changes will ensure that the competition 

exemption achieves its intended purpose while reflecting how these engines are distinct from 

conventional Marine SI engines and how they are actually marketed. Mercury supplied the 

issues they have with the Competition Use Exemption 1045.620. They stated that they do not 

think anything they are suggesting changes the intent, they just do not want to see enforcement 

actions taken due to wording. 

(c) In the meeting, Alan Stout said that companies needed to meet one or more of the 

criteria. This says they must meet all of the criteria. 

(1) These boats are often displayed at dealerships. While they are not for sale to the public, 

dealers may not be aware that they would have to make it clear on the display that they are 

not for sale. Mercury feels it should say that they can be displayed, but not sold to, the 

general public. 

(2) OK 

(3) Many classes of racing limit engine size or Hp so this statement may not always be true. 

A statement that these engines "may have characteristics the are different from noncompetitive engines" would be more accurate. Some have very short gearcases (OB), some 

are start in gear (no neutral), some require leaded fuel, etc. Also, some are standard old 2-

strokes that certain racing classes standardized on (APBA has a class that can only run 

Mercury 25 Hp 2-strokes on very small hydroplane boats.) 

(e) Use should also include practice for a sanctioned racing event. 

Mercury concluded that everything else is OK. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

Mercury 

Our Response: 

The commenters object to the proposed provision disallowing competition models from 

being “displayed for sale” on the basis that the competition models are displayed merely to 

promote noncompetition models. However, the proposed provision clearly would prohibit 

displaying competition models “for sale” while not prohibiting their display for other purposes, 

such as promoting noncompetition models. This clarification should be sufficient to address the 

commenters’ concerns. Furthermore, our regulation has no bearing on California’s enforcement 

of their own regulations. We believe there is no need to change the provision in question. In 

fact, making the recommended change would amount to permission to display the engines for 

sale to the general public, which would completely undermine any assurance that the exemption 

would not be abused. 

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Chapter 3: Marine SI Engines 

We contemplated the situation in which engines would be used only for competition 

without meeting all the criteria proposed under §1045.620(c). To address this possibility, we 

proposed §1045.620(d), which allows us to approve an exemption in cases where the 

manufacturer can provide clear and convincing evidence that an engine will be used solely for 

competition. We believe this provision addresses the commenters’ concerns and that the 

proposed regulations do not need to be changed. 

We believe it is entirely appropriate for the regulations to prohibit the use of exempted 

competition engines for noncompetition purposes. This has been identified in §1068.101 as a 

prohibited act since 2002. We have referenced this prohibition in §1039.620 for nonroad diesel 

engines and in §1048.630 for Large SI engines. Furthermore, aside from Marine SI engines, we 

have proposed language referencing this prohibition in §1054.620 for Small SI engines and in 

§1045.620 for marine diesel engines. We believe the specific language in the regulation is 

appropriate for delineating the type of operation that we would consider appropriate for 

exempted engines. We have stated that operation of competitive engines may include only 

racing events, trials to qualify for racing events, and practice associated with racing events in 

§1045.620(e) as a clarification of what is considered to be competition, rather than as an 

additional prohibition. Finally, we believe that Mercury’s concern results from a mistaken 

interpretation of §1045.620(e) that we would void the exemption for the engine manufacturer 

based on the inappropriate use of the engine for which the manufacturer was not reasonably 

responsible. These clarifications should be sufficient to address the commenters’ concerns. We 

believe there is no need to change the provision in question. 

3.12.2 Personal use exemption 

What Commenters Said: 

N. Leggett (0603) commented that the proposed rules allow individuals to build vessels 

for their own personal use without regulation. This is a wise idea that supports the American 

tradition of do-it-yourself and it allows inventors and other creative technologists to build vessels 

that are totally their own design. However, part (c) “No individual may manufacture more than 

one vessel in any ten-year period under this exemption” has a major problem. If a person is 

building small vessels, he or she will probably be interested in building more than one vehicle in 

a ten year period. The commenter built a small (one-man) hovercraft and the project certainly did 

not keep him busy for 10 years. However, if a person is building a large yacht, he or she will 

probably build only one yacht in ten years. The commenter stated that we need an exemption that 

is related to the size of the boat being built. A person who is building little runabouts should be 

allowed to build several of them in ten years. A person building a very large boat will probably 

not be inhibited by a one boat in ten year limit. At least three size thresholds are needed to make 

this exemption realistically meet the needs of individuals building vessels for their own personal 

use. 

N. Leggett (0612) commented that individuals who build boats for their own personal use 

should be allowed to build up to three small boats (under 20 feet overall length), or two medium 

size boats (under 35 feet overall length) or one larger boat in a 10-year period. These boats 

would be exempted from the regulations. This is a change from the proposed limit of one boat in 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

a 10-year period. People building a mix of smaller and larger boats would be limited to a total of 

two boats. This exemption would apply to hovercraft, hydrofoils, and airboats as well as to 

conventional boats. 

Letters: 

Commenter Document # 

N. Leggett 0603 

N. Leggett 0612 

Our Response: 

We intended the personal-use exemption more to allow someone to build a boat for his 

own personal use rather than creating a path for hobbyists to continuously produce new 

homemade vessels. On the other hand, we believe it is appropriate to consider that five years 

(rather than the proposed ten years) is an appropriate period for expecting someone to use a 

homemade boat. Circumstances might change over that time such that a different size or type of 

vessel would meet an individual’s needs. We are therefore changing the proposed regulation to 

specify that a person may make one exempt vessel over any five-year period. We believe this is 

preferable to allowing some number of vessels to avoid creating an expectation or an allowance 

for continuous production of homemade vessels. The five-year period aligns with the proposed 

restriction against selling an exempted vessel for five years after construction. Any more 

frequent construction would only put a personal boat builder in a position of owning multiple 

boats at one time for his personal use. We believe it is not necessary to accommodate this 

concern. 

3.12.3 Allowance to use Small SI engines 

What Commenters Said: 

Ingenium commented that they are writing in response to the April 17, 2007 

announcement by the EPA to create new legislation that would regulate emissions from Inboard 

marine engines. The proposed regulations propose to place particularly stringent emissions 

controls on Stern Drive and Inboard engines, more stringent than either outboard engines or 

personal watercraft engines. This appears to be a decision made because the preponderance of 

Stern Drive and Inboard engines are automotive based and so those engines can benefit from a 

vast array of emissions technology developed in the automotive world. In addition, the large 

marine manufacturers like Mercury Marine and others, have the R&D and other financial 

resources to develop other emissions capabilities such as water cooled three way catalysts, on 

their own. Since they produce the vast majority of marine specific engines and they are 

manufacturers. 

Ingenium continued to comment that it appears, based on the second paragraph of page 

42 of 40 CFR that the EPA recognizes that there may be smaller Inboard engines in use that EPA 

is not currently aware of and EPA makes the assumption that these smaller engines would have 

similar emissions control capabilities as their larger Inboard counterparts. The EPA also 

"requests comment on the need for adjusting these proposed standards to accommodate any 

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Chapter 3: Marine SI Engines 

technical constraints related to their unique designs." So they are writing in response to this 

request for comment. 

Ingenium Product Development, Inc. has spent the last three years developing a new type 

of marine propulsion system for very small boats that uses V-twin air cooled engines from the 

lawn and garden industry to propel the boat. Their product can be seen at: http://www.ventboats.com. At the current time their plans are to use engines between about 10 hp and 36 hp 

which are manufactured by Briggs and Stratton and other companies. They are air cooled, 

carbureted four-cycle engines. These engines are very low in cost and so they hope to be able to 

reduce the cost of the final product to the consumer. To their knowledge they are the only 

manufacturer in the USA that is using these types of engines in an inboard configuration. There 

are some other manufacturers like Mudbuddy using these same engines in an Outboard 

configuration. The volumes they anticipate are always going to be low, perhaps 1,500 - 2,500 per 

year after five more years of growth. So they are a miniscule contribution to the world's 

emissions problem. 

Ingenium commented that these engines are not on the same developmental timeline as 

automobile engines as far as emissions. In fact the small engine regulations that are being 

proposed for the lawn and garden industry lag behind the marine standards by several years. 

Large manufacturers of air cooled L&G engines produce millions of these engines per year. 

There is simply no way they will modify our tiny fraction of engines that are used for the marine 

markets to accommodate special emissions capabilities. Put another way if they cannot use these 

engines as they are they will have to go out of business. Ingenium sees that EPA has some type 

of waiver language in the proposal if the total number of engines used from other industries is 

less than 5% of a manufacturer’s total. They would fall under that comfortably because again, 

Briggs and Stratton makes millions of these engines for their primary intended market, riding 

lawnmowers. 

Ingenium commented that it seems that they need some type of waiver or allowance to 

use these engines or maybe the proposal already covers their situation and they just cannot find 

it. At this time they are requesting that EPA respectfully consider their request for special 

allowance to use 4-cycle carbureted engines from the Lawn and Garden engine manufacturers, in 

a limited volume marine application, with the emissions controls that are in place on the engine 

as purchased from the manufacturer. 

ARB does not support using certified small spark-ignition engines in marine applications 

without certifying to the marine spark-ignition emission standards. ARB’s recreational marine 

engine programs have additional important requirements such as consumer “Star” labels, 

different useful life periods, and issues specific to use in a marine environment. As an 

alternative, ARB recommends that carry-over of certification data and DFs should be allowed 

where appropriate, thereby reducing the certification burden. 

Honda has concerns with the proposal for extraordinary labeling and reporting for one 

specific application of general purpose engines. In §1045.605(d)(5), small volume products that 

use these engines, such as mud/swamp boats, have been singled out for the addition of a 

supplemental label. While the engines will have small engine emission labels confirming 

regulatory compliance, the Proposal has clearly carved a niche for these unique engine 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

applications. This requirement will inherently present added burden to the very small business 

entities producing these products and we do not understand its purpose or benefit expected from 

it. 

EMA commented that engine manufacturers do not have the ability to control their 

customer’s novel use of engines that are designed and intended for utility (i.e., a wide variety of 

product) applications. To the extent that the engines involved are not marinized, EPA should not 

differentiate utility engines from any other product application. Engines that are either Small SI 

or certified to the Small SI requirements defined in 40 CFR Part 1054/1060 by provisions 

allowed in 40 CFR Part 1048 should not be required to be certified to the Marine SI emission 

standards found in 40 CFR Part 1045. If such engines are required to be tested under the Part 

1045 procedures, the benefits associated with not having to certify to Part 1045 would be 

eliminated. 

EMA continued to state that the provisions of §91.1013 EXEMPTION FOR CERTIFIED 

SMALL SI ENGINES allow manufacturers to use marine engines that have been certified to 

emission standards for non-road spark-ignition engines below 19 kW without recertifying those 

engines under part 91. This proposed language should be revised in a fashion similar to 

§1045.605. Specifically, this section also should include references to engines certified to either 

40 CFR Part 90 or 40 CFR Part 1054 in order to avoid confusion and ensure that engines <=1000 

cc displacement and <=30 kW certified to either 40 CFR 90 or 40 CFR Part 1054 are acceptable. 

EMA commented that this section (§91.1013) also includes a reference to §1045.605, 

which requires SORE engines used as marine propulsion engines to comply with special labeling 

and record keeping requirements. The requirements specified in §1045.605(d)(2), and (5) - (7) 

only should be applicable to vessel manufacturers. The engine manufacturer does not have the 

ability to ensure that these requirements are fulfilled. To satisfy the requirements of 

§1045.605(d)(3), the engine manufacturer should only be required to submit a statement of 

compliance that indicates that the majority of the applicable engine family’s sales are not used 

for marine propulsion. 

Marine propulsion engines are generally regulated per 40 CFR Part 91 and 1045 as 

identified. However, per §1045.605 engines that are certified to the requirements of 40 CFR Part 

1054 are also considered valid without separate application for certification under Part 1045. We 

recommend that the language of §1054.5(c) “Which nonroad engines are excluded from this 

part’s requirements?” be revised to read: (c) Propulsion marine engines. See 40 CFR parts 91 and 

1045. Note that engines certified for compliance with Part 1054 may be utilized for marine 

propulsion as described in §1045.605. Note that the evaporative emission standards.....” 

Letters: 

Commenter Document # 

Ingenium 0616 

CARB 0682 

Honda 0705 

EMA 0691 

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Chapter 3: Marine SI Engines 

Our Response: 

We appreciate the informative comment from Ingenium, pointing out that there are very 

small inboard engines that are not based on automotive technology. We believe it is appropriate 

to expand the provision for using engines certified to Small SI standards to sterndrive and 

inboard engines rather than limiting this to outboard and personal watercraft engines. This is 

appropriate for Small SI engines certified under the Phase 2 standards in part 90 or the Phase 3 

standards in part 1054. 

We believe the allowance to use marine engines that have been certified to standards for 

land-based products is an important provision to address concerns for small businesses and for 

niche products. By limiting the numbers of these cross-certified engines to a small fraction of 

their total sales, we are able to address these concerns without undermining the marine 

regulations in which we have developed a unique set of requirements with respect to engine 

operation, useful life, engine maintenance, and other important parameters. Requiring even a 

streamlined certification, as California ARB suggests, would still pose a burden that we believe 

is not appropriate for small numbers of engines that have already been certified to EPA 

standards. 

We proposed to allow conversion of land-based engines for marine applications under the 

provisions of §1045.605. This applied for engines certified to the Small SI standards only if they 

were used in outboard or personal watercraft applications. The provisions of 1045.605 included 

labeling and reporting requirements to document the changes involved in installing the engine in 

a vessel. However, we are adopting a provision allowing broader use of small numbers of 

certified Small SI engines for marine propulsion (see §1045.610). As long as these engines are 

installed without modification in a vessel, we will accept the Small SI certification, with no 

additional testing required, as valid for the marine installation. This is similar to the approach we 

have taken for constant-speed diesel engines that may be used in land-based or marine auxiliary 

applications (see §1042.610). This simpler approach is appropriate for these engines because 

they are typically “drop-in” models that operate very similar to the way they would for any 

number of land-based applications. The sales volumes are also very small relative to the total 

sales in the engine families, and the marine installation is often performed by the owner of the 

engine. 

The regulations include language in §91.1013 that simply references §1045.610. All the 

provisions in §1045.610, including the changes we make for the final rule, apply automatically 

for engines subject to emission standards under part 91. The final version of §1045.610 will 

include language including engines certified under either the Phase 2 standards in part 90 or the 

Phase 3 standards in part 1054. 

Engines that are certified under part 1054 and eventually used in a marine application 

under the provisions of §1045.610 are still subject to all the requirements and prohibitions that 

apply under part 1054. It is therefore not appropriate to include a reference to §1045.605 or 

§1045.610 in §1054.5 where we describe which engines are excluded from the requirements of 

part 1054. At point of sale, Small SI engines should meet the Small SI exhaust standards, as 

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noted above. However, once the engine is installed in a recreational marine vessel, then the 

vessel is subject to the OB/PWC or SD/I evaporative standards. 

3.12.4 Replacement engines 

What Commenters Said: 

NMMA and Mercury Marine commented that in certain situations SD/I engines must be 

repowered due to problems associated with normal “wear and tear” or damage to the existing 

engine block. For these cases, the marine engine manufacturer would need to be able to replace 

the original engine block with a comparable engine that would allow the boat owner to use many 

of the existing components from the original engine. Since the new engine block is dropped into 

the existing vessel in the exact location, it is imperative that the replacement engine fit into the 

space allotted for the engine block. New engines that will be built to meet the standards proposed 

in this rulemaking will not, in most cases, be able to fit in the space allotted to existing engines. 

For these reasons, NMMA and Mercury support the flexibility provided by the proposed 

revisions to the exemptions in § 1068.240, which address the situations where the engine being 

replaced is not subject to the emissions standards or is subject to less stringent emissions 

standards than those that would apply to a new engine. 72 Fed. Reg. at 28,378. The proposed 

revisions would permit a manufacturer to produce and sell a replacement engine identical in all 

respects to the engine being replaced without violating the prohibited acts in § 1068.101. These 

revisions are necessary to allow marine engine manufacturers to continue to provide customers 

with replacements for existing engines. 

Indmar commented that in certain situations SD/I engines must be replaced due to 

problems associated with normal “wear and tear” or damage to the existing engine block. New 

catalyst equipped engines may not package in the space allotted for non-catalyst equipped 

engines. Also the boat wiring would not match the electronics of the new engines. The 

replacement of engines in old boats as defined in 1068.240 is supported by Indmar. This allows 

us to keep customers who have engine problems with old boats satisfied and still meet the intent 

of clean air. 

Letters: 

Commenter Document # 

NMMA 0688 

Indmar 0667 

Mercury 0693 

Our Response: 

We are adopting the proposed replacement-engine provisions, as supported by the 

comments. Note that we are revising the replacement-engine provisions as described in Section 

1.5. The modified §1068.240 nevertheless continues to address the concerns expressed by the 

commenters. 

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Chapter 3: Marine SI Engines 

3.12.5 Defect reporting 

What Commenters Said: 

NMMA and Mercury Marine commented that EPA is proposing to apply the defect 

reporting requirements in § 1068.501 to marine engines in place of the requirements in 40 C.F.R. 

Part 85, which are currently applicable to only PWC and OB engines. 72 Fed. Reg. at 28,203. 

For the investigation threshold, EPA’s proposal would require 10 percent of total production up 

to a total production of 50,000 engines but never fewer than 50 for any single engine family in 

one model year. 72 Fed. Reg. at 28,203. For production between 50,000 and 550,000 units, the 

investigation threshold would increase at a marginal rate of 4 percent. With regard to defect 

reporting requirements, EPA would require a manufacturer to report all occurrences of the same 

defect in all engine families and all model years that use the same part. Id. EPA proposes that the 

threshold reporting for a defect would be 2 percent of total production for any single engine 

family for production up to 50,000 units, but never fewer than 20 for any single engine family in 

one model year. Id. For production between 50,000 and 550,000 units, the reporting threshold 

would increase at a marginal rate of 1 percent. For all production above 550,000, a threshold of 

6,000 engines would apply. 

NMMA and Mercury commented that the new proposed defect reporting requirements 

would cover defects for emission-related components or systems containing the following 

components: “electronic control units, aftertreatment devices, fuel metering components, EGRsystem components, crankcase- ventilation valves, all components related to charge-air 

compression and cooling, and all sensors associated with any of these components.” 72 Fed. Reg. 

at 28,388 (proposed § 1068.501(a)(1)(i)). Defects related to engines and equipment subject to the 

evaporative emission standards also would be covered, including defects related to fuel tanks, 

fuel caps, and fuel lines and connectors. 72 Fed. Reg. at 28,388 (proposed § 1068.501(a)(1)(ii)). 

NMMA and Mercury commented that EPA’s proposed requirements in § 1068.501 are 

different from the defect reporting requirements that SD/I engine manufacturers will have to 

comply with in California. See CAL. CODE REGS. tit. 13, § 2144 (2007). Given that many of the 

SD/I engine manufacturers are small businesses, NMMA and Mercury recommend that EPA 

allow SD/I engine manufacturers to comply with the California program as a substitute for the 

federal program. The California program requires a manufacturer to file an emission warranty 

information report for each quarter when the cumulative number of unscreened warranty claims 

for a specific emission related component or repair represent at least 1 percent or 25, whichever 

is greater, of the engines of a California-certified test group. Id. By giving SD/I manufacturers 

the option to comply with the California program for defect reporting, EPA would reduce the 

administrative burden that would be imposed on these companies by having to comply with two 

different defect reporting schemes. 

NMMA and Mercury commented for the PWC and OB engine manufacturers, the new 

proposed defect reporting program differs from Part 85 in several respects, both in the 

investigation threshold and the reporting threshold. Part 85 requires a defect report to be filed 

when the manufacturer determines that a specific emission-related defect exists in 25 or more 

engines of the same model year. 40 C.F.R. § 85.1903(a). The current program is well-known 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

across the OB and PWC industry, and NMMA fails to see the utility in changing the existing 

defect reporting requirements that will merely serve to increase the regulatory burden with no 

perceived environmental benefit. To that end, NMMA and Mercury recommend that EPA retain 

the current defect reporting program for PWC and OB engine manufacturers. 

NMMA and Mercury commented that for boat builders and component manufacturers, 

the expanded scope of the defect reporting requirements to include components subject to the 

evaporative emissions standards may overwhelm this industry. A major concern held by NMMA 

members is the ability of small business boat builders and component manufacturers to track the 

requisite information in an industry that is not vertically integrated. A large number of the boat 

builders and component manufacturers are small businesses and do not have the staff or 

sophisticated systems to track warranty claims. In addition, recreational marine dealerships are 

not as sophisticated or as organized as those for light-duty vehicles or for Recreational Vehicles. 

There are many small dealerships that do not have the resources or capabilities to track the 

information required by EPA’s proposed defect reporting program. This makes determining 

whether the investigation and reporting thresholds are triggered particularly difficult and 

burdensome. As stated in the NMMA testimony, there are a number of boat builders that do not 

understand the requirements in this proposed rule or are even aware that a rule exists. Significant 

outreach is needed by EPA and industry to make certain that these companies are aware of the 

requirements and receive the necessary training. To address this problem, NMMA suggests that 

EPA consider delaying the defect reporting requirements and perform a technical review in 

model year 2011 for evaporative emission-related parts. This should provide EPA and NMMA 

with enough time to conduct outreach and training. 

Bombardier commented that BRP has been complying with EPA's defect reporting 

requirements for PWC and outboard engines for the past ten years. BRP has dedicated resources 

to ensure compliance with these requirements. Switching to a new defect reporting system will 

be a burdensome transition requiring significant revisions to BRP's current marine warranty 

reporting process, the implementation of new tracking software and employee training. 

Pleasurecraft Marine commented in a hearing that Section 1068.501 is a lengthy section 

detailing an elaborate method of reporting and correcting emission related defects. This section 

appears more applicable to the automobile industry than the marine industry. Pleasurecraft 

recognizes and agrees with the need for proper and timely problem resolution as well as the 

associated documentation required. However, this method of defect and recall reporting 

represents an extreme burden for small businesses. Therefore they advocate for harmonization 

with the methods outlined in the California Air Resource Board procedures for defect and recall 

protocols. 

Letters: 

Commenter Document # 

NMMA 0688 

Bombardier 0674 

Mercury 0693 

Pleasurecraft Marine (hearing) 0642 

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Chapter 3: Marine SI Engines 

Our Response: 

We are moving to apply the defect-reporting requirements broadly across all our nonroad 

engine programs. For Marine SI engines and for most other engine categories, this moves us 

away from current requirements, which are based on a simple numerical threshold of 25 defects 

regardless of the size of the engine family. We believe this threshold should be scaled to the size 

of the engine family to avoid the burden for manufacturers and EPA to generate and review 

defect reports where the defect rate might be minuscule. Another aspect of the new provisions is 

that they require manufacturers to monitor warranty claims and other available information to 

determine whether they exceed the specified defect thresholds. Under the current regulations, 

there is no clear requirement to monitor available information. We are concerned that 

manufacturers are not taking reasonable steps to get or process available information for making 

these evaluations. 

Since the reporting thresholds are substantially higher than under part 91, the concern for 

increased burden under the new approach is only reinforcing our concern that manufacturers are 

not taking adequate steps today to monitor available information for potential emission-related 

defects. In particular, the commenters’ concern about an overwhelming burden for small 

businesses that are not familiar with regulatory requirements is misplaced. Dealers have no new 

obligations under the defect-reporting requirements. In fact, we would expect dealers to be 

motivated for financial reasons to pass along to the certifying manufacturer detailed information 

about warranty claims or other indications of emission-related defects. Compliance with defectreporting requirements falls entirely on the certifying manufacturer. The certifying manufacturer 

is responsible to keep track of the information coming in from dealers, owners, service 

personnel, and others. When potential emission-related defects exceed the specified thresholds, 

then the certifying manufacturer must investigate further to determine whether there is a need to 

report the emission-related defect to EPA. 

We understand that the evaporative emissions control systems are not susceptible to 

emissions failure because they primarily consist of material solutions rather than moving parts. 

However, manufacturers should be monitoring warranty claims as good business practice, 

therefore the incremental monitoring for evaporative emissions systems is minimal. 

We acknowledge that there would be an unreasonable burden for manufacturers to 

simultaneously follow EPA’s defect-reporting methodology and a different methodology for 

California ARB. We agree that the California ARB defect reporting approach is as protective of 

the environment as the EPA requirement, therefore we will accept their defect reporting program 

as a compliance option under §1068.501(a)(6). 

3.12.6 National security exemption 

What Commenters Said:

 Bombardier commented that BRP is supportive of the US armed forces, and is proud to 

offer specially designed marine spark-ignited engines for their use. Unfortunately, the proposed 

national security exemption requirement of 40 CFR 1068.225 (b) makes it difficult to support 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

our military's need in a timely manner. Under 40 CFR 1068.225 (b), EPA is proposing to only 

issue an exemption without a request, "if it will be used or owned by an agency of the federal 

government responsible for national defense, where the equipment has armor, permanently 

attached weaponry, or other substantial features typical of military combat." The requirement 

"where the equipment has armor, permanently attached weaponry, or other substantial features 

typical of military combat" is unnecessary and burdensome. The final disposition of the engines 

BRP has specially designed and manufactured for military use is often classified information. 

Often, BRP has no way of verifying they will be used on a vessel or equipment that has armor, 

weaponry, or other features of combat craft. As a result, BRP will need to seek a national 

security exemption under the proposed 40 CFR 1068.225 (c). 

BRP commented that 40 CFR 1068.225 (c) allows a manufacturer to request a national 

security exemption with an endorsement by an agency of the federal government responsible for 

national defense. This requirement is in essence identical to the current national security 

exemption of 40 CFR 91.1008 (2). While it is possible to meet this requirement, the current 40 

CFR 91.1008 (2) can result in substantial and unnecessary delays in providing engines for our 

military's use. BRP feels it is imperative the US military receive their engines when they are 

needed without undue delay. BRP supports EPA's efforts to limit national security exemptions to 

agencies of the federal government responsible for national defense. However, the requirement 

to ensure the exempted engine will be used on equipment with armor, weaponry, or other 

attributes associated with combat creates a burdensome and unnecessary step in providing 

support to the US military. 

BRP respectfully requests EPA to revise 40 CFR 1068.225 (b) to state, "Your 

engine/equipment is exempt without a request if it will be used or owned by an agency of the 

federal government responsible for national defense." 

Letters: 

Commenter Document # 

Bombardier 0674 

Our Response: 

The provisions for the national security exemption are unchanged from what currently 

applies under the current regulations in §91.1008. The national security exemption broadly 

applies across programs and has changed little since the inception of EPA’s emission control 

requirements. Defense agencies are very familiar with the distinction between combat and 

tactical applications and their need to request the exemption for tactical applications. We would 

expect engine manufacturers to largely be in a position of responding to orders placed by defense 

agencies. The burden falls on the defense agency to take care of administrative approvals 

associated with national security exemptions. We therefore believe the provisions of §1068.225, 

which have applied for other marine engines for some time, should appropriately be extended to 

apply equally to SD/I engines, as proposed. 

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Chapter 3: Marine SI Engines 

3.13 Small-business issues 

What Commenters Said: 

NMMA noted that for small businesses, EPA is proposing to provide additional lead time 

for compliance with the SD/I engine exhaust standards. NMMA is very supportive of the 

additional compliance flexibility provided for in the rule for small businesses; however, EPA’s 

eligibility criteria as to what constitutes a small business is problematic and is different than the 

Small Business Administration (SBA) definition of what is a “small business.” EPA states in the 

preamble that “[f]or purposes of determining which engine manufacturers are eligible for the 

small business provisions . . . , we are proposing criteria based on a production cut-off of 5,000 

SD/I engines per year.” This same requirement is included in the first part of the proposed 

definition for “small-volume engine manufacturer” in §1045.801. The second part of the 

proposed definition for “small-volume engine manufacturer” in §1045.801 would allow 

manufacturers that exceed the production cut-off to request to be treated as a small business if 

they have fewer than the number of employees defined by the SBA in Title 13 CFR §121.201. 

According to the SBA regulations, this would mean 500 employees for businesses under the 

engine manufacturing NAICS. Notably, these regulations do not refer to a production volume as 

a prerequisite for a business in the particular industry to be classified as a “small business.” 

Furthermore, a production cut-off was not used by EPA to determine which businesses 

participated on the Small Business Advocacy Review Panel on the rule, which served to provide 

advice and recommendations on how to address small business concerns. Two NMMA 

members, Marine Power and PCM, both have well under 500 employees but may occasionally 

produce over 5,000 engines, depending on the year. EPA’s proposal would force these 

manufacturers to request that EPA designate them as a “small-volume engine manufacturer” 

under §1045.635(b) with no guarantee that they would receive the regulatory relief intended for 

small businesses. For these reasons, NMMA commented that EPA should revise §1045.635 so 

that the default is the 500 employee threshold for small-business with the option to qualify as a 

small-volume manufacturer if the 5,000 unit level is not exceeded. NMMA recommended 

specific changes to the regulatory language of §1045.635 to address their concerns. 

NMMA commented that these revisions will preserve the long-standing small business 

threshold for this industry, as established by the SBA, while still preserving EPA’s concept of 

the small-volume manufacturer. If EPA would like to change the small business 500 employee 

threshold to a lower number, NMMA commented that the Agency needs to raise this issue with 

the SBA and Congress. 

Indmar noted that they employ approximately 100 people and produce 10,000 marine 

engines per year. Indmar commented that they would like the definition of small business 

clarified for the purpose of SD/I engines. Section III.F.1 of the preamble discusses the Small 

Business Advocacy involvement with the rule making and includes their definition of a small 

business. Section III.F.2 goes on to define small volume engine manufacturer as 5,000 SD/I 

engines per year but also will consider any manufacturer that meets the SBA definition. There 

are three inboard marine engine manufacturers that are around the 5,000 unit volume definition 

(Indmar included). All of these manufacturers compete for the same boat builders and an unfair 

competitive financial advantage could be gained by a small volume manufacturer. Also a boat 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

builder might switch engine supplier causing a small volume manufacturer (by 5,000 definition) 

to no longer be small volume. Indmar commented that the 5,000 unit cutoff should be removed 

from the definition of small volume engine manufacturer and be replaced with the SBA 

definition of small business. The use of one common definition by SBA should result in less 

confusion down the road. 

Ilmor commented that it is not in favor of using production volume of 5,000 SD/I engines 

per year as the cut-off criteria for determining which manufacturers are eligible for any small 

business provisions within this new rule. Ilmor noted that it favors the industry position that 

EPA should follow the Small Business Administration (SBA) guidelines for defining “smallvolume engine manufacturers,” which is based on number of employees. According to the SBA 

regulations, this would mean a cut-off based 500 employees for businesses under the engine 

manufacturing NAICS. The high-performance sector is the one sector of the marine industry 

that has been exempt from emissions compliance standards by both EPA and CARB. Every 

engine manufacturer within the high-performance sector is effectively a “small volume 

manufacturer.” 

Pleasurecraft Marine noted that they are a small business as defined by the Small 

Business Administration. Pleasurecraft commented that they recommend adoption of the 

universal size standards as used by the Small Business Administration under the North American 

Industry Classification System (NAICS) for EPA’s small volume engine manufacturer 

definition. There are several classifications that could be used to define small businesses, all 

based on the number of employees, rather than units produced. From their perspective, the 

definition is of concern because their business has found itself falling above and below that 

production number that is in the rule. One year it could be applicable and not the following year 

again. They believe that down the line that can create a lot of confusion especially for their 

company. 

Marine Power noted that they originally built engines for the Gulf coast shrimping and 

fishing industry as early as the 1960s. Today we employ about 35 people. There appears to be 

some ambiguity which has been discussed about the definition of a small business. Marine 

Power requested that EPA retain the customary definition of a small business being one less than 

500 employees. They noted that they would possibly fall from one category to another in regard 

to the proposed 5,000 annual production limit. However, in their 32 years of history, they would 

always be a small business based on the SBA criteria. 

Congresswoman Velazquez, Chairwoman of the Committee which oversees the 

Regulatory Flexibility Act (RFA), expressed concerns about the proposed rule issued by EPA 

regarding standards for marine spark ignition engines.) Specifically, she expressed concerns 

about the proposed burden reduction for small business sterndrive and inboard (SD/I) engine 

manufacturers. She noted the agency has chosen not to utilize the size standards established by 

the Small Business Administration (SBA) for small business marine engine and equipment 

manufacturers of 1,000 and 500 employees respectively as a basis for providing small businesses 

with regulatory relief. Instead, the agency is setting a threshold at a production level of 5,000 

engines per year. Although EPA is proposing to allow businesses that exceed the production 

level but fall within the SBA size standards to request treatment as small businesses, the 

uncertainty of this case-by-case approach causes concern. She commented that the proposed unit 

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production threshold will not provide relief for the small businesses in this industry. The 

proposed rule requires a dramatic reengineering of SD/I engines and small businesses need relief 

so federal regulation will not place them at a competitive disadvantage to their larger 

counterparts. 

Congresswoman Velazquez commented that it is important to consider that the disparity 

between large and small businesses in the SD/I market sector is significant. The leading large 

businesses in this sector have tens of thousands of employees. The smaller businesses in this 

sector have less than 100 employees; however, some of them may not be eligible for relief based 

on the proposed production level criteria. She noted that EPA has completed the Small Business 

Advocacy Review Panel process for this rulemaking and during that process the Agency invited 

small marine engine businesses to discuss the flexibilities they require so as not to be placed at a 

competitive disadvantage by the proposed rule. Based on these good faith discussions and the 

disparity between large and small companies in the SD/I market segment, she strongly urges the 

EPA to utilize SBA size standards as the basis of providing burden reduction for small 

businesses. She recommended that the final rule implement the 1,000 and 500 employee 

threshold as the basis for small business burden reduction rather than on a unit production level. 

She commented that if EPA continued to believe the threshold for providing small businesses 

with burden reduction should be based on an annual engine production level, EPA should advise 

the Committee of the necessity for this. 

ECO commented that they agree that small businesses require additional lead time and 

flexibility to comply with the proposed rules. However, using the threshold 500 employees or 

5,000 SD/I engines per year is overly inclusive, providing regulatory flexibility for entities that 

are not truly small businesses. This action, in turn, will cause harm to those companies that truly 

are small businesses. Instead of the current proposal, ECO and recommended that EPA consider 

adopting the definition proposed in 40 CFR 1048.801 for large spark-ignition engines, which 

identifies a small volume engine manufacturer as one with 200 or fewer employees, or less than 

2,000 subject engines produced annually. 

Tohatsu commented that it is quite a tough job for a small manufacturer like itself who 

has total employees of less than 500 people to redevelop and set calibration fuel, ignition timing, 

etc. and also comply with evaporation requirements. And naturally these changes will also 

require a new batch of deterioration testing at 350 hours for all models. Although Tohatsu 

understands that these requirements are necessary, they noted that it is a very time consuming, 

and expensive, process for a small company to meet. Tohatsu commented that the time frame 

should be extended as much as possible to give small manufacturers a realistic chance to comply 

with the new regulations. Unlike many of their competitors that have other divisions in cars and 

motorcycles, Tohatsu produces only outboards. Because of this, Tohatsu commented that it does 

not have the same resources to be able to comply with new regulations as quickly as other 

companies. 

ECO commented that the proposed provisions for small volume engine manufacturers to 

rely on assigned deterioration factors for demonstrating useful life emissions compliance (ref 40 

CFR 1045.240(c)) are critical to the small businesses which produce SD/I engines. ECO 

encouraged EPA to retain this provision in the final rule. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

Indmar 0667 

Ilmor 0658 

Pleasurecraft Marine (hearing) 0642 

Marine Power (hearing) 0642 

Congresswoman Velazquez 0702 

ECO 0712 

Tohatsu (hearing) 0642 

Our Response: 

With regard to the comments on use of a small-volume threshold to provide SD/I engines 

manufacturers with regulatory flexibility, EPA had additional discussions with NMMA on this 

issue after the close of the comment period. (“November 19, 2007 Meeting with National 

Marine Manufacturers Association” EPA memo from Alan Stout to Docket EPA-HQ-OAR2004-0008, November 20, 2007. See docket item EPA-HQ-OAR-2004-0008-0757.) NMMA 

continued to support using a business’s number of employees rather than production volume as a 

basis for determining eligibility for regulatory relief. EPA notes that the SBA’s size standards at 

13 CFR part 121 define small businesses as those that have 1,000 employees or less (for NAICS 

code of 333618), not 500 employees or less as cited by NMMA in its comments. EPA’s concern 

with using the NMMA’s recommended employee cut-off level for marine engine manufacturers 

as the primary criteria for determining eligibility for the rule’s hardship provisions is that 

manufacturers with such high numbers of employees generally should have ample resources to 

devote to complying with EPA’s program, and it would therefore be unnecessary to provide 

regulatory relief for such manufacturers. In addition, manufacturers with around 1,000 

employees would easily be able to produce significantly more than the 5,000 unit limit included 

in the proposed definition. Based on current employment levels for the biggest of the existing 

small business SD/I engine manufacturers, EPA believes it is possible to use an employee limit 

of 250 for the small-volume engine manufacturer definition and still include all small businesses 

as defined under SBA definition. EPA believes a 250 employee limit should be roughly 

consistent with the production level we targeted in our proposal, although some manufacturers 

would likely be able to produce more than 5,000 units. Therefore, EPA is adopting a smallvolume engine manufacturer definition of 250 employees or less for the final rule. Under the 

small-volume engine manufacturer definition being adopted, there will be no option to consider 

the production volume instead of the 250 employee count. 

All of the small business SD/I engine manufacturers identified by EPA have significantly 

fewer employees than the small business size standard established by SBA. As noted above, 

EPA believes that a business with close to 1,000 employees should have the resources available 

to comply with the new requirement without the need for the flexibilities proposed for small 

volume SD/I engine manufacturers. For this reason, we are adopting a 250 employee limit. EPA 

believes this limit will cover all of the existing small business SD/I engine manufacturers (as 

defined by SBA), but places a reasonable limit on how large a company could grow before they 

are no longer eligible for EPA’s flexibilities for small volume engine manufacturers. 

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Chapter 3: Marine SI Engines 

EPA has the authority and discretion to select the criteria for determining which “small” 

manufacturers are eligible for the flexibilities being offered under a regulatory program. EPA’s 

selection of eligibility criteria for purposes of establishing regulatory thresholds is not governed 

by the Regulatory Flexibility Act (RFA) as amended by the Small Business Regulatory 

Enforcement Fairness Act of 1996 (SBREFA). The RFA is a purely procedural statute. United 

States Cellular v. Federal Communications Comm’n, 254 F.3d 78 (D.C. Cir. 2001). Under the 

RFA, EPA is required to use SBA’s size standards to define “small businesses” for purposes of 

complying with the RFA’s requirements, unless it adopts an alternative definition. EPA used the 

SBA definitions for purposes of its compliance with the requirements of the RFA, including for 

the identification of Small Entity Representatives (SERs) for the Small Business Advocacy 

Review Panel convened pursuant to section 609(b) of the RFA and for analyzing the impacts of 

the proposed rule on small businesses in the Initial Regulatory Flexibility Analysis (IRFA) which 

was included in Chapter 10 of the Draft RIA. 

EPA believes that its adoption of flexibilities for small-volume manufacturers does not 

amount to establishing a size standard for a “small business concern.” The regulatory 

flexibilities simply identify options available to manufacturers to aid in the transition to new 

emission standards. Even if EPA's adoption of these regulatory flexibilities could be 

characterized as a size standard, EPA shared this approach during the SBREFA Panel process 

and provided SERs with the criteria we ultimately proposed. Additionally, EPA’s proposal 

included flexibility eligibility criteria based on the annual production volume, but also included 

the option to request treatment as a small-volume engine manufacturer if they demonstrated they 

met the SBA size standards. Finally, SBA is part of the inter-agency review process and has 

reviewed and cleared the final rulemaking package. 

For OB/PWC engines, EPA is also revising the definition of small volume engine 

manufacturer. EPA originally proposed a definition based on a production level of 5,000 units 

per year. The revised definition is the same as that being adopted for small volume SD/I engine 

manufacturers noted above and is based on number of employees rather than production. EPA 

believes a 250 employee limit should be roughly consistent with the 5,000 unit production level 

we targeted in our proposal. To qualify for the flexibilities for small volume OB/PWC engine 

manufacturers, a manufacturer would need to have no more than 250 employees. 

With respect to Tohatsu’s comments on additional time for small OB/PWC engine 

manufacturers to meet the exhaust standards, it can be noted that EPA is delaying 

implementation of the standards for all OB/PWC engine manufacturers. EPA is delaying the 

exhaust standards for OB/PWC engines from 2009 to 2010. Tohatsu had nine OB/PWC engine 

families certified with EPA in the 2007 model year. Of these nine families, four of them have 

Family Emission Levels (FELs) below the new HC+NOx standards. In addition, all of the 

engine families have CO levels below the new CO standards, although three of the families are 

close to the standard. Given that we will continue the ABT program for HC+NOx, given that we 

will allow averaging for CO emissions, and given the extra year of leadtime, we believe Tohatsu 

(and other small volume OB/PWC engine manufacturers) should have sufficient time to comply 

with the new exhaust emission standards by 2010. (See Section 4.10 of this document for further 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

discussion of Tohatsu’s comment with regard to the evaporative emission standards for Marine 

SI engines and vessels.) 

With regard to the comment on the use of assigned DFs for small volume engine 

manufacturers, EPA is retaining the provision for the final rule as proposed. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4 Evaporative Emission Standards and Related 

Requirements for Nonroad SI Engines and Equipment 

What We Proposed: 

The comments in this section generally correspond to Sections VI and VII of the 

preamble to the proposed rule, where we describe the proposed emission standards and 

certification procedures associated with evaporative emissions from Small SI equipment and 

Marine SI vessels. The applicable regulatory provisions for these proposed requirements are in 

40 CFR parts 90, 1045, 1054, and 1060. The Regulatory Impact Analysis describes the 

feasibility of these standards, special provisions that apply to small businesses, and alternative 

standards under consideration in Chapters 5, 10, and 11, respectively. 

See Chapter 1 of this document for a discussion of issues related to Large SI engines and 

equipment and to recreational vehicles. 

4.1 General approach 

4.1.1 Support proposed standards 

What Commenters Said: 

EMA supported the basic evaporative standard requirements proposed by EPA. EMA 

specifically requested that EPA make additional efforts to harmonize test methods with the 

California ARB Tier III requirements. Harmonizing soak temperatures, tolerances, measurement 

methods, and reporting requirements would substantially reduce regulatory burden without 

reducing environmental benefit. 

California ARB recommended that EPA either modify its proposal to match the 

California program or allow California test results to meet the EPA requirements. 

NACAA supported EPA’s inclusion of evaporative emission standards for all nonroad 

spark-ignition equipment and watercraft covered by this rule. NACAA noted that it is pleased 

that EPA has proposed fuel line controls in 2008 for Class I and II small spark-ignition engines 

and tank permeation, diffusion and running loss standards, as well. Likewise, for marine sparkignition engines, NACAA supported the evaporative emission standards included in the proposal 

and encouraged EPA to implement these standards on the schedule identified. 

Pennsylvania DEP supported the proposed standards and implementation schedule for 

marine spark-ignition engines and vessels. MARC AQ Forum supported the evaporative 

emissions standards included in this proposed rule for non-road spark ignition and marine 

engines. 

NESCAUM supported EPA’s effort to harmonize the federal emissions standards with 

those standards already adopted in California. However, NESCAUM commented that the 

4-1 
Chapter 4: Evaporative Emissions 

effective dates for the evaporative emissions standards should be sooner and should match the 

effective dates of the comparable California standards or follow California by no more than one 

year. 

Environmental Defense applauded EPA’s proposal to establish for the first time 

evaporative emission standards for spark-ignition marine and small engines. Reducing the 

vaporous air toxics and other pollutants emitted from SI engines will greatly reduce the 

inhalation based cancer and non-cancer health risks posed from these sources. Environmental 

Defense commented that they believe all types of evaporative emissions should be reduced from 

all sources. 

Delphi generally supported the proposed evaporative emission requirements for nonroad 

SI engines and equipment. 

Trident Rubber commented that it agreed with and supported most of the EPA's proposal 

to control evaporative and exhaust emissions from SI engines and fuel systems on boats. They 

particularly supported the proposed provisions related to low permeation marine fuel line hose 

and assemblies. 

Letters: 

Commenter Document # 

NACAA 0651 

Environmental Defense 0648 

NESCAUM 0641 

MARC AQ Forum 0696 

California ARB 0682 

Delphi 0638 

Trident Rubber 0636 

Pennsylvania DEP 0676 

EMA 0691 

Our Response: 

We are largely finalizing the evaporative emission standards as proposed. In several 

cases we adjusted regulatory provisions in response to public comments. Some of the changes in 

the final rule are based on new information since the proposal was published. These 

modifications are discussed, in the appropriate sections, throughout this chapter. 

Several issues have been raised by commenters related to the harmonization of federal 

and California standards, test procedures, and other requirements. These comments are 

addressed throughout this chapter. Although California has evaporative emission standards for 

Small SI equipment, it should be noted that California has not yet established evaporative 

emission standards for marine vessels. 

4-2
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.1.2 Applicability and general concerns 

What Commenters Said: 

EMA commented that engines utilized for auxiliary power in highway products should be 

specifically excluded from §1060.1. For example, generators for motor homes where the fuel is 

supplied from the main vehicle fuel tank should not be covered by the proposed rule. If EPA 

does not exclude such engines/equipment from the final rule, EMA commented that the only 

requirement that should apply is the requirement that addresses the fuel line used to connect the 

engine to the vehicle fuel tank. Further, if such engines/equipment are not excluded, EMA 

commented that EPA must clarify that vehicle manufacturers producing equipment that utilize 

such engines are not required to certify to the Small SI engine related provisions. 

EMA noted that §1060.5(e)(3) refers the engine manufacturer to 40 CFR Part 1054, and 

Part 1054 refers back to Part 1060. EMA commented that these circular references are confusing 

and unnecessary. In order to provide a clear and concise regulatory scheme, all evaporative 

requirements should be included in Part 1060. 

NMMA commented that NMMA members have only a few remaining concerns 

regarding the technology required by the proposal. Catalysts, carbon canisters, and low 

permeation hoses are available and can be incorporated into marine exhaust and fuel systems. 

However, what does concern NMMA and its members is that these components are not 

necessarily at the point at which they are either commercially available or tested sufficiently in 

the field to assure boating safety or consumer choice. To address these concerns, NMMA 

recommends additional lead time for the implementation of certain aspects of the exhaust and 

evaporative emission standards or a phase-in approach. As NMMA testified to at the public 

hearing, there are 3,000 boat builders in the U.S.; only 400 of these are NMMA members. For 

the remaining boat builders, they cannot say with any certainty whether these businesses are 

even aware of this rulemaking. Thus, they cannot stress enough the importance of EPA giving 

sufficient lead time for compliance to assure that the Agency has the opportunity to perform the 

necessary outreach and education to ensure that small businesses are aware of the rule 

requirements and understand the regulatory compliance obligations. 

Letters: 

Commenter Document # 

EMA 0691 

NMMA 0688 

Our Response: 

The proposed rule included language in §1054.20 to specifically state that the new Small SI 

evaporative requirements do not apply to engines used for auxiliary power on motor vehicles (or 

marine vessels). We agree that this is necessary to avoid overlapping or conflicting requirements 

where these fuel systems could already be subject to other standards. We would still expect 

engine manufacturers to use fuel tanks and fuel lines that meet Small SI standards to the extent 

they install these components and are unsure that the engines will be installed in motor vehicles 

4-3 
Chapter 4: Evaporative Emissions 

(or marine vessels). We have added language to §1060.1 to further clarify the applicability of 

standards for these products. 

The regulatory approach for our nonroad evaporative standards is to include in part 1060 

everything that one would need to know for meeting applicable requirements. This is especially 

designed to allow component manufacturers to have all applicable requirements included on one 

location as much as possible. In some cases, this involves a reference to an exhaust standardsetting part such as part 1054 for detailed provisions that apply uniquely for a particular category 

of engines. The most prominent example of this is related to emission credits. Provisions for 

emission credits apply only for equipment manufacturers (not component manufacturers) and 

emission credits are generally not exchangeable across engine categories, so these are not 

included in part 1060. We include a summary of the evaporative emission standards in the 

exhaust standard-setting parts to accommodate a similar interest for engine manufacturers to 

have ready access to a description of what standards apply for their products. EPA and 

manufacturers will gain much experience in the coming years regarding the certification 

practices. We will be ready to help people understand their compliance obligations and may 

revise the regulations in the future to avoid confusion if it becomes clear that certain changes are 

needed. 

We address NMMA’s concerns about lead time for the various requirements in the following 

sections. We agree that we will need to make an extensive effort to help boat builders and others 

understand the new requirements and look forward to working with NMMA toward that end. 

4.2 Small SI standards and lead time 

4.2.1 Components covered 

What Commenters Said: 

EMA and OPEI supported EPA’s proposed requirement that fuel line permeation 

standards apply only to liquid fuel lines. EMA and OPEI noted that EPA’s own data confirms 

the fact that permeation emissions from vapor lines and very small surface area components 

(such as primer bulbs) do not require controls. EMA and OPEI suggested that vapor lines and 

filler necks that may be in constant contact with liquid fuel should be held to the same 

permeation requirement as other fuel lines. However, filler neck and tank assemblies that 

include features to limit the possibility of liquid fuel being in constant contact with the filler neck 

(e.g. overfill valves, venting arrangements, and filler necks above the maximum fuel level in the 

tank) should be considered vent line and should not be subjected to permeation requirements. 

EMA also commented that the proposed language in §90.3 includes a definition of “Fuel 

Line” pursuant to 40 CFR Part 1054.801. EMA commented that the proposed wording in 

§90.127(a)(1) could be confusing and should be revised to reference the proposed fuel line 

definition. Accordingly, §90.127(a)(1) should be revised to read as follows: “... This standard 

applies to any fuel line.” 

Honda requested that EPA allow engines less than 80cc to comply with both handheld 

exhaust and evaporative emission standards. Honda agreed with the proposal as written that 

4-4
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

engines less than 80cc should be handheld and asked that the language on evaporative emissions 

be clarified to include these engines. 

Letters: 

Commenter Document # 

EMA 0691 

OPEI 0675 

Honda 0705 

Our Response: 

The new standards will apply to fuel lines, including hose or tubing that contains liquid 

fuel. This includes fuel supply lines but not vapor lines or vent lines that are not normally 

exposed to liquid fuel (see the definition of “fuel line” in §1054.801). We consider fuel return 

lines for handheld engines to be vapor lines, not fuel lines. Data in Chapter 5 of the Final RIA 

suggest that permeation rates through vapor lines and vent lines are already lower than the new 

standard; this is due to the low vapor concentration in the vapor line. In contrast, permeation 

rates for materials that are consistently exposed to saturated fuel vapor are generally considered 

to be about the same as that for liquid fuel. The new standards also do not apply to primer bulbs 

exposed to liquid fuel only for priming, but would apply to primer bulbs directly in the fuel 

supply line. For comparison, this standard will apply to marine filler necks that are filled or 

partially filled with liquid fuel after a refueling event where the operator fills the tank as full as 

possible. In the case where the fuel system is designed to prevent liquid fuel from standing in 

the fill neck, the fill neck will be considered a vapor line and not subject to the new fuel line 

permeation standard (see Section 4.3.2). 

We agree with EMA that the language at the end of §90.127(a)(1) is duplicative because 

it is included in the definition of “fuel line” and have modified the text to specify “any fuel line.” 

We have clarified the regulations stating that all Small SI engines at or below 80cc may 

certify to the handheld evaporative standards, regardless of the type of application into which the 

engine is ultimately placed. 

4.2.2 Fuel line permeation standards and lead time 

What Commenters Said: 

EMA commented that the final regulation will not be implemented in time for 

manufacturers to incorporate the fuel line requirements for nonhandheld engines into 2008 model 

year engines. However, EMA member companies, and a significant percentage of equipment 

manufacturers that utilize EMA member company engines, will use low permeation fuel lines on 

a voluntary basis during the 2008 model year (which will provide substantial environmental 

benefits). Due to the negative lead time associated with the implementation of the final rule, 

EMA commented that EPA must provide the flexibility necessitated by the situation. Engine 

manufacturers can’t be required to comply with retroactive standards that have not yet been 

implemented. 

4-5 
Chapter 4: Evaporative Emissions 

Honda also requested that EPA recognize that the requirement for compliance in 2008 

with certain provisions may not be feasible for 100 percent of engines or products. Section 

90.127(a) and (b)(1) requires demonstration of compliance with fuel line permeation from 

nonhandheld engines and equipment for the 2008 model year. In some cases, manufacturers may 

produce both California and 49-state compliant product for 2008, therefore compliance with this 

proposed requirement would not be feasible. Honda suggested that 2009 should apply to all 

engine and equipment manufacturers, not just small volume producers. 

OPEI commented that due to the expected effective date of the final rule and the 

imminent date of the engine manufacturer's 2008 model year, it is more than likely that the final 

rule will provide negative lead time for implementation of the fuel line permeation standards for 

nonhandheld products. As a result, OPEI commented that certification of compliance with such 

standards is not feasible and the regulatory requirements must be delayed until the 2009 model 

year. While OPEI member companies, and a significant percentage of equipment manufacturers 

that utilize OPEI member company engines, will use low permeation fuel lines on a voluntary 

basis during the 2008 model year (which will provide substantial environmental benefits), OPEI 

commented that EPA must nonetheless delay the effective date of such regulations. 

OPEI supported EPA’s reasoning for the given timing for implementing low permeation 

fuel lines on handheld products. Manufacturers need sufficient lead-time to safely design, select, 

manufacture, test and implement these new lines. 

California ARB noted that EPA has proposed a fuel line permeation standard of 15 

g/m2

/day that is the same as those for recreational vehicles. The small off-road 

engine/equipment program has implemented this standard since 2006. California ARB 

commented that its component certification data for fuel hoses (included in Attachment 1 of 

California ARB’s comments) supports setting a lower standard. Therefore California ARB 

recommended a more stringent standard of 5 g/m2/day at 40°C. 

NACAA commented that they are pleased EPA has proposed fuel line controls in 2008 

for Class I and II small spark-ignition engines. 

Environmental Defense commented that they support EPA’s [fuel line permeation] 

standard for Small SI engines as it is identical to California’s. They also supported EPA’s nearterm implementation dates of 2008 and 2009. As EPA recognizes, California currently requires 

the use of a low-permeation fuel line in Small SI equipment such as walk-behind lawn-mowers. 

Manufacturers of fuel lines used in SI small equipment will be able to draw from readily 

available technology used to meet the CA standard. NACAA commented that they believe a 

lead time of two years provides the manufacturers ample time in which to design fuel lines that 

will meet the proposed standard and would strongly oppose the adoption of any later 

implementation date. Indeed, we would like to see evaporative emission standards for all types 

and classes of SI small and marine engines implemented in the shortest time period feasible. 

Briggs and Stratton commented that the proposed fuel tank and fuel line permeation 

levels are acceptable. 

4-6
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

OPEI 0675 

Environmental Defense 0648 

Suzuki 0698 

California ARB 0682 

Briggs and Stratton 0657 

EMA 0691 

Honda 0705 

Our Response: 

We are finalizing the proposed fuel line standard of 15 g/m2

/day for Small SI equipment. 

This permeation rate is at 23°C on a test fuel containing 10 percent ethanol. This hose 

permeation standard is consistent with the existing recreational vehicle standard and the new 

standard for marine vessels being finalized in this rule. The move toward low-permeation fuel 

lines in recreational vehicles—and further development work in this area since the first proposed 

rule for marine evaporative emissions—demonstrates that low-permeation fuel lines are available 

on the market today for Small SI equipment. In addition, many manufacturers are already using 

low-permeation technologies in response to permeation standards in California. However, we 

recognize that this rule has not been finalized until well into 2008. We are therefore requiring 

that the hose permeation standard apply beginning January 1, 2009 for nonhandheld Small SI 

equipment. 

4.2.3 Fuel line permeation– cold-weather fuel lines 

What Commenters Said: 

OPEI commented that low-permeation fuel lines should not be used on cold weather 

products (like chainsaws and ice augers) because the stiffer lines would be much more likely to 

crack and break during high-vibration uses (such as chainsaws) at cold temperatures. 

Accordingly, OPEI strongly urged EPA to finalize the proposed, more appropriate permeation 

standards and related effective dates for fuel line used on cold-weather, handheld products. 

Lines with permeation levels at 175 grams should provide the needed mechanical flexibility in 

material to comply. Because manufacturers must use lines with perm levels at about 175 

g/m2

/day, using ABT to offset the credits needed if the standard on these product types was 15 

g/m2

/day, would not be possible. 

OPEI commented that the products outlined in the definition of cold weather provided for 

in part 1060 are acceptable and necessary for safety reasons. All of the indicated products are 

used in extremely cold environments. 

After the comment period closed, OPEI commented that the data they had submitted on 

handheld product fuel line permeation rates, prior to the NPRM, was based on a test fuel of 90 

percent gasoline and 10 percent ethanol (E10). However, the proposed fuel line permeation 

4-7 
Chapter 4: Evaporative Emissions 

standards were based on fuel CE10,1 which results in significantly higher permeation rates. 

Further, OPEI provided additional test data on permeation rates from cold weather fuel lines 

tested on either E10, CE10, or both test fuels.2

 Based on this test data, OPEI recommended that 

the permeation standard for cold-weather fuel lines be 290 g/m2

/day with E10 as a test fuel. 

OPEI stated that the higher permeation limit was necessary to account for high variability in the 

test results. They further commented that a standard of 225 g/m2

/day would be possible if 

coupled with an averaging program. 

Letters: 

Commenter Document # 

OPEI 0675 

OPEI 0811 

Our Response: 

Handheld equipment manufacturers have raised concerns that fuel lines constructed of 

available low-permeation materials may not perform well in some handheld applications under 

extreme cold weather conditions such as below -30°C. These products often use injected molded 

fuel lines with complex shapes and designs needed to address the unique equipment packaging 

issues and the high vibration and random movement of the fuel lines within the overall 

equipment when in use. Industry has expressed concern and the data in Chapter 5 of the Final 

RIA suggest that durability issues may occur from using certain low-permeation materials in 

these applications when the weather is extremely cold and that these could lead to unexpected 

fuel line leaks. Handheld equipment types that could be considered as cold-weather products 

include cut-off saws, clearing saws, brush cutters over 40cc, commercial earth and wood drills, 

ice augers, and chainsaws. 

As discussed in the Final RIA, rubbers with high acrylonitrile (ACN) content are used in 

some handheld applications. These materials have about half the permeation of lower ACNcontent rubbers also used in handheld applications. To capture the capability of these materials 

to reduce permeation emissions without creating other issues for cold weather products, we are 

adopting a set of declining fuel line permeation standards for cold-weather products that would 

phase in from 2012 to 2016. The standard for cold-weather products starts at 290 g/m2

/day in 

2012 and decline to 275 g/m2

/day in 2013, 260 g/m2/day in 2014, 245 g/m2/day in 2015. The 

standard for 2016 and later model years is 225 g/m2/day. The standards would apply to all coldweather products, including small volume families. Manufacturers would be allowed to 

demonstrate compliance with the 2012 through 2015 standards with a fuel line averaging 

program for cold-weather products. Beginning in 2016, fuel line averaging would no longer be 

available for cold-weather products and all fuel lines on cold-weather products would have to 

comply with the 225 g/m2/day standard. These standards are based on testing with E10 test fuel 

(not CE10), consistent with the data used to establish the emission standards. For any future 

emission standards for cold-weather fuel lines, we would consider aligning fuel specifications 

(and emission levels) with those established for other fuel lines. 

1

 Fuel CE10 denotes 90% ASTM Fuel C (50% isooctane, 50% toluene) and 10% ethanol 2

 “Discussions with Handheld Manufacturers on Cold-Weather Fuel Lines,” EPA memo from Phil Carlson to 

Docket OAR-2004-0008, May 30, 2008. 

4-8
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.2.4 Tank permeation standards and lead time 

What Commenters Said: 

Environmental Defense stated that it supports the proposed fuel tank permeation 

standards as they are consistent with the California standards. Environmental Defense 

recommended earlier implementation dates for the tank permeation standards. They commented 

that an earlier implementation date of 2008, rather than 2009, is feasible for those handheld 

equipment manufacturers currently using low-permeation fuel tanks in products sold in 

California. They also requested that the tank permeation implementation dates for other 

handheld equipment manufacturers be moved up by at least a year. Environmental Defense also 

argued that the implementation dates for fuel tanks on nonhandheld equipment are too delayed. 

Environmental Defense commented that coordinating tank permeation implementation dates 

with SI small engine exhaust implementation dates is unnecessary. First, they noted that they 

object to the much delayed implementation dates for the engine exhaust standards and do not 

believe EPA has adequately explained the basis for the proposed long lead times. Second, they 

see no reason why the implementation timetable for evaporative controls must be tied to that for 

exhaust controls because EPA nowhere states that newer low-permeation fuel tanks used to 

reduce evaporative emissions cannot be combined with advanced fuel injection technology or 

catalysts used to reduce exhaust emissions. 

The California Air Resources Board expressed support of fuel tank permeation standards 

but stated that the standard of 1.5 g/m2

/day should be based on testing on CE10 at 40°C rather 

than at 28°C. California ARB commented that component certification data from the small offroad engine program in California supports setting a lower standard. California ARB also 

commented that the phased-in schedule to meet the fuel tank permeation standards is too lengthy 

and that two years is sufficient time to allow manufacturers to design and produce equipment 

meeting the new evaporative standards. California ARB pointed out that the control technology 

is readily available and currently used in lawn and garden equipment in California. 

Arkema commented that it supplies PetroSeal technology and is eager to work with tank 

manufacturers to help them meet the tank permeation standards. This technology is a two-layer 

fuel tank. The inner layer is Rilsan Polamide 11, which is an engineered polymer which may be 

used to create a permeation barrier in rotation-molded fuel tanks. Arkema stated that this 

specialty nylon, which is used in automotive fuel lines, gives excellent resistance to fuel 

permeation, and is a tough, impact-resistant polymer. Arkema commented that this material is 

dimensionally stable, molds very easily and is manufactured from a renewable resource (100 

percent bio based from a vegetable oil). In a low-permeation, roto-molded fuel tank, the the 

outer side of the layer is metallized polyethylene which has an excellent resistance to alcohol 

permeation and molds very easily. The inner layer is the PA11 which is designed to adhere with 

the outer layer to ensure the structural integrity of the tank and to ensure minimal permeation. 

As a result, Arkema concludes that tanks manufactured with PetroSeal are very low permeation, 

very tough and cost-effective. 

Arkema commented that the PetroSeal technology meets current EPA permeation 

regulations as tested by EPA laboratories (see the RIA) and has received a California ARB 

4-9 
Chapter 4: Evaporative Emissions 

exemption for the small off road and recreational vehicle tanks. Arkema also stated that the 

tanks using this construction have been demonstrated to meet US Coast Guard requirements for 

mechanical strength and fire resistance for permanently installed marine fueled tanks. Arkema 

had a ten gallon and 40 gallon fuel tank manufactured and tested by Imanna labs. In addition, a 

lawn and garden fuel tank using this technology passed the SAE J288 snowmobile impact test. 

Arkema commented that PetroSeal is a commercially active technology today and they are 

selling this material for use in motorcycle fuel tanks. 

Solar Plastics commented that they have conducted an active research and development 

effort for many years and that numerous tooling, material, and processing concepts have been 

invented, evaluated, or optimized in their test facility. Solar has been working with Arkema and 

now produces multi-layer rotation-molded fuel tanks. Solar Plastics commented that it has 

established safe, reliable, and consistent processes to mold the two layer PetroSeal material 

system. Solar asserted that these molded tanks exhibit excellent adhesion between layers, impact 

strength that meets various industry standards, and permeation resistance well within proposed 

standards. PetroSeal fuel tanks molded by Solar Plastics satisfy durability requirements adopted 

by the marine, and lawn and garden equipment industries. These include ambient and cold 

temperature impacts, and burn tests. Molding methods are cost efficient, and utilize the same 

tooling and machinery that produce single layer tanks. Based on these considerations, Solar 

Plastics concluded that technology is available today to rotation-mold fuel tanks that meet the 

proposed evaporative emissions standards. 

Centro commented that, in anticipation of low permeation requirements for fuel tanks for 

Small SI equipment and for boats, they have worked hard over the last five years to develop a 

solution that meets all requirements. Centro stated that they have a solution that is as durable as 

current rotation-molded tanks and meets all other criteria. Centro commented that they have 

invested hundreds of thousands of dollars in successfully developing and testing this technology, 

and that it would be a disservice to the environment to delay tank permeation standards. 

Briggs & Stratton commented that they find the proposed fuel tank and fuel line 

permeation levels to be acceptable. OPEI commented that the effective dates for fuel tank 

standards on handheld tanks are very aggressive (phase-in begins in 2009) and that this will 

require accelerated development and negotiation with production sources. OPEI stated that it 

accepts the aggressive effective dates. 

EMA, OPEI and Briggs & Stratton commented that the proposed alternative fuel tank 

standard of 2.5 g/m2

/day standard at 40°C is not supported by theory or literature to be 

equivalent to the 1.5 g/m2

/day standard at 25°C. They stated that the alternative standard should 

be changed to 3.0 g/m2/day at 40°C. OPEI and Briggs & Stratton commented that, for handheld 

structurally integrated tanks, the 40°C requirement should be 5.0 g/m2

/day. California ARB 

commented that the alternative of 2.5 g/m2/day at 40°C suggested by U.S. EPA should not be an 

option because this standard is too lenient based on certification data which supports a tougher 

standard. 

OPEI submitted an additional comment after the close of the comment period regarding 

rotation-molded fuel tanks. They supported a delay in the permeation requirements for rotation4-10
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

molded fuel tanks instead of allowing a certain number of noncompliant tanks in coordination 

with the Transition Program for Equipment Manufacturers. 

Letters: 

Commenter Document # 

OPEI 0675 

Environmental Defense 0648 

California ARB 0682 

Briggs and Stratton 0657 

EMA 0691 

Arkema (hearing) 0642 

Solar Plastics (hearing) 0642 

Centro 0737 

OPEI 0793 

Our Response: 

During the development of the proposed rule, we worked closely with the fuel tank 

industry to understand their products, business practices, and production processes. Information 

gathered from these interactions was used to craft the proposed regulatory provisions related to 

controlling gasoline fuel tank permeation emissions. During these discussions, important issues 

were identified with respect to concerns regarding the timing and technical feasibility of 

controlling permeation emissions from fuel tanks on Small SI equipment. We have concluded 

that the final fuel permeation standards are technologically feasible and appropriate for Small SI 

fuel tanks. This conclusion is supported by data presented in the Regulatory Impact Analysis by 

comments from fuel tank manufacturers. Issues specific to rotation-molded fuel tanks are 

discussed, in more detail, under Section 4.3.5. 

We are finalizing the fuel tank permeation implementation dates as proposed. In response 

to comments requesting an earlier implementation date, given the timing of this final rule, an 

implementation date of 2008 is clearly not feasible, even for fuel tanks already certified in 

California. We also do not believe that the standards for other fuel tanks should be pulled ahead, 

relative to the proposal. Our final implementation dates are based on our best estimate of how 

much lead time is necessary to bring low permeation fuel tanks to production, especially given 

the large number of fuel tank manufacturers that are small businesses. We considered that some 

manufacturers may be capable of bringing part of their product line in compliance with the fuel 

tank permeation standards early. In order to provide an incentive for these early reductions, we 

finalized an early credit program. 

We are finalizing the optional alternative standard of 2.5 g/m2

/day at 40°C as proposed. 

This alternative standard is intended to provide flexibility to manufacturers that wish to perform 

a single permeation test for certification to EPA standards and for use in certifying to the 

California ARB Small SI standards. The intent of the higher limit of 2.5 g/m2/day is to account 

for increased permeation rates at elevated temperature. This increased limit is not intended to 

represent how an average tank may perform, but rather to provide reasonable assurance that a 

tank certified at the higher temperature would pass the primary standard of 1.5 g/m2

/day at 28°C. 

4-11 
Chapter 4: Evaporative Emissions 

This adjusted standard at 40°C is based on data presented in the RIA and is intended to account 

for variability in how different materials will respond to increases in temperature. 

We respond to OPEI’s comment related to lead time for rotation-molded fuel tanks in 

Section 2.7.6. 

4.2.5 Tank permeation– structurally integrated fuel tanks 

What Commenters Said: 

OPEI expressed support for EPA's proposed permeation standards and flexibilities for 

"structurally integrated" fuel tanks, which are also subject to unique production and operating 

conditions, including cold-weather and high vibration. They commented that the flexibilities 

EPA has provided for, while challenging in terms of permeation reduction, should allow 

manufacturers to engineer safe, practical and cost effective solutions. 

Environmental Defense objected to the fuel tank permeation standard proposed for 

structurally integrated fuel tanks on handheld equipment stating that it was too lax. They noted 

that California’s standard requires fuel tanks to emit no more than 2.0 grams per square meter 

per day and that EPA’s proposed standard of 2.5 grams per square meter per day falls short of 

this standard by a factor of 25%. Environmental Defense commented that the California ARB 

standards represent an essential benchmark necessary to protect human health and that therefore 

the federal standards should be at least as stringent. They also requested that the implementation 

dates for structurally integrated fuel tanks be moved up by at least a year to 2010. 

Letters: 

Commenter Document # 

OPEI 0675 

Our Response: 

We tested structurally integrated fuel tanks from four handheld equipment manufacturers 

at 29̊C on both gasoline and s 10 percent ethanol blend. The test results, which are presented in 

Chapter 5 of the RIA, suggest that structurally integrated fuel tanks are capable of meeting the 

standards using their current materials. In the cases where the permeation rates were higher than 

the standards, it was observed that the fuel cap seals had large exposed surface areas on the Orings, which were not made of low permeation materials. Further data was collected by the 

handheld equipment industry after the proposal. In this testing, they investigated the effect of 

fuel type and gasket material on the permeation results. These test results suggested that 

permeation can be reduced significantly by using a low permeation material, such as FKM, for 

the seal on the fuel cap. In addition, data on aged tanks suggested that NBR o-rings may 

deteriorate in-use such that the permeation rate (or vapor leak rate) through the seal increases 

greatly. Based on this test data, we are finalizing a more stringent fuel tank permeation standard 

of 1.5 g/m2

/day for structurally integrated fuel tanks. However, we are retaining the 2011 

implementation date in the proposal to give manufacturers sufficient time to address any design 

changes, especially for fuel cap seals, that may be necessary. 

4-12
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Manufacturers have expressed concerns with the long term durability of known lowpermeation elastomers in cold-weather applications. At the same time, manufacturers have 

commented that existing fuel cap gasket/o-ring materials may degrade in the field after one year 

(depending on weather and fuel type) in such a way as to have excessively high permeation rates, 

but still prevent liquid fuel leaks. To address this issue, we are allowing manufacturers to treat 

fuel cap seals, on cold-weather equipment, as allowable maintenance items that should be 

replaced annually. In the case of an in-use evaluation, any elastomeric fuel cap seal, over one 

year old, on cold-weather handheld equipment would be replaced prior to preconditioning the 

tank for permeation testing if the manufacturer specified this scheduled maintenance for the fuel 

cap. At the same time, it is not certain that low-permeation materials will deteriorate when used 

for fuel cap seals in cold-weather products. We intend to perform testing on fuel cap seals to 

determine the appropriateness of allowing manufacturers to specify scheduled maintenance to 

address these concerns. In the event that durable materials are identified, we may remove the 

provision allowing for this scheduled maintenance for purposes of compliance with fuel tank 

permeation standards. 

4.2.6 Tank permeation– fuel caps 

What Commenters Said: 

EMA, OPEI and Briggs & Stratton commented that EPA should not impose separate and 

additional regulation (beyond CARB) of fuel cap permeation under the final Phase 3 rule. They 

argued that the emission contributions for fuel caps are very small compared to the overall fuel 

tank-control achieved. EMA and Briggs & Stratton commented that the permeation 

contributions of the caps may be accurately estimated to range from 0.021 and 0.086 g/day, for a 

typical Class I engine and the largest Class II engines, respectively, at 40°C. This estimate 

assumed that fuel caps are made of untreated HDPE (~14 g/m2

/day), though they commented 

that most fuel caps are made of lower permeating materials. 

EMA and OPEI commented that engine and equipment manufacturers that certify 

products to the CARB standards already will have significant tank permeation testing data that 

does not include the fuel tank cap. Due to the difficulties involved with stabilization of the tank 

and the integrity testing requirements, they commented that such fuel tank permeation testing 

requires a substantial investment of time and effort on the part of the manufacturer. They 

concluded that the additional testing requirements would be unduly burdensome with diminished 

environmental benefits. 

If fuel cap testing is absolutely deemed necessary, OPEI believes that allowing fuel caps 

to be tested separately from fuel tanks for permeation emission adds flexibility with no 

degradation to the environment. A single fuel cap may be used on several different fuel tank 

families. Fuel caps and fuel tanks may be molded by different manufacturers who then must 

submit the certification on their products and obtain the certificates of conformity. 

OPEI noted that fuel tank caps can affect control of running loss emissions and/or 

diffusion emissions. Because fuel caps are generally produced by a different manufacturer than 

the fuel tank, OPEI argued that the proposed rule would require the fuel cap to be certified 

4-13 
Chapter 4: Evaporative Emissions 

separately from the fuel tank. However, the engine or equipment manufacturer that is 

responsible for certification of the running loss and diffusion control requirements dictates the 

features associated with the fuel cap design. Accordingly, the fuel cap manufacturer would be 

responsible for certifying a product the design of which it does not control. In order to rectify 

this situation, OPEI recommended that either the engine or equipment manufacturer that is 

responsible for the compliance of the running loss and/or diffusion control requirements should 

simply include the fuel cap information within their certification documentation. Under any 

scenario, OPEI commented that EPA should not require fuel tanks to be tested and certified with 

a fuel cap. EMA commented that, if the final regulation does include a fuel tank cap certification 

and compliance requirement, compliance with such requirement should be the responsibility of 

the entity that is responsible for compliance with the running loss and/or diffusion control 

requirements. 

Letters: 

Commenter Document # 

OPEI 0675 

Briggs and Stratton 0657 

EMA 0691 

Our Response: 

We consider the fuel cap, when directly mounted on the fuel tank, to be part of the fuel 

tank. The fuel cap will therefore be included in the tank permeation standard and test. We 

understand that a given fuel cap may be used in several tank designs. In addition, the fuel cap 

may be constructed by a different manufacturer than the fuel tank. Therefore, we have included 

certification testing flexibility that will allow manufacturers to determine the best approach, for 

their individual business situations, to certifying their tanks and fuel caps to the permeation 

standard. These alternatives to testing the fuel tank with the cap in-place are listed below. 

•The fuel cap manufacturers may test their caps and certify them separately to a separate 1.5 

g/m2

/day cap permeation standard. In this case, the fuel tank could be certified separately 

with a sealed opening, similar to the California ARB testing. 

•Manufacturers may, optionally, test the cap separately from the tank and combine the results 

to determine the total tank permeation rate. This option would allow for fuel caps that do 

not meet the 1.5 g/m2

/day standard, but would still make up a small enough part of the tank 

surface area such that the tank/cap combination would still comply with the permeation 

standard. 

•The manufacturer may also opt to use a default permeation rate of 30 g/m2/day. To be 

eligible for this default rate, the seal on the fuel cap must be made of a low-permeation 

material, such as a fluoroelastomer. The surface area associated with this default value is 

the cross sectional area of the opening that is sealed by the fuel cap. If this default value 

were used, the fuel fill would be sealed with a non-permeable plug during the tank 

permeation test, and the default permeation rate would be factored into the final result. 

4-14
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.2.7 Running loss control 

What Commenters Said: 

The California Air Resources Boards supported control of running loss emissions from 

Small SI equipment, but recommended setting performance standards. 

 Environmental Defense expressed support for the proposed design-based approach to 

reduce running loss emissions from small engines. One of the options available to manufactures 

is the use of carbon canisters which are in use in California today. However, they urged EPA to 

adopt more immediate implementation dates. Environmental Defense argued that the proposal 

provides manufacturers ample flexibility in complying with the running loss standard as they 

may choose from four different design approaches and that this choice to utilize any of a range of 

evaporative control designs militates in favor of near-term implementation dates. 

In contrast, EMA and OPEI commented that the running loss control requirement should 

be implemented at the same time as both the evaporative permeation control requirements and 

the exhaust emission requirements for nonhandheld equipment. OPEI commented that 

implementation of even the most basic running loss system would require a significant 

investment in terms of development and tooling. OPEI argued that EPA should not impose such 

requirements without adequate substantiation of effectiveness, function and safety. OPEI 

commented that EPA performed very little practical testing with running loss systems in place. 

In addition, OPEI stated that the significant challenges related to safety and function associated 

with these new control techniques (such as increased fuel tank pressure) are not addressed in the 

proposed rule’s preamble or Impact Analysis. Running an engine or piece of equipment in a lab 

is very different from actual use conditions and OPEI contends that EPA has not adequately 

considered the costs and challenges associated with the proposed modifications. 

OPEI further commented that the proposed rule specifically states that an actively purged 

canister would qualify as a means to reduce running loss; however, CARB has data that 

demonstrates that a passively purged canister also provides effective running loss control. EMA 

and OPEI requested that EPA broadly accept any system that utilizes an HC adsorption media in 

the fuel tank vent system as an acceptable running loss control system. EMA and OPEI also 

requested that products that meet the California ARB Tier 3 diurnal and running loss 

requirements automatically be deemed compliant with EPA’s Phase 3 running loss regulations. 

EMA commented that the proposed ability to demonstrate running loss control by 

compliance with the 8°C temperature rise requirement was based on very limited testing. EMA 

recommended increasing the maximum temperature rise to 10°C to meet the running loss 

requirement. EMA commented that the fuel tank bladder running loss control method lacks 

sufficient definition to meet the requirements of a clear and evenly applied standard and that 

additional refinement of this option is necessary. EMA also noted that options to control running 

loss through increased fuel tank pressures could be viable in some cases; however, they 

expressed concern that a large number of fuel tanks cannot utilize increased tank pressure as a 

control technology exclusively. As an example, EMA stated that many Small SI fuel tanks will 

change shape significantly at internal pressures less than 7 kPa resulting in fuel tank interference 

with moving parts in proximity of the tank. 

4-15 
Chapter 4: Evaporative Emissions 

OPEI commented that no running loss emissions standards are needed for handheld 

equipment. OPEI stated that, due to space, multi-position use, and weight constraints, the 

application of carbon canisters or other measures to reduce running losses from handheld 

equipment are not feasible. 

Letters: 

Commenter Document # 

OPEI 0675 

Environmental Defense 0648 

California ARB 0682 

EMA 0691 

Our Response: 

We are establishing standards to control running loss emissions from nonhandheld Small 

SI equipment beginning in the same year as the Phase 3 exhaust emission standards—2012 for 

Class I engines and 2011 for Class II engines. Because the running loss control technology is 

integral to the fuel system, we believe it is appropriate to implement these standards in the same 

year as for the fuel tank permeation requirements. This will help minimize costs in that 

manufacturers will be able to transition to a single new fuel system design. 

We have measured fuel temperatures from several Small SI equipment types and found 

that, in most cases, significant fuel heating occurred during engine operation. Emission tests 

were then performed on fuel tanks for this equipment by heating the fuel to the same temperature 

profile as was observed in-use. This testing, which is described in more detail in the RIA, 

support our finding that running loss emissions from Small SI equipment are significant. 

There are several different design approaches that will reliably and effectively control 

running losses. However, it is very difficult to define a measurement procedure to consistently 

and accurately quantify running losses. Also, a performance standard with such a procedure 

introduces a challenging testing requirement for hundreds of small-volume equipment 

manufacturers. Moreover, we believe that the design approaches are straight-forward and can be 

clearly described and easily installed. We are therefore not controlling running losses using the 

conventional approach of establishing a procedure to measure running losses and adopting a 

corresponding emission standard. Manufacturers can choose from one of the following 

approaches to meet this requirement: 

• Vent running loss fuel vapors from the fuel tank to the engine’s intake manifold in a way that 

burns the fuel vapors in the engine instead of venting them to the atmosphere. The use of an 

actively purged carbon canister will qualify under this approach. 

• Use a sealed fuel tank. A fuel bladder could be used to minimize fuel vapor volume in a 

sealed fuel tank without increasing tank pressure. 

• Use a system with an approved executive order from the California Air Resources Board. An 

example of this would be a design in which a fuel cap is fitted with a small carbon canister 

and mounted on a tank that is not exposed to excessive engine heat. 

4-16
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

With regard to bladder fuel tanks, this is offered only as one suggestion of a technology 

that could be used in conjunction with a sealed fuel tank as a strategy for minimizing pressure 

buildup in the tank. In a bladder fuel tank, the bladder collapses around the fuel, preventing the 

formation of fuel vapor and the associated pressure increase. Because this is simply an example 

of a technology that could be used with a sealed fuel tank, we do not believe that it is necessary 

to describe this technology in the regulations as suggested by EMA. 

In the NPRM, we proposed another running loss design option whereby manufacturers 

could demonstrate, through testing, that the fuel temperature in the tank does not increase by 

more than 8°C during normal operation. Manufacturers commented that the temperature testing 

associated with this design option was too complex, the temperature limit was too low, and the 

associated diffusion requirements were infeasible. In later conversations, industry stated that 

they would not use the temperature design option, largely due to the complexity of the associated 

diffusion standards that would be necessary; therefore, we are not finalizing this option. 

We are not applying the running loss requirements to handheld Small SI engines. We 

believe running loss emission standards should not apply to handheld engines at this time 

because the likely approach to controlling running losses could require that manufacturers revisit 

their design for controlling exhaust emissions. As described above, we are not changing the 

exhaust emission standards for handheld engines in this rulemaking. In addition, there are some 

technical challenges that will require further investigation. For example, the compact nature of 

the equipment makes it harder to isolate the fuel tank from the engine and the multi-positional 

nature of the operation may prevent a reliable means of venting fuel vapors into the intake 

manifold while the engine is running. 

4.2.8 Diffusion 

What Commenters Said:

 Environmental Defense expressed support for standards to reduce diffusion emissions, 

stating that both performance and design based standards are effective in controlling evaporative 

emissions. However, they stated that implementation date for the diffusion standard was delayed 

to far into the future. 

EMA, OPEI, and Briggs & Stratton commented that they do not support the inclusion of 

diffusion emission control in the final rulemaking. They argued that the testing performed to 

date over-estimates the diffusion emission contribution to total evaporative emissions, and that if 

tested in a manner more representative of the real in-use environment, it is unlikely that the 

diffusive emissions would be significant enough to warrant control. EMA offered the following 

specific comments on the diffusion testing performed by EPA: The conditions in the SHED 

enclosure are not representative of in-use conditions. Specifically, the air motion necessary to 

ensure good mixing and temperature control in the SHED enclosure causes higher emissions 

than actual in-use conditions. Most small engine equipment is stored in a quiescent atmosphere 

(shed or garage) in which concentration gradients are static and rarely disturbed. In a SHED 

enclosure, the required air motion disturbs the concentration gradient and amplifies the diffusive 

forces. Additionally, small variations in SHED enclosure temperature inherent to the 

temperature control systems will cause a diurnal action in the tank as the tank vapor space 

4-17 
Chapter 4: Evaporative Emissions 

temperature changes. This cyclic temperature variation does not commonly occur in normal 

small engine storage. It is an artifact of the test method that tends to increase the measured 

emissions, but is not indicative of a true diffusion process. While the high fuel fill level in the 

proposed test method was included to counteract this diurnal effect, no testing was actually 

performed to determine if the fill level requirement had a significant effect on reducing the 

influence of the temperature fluctuation. 

EMA, OPEI and Briggs & Stratton also argued that there is very little data to support the 

technical feasibility or impact of the 0.8 g/day requirement because the testing was performed on 

a small subset of fuel system configurations that did not adequately address the breadth of 

product variables or the inherent test-to-test variation. EMA and OPEI commented that, in the 

event diffusion is demonstrated to be a significant emissions factor, additional study is needed to 

develop reasonable requirements. If there is a need to control diffusion emissions independently, 

EMA and OPEI commented that a design standard approach would be more appropriate as 

quantification of diffusion emissions through a prescriptive test method would not significantly 

enhance the emission inventory reduction associated with the implementation of the regulation, 

but would significantly increase the cost of compliance. 

Further, EMA and OPEI commented that the proposed control of running losses will 

substantially control the diffusion emissions and thereby making separate diffusion control 

requirements redundant and unnecessary. They recommended that EPA recognize the 

interaction between running loss control and diffusion control in either regulatory or preamble 

language in order to assure that actively controlled running loss systems, including those 

approved by the California ARB certification process, will provide sufficient diffusion control 

without requiring further demonstration. 

OPEI also commented that the caps and tanks for handheld products should be exempt 

from the diffusion control requirements. Due to space, multi-position use, and weight 

constraints, OPEI argued that the application of carbon canisters or other measures to handheld 

products are not feasible, and that handheld engines and equipment already have a form of 

diffusion control since fuel tanks have no direct uncontrolled openings. 

Letters: 

Commenter Document # 

OPEI 0675 

OPEI 0675 

Environmental Defense 0648 

Briggs and Stratton 0657 

EMA 0691 

Our Response: 

We did not propose diffusion standards for handheld equipment. Handheld equipment 

uses fuel caps that are either sealed or have tortuous venting pathways to prevent fuel from 

spilling during operation. We believe these fuel cap designs limit diffusion emissions 

sufficiently so that we do not need to establish a diffusion standard for this equipment. 

4-18 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Similarly, we are not finalizing the proposed diffusion standards for nonhandheld Small 

SI equipment. We believe that the final running loss design standards will effectively control 

diffusion emissions because there will be no direct path for vapor to escape through diffusion. 

Under the proposed running loss standards, one of the design options for running loss emissions 

control was an open vent system with limits on fuel temperature increases during operation. 

Under that option, diffusion emissions could occur through the open vent. However, because 

this temperature-based option for running loss control is not included in the final standards, we 

believe that a separate diffusion standard would be redundant. 

We disagree with the commenter’s assessment of our characterization of diffusion 

emissions or of the testing performed to measure diffusion from Small SI equipment. The fuel 

tanks selected for the Small SI diffusion testing were from four high sales volume lawnmowers, 

representing a large share of Class I equipment sales. Testing was performed both in stock 

configurations and with a vent hose, such as may be expected in equipment with running loss 

emission control. Testing was also performed under variable temperature (diurnal) conditions 

and at constant temperature to quantify temperature effects. The proposed standard was based 

on actual test data, and therefore accounted for any temperature fluctuation or air mixing effects 

that may occur during testing. The results from this testing, which are described in more detail 

in Chapter 5 of the RIA, suggest that some common fuel cap designs result in an order of 

magnitude higher diffusion emissions than other common fuel cap designs. 

4.2.9 Diurnal 

What Commenters Said: 

Several commenters stated that EPA should establish diurnal emission controls for small 

spark-ignition engines, noting that the California Air Resources Board has already done so. 

These commenters included NACAA, MARC AQ Forum, NESCAUM, and the Wisconson 

DNR. In addition, Environmental Defense noted that the California ARB rules provide 

manufacturers with a choice of either certifying to a performance or design standard that utilizes 

carbon canisters. They cited the preamble to the proposed rule in which EPA states that the use 

of passive purging carbon canisters “could reduce diurnal emissions by 50 to 60 percent” while 

active purging could produce even greater reductions. Environmental Defense argued that the 

national standards should be at least as stringent as those adopted by California and therefore 

objected to the omission of a diurnal standard for small engines from the proposed rules. 

The California Air Resources Board recommended that a diurnal performance standard 

be set for the most representative small spark-ignition engines. Without a performance standard, 

California ARB argued that the U.S. EPA cannot validate emission reductions because a designonly standard cannot take into account connector losses, carburetor emissions, and leaks from 

poorly designed integrated engines. They commented that the diurnal standard should measure 

emissions from complete evaporative emission systems, be measured over three days (without a 

carbon canister) or seven days (with a carbon canister), and be based on tank volume, noting that 

his would be consistent with on-road vehicle test procedures. California ARB believes that two 

years is sufficient time for meeting the diurnal emission standards. 

4-19 
Chapter 4: Evaporative Emissions 

EMA and OPEI presented their opinion that the test data generated by EPA during the 

regulatory development process confirmed that Small SI equipment would not provide 

significant benefit from the addition of a diurnal standard requirement. They commented that the 

proposed combination of permeation control and running loss control will provide a significant 

reduction in evaporative emissions from these products, while providing the flexibility for each 

manufacturer to determine the most appropriate means to achieve these controls. 

Letters: 

Commenter Document # 

Wisconsin DNR 0663 

OPEI 0675 

NACAA 0651 

Environmental Defense 0648 

NESCAUM 0641 

MARC AQ Forum 0696 

California ARB 0682 

EMA 0691 

Our Response: 

We did not propose, and are not finalizing, diurnal emission standards for Small SI 

equipment. Compared to other evaporative emission standards we are finalizing in this rule, 

diurnal emission control would be significantly more expensive on a cost per ton basis. This is 

described in more detail in Chapter 11 of the RIA. This cost sensitivity is especially noteworthy 

given the relatively low diurnal emission levels (on a per-equipment basis) from such small fuel 

tanks. However, we will continue to monitor the progress of diurnal emission control systems, 

such as those applied to equipment certified in California. If new designs lead to more cost 

effective control measures, or the environmental need justifies further controls, we will revisit 

this issue in the future. 

Although we are not finalizing diurnal emission standards for Small SI equipment, in 

response to comments received, we are permanently adopting the provision allowing 

manufacturers to use the SHED-based procedures and standards adopted by California ARB for 

nonhandheld Small SI equipment. Under this approach, the evaporative emission test would be 

for the whole equipment rather than based on the component approach to meeting evaporative 

emission standards. Manufacturers expressed an interest in indefinitely preserving the option to 

comply with diurnal emission standards using the SHED test to be able to certify and sell 

products for sale in all 50 states. The SHED-based approach might allow for use of fuel tanks or 

fuel lines that exceed the component standards, but we believe the overall emission control 

(including control of diurnal emissions) will be at least as great from systems that have been 

tested and certified using SHED-based procedures. We have therefore incorporated the 

California ARB SHED procedure by reference and allow for certification using those 

procedures. 

4-20
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.3 Marine SI standards and lead time 

4.3.1 Fuel line permeation standards and lead time 

What Commenters Said: 

ABYC commented that it is publishing an early revision (July 2007, effective July 2008) 

to its gasoline fuel system standard H-24 that includes a provision for low permeation fuel hose. 

Concurrently ABYC has worked with the Society of Automotive Engineers to produce a now 

published standard on qualification testing for the low-permeation hose to meet the rule. 

NMMA commented that January 1, 2009 is the appropriate compliance date for lowpermeation fuel lines. The ABYC recently incorporated low-permeation fuel line requirements 

into the industry guidance document H-24, Gasoline Fuel Systems, and these requirements will 

be effective July 31, 2008. While this document serves as guidance for the industry, compliance 

with H-24 (as well as other ABYC specifications) is a condition of membership for NMMA. 

NMMA commented that the incorporation of the federal requirements into the ABYC document 

and NMMA’s efforts to mandate compliance with those standards will help transition the entire 

marine industry to the use of low-permeation fuel lines. However, NMMA also stated that it will 

take a great deal of outreach on the part of EPA and NMMA to ensure that the recreational 

marine industry is aware of these new requirements and understands how to certify to the 

standards. For these reasons, NMMA commented that he hose standards should not be pulled 

ahead earlier because adequate time for the implementation of low-permeation fuel lines is 

critical to ensure that both engine manufacturers and boat builders are aware of the new 

requirements. 

Sixteen boat builders commented on the implementation date for the marine hose 

permeation standards. In general, they commented that January 2009 would be a reasonable 

implementation date for these standards. Boat builders commented that an earlier date would not 

be feasible because EPA needs to communicate effectively to thousands of small businesses to 

ensure all boat manufacturers become aware of the new requirements for low-permeation fuel 

lines. Although compliance to ABYC H-24 is a condition of membership in NMMA, this only 

affects 400 or so out of 3000 manufacturers of boats in the US. In addition, boat manufacturers 

commented that they will need adequate time to delete their inventory. Boat builders commented 

that they will begin deplete inventory once final rule passed, but they would need 8-12 months 

after the final rule to be 100 percent compliant. Boat builders expressed support of placing the 

responsibility on component vendors to have parts certified to meet emission requirements. 

Lowe Boats commented that, other than for fuel feed hose on pontoon boats powered by 

sterndrive engines, it does not have any experience in certification or testing of low permeation 

fuel systems. Therefore, an implementation date of January 2008 would not be feasible due to a 

lack of training to understand the details of the ruling and time to deplete inventory of existing 

fuel system components. On the other hand, Godfrey commented that it has already switched to 

low permeation hoses. 

4-21 
Chapter 4: Evaporative Emissions 

NMMA provided comment on how a pull-ahead for low-permeation fuel lines would be 

implemented given that the fuel line from the tank to the engine is typically installed by the boat 

builder, while the under-cowl hoses are installed by the engine manufacturer. Two suggestions 

are provided by EPA for implementation: (1) the engine manufacturer could specify lowpermeation fuel line in the installation instructions beginning in 2008; (2) the engine 

manufacturer could refuse to sell engines to boat builders who do not begin using lowpermeation fuel lines in 2008. NMMA stated that, assuming the compliance date is changed 

from 2008 to 2009, the first suggestion is the only approach of the two provided that is at all 

workable for engine manufacturers to accomplish the goal of the pull-ahead. Further, NMMA 

commented that, while including the specification for a low-permeation fuel line in the 

installation instructions will inform the boat builder of the requirements, there is no way for the 

engine manufacturer to control what the boat builder will do with the fuel lines. In recognition of 

this fact, NMMA recommended that EPA should include in the evaporative emissions 

requirements a “safe harbor” similar to that discussed above in the context of the exhaust 

emission standards and the OBD system under the SD/I engine manufacturer section. Under this 

provision, so long as the engine manufacturer includes a specification for low-permeation fuel 

lines, the compliance obligation with the rule would be met. 

 Sierra currently distributes marine fuel hose under the Shields Marine Hose brand name. 

Shields Marine Hose commented that these fuel lines are manufactured by a major rubber hose 

manufacturer who deals in automotive and industrial hose and that all of the major current 

suppliers of marine fuel feed lines are dependent on similar companies for their product. Shields 

commented that that low permeation marine fuel line is currently available from a single vendor 

at this time, but their factory is working on developing a cost competitive low permeation hose. 

Due to the time needed to develop and test new products, and the lack of priority given to marine 

hose by automotive suppliers, Shields commented the compliance date should be January 1, 

2009. Shields stated that this implementation date will allow complete availability of tested 

compliant hoses from all vendors and that the time will be used to allow builders and suppliers to 

balance inventories. Shields further commented that builders will also need this time to make 

sure the less flexible low permeation hose can be routed correctly and to match fittings and hose 

to make sure of adequate coupling retention. 

Trident Rubber and Parker Hannifin commented that there is no compelling reason to 

delay the hose permeation standards beyond the earliest practicable timeline. Low permeation 

"barrier style" marine fuel line hose (now designated and labeled "Type A1-15" as per SAE 

J1527 and ABYC H24 Standards) has been abundantly available, and successfully used on the 

majority of U.S. boats over the past 12 years. Trident stated that its factory records indicate that 

over 43 million feet of this hose has been supplied to the marine industry during this period. So 

there is strong industry awareness of and experience with this hose. Regarding the boat builders 

need to deplete their inventories of non-complaint fuel hose, Trident and Parker commented that 

this is not a problem because the majority of boat builders stock hose inventories of one month 

or less of their usage, and the fuel line hose is sold in quantities as small as 25 feet. Trident and 

Parker commented that it is logical for the EPA to have a compliance date for low permeation 

fuel line hose no later than the July 31, 2008 effective compliance date for ABYC and NMMA. 

Parker commented that guidance is necessary to ensure that the entire recreational marine 

industry is fully aware of these new requirements, but given the vast informational and 

4-22
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

educational vehicles currently available to boat manufacturers such as trade and consumer shows 

and commercial advertising, educating boat manufacturers should not be an issue. 

Attwood commented that it provides fuel hose assemblies, fuel fills, ventilation 

components, tanks, surge protectors and fittings that total well over a hundred different products. 

Attwood commented that an implementation date of January 1, 2008 for fuel hose standards 

would be too soon considering that the EPA will not have a final ruling on the fuel hose 

permeation until just before the January 1, 2008 mandate. Atwood stated that it would need more 

time to understand and react to assure that the final product produced not only adheres to the 

standard but is of the highest quality as well. Aggressive timing may force Attwood, due to 

engineering resource concerns, make a decision that in the face of the high competition in this 

product category that Attwood would be better off dropping out of this product category and 

focus Attwood’s resources on our other categories with much higher returns. 

Honda commented that the implementation date for fuel filler pipe/tube permeation 

standards should be delayed until 2011, or at a minimum two model years of lead time from the 

final rule effective date and should be the same year as for fuel tanks. Referring to Section 

1045.107 (a), a fuel fill pipe that is exposed to liquid fuel is considered to be fuel line according 

to the proposal. Honda argued that, unlike the normal fuel supply line, extra time will be needed 

to modify the fuel tank, design, validate and find a supplier for the larger diameter fill pipe. 

California ARB commented that the fuel line permeation standard of 15 grams per square 

meter per day (g/m2

/day) is the same as those for recreational vehicles and that the California 

small off-road engine/equipment program has implemented this standard since 2006. California 

ARB further commented that its component certification data for fuel hoses supports setting a 

lower standard, and recommended a more stringent standard of 5 g/m2/day at 40 degrees Celsius. 

NMMA: The boat builders start building for their model year in July. If EPA finalizes a 

rule in June or July that requires that low-permeation hose be required starting on January 1, 

2009 it is already too late to build this into their product. It is also going to take quite some time 

before the 2000+ motorized boat builders even know that they need to do this. NMMA would 

recommend that EPA either put some enforcement discretion language in the preamble that 

explains that boat builders be required to begin installing low-permeation fuel hose in 2009 for 

2010 model boats. The materials for 2009 design boats were ordered at the time of the 2007 

IBEX trade show. Orders for 2010 were placed around the time of the 2008 IBEX trade show. 

St. Gobain: A situation has evolved with what could be an excess of a relatively 

expensive raw material near the end of the year when the change-over to a new low-permeation 

fuel hose is required. It involves just one product type for a key OEM customer. Is there a way 

that EPA could accommodate a manufacturer’s need to avoid scrapping unused raw material or 

finished goods such as fuel line? If the tubing has a manufactured date in 2008, can the engine 

builder use it after Jan. 1, 2009? This critical plastic raw material has a high minimum order 

quantity due to the reactor size used to make it. It is a unique material that is only made for us. 

4-23 
Chapter 4: Evaporative Emissions 

Letters: 

Commenter Document # 

NMMA 0688 

Sea Ray 0683 

Honda 0705 

California ARB 0682 

Trident Rubber 0636 

Parker Hannifin 0672 

Attwood 0653 

ABYC (hearing) 0642 

Sea Ray 0683 

S2Yachts 0697 

Grady-White Boats 0677 

North American Sleekcraft 0666 

Triton 0656 

Lund Boat Co 0655 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products 0652 

Lowe Boats 0660 

Godfrey 0645 

American Marine Sports 0639 

Cigarette Racing 0637 

Regal Marine Industry 0635 

Massachusetts Marine Trade Association 0634 

Regulator Marine Inc. 0632 

Chaparral/Robalo Boats 0630 

Ranger Boats 0628 

Premier Marine Inc, 0613 

Hallett 0713 

Skeeter 0706 

Yellowfin 0681 

NMMA 0792 

St. Gobain 0796 

Our Response: 

As proposed, the permeation standard is 15 g/m2

/day for marine fuel lines. This standard 

is supported by test data presented in the Final RIA on low-permeation marine fuel lines. The 

implementation date for this standard is January 1, 2009. This means that any boat, portable fuel 

tank or outboard engine manufactured on or after this date would need to use fuel lines compliant 

with this standard. We allow for production of noncompliant fuel lines to serve as replacement 

parts as described in Section 4.7.10. 

There are two exceptions to the above implementation date. First, as discussed below in 

Section 4.3.3, we are providing additional lead time for under-cowl fuel lines on outboard marine 

4-24
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

engines. Second, we will allow boat builders to use up their existing inventory of fuel lines 

provided under normal business practices, even beyond the standard date. However, 

manufacturers would not be permitted to circumvent the standards by stockpiling noncompliant 

hose just prior to the implementation of the standards. 

Low-permeation marine fuel lines and fill neck hose are already commercially available. 

In fact, many manufacturers already use low-permeation fuel lines on their boats. In addition, 

ABYC recently incorporated low-permeation fuel line requirements into the industry guidance 

document H-24, Gasoline Fuel Systems, and these requirements will be effective July 31, 2008 

and are mandatory for NMMA certification. 

We first proposed these standards in 2002. We reproposed these standards in 2007, with 

the clear understanding that low-permeation was now readily available and would be expected 

for the 2009 model year. The delayed timing of the final rule requires that we specify January 1, 

2009 as the start date rather than the 2009 model year. While we are prepared to accommodate 

existing inventories of fuel lines, we find it highly problematic to learn that manufacturers are 

admitting that they are continuing to order significant quantities of high-permeation fuel line in 

October 2007 and plan to continue to order high-permeation fuel line in October 2008 such that 

they will be unable to comply with standards using normal inventory practices until the 2011 

model year. Based on the information supplied by Trident regarding normal inventory practices, 

we expect that inventories of high-permeation fuel line will generally be depleted within 30 days 

following the effective date of the regulation. Any high-permeation fuel lines installed in vessels 

after this time would be determined to violate the stockpiling prohibition unless the manufacturer 

could demonstrate that unusual circumstances caused the inventory of high-permeation fuel lines 

to exceed a 30-day supply. The circumstances described by St. Gobain would appear to qualify 

for an allowance for extended inventories. Placing routine orders for high-permeation fuel lines 

in 2007 and 2008 in such that inventories of these fuel lines would allow for continued 

production more than 30 days after the effective date of the regulation where low-permeation 

fuel lines were also available would clearly not be an acceptable demonstration in this regard. 

4.3.2 Fuel line permeation- fill neck 

What Commenters Said: 

NMMA expressed concern about including filler necks, under certain conditions, in the 

fuel line definition. NMMA commented that the inclusion of the filler neck in the definition for 

“fuel line” is contrary to their understanding of what is supposed to constitute a fuel line. They 

argued that filler necks are not intended to store fuel, which is further demonstrated by the 

applicable ABYC standards. NMMA stated that evaporative emissions from filler necks are very 

low, and referenced testing performed in 2005 that demonstrates this. Given the characteristics 

of a filler neck and the low evaporative emissions associated with this component, NMMA 

recommended that EPA delete the language in § 1045.801 which says “if any portion of the filler 

neck material continues to be exposed to liquid fuel after a refueling event in which an operator 

fills the tank as full as possible.” 

4-25 
Chapter 4: Evaporative Emissions 

Yamaha provided further explanation on the above concern expressed by NMMA 

regarding the fuel line definition. Yamaha stated that Federal regulations (33CFR Subpart J 

183.501~183.590) and ABYC H24 require marine fuel fill hoses be “self draining” and installed 

at or above the top most portion of the fuel tank. Also H24.5 requires a 5 percent vapor space be 

applied to the tank for compliance for fuel expansion. Yamaha commented that there is no 

available or feasible technology today to prevent a consumer from overfilling a designed system 

on a boat or for current automotive except for education and warnings. Yamaha provides, in the 

Owners Manual, directions for proper filling. These directions state that the owner should not 

fill the fuel fill hose with gasoline and, for PWCs, to stop filling the tank at least 2” (inches) from 

the top surface of the tank. When the engine hatch is open, Yamaha stated that there is a visual 

indication of fill level for their PWCs. Yamaha requested that the last sentence under the 

definition for fuel line be stricken because this is a consumer tampering issue that is 

uncontrollable through boat design. 

Letters: 

Commenter Document # 

NMMA 0688 

Yamaha 0721 

Our Response: 

The purpose of this definition was to include fuel lines exposed to liquid fuel and exclude 

fuel lines exposed only to fuel vapor (or short wettings in the case of fill necks). Data in the RIA 

suggests that vent lines and fuel fill necks generally have relatively low permeation when 

exposed to fuel vapor under normal fuel system configurations. At the same time, data in the 

RIA shows that vent lines and fill neck hose have relatively high permeation when exposed to 

liquid fuel. In the case where a vent line or fuel fill neck stores liquid fuel after a refueling event, 

we believe that these components should be covered by the fuel line permeation standards. For 

this reason, we specifically added a reference to vent lines that fill with fuel after a refueling 

event in the definition of fuel lines. 

We agree with the comment that the definition of fuel lines should not be based on 

operator behavior. Therefore we revised the definition of fuel lines to focus on the design of the 

fuel system rather than operator behavior. In the case where a fuel system is designed such that, 

under a normal fuel filling event, the vent line and fill neck are not exposed to liquid fuel, then 

they would not be considered to be fuel line for the purposes of the permeation standards. For 

example, a fuel system can be designed to work with a fuel shut-off control on the fuel fill nozzle 

such that the nozzle shuts off before the tank completely fills. This would provide the vapor 

space specified in ABYC H24 and prevent the vent line and fill neck from storing fuel. We 

would not consider the vent line and fill neck to be subject to the permeation standards in this 

design. We recognize that, under this design, an operator could fill the tank higher by repeatedly 

restarting the fuel pump after it shuts off. In this case, we would expect the manufacturer 

supplied directions for proper filling to state that the owner should not restart the pump after 

automatic shut off. 

4-26
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.3.3 Fuel line permeation– under-cowl fuel lines 

What Commenters Said: 

Several manufacturers commented that additional lead time would be necessary for fuel 

lines used under the cowl on outboard marine engines. These manufacturers included NMMA, 

Mercury, Suzuki, Yamaha, Honda, Sea Ray, American Marine Sports, Cigarette Racing, 

Yellowfin, Parker-Hannifin, and Trident Rubber. 

Manufacturers commented that, despite the fact that low-permeation hoses are 

commercially available, a major concern for OB engine manufacturers is the ability to meet the 

requirement to use low permeation hoses under the engine cowl, on outboard engines, by 2009. 

These smaller hose sections between the engine mounted fuel-system components and 

connectors are preformed or injection- molded. Manufacturers insisted that a model year 2009 

compliance date for these under-cowl hoses is simply not feasible given that hundreds of hose 

parts will have to be redesigned and manufactured and stated that the alternative proposal in the 

preamble to allow the under-cowl hoses additional time for compliance is therefore necessary 

and appropriate. NMMA and Mercury expressed support for the concept of EPA’s optional 

approach for implementation that would allow under-cowl hoses delayed implementation in 

exchange for an earlier compliance date for low-permeation fuel line from the fuel tank to the 

engine. However, given that the promulgation of the final rule will not occur until the end of this 

year at the earliest, NMMA and Mercury recommended that EPA finalize a revised schedule that 

would account for the one year delay. Using EPA’s proposed approach, the revised schedule 

would be January 1, 2009 for implementation of low-permeation fuel lines and a phase-in of 30-

60-90 percent for under-cowl hoses between model year 2010 and 2012 and 100 percent 

compliance in model year 2015. This phase-in schedule was also specifically supported by 

Suzuki, Yamaha, and Honda 

Suzuki recommended a single year averaging approach is appropriate for compliance 

under the proposed phase-in concept. This would consist of calculating the total interior surface 

area of the under-cowl fuel line installed on each model variation in a manufacturer's full product 

line, determining the total hose surface area from projected sales by engine family and model, 

and implementing complaint hose as necessary for a given model year and phase-in percentage. 

Under this approach, the manufacturer would have the flexibility to select which fuel lines can 

most appropriately be revised in a cost-effective manner while ensuring overall compliance with 

the standards. 

4-27 
Chapter 4: Evaporative Emissions 

Letters: 

Commenter Document # 

NMMA 0688 

Yamaha 0721 

Mercury 0693 

Suzuki 0698 

Trident Rubber 0636 

Parker Hannifin 0672 

Yamaha (hearing) 0642 

Sea Ray 0683 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products 0652 

American Marine Sports 0639 

Cigarette Racing 0637 

Yellowfin 0681 

Our Response: 

Outboard engine manufacturers have expressed concern that it will be difficult for them 

to meet final 2009 date for the sections of fuel lines that are mounted on their engines under the 

engine cowl. While some sections of straight-run fuel line are used on the outboards, many of 

the smaller sections between engine mounted fuel-system components and connectors are 

preformed or even injection-molded parts. Outboard engine manufacturers stated that they will 

need additional time to redesign and perform testing on low-permeation fuel lines under the 

cowl. To address this issue, we are finalizing a phase-in of under cowl fuel line permeation 

standards. For each engine, we are adopting a phase-in, by hose length, of 30 percent in 2010, 

60 percent in 2011, 90 percent in 2012-2014 and 100 percent in 2015 and later. This will allow 

manufacturers to transition to the use of low-permeation fuel lines in an orderly fashion. 

In the NPRM, we asked for comment on an optional program whereby manufacturers 

would have to offset this delay in hose permeation control by pulling ahead straight-run fuel 

lines exterior to the cowl. We are not finalizing this phase-in as being dependent on a pull ahead 

of straight-fuel lines for two reasons. First, the implementation would be difficult given that the 

outboard engine manufacturer installs the under cowl fuel lines, while, in most cases, the boat 

builder installs the straight-run fuel lines from the engine to the fuel tank. Second, given the 

timing of the final rule, there is little opportunity for pulling ahead the use of low permeation fuel 

lines. 

In the NPRM, we also discussed basing the phase-in on a per-engine basis or a permanufacturer basis. Suzuki commented that the phase-in be calculated across the manufacturer’s 

full product line based on inside surface area of the under cowl fuel lines. We believe that this 

approach is overly complex for this transitional program. Instead, we are basing the phase-in on 

length of the fuel lines for each engine. By using this approach, it removes the need to establish 

a credit trading program between engine models and greatly simplifies implementation of this 

program. 

4-28
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.3.4 Fuel line permeation– primer bulbs 

What Commenters Said: 

Several manufacturers commented that additional lead time would be necessary for 

primer bulbs. NMMA, Mercury, Suzuki, Yamaha, Trident Rubber, Shields Marine Hose, Parker 

Hannifin, Attwood, Sea Ray, Grady-White, Triton, Brunswick Corporation, Lowe Boats, 

Godfrey, Regulator Marine. NMMA commented that, for small business boat builders that are 

unfamiliar with the certification process, certifying a bulb as part of the fuel system will be 

difficult. 

Manufacturers stated that the implementation date for the proposed permeation standard 

for fuel lines in causes concern for OB manufacturers in the context of the primer bulbs. 

Manufacturers argued that there are currently no low-permeation primer bulbs available in the 

marketplace. To require low-permeation primer bulbs in model year 2009 would mean that this 

product would have to be available next year. Manufacturers insisted that this compliance 

deadline will be impossible for industry to meet given that manufacturers would have to design, 

test and produce the requisite product by next year. In light of the lack of a compliant product, 

several manufacturers recommended a model year 2011 compliance date for primer bulbs. 

NMMA stated that this date would give industry a two-year lead time from the date the rule is 

finalized, which should provide industry with enough time to develop primer bulbs that can meet 

the EPA standards. Other manufacturers, stating similar reasons, recommended an 

implementation date of 2010 for primer bulbs. 

Yamaha commented that it has been researching various materials for permeation 

compliance and to increase the ability of a primer bulb to withstand federal fire test standards for 

under deck installation. Yamaha stated that its testing has shown that current fluorination 

processes to NBR material (FKM product) produces some desired effects however low 

temperature operation is greatly diminished when temps fall at around 20°F. Since a primer bulb 

is used in a very diverse market, Yamaha commented that this current technology may have its 

place but unfortunately use and durability in the colder climates are jeopardized. Yamaha stated 

that it will continue testing to achieve a balance in both use and durability and permeation 

compliance. Suzuki commented that it has already identified some promising materials and 

designs; however it is too early to know if these materials will actually function as desired. 

Assuming that a suitable material is identified, Suzuki stated that the primer bulb will still need 

to be designed, validated and produced in quantity. It is expected that this process will take a 

minimum of two years to complete. Yamaha and Suzuki recommended that EPA revise the 

effective date for implementation of low-permeation primer bulbs until the 2011 model year, 

which will allow a minimal two years of lead-time to develop the appropriate new products. 

Sierra Marine hose stated that it currently manufacturers primer bulbs and primer bulb 

assemblies for the marine industry. Sierra stated that permeation resistant compounds such as 

FKM are available to make low permeation primer bulbs; however, permeation is not the only 

criteria needed to produce usable safe fuel primer bulbs. Primer bulbs must also be ultraviolet 

light resistant, have high shear strength and be abrasion resistant. The material must also remain 

flexible over a wide temperature range. Studies must be run to examine swell, heat ageing and 

4-29 
Chapter 4: Evaporative Emissions 

coupling retention. Sierra stated that it needs to have time to do all of the testing and possibly 

need to build new tooling or purchase new production equipment. In addition to the above, Sierra 

commented that a non-fire retardant SAE J 1527 hose needs to be developed as none currently 

are available. The complete hose assemblies then must be tested for all of the above criteria. 

Sierra must also develop new production lines to assemble the bulbs and fuel line assemblies. 

New packaging will also be required. 

Atwood commented that there is not a primer bulb on the market which will meet EPA’s 

current proposal. Again, the engineering time associated with the development of a “white 

space” product is somewhat lengthy due to the fact that possible new materials and/or 

manufacturing processes may be required to meet the constraints of the new ruling. Atwood 

state that its current endeavors in the design and possible manufacturing of a new primer bulb to 

meet the requirements of the ruling is more on track for the 2010 timeframe. Even then, Atwood 

expressed concern that there are a lot of unknowns that could delay a new primer bulb 

introduction. 

Mercury commented that some small outboards utilize an engine mounted, push primer 

such as those that were excluded from evaporative emissions standards for small nonroad 

engines. Mercury stated that it is appropriate to also exclude them on small outboard engines as 

well because the evaporative emissions from these primers would be extremely small, have not 

been quantified, and there is no development work done to date as to whether there is a need or a 

technology to reduce permeation from these components. 

Letters: 

Commenter Document # 

NMMA 0688 

Sea Ray 0683 

Yamaha 0721 

Mercury 0693 

Trident Rubber 0636 

Shields Marine Hose 0624 

Attwood 0653 

NMMA (hearing) 0642 

Sea Ray 0697 

Grady-White Boats Inc. 0677 

Triton 0656 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products 0652 

Lowe Boats 0660 

Godfrey 0645 

Regulator Marine Inc 0632 

Our Response: 

At the time of the proposal, we agreed that low permeation marine primer bulbs were not 

commercially available. However, we also stated our belief that low permeation fuel line 

4-30 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

materials were available and could be used for manufacturing primer bulbs. In the proposal, we 

specifically identified FKM, which is an elastomer that has long been used in fuel line 

applications. Many grades are available that range in permeation resistance, cold weather 

properties, and flexibility. We recognized that some development time would be necessary to 

develop primer bulbs of this (or other) low permeation fuel materials. 

Since the NPRM, we have received information supporting the proposed position; a new 

primer assembly has been developed that meets the fuel line permeation standards. This 

assembly uses a spring loaded piston as the pumping device rather than depending on the 

flexibility of the housing material. In appearance, it is similar to existing primer bulbs. This 

product is not yet commercially available, but serves as an example of how technology 

progresses, given sufficient incentive and time. 

We agree with manufacturers that additional lead time is necessary to design, validate, 

and produce low permeation primer bulbs. Therefore, we are finalizing an implementation date 

of 2011 for primer bulbs. Mercury commented that engine mounted, push primers are not 

included in the fuel line definition for Small SI equipment and should not be included for marine 

products as well. We excluded these primers for Small SI engines because fuel drains from them 

after priming and they are not usually exposed to liquid fuel. We agree with Mercury that these 

primers should be excluded from the fuel line definition for marine products as well. 

4.3.5 Tank permeation standards and lead time 

What Commenters Said: 

Environmental Defense stated that it is pleased that EPA has chosen to adopt fuel tank 

standards for SI small and marine engines. The California Air Resources Board expressed 

support of fuel tank permeation standards but stated that the standard of 1.5 g/m2

/day should be 

based on testing on CE10 at 40°C rather than at 28°C. California ARB commented that 

component certification data from the small off-road engine program in California supports 

setting a lower standard. California ARB also commented that the phased-in schedule to meet 

the fuel tank permeation standards is too lengthy and that two years is sufficient time to allow 

manufacturers to design and produce equipment meeting the new evaporative standards. 

California ARB pointed out that the control technology is readily available and currently used in 

lawn and garden equipment in California. 

Trident Rubber commented that more time is necessary for development and availability 

of compliant fuel tanks but the early use of low permeation fuel line hose and vent line hoses will 

provide evaporative emissions reductions that can enable time extensions for fuel tanks. 

NMMA stated that it can support the requirement for low permeation plastic fuel tanks, 

with the reservation that any new technology can meet marine durability standards. NMMA 

commented that it does not dispute that the level of the standard is feasible and the 

implementation date for PWCs and portable tanks is achievable; however, NMMA expressed 

concern that the implementation date for SD/I and larger OB fuel tanks is overly ambitious. 

NMMA asserted that trials run by tank manufacturers using multi-layer construction technology 

4-31 
Chapter 4: Evaporative Emissions 

have indicated the following problems: inconsistent impact strength, fitting leaks, processing 

difficulties, tank brittleness, and inability to repeat processing to provide adequate and uniform 

second layer construction. Based on concerns that there are no commercially available 

rotational-molded tanks that could meet the proposed standards and that additional testing and 

trials must be conducted, NMMA stated that it has serious reservations about imposing a 2012 

compliance deadline for rotational-molded tanks. To address these concerns, NMMA 

recommended that EPA perform a technical review in 2010 and impose an implementation date 

based on the findings. 

Brunswick commented that the advent of cross linked polyethylene tanks offered boat 

builders with an alternative material to ensure tank longevity. Brunswick stated that the current 

permeation requirements still have not yielded a commercially viable solution other than a whole 

scale return to aluminum. Brunswick expressed concern that, while many larger tanks are still 

made of aluminum, the increase in bio fuels will bring about larger water content in the fuel 

tanks based on the known properties of ethanol and that increased water brings corrosion 

concerns that we must deal with. Brunswick recommended that we consider a standard for tanks 

similar to that of fuel hoses in order to explore these issues. 

Inca commented that when cross-link polyethylene was first introduced into the marine 

market, fuel tanks began failing in the field and resulted in a national recall and all the tanks had 

to be removed out of the boats. Inca stated that it pioneered the first successful plastic fuel tank 

by researching, redeveloping, and building on the mistakes the first manufacturer made. Inca 

commented that, even then, the plastic tanks were phased in slowly to provide field experience to 

gain confidence and make any necessary adjustments. Inca stated that a similar process is 

necessary for the implementation of low permeation marine fuel tanks. 

Inca argued that the many experimental products and processes used to manufacture lowpermeation tanks have not demonstrated the characteristics needed to consistently manufacture 

fuel containment products with the confidence that is needed to avoid fuel spillage and insure 

safety to users of marine vessels and other original equipment products. Inca stated that it has 

had extensive material trial experiences with Arkema, Exxon/Cyclics, Ticona, Solvay, FluroSeal, and A. Schulman. Inca reported problems they have encountered which included: fitting 

leaks, holes, brittleness, repeatability (high scrap rates up to 75%), constant reformulations in 

materials, machinery modification issues that require untested maintenance practices, premature 

second layer kick off resulting in commingled layers, difficult process changes that are not 

realistic in a major production setting, and bulk storage problems of the second layer materials. 

Due to these kinds of problems, the Inca concluded that the industry does not have a 

commercially proven product (raw material) that will enable them to manufacture roto-molded 

Marine fuel tanks to 1.5 g/m2

/day. 

Inca made several recommendations for what is needed before they will be able to 

produce low-permeation marine fuel tanks. They stated that material suppliers need to continue 

refining their materials. Inca claimed that no materials are commercially available or readily 

processable, although some have passed California ARB requirements. Inca stated that more 

time for internal testing to see that the multi-layer materials hold up to the demanding areas of 

the process variables, mold variables, and design variables that Inca works with day in and day 

4-32
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

out. Inca stated that it needs more external testing data on multi-layer tank models from outside 

labs on mechanical strength tests that are required by H-24. Inca commented that it takes time 

and cumulative experience and knowledge to get it right. Finally, Inca stated that it needs marine 

field testing data and a phase-in period to limit the number of new tanks going into the field in 

order to contain its risks of unexpected performance issues that may arise from uncharted waters 

of rotation-molded multi-layer fuel containment. Due to these concerns, Inca recommended that 

EPA perform a technical review in 2010. 

Promens commented that some barrier layer materials may increase the brittleness of 

plastic marine fuel tanks, thus lowering the impact needed to create a ductile failure of the tank 

shell. Promens performed dart impact testing on one low permeation barrier approach and saw 

that the effect of the peculiar barrier layer causes significant flexibility changes in the cross link 

polyethylene shell, lowering its impact resistance. Promens commented that we should not 

degrade personal safety for environmental benefits and that impacts to the tank such as 

mishandling, poor transportation, manufacturing accidents, or in-field use should not result in a 

lower expectation of performance. 

Grady White requested that EPA withdraw 2012 implementation date, revisit the 

technology in 2010, and set an implementation date at that time. Grady White commented that 

time is needed to develop, test, and field prove new technologies and that the proposed 

implementation schedule is too aggressive considering there are no permanently installed, fieldproven, low permeation tanks currently in-use. Grady White stated that a number of issues have 

been communicated from tank molders including ability to warrant barrier layer, lack of field 

experience, impact resistance, processing expense, and processing control. 

Arkema commented that it supplies PetroSeal technology and is eager to work with tank 

manufacturers to help them meet the tank permeation standards. This technology is a two-layer 

fuel tank. The inner layer is Rilsan Polamide 11, which is an engineered polymer which may be 

used to create a permeation barrier in rotation-molded fuel tanks. Arkema stated that this 

specialty nylon, which is used in automotive fuel lines, gives excellent resistance to fuel 

permeation, and is a tough, impact-resistant polymer. Arkema commented that this material is 

dimensionally stable, molds very easily and is manufactured from a renewable resource (100 

percent bio based from a vegetable oil). In a low-permeation, roto-molded fuel tank, the the 

outer side of the layer is metallized polyethylene which has an excellent resistance to alcohol 

permeation and molds very easily. The inner layer is the PA11 which is designed to adhere with 

the outer layer to ensure the structural integrity of the tank and to ensure minimal permeation. 

As a result, Arkema concludes that tanks manufactured with PetroSeal are very low permeation, 

very tough and cost-effective. 

Arkema commented that the PetroSeal technology meets current EPA permeation 

regulations as tested by EPA laboratories (see the RIA) and has received a California ARB 

exemption for the small off road and recreational vehicle tanks. Arkema also stated that the 

tanks using this construction have been demonstrated to meet US Coast Guard requirements for 

mechanical strength and fire resistance for permanently installed marine fueled tanks. Arkema 

had a ten gallon and 40 gallon fuel tank manufactured and tested by Imanna labs. In addition, a 

lawn and garden fuel tank using this technology passed the SAE J288 snowmobile impact test. 

4-33 
Chapter 4: Evaporative Emissions 

Arkema commented that PetroSeal is a commercially active technology today and they are 

selling this material for use in motorcycle fuel tanks. 

Solar Plastics commented that they have conducted an active research and development 

effort for many years and that numerous tooling, material, and processing concepts have been 

invented, evaluated, or optimized in their test facility. Solar has been working with Arkema and 

now produces multi-layer rotation-molded fuel tanks. Solar Plastics commented that it has 

established safe, reliable, and consistent processes to mold the two layer PetroSeal material 

system. Solar asserted that these molded tanks exhibit excellent adhesion between layers, impact 

strength that meets various industry standards, and permeation resistance well within proposed 

standards. PetroSeal fuel tanks molded by Solar Plastics satisfy durability requirements adopted 

by the marine, and lawn and garden equipment industries. These include ambient and cold 

temperature impacts, and burn tests. Molding methods are cost efficient, and utilize the same 

tooling and machinery that produce single layer tanks. Based on these considerations, Solar 

Plastics concluded that technology is available today to rotation-mold fuel tanks that meet the 

proposed evaporative emissions standards. 

Centro commented that, in anticipation of low permeation requirements for fuel tanks for 

Small SI equipment and for boats, they have worked hard over the last five years to develop a 

solution that meets all requirements. Centro stated that they have a solution that is as durable as 

current rotation-molded tanks and meets all other criteria. Centro commented that they have 

invested hundreds of thousands of dollars in successfully developing and testing this technology, 

and that it would be a disservice to the environment to delay tank permeation standards. 

Briggs and Stratton and EMA commented that the proposed alternative fuel tank standard 

of 2.5 g/m2

/day standard at 40°C is not supported by theory or literature to be equivalent to the 

1.5 g/m2/day standard at 25°C. They stated that the alternative standard should be changed to 3.0 

g/m2

/day at 40°C. California ARB commented that the alternative of 2.5 g/m2/day at 40°C 

suggested by U.S. EPA should not be an option because this standard is too lenient based on 

certification data which supports a tougher standard. 

4-34
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

Environmental Defense 0648 

California ARB 0682 

Trident Rubber 0636 

Inca Molded Products 0700 

Briggs and Stratton 0657 

Brunswick (hearing) 0642 

Grady-White Boats 0677 

Arkema (hearing) 0642 

Solar Plastics (hearing) 0642 

Inca Molded Products (hearing) 0642 

Promens (hearing) 0642 

EMA 0691 

Centro 0737 

Our Response: 

During the development of the proposed rule, we worked closely with the recreational 

marine fuel tank industry to understand their products, business practices, and production 

processes. Information gathered from these interactions was used to craft the proposed 

regulatory provisions related to controlling gasoline fuel tank permeation emissions. During 

these discussions, important issues were identified with respect to concerns regarding the 

technical feasibility of controlling permeation emissions from the cross-link polyethylene 

(XLPE) rotation-molded tanks. 

Manufacturers assert that the availability of rotation-molded fuel tanks is critical to the 

marine industry. This type of fuel tank is installed in many recreational marine vessels powered 

by SD/I and outboard engines. The rotational molding process, which has low capital costs 

relative to injection molding, facilitates the economical production of fuel tanks in the low 

production volumes as required by boat builders. Furthermore, plastic fuel tanks offer 

advantages over metal fuel tanks, both in terms of cost and corrosion resistance. The advantages 

of XLPE over other plastics used in fuel tanks today such as HDPE are its compatibility with the 

rotational molding process and the ability of XLPE fuel tanks to meet the U.S. Coast Guard 

safety tests, especially the flame resistance test. 

We have concluded that the 2012 fuel permeation standards are technologically feasible 

and appropriate for rotation-molded marine fuel tanks. This conclusion is supported by data 

presented in the Regulatory Impact Analysis from comments submitted by two fuel tank 

manufacturers after the proposal. Since we initially proposed tank permeation standards for 

marine fuel tanks in 2002, several manufacturers have shown progress in the development of low 

permeation, rotation-molded tanks. In addition, this rule provides about 36 months of lead time 

for rotation-molded tank manufacturers to address remaining technology issues and to certify 

their products. 

4-35 
Chapter 4: Evaporative Emissions 

However, commenters expressed a concern that some rotation-molded tank 

manufacturers are not as far along in their technological progress toward meeting the standards 

and are not certain about their ability to meet the EPA requirements in 2012. To address this 

situation, these manufactures have requested that EPA perform a technical review in 2010 to 

determine whether the compliance dates should be adjusted. However, we believe that the tank 

permeation standards have been demonstrated to be technologically feasible in the 2012 time 

frame. The RIA identifies several technologies that could be used to reduce emissions from 

rotation-molded tank including barrier materials and post processing coatings. In addition, 

alternative construction methods may be used such as low-permeation fiberglass. Finally, if the 

boat building industry were to accept standardized fuel tank sizes, fuel tank manufacturers may 

be able to make use of higher production volume, low permeation, manufacturing processes such 

as coextrusion blow-molding. Therefore, we do not believe that a technology review of the 

permeation standard is necessary or appropriate. 

Nevertheless, we are concerned about the potential long-term impacts on the small 

businesses that have not yet developed technology that meets the requirements. Although marine 

fuel tanks must comply with Coast Guard safety regulations, marine fuel tank manufacturers 

have never been required to certify to permeation standards. The rotation-molded tank 

manufacturers are generally small businesses who have limited engineering staffs and are 

dependent on materials suppliers for their raw materials. 

During the next few years, EPA intends to hold periodic progress reviews with small 

businesses that manufacture rotation-mold fuel tanks. The purpose of these progress reviews 

will be to monitor the progress of individual companies towards compliance with the tank 

permeation standards and to provide feedback as needed. Rather than conducting a broad 

program with the entire industry, we will conduct separate, voluntary reviews with each 

interested company. These sessions will be instrumental to EPA in following the progress for 

these companies and assessing their efforts and potential problems. 

To help address small-business concerns, we are relying on the hardship relief provisions 

for small-volume manufacturers in 40 CFR 1068.250. In the event that a small-volume 

manufacturer is unsuccessful in the 2012 model year and seeks hardship relief, these progress 

reviews would provide an important foundation in determining whether a manufacturer has taken 

all steps to comply with the permeation standards in a timely and orderly manner. 

We are finalizing the optional alternative standard of 2.5 g/m2

/day at 40°C as proposed. 

This alternative standard is intended to provide flexibility to manufacturers that wish to perform 

a single permeation for certification to EPA standards and for use in certifying to the California 

ARB Small SI standards. The intent of the higher limit of 2.5 g/m2

/day is to account for 

increased permeation rates at elevated temperature. This increased limit is not intended to 

represent how an average tank may perform and is not intended to be mathematically equivalent 

to the primary standard, but it is rather intended to provide reasonable assurance that a tank 

certified at the higher temperature would pass the primary standard of 1.5 g/m2/day at 28°C. 

This adjusted standard at 40°C is based on data presented in the RIA and is intended to account 

for variability in how different materials will respond to increases in temperature. 

4-36
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.3.6 Tank permeation– under-cowl fuel tanks 

What Commenters Said: 

Yamaha commented it is unclear in the proposal if small, engine mounted fuel tanks 

would be subject to the proposed permeation standards. NMMA and Brunswick commented that 

there is no specific mention of these small tanks in §1060.103, as proposed. Yamaha stated that 

there is no credible evidence to show that small on engine mounted tanks are a contributor to HC 

emission losses during non-running/storage conditions. NMMA, Yamaha, and Brunswick 

argued that it is common industry practice for these small engine-mounted tanks to be drained of 

fuel prior to storage resulting in very low evaporative emissions. As an example of this, NMMA 

and Yamaha provided an excerpt from outboard engines owner’s manual which specified that the 

owner drain the gasoline from the tank when the engine is stored for prolonged periods of time 

(2 months or longer). 

Yamaha also commented that their portable engines with engine mounted tanks are dual 

fuel capable. What this means is Yamaha includes is a selector valve inline that provides for 2 

sources of fuel supply. The operator can select either a larger 3 or 6 gallon portable tank, or the 

much smaller available 1.2 liter on-engine tank. Based on their experience, Yamaha stated that 

most operators choose the external portable tank for its volume for extended operation and never 

use the engine mounted version. Due to their light weight, Yamaha claimed that these engines 

are normally removed for transportation and for storage both in boats and home garages. 

Brunswick and Yamaha recommended that EPA exclude engine-mounted tanks, 2.0 liters 

and under, from the fuel tank permeation standards. 

Letters: 

Commenter Document # 

Sea Ray 0683 

Suzuki 0698 

EMA 0691 

Yamaha 0721 

Mercury 0693 

Our Response: 

The proposed regulatory text clearly included engine-mounted fuel tanks under the 

proposed tank permeation standards. Proposed §1045.107 stated that “Other installed fuel tanks 

must meet permeation standards starting in the 2012 model year.” Proposed §1060.801 defined 

installed fuel tanks as “any fuel tank designed for delivering fuel to a Marine SI engine, 

excluding portable nonroad fuel tanks.” Due to the confusion expressed by commenters, we are 

adding a clarifying statement to §1060.103 that states that engine-mounted fuel tanks are an 

example of Marine SI fuel tanks. 

We do not believe that it is appropriate to rely on operator behavior as a control strategy 

for permeation emissions. Even in the cases where the operator drains the fuel tank prior to 

4-37 
Chapter 4: Evaporative Emissions 

storage, it is unlikely the tank will be drained completely. Any fuel or vapor left in the fuel tank 

would have the potential to permeate. In addition, the maintenance instructions provided by 

Yamaha and NMMA only suggest that the fuel tank be drained for prolonged storage. Other 

maintenance recommended for long storage included draining oil, fogging the engine, draining 

the cooling system, and greasing the spark-plug threads. These maintenance steps are clearly not 

intended to be performed after each engine use. Fuel would likely permeate through the fuel 

tank whenever the engine is not being put into long term storage. Although a 2.0 liter fuel tank 

is small compared to most marine fuel tanks, it is comparable in size to fuel tanks used on many 

Small SI applications, many of which are engine-mounted. As with Small SI fuel tanks, we 

believe that Marine SI fuel tanks, even engine-mounted tanks, contribute to HC emissions in our 

nation’s air. Therefore, we are finalizing the tank permeation standards for all Marine SI fuel 

tanks, including engine-mounted fuel tanks. 

4.3.7 Diurnal – installed fuel tanks 

What Commenters Said: 

The California Air Resources Board (ARB) commented that that the proposed lead time 

for the implementation of passively purged carbon canisters is also too lengthy. ARB argued 

that this technology is widely used and has been proven by the automotive industry and 

recommended that the diurnal standards be implemented with the 2009 model year. ARB also 

noted that actively purged canisters could further reduce vented emissions. ARB recommended 

that a diurnal performance standard be set for high production volume marine spark-ignition 

vessel manufacturers, arguing that, without a performance standard, U.S. EPA cannot validate 

emission reductions. ARB stated that a design-only standard would not take into account 

connector losses, carburetor emissions, and leaks from poorly designed integrated engines. As a 

result, they recommended that the diurnal standard include emissions from complete evaporative 

emission systems, to be measured over three days (without a carbon canister) or seven days (with 

a carbon canister), and be based on tank volume. This is consistent with on-road vehicle test 

procedures. 

Environmental Defense expressed support of EPA’s proposed diurnal standard and for a 

near term implementation date for marine fuel tanks. Environmental Defense noted that the 

proposed diurnal standard for marine engines will control diffusion emissions from recreational 

boats sufficiently. However, if EPA were not to finalize the diurnal standard, then 

Environmental Defense would object to the omission of a diffusion standard for marine engines. 

Because EPA did not propose running loss standards for marine engines, and diurnal emission 

control would help control running loss emissions, Environmental Defense commented that EPA 

should finalize a diurnal standard immediately. 

Delphi commented that many factors will affect the efficiency of the evaporative 

emissions system, including canister size, configuration (length vs. cross-section), carbon type, 

operating temperature, fuel vapor flow rate, and other factors which impact the HC adsorption 

capabilities of the canister. Delphi stated that proper installation and use of carbon canisters in 

marine applications (where diurnal emissions regulations are proposed) will effectively reduce 

evaporative emissions. Delphi expressed support for a useful life of five years. They commented 

4-38
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

that this useful life period is consistent with Delphi’s long-term experience with automotive 

canisters 

Delphi also stated that the proposed implementation date of 2010 is acceptable from a 

canister component perspective. Carbon canisters are a fairly mature technology. The canister 

designs currently intended for marine use are relatively simple designs. Delphi said that it will 

continue to work with NMMA and ABYC to define the canister design requirements and proper 

installation and use. Delphi did note that, input from NMMA and/or ABYC may indicate 

system-related challenges that may require additional time to solve. Delphi expressed support 

for the proposed requirement to design the system to prevent liquid fuel from entering the 

canister, noting that exposure to liquid fuel will significantly reduce the ability of the canister to 

adsorb HC vapors. Delphi stated that, following exposure to liquid fuel, purging the canister, 

particularly in a passive purge system as proposed for marine applications, would be a lengthy 

process, and permanent degradation in canister working capacity may result. Delphi also 

expressed support for the proposed alternative standard for non-trailerable boats because fuel 

temperature variation, and thus diurnal emissions will be less than that experienced on trailerable 

boats. 

NMMA said that they had performed successful in-use tests on carbon canisters installed 

on boats and had data showing sufficient emission reductions from passively purged canisters to 

meet the proposed standards. However, NMMA expressed concern that more time may be 

necessary to ensure that these systems are properly installed. One issue that manufacturers 

raised was that if the liquid fuel separator were to clog, or if the carbon canister were to be 

exposed to liquid fuel and clog, that this could result in pressurization of the fuel system. 

NMMA also stated that 3,000 boat builders would be potentially required to install carbon 

canisters and time would be necessary for the industry to develop installation standards that 

could be used by all boat builders to ensure that they are properly installing the carbon canisters 

in their boats. 

Several other fuel system component manufacturers and boat builders commented that 

the proposed diurnal emission standards are feasible, given enough lead time. However, they 

commented on a number of technical challenges that they would need to address. Boat builders 

commented that adequate space must be dedicated and that space will need to be located above 

the plane of the top surface of the fuel tank. In addition, the canister would need to be high 

enough to prevent liquid fuel from entering the canister during expected changes to the vessel's 

attitude during normal use. An alternative, presented in the comments, is the use of a 

liquid/vapor separator device. While effective, commenters expressed concern that the 

component would add complexity and cost-location for both items will have to allow access to 

the fittings for inspection to meet ABYC standards. Therefore, installation and access would 

need to be designed to be within the vessel's appearance. In addition, boat builders commented 

that a high number of different sized canisters would be burdensome. Several boat builders 

commented that further research and testing must be performed to ensure safe and effective 

installation of carbon canisters on boats. Inca recommended that the EPA provide a technical 

review of carbon-canister technology in 2010. 

4-39 
Chapter 4: Evaporative Emissions 

ABYC testified that the well-established technology of automotive carbon canisters is 

presenting many challenges when adapted to the marine environment. ABYC established a 

carbon canister working group in 2006 including Delphi, Meade-Westvaco, the US Coast Guard 

Office of Boating Safety and industry fuel component experts to discuss, and eventually 

overcome, the safety issues surrounding this solution. ABYC stated that they began writing a 

marine focused standard to address all aspects of a canister on board a boat due to the absence of 

a universally accepted standard on the construction and installation of a canister on a boat. As 

part of this effort, ABYC explained that size, construction, shock, vibration, installation, and 

service environments are all concerns that are being addressed. ABYC commented that the 

nature of the carbon and the canister itself causes some unique issues that could result in 

pressurization of a marine fuel tank which violates the 33 CFR regulations that apply to 

recreational boats fuel systems. ABYC referred to this issue as a challenge to overcome that will 

take time to effectively solve. 

The Coast Guard expressed concerns with the proposed option regarding the pressurizing 

of the fuel system, especially for large non-metallic fuel tanks (even to one psi), to meet the 

diurnal standards. Coast Guard stated that pressurizing non-metallic marine fuel tanks causes 

them to expand like a balloon which, among other problems caused by the expansion, may easily 

lead to fuel leaks in the tanks. Coast Guard also expressed concerns that the use of carbon 

canisters in fuel vent lines is not yet a proven marine technology. While they have been assured 

that the canisters can pass the battery of tests required of fuel system components, they have not 

yet seen test results. Coast Guard stated that they are continuing to work with a canister 

manufacturer in conducting appropriate testing but have not yet seen whether satisfactory results 

are achievable. Coast Guard commented that their main concern with the carbon canister option 

is the necessity for installing a check valve in the vent line to prevent liquid fuel from entering 

the canister. Coast Guard explained that the installation of this check valve may require the 

reconfiguration of the fuel systems in many boat models to prevent blockage of the vent line by 

liquid fuel when the boat is at an other than static float plane attitude which may in-turn require 

changes to the current industry fuel system standards. Additionally, there are no carbon canister 

construction or installation standards which Coast Guard believes may be critical safety 

considerations. Coast Guard stated that they remain optimistic that all of their concerns can 

eventually be satisfactorily addressed but we are commented that they believed more time may 

be needed for implementation of the diurnal standards. 

During the comment period, NMMA recommended model year 2011 as the appropriate 

implementation date for diurnal emission standards and commented that this would provide 

industry with sufficient time for sorting through the remaining technical issues associated with 

carbon canisters on boats. Several boat builders and other NMMA members requested additional 

lead time, many of which also recommended a 2011 implementation date. Brunswick 

commented in favor of a 2011 implementation date, but also recommended a phase-in approach 

so that ABYC could work on a standard for the canister, and address the possible pressurization 

issue. 

After the comment period closed, Brunswick provided more detailed information on a 

phase-in approach. Specifically, Brunswick recommended a phase-in of 40/80/100 percent of 

4-40
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

their boats in the 2011 through 2013 model years.3 When this approach was presented to EPA, it 

was also supported by NMMA and Genmar, who were in attendance. Brunswick commented 

that this phase-in was necessary for three reasons. First, they (and other large boat builders) have 

a large number of boat models that are independently designed and produced under individual 

brands. Brunswick commented that these brands, in many ways, each operate similar to a 

smaller business. Second, some of the boat designs have very limited space for the installation 

of canisters and would need substantial design changes, and therefore require more time. Third, 

Brunswick commented that a phase-in of the standards would allow them to better balance the 

demand for engineering resources. 

We also received comments regarding additional lead time for small businesses. This 

issue is discussed in Section 4.9, below. 

Letters: 

Commenter Document # 

NMMA 0688 

Environmental Defense 0648 

Yamaha 0721 

Suzuki 0698 

California ARB 0682 

U.S. Coast Guard 0631 

Delphi 0638 

Trident Rubber 0636 

Inca Molded Products 0700 

NMMA (hearing) 0642 

ABYC (hearing) 0642 

Sea Ray 0683 

S2Yachts 0697 

Grady-White Boats 0677 

North American Sleekcraft 0666 

Triton 0656 

Lund Boat Co 0655 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products 0652 

Lowe Boats 0660 

Godfrey 0645 

American Marine Sports 0639 

Cigarette Racing 0637 

Regal Marine Industry 0635 

Massachusetts Marine Trade Association 0634 

Regulator Marine Inc. 0632 

Ranger Boats 0628 

 Brunswick Boat Group, “Brunswick Boat Group Diurnal Emission Controls,” Presentation to U.S. EPA, April 4, 

2008. 

4-41 

3
Chapter 4: Evaporative Emissions 

Larson/Glastron Boats 0626 

Four Winns Boats 0650 

Premier Marine Inc, 0613 

Skeeter 0706 

Yellowfin 0681 

NMMA 0739 

Grady-White 0750 

Four Winns 0625 

Our Response: 

We are finalizing the diurnal emission standards, as proposed, for installed fuel tanks. In 

addition, we are finalizing provisions to allow for design-based certification to the diurnal 

emission standard. Due to the large variation in boat designs, we believe that design-based 

certification is valuable tool for reducing testing burden. To certify their products using designbased certification, manufacturers will describe, from an engineering perspective, how their fuel 

systems meet the applicable design specifications. We believe there are several designs that use 

established technologies that are well understood to have certain emission characteristics. At the 

same time, while design-based certification is a useful tool for reducing the test burden 

associated with certification, this does not remove a manufacturer’s liability for meeting all 

applicable requirements throughout the useful life of the engine, equipment or vessel. 

The primary evaporative emission control device used in automotive applications is a 

carbon canister. With this technology, vapor generated in the tank is vented to a canister 

containing activated carbon. The fuel tank must be sealed such that the only venting that occurs 

is through the carbon canister. This prevents more than a minimal amount of positive or 

negative pressure in the tank. The activated carbon collects and stores the hydrocarbons. The 

activated carbon bed in the canister is refreshed by purging. This same basic technology may be 

used in marine applications as well. However, in a marine application, an engine purge is less 

practical than in automotive applications because of the potential complications with the engine 

and tank created by the variety of manufacturers and engine/tank configurations in the fleet each 

year. In addition, boat engines are not operated as regularly as automotive engines, causing 

extended periods between active purges. Even without an active purge, carbon canisters may be 

used to significantly reduce diurnal emissions because the canister is purged sufficiently during 

cooling periods (“passive purge”). When the fuel in the tank cools, fresh air is drawn back 

through the canister into the fuel tank. This fresh air partially purges the canister and returns 

hydrocarbons to the fuel tank. This creates open sites in the carbon so the canister can again 

collect vapor during the next heating event. A passively purged canister is capable of reducing 

diurnal emissions by more than 60 percent due to the normal airflow across the canister bed 

during cooling periods. 

If a manufacturer uses a canister-based system to comply with the standard applicable to 

the specific tank, we are also requiring that manufacturers design their systems not to allow 

liquid gasoline to reach the canister during refueling or from fuel sloshing or volume expansion. 

Liquid gasoline will significantly degrade the carbon’s ability to capture hydrocarbon vapors. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Currently, industry consensus standards in ABYC H-244 address, to some extent, spillage during 

refueling and due to fuel expansion. However, under these guidelines, the refueling “blow back” 

test is only for a partial fill and does not necessarily prevent fuel from spilling out the vent line 

(where a canister would likely be installed) during refueling. In addition, although ABYC 

recommends that a fuel system be designed to contain 5 percent fuel expansion, the actual 

requirement can be met by the manufacturer by simply lowering the fuel tank capacity rating 

without designing the fuel system to prevent overfilling. We do not believe that a system that 

simply meets the current ABYC requirements would necessarily be adequate to demonstrate that 

liquid fuel would not reach the carbon canister. However, ABYC commented that it intends to 

revisit its standards to include proper canister installation instructions and an improved fuel 

spillage performance test. One example of an approach to protect the canister from exposure to 

liquid gasoline is a design in which the canister is mounted higher than the fuel level and a small 

orifice or a float valve is installed in the vent line to stop the flow of liquid gasoline to the 

canister. 

There was a range of several years in the commenter’s opinions on the proper 

implementation date for marine diurnal emission standards. The recommended implementation 

date ranged from the 2009 model year to a three-year phase-in from 2011 through 2013. At this 

point, many manufacturers are producing their 2009 model boats already; therefore a 2009 model 

year implementation date is clearly too early. Personal watercraft currently use sealed fuel 

systems for preventing fuel from exiting, or water from entering, the fuel tank during typical 

operation. These vessels use pressure-relief valves for preventing excessive positive pressure in 

the fuel system; the pressure to trigger the valve may range from 0.5 to 4.0 psi. Such a fuel 

system also uses a low-pressure vacuum relief valve to allow the engine to draw fuel from the 

tank during operation. Because we do not expect significant engineering changes for these 

vessels, we are implementing the diurnal emission standards, for PWC, beginning with 2010 

model year. 

Vessels with installed fuel tanks are typically designed with open vent systems. In their 

comments, marine vessel manufacturers expressed general support of the feasibility of using 

carbon canisters on boats. In addition, the marine industry has expressed an interest in 

developing consensus standards for the installation of carbon canisters in boats. However, they 

commented that the development of these consensus standards will take time and that a phase-in 

would be needed for an orderly transition with regard to installing diurnal emission controls 

across their product lines. We recognize that canister technology has not yet been applied 

commercially to marine applications and additional lead time may be necessary to work out 

various technical parameters associated with the large variety of boat models and tanks. Many 

boat designs have ample space, within hull, to allow for canister installation without significant 

mold changes. However, we believe that that a one year phase-in approach will give boat 

builders the flexibility they need to balance their engineering resources and to address any boat 

designs with limited space for the installation of canisters. Therefore, for fuel tanks installed on 

vessels, we are finalizing a phase-in beginning on July 31, 2011. In the period from July 31, 

2011 through July 31, 2012, 50 percent of the boats produced by each company must meet the 

4

 American Boat and Yacht Council, “Standards and Technical Information Reports for Small Craft; H-24 Gasoline 

Fuel Systems,” July, 2007. 

4-43 
Chapter 4: Evaporative Emissions 

diurnal standard described above. Beginning on August 1, 2012, all marine fuel tanks and boats 

must meet the diurnal emission standard. 

We did not propose running loss or diffusion standards for marine vessels. Installed 

marine fuel tanks are generally not mounted near the engine or other heat sources so running 

losses should be very low. A possible exception to this is for personal watercraft or other small 

boats where the fuel tank may be closer to the engine. However, under the new standard for 

controlling diurnal emissions, we expect that PWC manufacturers will design their fuel tanks to 

stay pressurized up to 1 psi. This will also help control running loss emissions. The use of a 

carbon canister will also help control diurnal emissions for other installations where the fuel tank 

may be near the engine. The same passive purge phenomenon that limits venting emissions 

caused by diurnal tank heating would limit venting emissions from fuel tanks heated by engine 

operation. Any increase in fuel temperature resulting from engine operation will cause a 

potential for fuel tank vapor emissions that are generated in a manner similar to fuel tank diurnal 

emissions. We are therefore not allowing manufacturers to disable their approaches for 

controlling diurnal emissions during engine operation. This will ensure that any running loss 

emissions that will otherwise occur will be controlled to a comparable degree as diurnal 

emissions. In addition, we believe the diurnal emission standard will lead manufacturers to 

adopt technologies that automatically limit diffusion losses, so there is no need to set a separate 

diffusion standard for those systems. 

4.3.8 Diurnal – portable fuel tanks 

What Commenters Said: 

Suzuki expressed support of the proposed concept of a diurnal requirement for portable 

fuel tanks that requires they be equipped with self-sealing gas caps up to a internal pressure of 

5.0 psi, and that the tanks must be self sealing when they are disconnected from the outboard 

engine. Suzuki commented that the requirement is technically feasible given sufficient leadtime. They argued that compliance with this all-new requirement will require the development 

of new components, which must also be validated to ensure proper function and durability in all 

market conditions. Suzuki and NMMA requested that EPA adopt an implementation date of the 

2011 model year for the portable fuel tank diurnal requirement to allow for the lead time needed 

to develop the new components. 

Letters: 

Commenter Document # 

NMMA 0688 

Suzuki 0698 

Our Response: 

The design standard for portable marine fuel tanks can be met with relatively straightforward technology. These fuel tanks are already designed to withstand the pressure of being 

stored in a sealed condition, which may lead to pressures substantially larger than 5.0 psi. The 

manual valve simply needs to be replaced with an automatic pressure/vacuum-relief valve such 

4-44 
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

as have been used in other fuel system applications for decades. In addition, the hose 

connections are typically designed to seal when the tank is disconnected from the engine, even in 

today’s designs. However, we recognize that some additional lead time may be necessary for the 

development and validation of new components. Therefore we are providing an additional year 

of lead time beyond the proposed implementation date. Specifically, we are implementing the 

new diurnal standards for portable marine fuel tanks in 2010. We believe these requirements 

will not result in a significant change from current practice so this date will provide sufficient 

lead time for manufacturers to comply with standards. 

4.3.9 Diurnal – engine-mounted fuel tanks 

What Commenters Said: 

NMMA expressed support of the proposed diurnal requirements for engine-mounted fuel 

tanks. NMMA stated that, in the case of engine-mounted fuel tanks, compliance with the 

proposed diurnal standard is feasible through the use of pressure-sealing gas caps. However, 

NMMA noted that components that can meet these specifications must still be developed. Given 

the state of the technology, NMMA recommended that any diurnal requirements for very small 

engine-mounted tanks be delayed until model year 2011. Yamaha also expressed support EPA 

proposal to control diurnal emission loss from engine mounted fuel tanks in 2011. 

Letters: 

Commenter Document # 

NMMA 0688 

Yamaha 0721 

Our Response: 

We agree that the diurnal requirements can be met for engine-mounted fuel tanks, 

through the use of sealed systems with pressure relief valves. However, we recognize that some 

additional lead time may be necessary for the development and validation of new components. 

Unlike portable fuel tanks, these tanks are not currently designed to be sealed for storage. 

Therefore we are providing two additional years of lead time beyond the proposed 

implementation date. Specifically, we are implementing the new diurnal standards for engine 

mounted fuel beginning on July 31, 2011. 

4.4 Averaging, banking, and trading 

What Commenters Said: 

EMA and OPEI commented that ABT programs provide important flexibility and 

incentive to regulated parties, and are a major contributing factor to the creation of a balanced 

and effective regulatory program. ABT programs generate a substantial amount of emissions 

reduction over and above reductions effected by regulation, at a low cost to regulated parties. 

EMA and OPEI supported the need for a nonhandheld fuel tank ABT program. They both 

commented that it is imperative that the evaporative AB&T program included in the final rule is 

4-45 
Chapter 4: Evaporative Emissions 

designed to generate the greatest environmental benefit possible. In order to take full advantage 

of this mutually beneficial opportunity to achieve greater emissions reductions, EPA must ensure 

that the AB&T program incorporated into the final rule is both effective and viable. 

OPEI supported the proposed ABT program for handheld fuel tanks and fuel lines. OPEI 

also supported the continuation of the handheld fuel tank ABT program after the implementation 

of the FEL caps. OPEI did not support the use of an ABT program for service tanks. They noted 

that no controls exist for the manufacture and sale of replacement tanks and the market could be 

flooded with unneeded and unnecessary parts for the sake of credit generation. 

EMA commented that fuel lines should not be included in the fuel tank permeation 

AB&T program. As a result, the temperature difference between the fuel line permeation test 

and the fuel tank permeation test should not be a concern. In addition, the 23oC test temperature 

for fuel line is a well established industry standard that provides consistency throughout the fuel 

line industry regardless of final product application/regulation. 

EMA commented on §1054.706 “How do I generate and calculate evaporative emission 

credits?” They believe the ability to generate credits should be extended to engine manufacturers 

for engines sold with integrated fuel systems that include fuel tanks. 

EMA commented on §1060.130(b)(5) “What installation instructions must I give to 

equipment manufacturers?” The evaporative ABT program should be limited to OEM and 

engine manufacturers. Allowing component manufacturers to participate in ABT creates 

incredible complexity. 

EMA noted that the proposed ABT program does not allow the use of presumptively 

compliant materials, such as steel or multi-layer plastics (that will generate significant 

environmental benefit), to generate credits. EMA presumed the constraint on the credit 

generating benefits of these very low emitting materials is based on a concern that existing tanks 

would generate emission credits even though those benefits already are included in the baseline 

emission inventory analysis. EMA recommended that EPA allow these very low emitting 

products to generate emission credits if they are used to replace existing high permeation 

materials. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

EPA is retaining an evaporative emission ABT program for nonhandheld fuel tanks in the 

final regulations. EPA believes such a program will provide flexibility for equipment 

manufacturers to comply with the new fuel tank permeation requirements for nonhandheld 

equipment. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

EPA is making some changes to the proposed evaporative emission ABT program for 

handheld equipment. These changes are in response to changes made in the final regulations 

regarding cold weather fuel lines and structurally integrated fuel tanks for handheld equipment. 

(See sections 4.2.3 and 4.2.5 for information on those changes.) First, the evaporative emission 

ABT program for handheld equipment will no longer allow credits to be exchanged between fuel 

tanks and fuel hose. Instead, there will be one ABT program for fuel tanks used in handheld 

equipment and a second temporary ABT program for fuel lines used in cold-weather equipment. 

Without changes to the proposed handheld fuel tank and fuel hose ABT program, EPA is 

concerned that manufacturers would likely have been able to keep their existing cold-weather 

fuel lines without making any improvements to those designs. This was not the intent of the 

proposed program. In response, EPA is adopting a temporary fuel line averaging program for 

cold-weather equipment. Manufacturers would not be allowed to bank or trade credits under the 

cold-weather fuel line program. As described in Section 4.2.3, EPA believes that cold-weather 

fuel lines present unique challenges and limitations with regard to permeation control. Given the 

declining set of standards EPA is adopting for cold-weather fuel lines, the temporary coldweather fuel line averaging program will provide manufacturers with the ability to redesign their 

cold-weather fuel lines to meet lower permeation levels in an efficient and timely manner. The 

cold-weather averaging program will no longer be available in the 2016 model year when all 

cold-weather fuel lines will need to demonstrate compliance with a 225 g/m2

/day standard. With 

regard to other types of handheld equipment, EPA believes that manufacturers should be able to 

meet the fuel line permeation standard of 15 g/m2/day without the need for credits and is 

therefore not including those fuel lines in the temporary fuel line averaging program. 

The second change to the ABT program for handheld equipment is in regard to the 

provisions for structurally integrated fuel tanks. As described in Section 4.2.5, EPA is finalizing 

a 1.5 g/m2/day standard for all handheld fuel tanks, instead of the slightly higher proposed level 

of 2.5 g/m2/day for structurally integrated fuel tanks. Therefore, handheld equipment 

manufacturers will generate and use credits for any fuel tank based on the standard of 1.5 

g/m2/day, including structurally integrated fuel tanks. As proposed, the evaporative emission 

ABT program for handheld equipment will allow manufacturers to use credits across all three 

classes of handheld engines/equipment. 

In response to the comments on allowing engines manufacturers to participate in the 

evaporative ABT program, EPA agrees that engine manufacturers should be able to participate in 

the ABT program if they assemble the entire fuel system along with the engine. EPA believes it 

makes sense because the engine manufacturer is expected to be the entity certifying their 

engine/fuel system to the evaporative standards in these situations and not the equipment 

manufacturer (such as with handheld engines or personal watercraft). EPA expects this will 

generally be the case with the large majority of Class I nonhandheld engines as well as nearly all 

handheld engines. Therefore, the regulations have been revised to allow engine manufacturers 

that provide the complete fuel system with the engine to participate in the ABT program. It 

should be noted that if an engine manufacturer participates in the evaporative ABT program for a 

given engine/fuel system, then the equipment manufacturer who purchases those engines/fuel 

systems cannot generate its own credits for those products (or would not have to use its own 

credits for those products either). That would be double-counting of credits. 

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Chapter 4: Evaporative Emissions 

With regard to the comments on including component manufacturers (i.e., tank 

manufacturers) in the ABT program, EPA is retaining the provisions as proposed. Tank 

manufacturers that certify their fuel tanks with EPA can participate in the ABT program. 

However, their participation is limited to selecting the appropriate FEL for their tank design. 

The tank manufacturer cannot generate credits in the ABT program. Only equipment 

manufacturers (or engine manufacturers that provide a complete fuel system with the engine) 

may earn/use credits and demonstrate compliance under the evaporative ABT program. EPA 

believes it is appropriate to allow tank manufacturers to participate in the ABT program in this 

manner to facilitate the use of the ABT program by equipment manufacturers who generally rely 

on outside sources for their fuel tanks and are required to demonstrate compliance with the 

overall evaporative requirements for their equipment. 

In regard to the comment on service/replacement tanks, EPA agrees it is not appropriate 

to include such tanks in the ABT program. Equipment manufacturers will be required to 

demonstrate that their equipment models meet the evaporative emission standards. If the 

certified equipment uses a fuel tank included in the ABT program, the credits generated were 

based on a useful life of five years. Therefore, if the tank being replaced is less than five years 

old, the replacement tank would result in double counting of some of the credits. While 

manufacturers could potentially gather information to account for the age of the fuel tank being 

replaced, EPA does not want to complicate the provisions of the ABT program and is therefore 

not allowing replacement tanks to be included in the ABT program. 

With regard to the comments on steel tanks, EPA is retaining the provisions for metal 

tanks as proposed. Metal tanks will not be included in the ABT program. While EPA 

acknowledges that these tanks would have permeation rates well below the standard, there is 

extensive use of metal tanks today. We believe it would be difficult to allow these emission 

credits without undercutting the stringency of the standard and the expected emission reductions 

from the standard. Therefore, we are not allowing metal tanks to be included in the ABT 

program. 

With regard to multi-layer tanks, EPA did propose to allow such tanks to participate in 

the evaporative emission ABT program under a specified condition. To participate in the ABT 

program, a manufacturer must establish an FEL for the multi-layer fuel tank based on an actual 

measurement of permeation emissions. EPA is retaining that provision for the final rule. 

However, it should be noted that manufacturers that certify their multi-layer tanks by design 

cannot include those tanks in the ABT program. 

4.4.1 Averaging sets 

What Commenters Said: 

EMA and OPEI commented that cross-class trading restrictions are generally not 

beneficial. Because the tank permeation standards are in terms of grams per square meter, EMA 

and OPEI believe the relative tank size between Class I and Class II should not impact 

competitive market or technology development. 

4-48
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

EMA commented that cross category trading between Small SI and marine could create a 

significant competitive market issue and should not be allowed. 

OPEI commented that trading between handheld and non-handheld should be restricted 

except as proposed in §1054 subpart H. 

Honda commented that EPA should clarify in the final rule when and if an engine less 

than 80cc would be categorized as nonhandheld for ABT purposes if EPA does not allow Phase 

3 cross class averaging. Clarification or added guidance in the final rule would be useful where 

an engine less than 80cc is used in a nonhandheld product would qualify as nonhandheld for 

purposes of ABT, such as an engine used in a ground-supported mini-tiller. (Also included in 

Section 2.3.2) 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Honda 0705 

Our Response: 

EPA is retaining the averaging sets for the evaporative emission ABT programs as 

proposed, with one change for nonhandheld equipment. As proposed, EPA will not allow 

averaging of emissions between Marine SI vessels and Small SI equipment. In the Marine SI 

evaporative emission ABT program, EPA will allow averaging of emissions between OB/PWC 

vessels and SD/I vessels. (Portable marine fuel tanks are not included in the Marine SI 

evaporative emission ABT program.) In the Small SI evaporative emission ABT program, EPA 

will not allow averaging of emissions between handheld equipment and nonhandheld equipment. 

For the nonhandheld evaporative emission ABT program, EPA is dropping the restriction 

on averaging between Class I and Class II equipment. In the proposal, EPA noted concerns that 

trading across the categories could give an unfair competitive advantage to manufacturers with 

broad product lines. However, given that the trade organization representing equipment 

manufacturers does not believe the restriction is necessary due to competitiveness concerns, EPA 

is less concerned about the need for the restriction. Furthermore, because EPA is adopting FEL 

caps for the fuel tanks, manufacturers eventually will be required to design all of their tanks to 

comply with the permeation standards. This also lessens our concerns about manufacturers using 

the ABT program to their advantage in the marketplace since all fuel tanks will need to employ 

some level of permeation control. Therefore, we are dropping the restriction on trading of 

evaporative emission credits across Class I and Class II equipment. (It should be noted that the 

proposed restriction between Class I and Class II equipment in the early allowance programs will 

still apply. EPA believes this restriction is still appropriate because there is no adjustment in the 

early allowance program for the size of the fuel tank, unlike the ABT program in which credits 

are calculated based on the surface area of the tank.) 

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Chapter 4: Evaporative Emissions 

In regard to the comments on whether engines certified to the handheld standards can 

generate nonhandheld credits, EPA proposed to allow manufacturers to generate nonhandheld 

ABT credits from equipment powered by engines at or below 80cc (which are subject to the 

handheld standards) if a manufacturer has determined the application is a nonhandheld 

application. A nonhandheld application is an application that does not meet the handheld 

definition as defined in §1054.801 of the regulations. EPA is retaining that provision in the final 

rule. Therefore, a manufacturer can generate nonhandheld emission credits from equipment 

powered by engines at or below 80cc that are subject to the handheld evaporative standards if the 

manufacturer determines the equipment is actually a nonhandheld application. These 

nonhandheld credits could be used within Class I and Class II to demonstrate compliance with 

the evaporative emission standards. 

4.4.2 Early Credits 

What Commenters Said: 

NMMA noted that EPA proposed an early credit system for companies subject to the 

evaporative emissions standards in Part 1060. Under the program, manufacturers certifying early 

to the fuel tank permeation standards would be able to earn allowances that they could use to 

offset high-emitting fuel tanks at a later date. No cross trading between portable fuel tanks, 

PWC, and other installed fuel tanks would be permitted. For PWC and portable fuel tanks, 

allowances could be earned for compliant tanks installed prior to 2011 and could be used through 

the 2013 model year. For other installed tanks, allowances could be earned for compliant tanks 

installed prior to 2012 and could be used through the 2014 model year. NMMA commented that 

it appreciates EPA’s efforts to provide flexibility and reward early compliance with the proposed 

standards. However, NMMA noted that an early credit program should not serve as a substitute 

for additional time for compliance with the new standards. (As noted in Section 4.3.5, NMMA 

submitted comments noting that its members have serious reservations about imposing a 2012 

compliance deadline for rotational-molded tanks. To address these concerns, NMMA 

recommended that EPA perform a technical review in 2010 and impose an implementation date 

based on the findings.) 

Letters: 

Commenter Document # 

NMMA 0688 

Our Response: 

EPA is retaining the early compliance program for Marine SI fuel tanks as proposed. 

EPA believes the early compliance program will encourage the early introduction of low 

permeation products and will provide vessel manufacturers with additional flexibility as they 

transition to the new standards. (With regard to the 2012 compliance deadline for rotationalmolded tanks, as noted in Section 4.3.5, EPA intends to hold periodic progress reviews with 

small businesses that manufacture rotation-mold fuel tanks. The purpose of these progress 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

reviews will be to monitor the progress of individual companies towards compliance with the 

tank permeation standards and to provide feedback as needed.) 

4.4.3 Credit Lifetime 

What Commenters Said: 

OPEI opposed the proposition that any engine-exhaust or evaporative credits generated 

by a manufacturer should have an arbitrary life period. Emission credits are either generated 

through the voluntary early implementation of new emission control technology or introduction 

of products that are cleaner than required by the applicable emission standard. They noted that 

such credits are generated at a cost to the manufacturer, and are granted in exchange for the 

manufacturer’s independent decision to produce products that provide additional benefits to the 

environment. These credits are important assets that should not be arbitrarily lost due to time or 

actions not under the manufacturer’s control. 

EMA also commented that banked emission credits should not have a limited life. The 

credits were generated based on a product that was sold and provided environmental benefit 

relative to the requirement. Whether or not that piece of equipment is still in use is immaterial, 

since the benefit was already provided. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

EPA does not believe a limit on the life of the credits is needed at this time for the 

evaporative emission ABT programs adopted with this rule. While EPA is adopting an indefinite 

credit life for the ABT program, manufacturers should not assume that this means those credits 

will be available without any restrictions on their use if, or when, EPA should consider a new 

round of evaporative emission standards in the future. As part of any future rulemaking, EPA 

would expect to consider ways to ensure that the evaporative emission ABT credits existing at 

that time would not result in a delay of any future standards that would prevent us from requiring 

the greatest degree of achievable emission reductions. 

4.4.4 FEL caps 

What Commenters Said: 

In response to EPA’s proposal to set an FEL cap for fuel tanks after the program has been 

in effect for three years, OPEI and EMA commented that because there was not previously a 

control standard from which to determine an FEL cap, it is not appropriate to now assign an 

arbitrary FEL cap. Implementation of an FEL cap at any time during Phase 3 precludes the 

option for manufacturers to continue to utilize existing technologies for low volume products 

4-51 
Chapter 4: Evaporative Emissions 

that do not justify the design, development, or capital expense associated with the 

implementation of prescribed emission controls. If a manufacturer can either generate or trade 

for sufficient credits to continue the use of relatively high emission level pre-compliance 

products the ABT program should not preclude them from doing so. 

In response to EPA’s request for comment on the usefulness of an ABT program after we 

implement an FEL cap, OPEI and EMA supported the continued need for an ABT program and 

commented that an FEL cap without an ABT program would not allow the flexibility required by 

manufacturers. They noted that it is not clear how a product could be certified to any level other 

than the prescribed standard without an ABT program irrespective of the use of an FEL cap. 

EMA and OPEI commented that the proposed alternative FEL cap associated with testing 

at 40°C is not equivalent to the FEL cap at 28°C. The averaged results for Fuel C and Fuel CE10 

predict that the permeation rate will increase by a factor of 2 between 28°C and 40°C. If an FEL 

cap is required, they commented that the alternative caps prescribed at 40°C should be changed 

to be 2 times the cap at 28°C in order to provide equivalent stringency. Therefore, the alternative 

FEL cap at 40°C should be changed to 10.0 g/m2

/day to be equivalent stringency as the 28°C cap 

(and 6.0 g/m2

/day for structurally integrated nylon tanks and 16.0 g/m2/day for small-volume 

manufacturers). 

OPEI noted that they agree with the proposed FEL caps for handheld engines/equipment. 

In addition, OPEI requested that EPA consider an FEL cap of 5.0 g/m2/day for structurally 

integrated tanks since the higher cap would not result in any increase in emissions when using 

the ABT program. 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

With regard to the comments on whether EPA should have an FEL cap for fuel tanks 

when there is no previous standard, EPA is retaining the FEL caps as proposed (with one change 

for structurally integrated fuel tanks as described below). EPA believes that equipment and 

vessel manufacturers eventually should be required to apply low-permeation technology to all of 

their fuel tank designs. In the short term, we would not have FEL caps for the fuel tanks. 

However, starting in 2015 for handheld equipment and Class I equipment, 2014 for Class II 

equipment, 2014 for PWC, and 2015 for installed marine fuel tanks, the FEL cap would apply. 

Therefore, manufacturers could continue using current uncontrolled fuel tank designs for the first 

few years, provided they have sufficient credits to offset the higher permeation levels from those 

fuel tanks. However, starting with the dates noted above, manufacturers would need to employ 

low-permeation technologies on all of their equipment. Given the FEL cap of 5.0 g/m2

/day (or 

8.0 g/m2

/day Small SI small volume families), manufacturers would still need to improve their 

existing tank designs, but they may be able to employ simpler, less expensive technologies that 

meet the FEL cap (but not the 1.5 g m2

/day standard) such as thicker walled fuel tanks. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

With regard to the comments on the level of the FEL caps for the alternative permeation 

standard at 40oC, EPA is retaining the FEL caps for the higher temperature testing as proposed. 

The higher temperature permeation standards have been included in this rule as an alternative 

standard because manufacturers that wish to certify with California ARB are required to perform 

fuel tank testing at 40oC and EPA wanted to provide a means for manufacturers to use that 

information for certifying with EPA. Based on permeation results from fuel tanks tested at 28oC 

and 40oC, EPA has seen a range in the effect of temperature on permeation emissions depending 

on the fuel tank material. Therefore, in selecting the FEL caps for the higher temperature 

alternative standard, EPA has selected a limit that provides a high level of confidence that the 

fuel tank would also comply with the FEL cap associated with the testing at the normal testing 

conditions of 28oC. For the available data representing a range of materials and control 

technologies, the selected FEL caps for high-temperature testing represent the value that 

corresponds to a relatively worst-case condition for taking compliant products tested at 40°C and 

showing that they would also comply when tested at 28°C. 

With regard to the FEL cap for structurally integrated tanks, EPA is revising the FEL cap 

for structurally integrated fuel tanks. As described in Section 4.2.5, EPA is finalizing the same 

permeation standard for structurally integrated fuel tanks as for all other tanks. Therefore, EPA 

believes it is appropriate to apply the same FEL cap of 5.0 g/m2

/day to structurally integrated 

fuel tanks (or 8.0 g/m2

/day Small SI small volume families) that would apply to all other fuel 

tanks. 

4.4.5 Other ABT Issues 

What Commenters Said: 

OPEI supported the credit adjustment for the effect of different test temperatures on fuel 

tank permeation measurements. 

OPEI commented that paragraph 1054.706(b) is confusing and EPA’s intent is not 

understood. For example if an FEL of 4.5 g/m2

/day is used for a tank, paragraph (b)(1) says it is 

not allowed, yet such an emission level is allowed under paragraph 1054.110(b). OPEI 

suggested that paragraph (b)(1) be deleted. In addition, paragraph (b)(2) should be revised to 

reflect that if a manufacturer chooses not to test they could use a default level of 10.4 g/m2

/day. 

OPEI commented that the calculation of emission credits for structurally integrated tanks 

in paragraph 1054.706(c) is based on levels established for testing at 28oC. The last two lines 

need to be revised to reflect the calculation of positive credits for a standard of 2.5 g/m2

/day at 

40oC and the calculation of negative credits at a level of 4.0 g/m2/day when tested at 40oC. 

EMA commented on §1054.706(a) “How do I generate and calculate evaporative 

emission credits?” They believe the final regulations need more detail regarding how the “Total 

Area” is calculated. EMA recommended that “Total Area” should be calculated by multiplying 

the projected domestic sales volume with internal surface area of each fuel tank design within a 

family. 

4-53 
Chapter 4: Evaporative Emissions 

EMA commented on §1054.706(b)(1) “How do I generate and calculate evaporative 

emission credits?” They believe the requirement to measure emissions from every tank without 

an FEL is not appropriate. A manufacturer should have the option to measure permeation from 

the worst case tank, as determined using good engineering judgment. 

EMA commented on §1054.715(b) “How do I bank emission credits?” They believe 

reserve credits cannot be traded. Therefore, EMA recommended that the reference to “trading” 

should be deleted from this section. (Also included in 2.3.5) 

EMA commented on §1054.725(b)(2) “What must I include in my application for 

certification?” They believe engine families that generate or use credits at the time of 

certification should not be required to designate their credit destination or origin within the 

averaging set. (Also included in 2.3.5) 

EMA commented on §1054.730(f)(3) “What ABT reports must I send to EPA?” They 

believe that if an error mistakenly increases a manufacturer’s balance of emission credits, 

correction of the errors and recalculation of the balance of emission credits should be undertaken 

at the manufacturer’s discretion. Manufacturers should not be required to correct the errors and 

recalculate the balance of emission credits as currently proposed. (Also included in 2.3.5) 

EMA commented on §1054.735(d) “What records must I keep?” They believe the 

requirement to keep additional records for each engine or piece of equipment including the 

engine identification number, build date and assembly plant is excessive and beyond the current 

requirements of 40 CFR Part 90.209. These additional record keeping requirements either 

should be deleted or replaced with engine manufacturer records associated with products 

produced. (Also included in 2.3.5) 

EMA commented on §1054.735(e) “What records must I keep?” They believe that this 

section, as drafted, appears to be arbitrary and capricious. EPA should not be allowed to require 

manufacturers to keep additional unspecified records or demand additional information not 

required by the rule without a proper purpose or for cause. EPA should be required to support 

any imposition of additional record keeping requirements or demand for additional information 

with specific and appropriate reasons. Further, such decisions should not be made unilaterally by 

EPA, and the manufacturer must have the ability to question any such request and, if necessary, 

request a formal hearing process. (Also included in 2.3.5) 

Letters: 

Commenter Document # 

OPEI 0675 

EMA 0691 

Our Response: 

Regarding the comment on the adjustment to credit calculations for the effects of 

temperature, EPA is adopting the adjustment as proposed. Manufacturers earning credits based 

on the alternative standard at a higher temperature of 40oC will apply a factor of 0.6 to determine 

the number of credits they generate or use. 

EPA agrees that additional language should be added to the regulations to clarify that 

credits are based on the total internal surface area for all fuel tanks in the emission family. This 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

would be calculated by multiplying the production volume of each fuel tank design by its 

internal surface area and adding each of the resulting values together. 

EPA has revised the language regarding the fuel tank FEL language in §1054.706(b) to 

clarify the original intent of the proposal. The revised language provides two options to 

manufacturers for the tanks included in the ABT program. Manufacturers can establish FELs for 

each of their fuel tank families based on permeation testing of each tank design. Alternatively, 

manufacturers may establish FELs for all of their “controlled” fuel tanks (i.e., those tanks for 

which the manufacturer has applied some type of low-permeation technology or material and 

presumed to have an FEL of less than 5.0 g/m2/day) and assume an FEL of 10.4 g/m2/day for all 

remaining “uncontrolled” fuel tanks. Manufacturers are not allowed to pick and choose which 

uncontrolled fuel tanks they want to test. They either must test all of the uncontrolled tank 

designs (and establish an FEL for each tank design based on the results) or they must assume an 

FEL of 10.4 g/ m2

/day for each uncontrolled tank design. If a manufacturer wants to test their 

uncontrolled fuel tanks, EPA believes the manufacturers must test all of them and not just a 

“worst-case” tank design, since it may difficult to justify which design is truly the “worst-case” 

among the uncontrolled tanks. 

EPA has deleted the paragraph regarding the comments on the calculation of credits for 

structurally integrated fuel tanks in §1054.706(c). As noted in Section 4.2.5, EPA has deleted 

the separate standards for structurally integrated fuel tanks from the final regulations. Therefore, 

the information in paragraph (c) of §1054.706 is no longer needed. 

For the remaining comments on §1054.715(b), §1054.725(b)(2), §1054.730(f)(3), 

§1054.735(d), and §1054.735(e), EPA responded to these comments in Section 2.3.5 of this 

document since the comments also applied to the exhaust ABT program for Small SI engines. 

The reader is directed to that discussion for a response to these comments. 

4.5 Other requirements 

4.5.1 Refueling– Marine SI 

What Commenters Said: 

Enviro-Fill described the extent of the problem related to refueling spillage from marine 

vessels. While there are no known studies that accurately quantify the problem, there are plenty 

of articles documenting how extensive the fuel spill problem is. Enviro-Fill referenced letters 

from fuel dock operators and boat owners supporting changes that would reduce the occurrence 

of refueling spillage. One operator stated that the majority of the boats refueled at his marina 

spill through the vent. 

Enviro-Fill observed that there are regulations and standards in place for building boats. 

US Coast Guard regulations are mandatory while ABYC’s specifications are followed 

voluntarily. This system seems to work; however, there are some shortcomings in the standards. 

ABYC’s standard (H-24) allows a manufacturer to rate a fuel tank, for example, at 21 gallons 

even though the tank can hold 26 gallons. The extra capacity is considered to be for expansion. 

However, an operator will typically fill the tank to 26 gallons, leaving no room for expansion. 

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As this fuel warms and expands, five percent of the volume (1.3 gallons) could be expelled from 

the tank. ABYC or EPA need to adopt standards and procedures that properly test marine 

refueling systems to require designs that prevent spillage. A proper arrangement would be for 

automatic refueling shutoff to occur at fill rates between 5 and 20 gallons per minute such that no 

spitback or spillage occurs and five percent of tank volume is reserved for expansion. Such a 

solution would comply with section 311 of the Clean Water Act, which states that it is illegal to 

dump any petroleum product in the waters of this country. 

Enviro-Fill stated that they have developed a technology to prevent spitback, spillage, or 

overfill when refueling boats. The technology senses the fuel level in the tank and activates the 

nozzle shutoff automatically when the fuel level reaches a predetermined level. An independent 

laboratory tested the prototype system by filling a tank 25,000 times at 15 gallons per minute, 

allowing the system to shut off the nozzle each time without spilling any fuel and without filling 

the tank past the 95 percent fill level. This would require hardware changes to the fuel tank and 

filler neck (not the hull or deck) for an estimated total cost of $100, though that cost impact may 

be reduced to the extent that other components may no longer be needed. There would also be 

cost savings from no longer spilling fuel or cleaning up the spilled fuel. 

Enviro-Fill’s technology keeps fuel from entering carbon canisters without a check valve. 

This technology depends on a standardized fuel nozzle, so they recommend that EPA adopt the 

nozzle specifications described in the proposed rule on the same schedule as the other 

requirements in the rule. Enviro-Fill recommended a nominal spout diameter of 1.187 inches 

because that size is commonly found at marinas today. 

NMMA suggested that EPA’s proposed provision requiring vessel designs that allow an 

operator to reasonably expect to fill fuel tanks without spitback or spillage completely fails to 

take into account how different marine refueling is from other industry segments. For example, 

there are countless combinations of vehicles and trailers, which create numerous different fill 

angles. In addition, the need for an “open” system as well as specific installation locations for 

both fill and vent openings make an industry standard difficult to establish. Apart from the fuel 

system, there are a number of other variables that the boat builder cannot control that have a 

direct impact on whether the fuel system can perform automatic shutoff and reduce spitback and 

spillage. These challenges cannot be overcome by the boat builders alone. For example, the 

nozzles in use at marinas are not standardized nor are they equipped with an automatic shutoff 

feature. The unique fuel dispensing needs of boat fuel systems are another huge challenge. A 

gallon-per-minute (gpm) fuel dispensing restriction like that in place at retail gas stations to 

reduce spitback and spillage would not work for tanks that hold hundreds of gallons of fuel. EPA 

suggests a fill rate restriction between 5 to 20 gpm. A limit of 10 gpm, which is required at retail 

gas stations, would mean that a boat with a 300 gallon tank would have to wait 30 minutes to 

refuel. This is just not practical for refueling at a marina. 

NMMA chided EPA for incorrectly citing the ABYC standard for refueling and 

misstating its requirements (NMMA cited no specific errors and offered no corrections). 

NMMA also pointed out that EPA failed to mention that there is an ABYC technical committee 

currently working to address the technological issues associated with the H-24 standard and 

refueling practices. For all of these reasons, any requirements for refueling in the marine context 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

requires further analysis and discussion with ABYC to ensure the development of a 

comprehensive regulatory regime that addresses all the necessary parameters and variables. EPA 

must defer requirements addressing spitback and spillage until the necessary technological 

challenges can be resolved. NMMA recommends that ABYC be given three years to develop 

appropriate refueling standard practices and then provide industry with two model years of lead 

time for implementation. 

ABYC noted that vessel attitudes can vary dramatically during refueling and during operation, 

which increases that likelihood that liquid fuel will get into vent lines. Fill and vent openings on 

current boats must be located such that any fuel spilled, either from the filler neck or the vent, 

will not spill into the boat, which would create a grave fire and explosion hazard. Current 

recreational boats therefore are designed to route spills and overflows overboard, minimizing the 

fire and explosion risk (while contributing to water and atmospheric pollution). All these factors 

combine to make it impossible to simply adopt the automotive model in the marine market. 

ABYC is encouraging open and frank discussions among Project Technical Committees and 

comparable ISO Working Groups to develop a solution to spills caused by refueling or venting. 

This will be a long road and will likely result in substantive re-design of fuel systems to prevent 

and/or contain spills while still complying with established federal regulations. 

Sea Ray chimed in to say that EPA needs to recognize that standardization of fuel filler nozzles 

and fuel flow rates at marinas must be addressed before boat builders can design for compliance. 

Environmental Defense stated that EPA’s proposed requirement to produce vessels designed to 

prevent spills during refueling provide manufacturers with ample flexibility in choosing designs 

consistent with good engineering practices to reduce refueling and spillage emissions. Such 

design changes could include fuel inlets that allow consumers to see rising fuel levels during 

refueling and automatic shutoff devices. They support EPA’s proposal to reduce refueling 

spillage and spitback emissions as an important step in protecting human health and the 

environment. 

Inca Molded Products objected to the proposed regulatory provision related to preventing 

refueling emissions in §160.101(f)(3). There has not been time to evaluate the impact of this 

requirement to know what safety or performance issues might arise. Standardized nozzles and 

automatic shutoff would be necessary to implement for refueling controls can be implemented, 

and a 10 gallon-per-minute limit is not reasonable for marine vessels. It would also take time to 

design, test, and produce the components needed to address all the different penetration, 

attachment, and sealing techniques needed for the various vessel designs. Inca recommends that 

EPA give the ABYC and Inca at least three years to develop and test these systems, followed by 

a technical review. 

Attwood commented that the combinations of hulls, gunwale, and trailer designs, not to mention 

engine compartments and tank locations make it a monumental task to understand how each 

separate component plays into the boats fuel system design. Each item needs to be taken into 

consideration when designing the system and components to prevent fuel spillage and proper 

ventilation of the system to provide systems that fill without causing undue fuel spitback. 

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The chorus of boat builders largely reiterated NMMA’s position with respect to refueling 

controls. They included the following points: 

• ABYC has a technical committee established to address the issue of refueling. ABYC 

should be allowed three years to complete a refueling standard such that the controls 

could be applied to 2013 model year vessels. 

• Refueling control is a complex business. Variables include the refueling pumps, attitude 

of the vessel, and the vessel fuel system. A vessel's attitude is not under the control of the 

vessel manufacturer. The levelness of the trailer and the load size and distribution in the 

boat when it is in the water affects boat attitude. The resulting variation in attitude causes 

an incalculable number of possible fill angles. Additional factors include single vs. twin 

engines, two- and four-stroke engines, widely varying vessel sizes, and many option 

combinations and custom boats. Lowering fuel rates is not a solution because some fuel 

tanks are very large. 

• There are no current requirements for standardized nozzles or automatic shutoff at 

marinas today. These would need to be in place before ABYC is able to address the 

technical issues related to refueling and before boat builders can design for compliance. 

• Additional labor hours would be required to install the necessary hardware to control 

refueling and also greatly increase the number of potential fuel leaks at the various 

additional connections. Any system that depends on automatic shutoff is useless if there 

are refueling nozzles that do not have automatic shutoff. 

OPW and Husky, two prominent manufacturers for fuel nozzles, commented on the 

detailed specifications for standardizing marine nozzle dimensions. After some interaction 

regarding the optimal geometries for a standardized nozzle, they agreed that they could meet 

EPA specifications without changing their current product lineup if we would adopt 

specifications modeled after those for motor vehicle nozzles. The smaller-diameter nozzle 

would be capable of handling high flow rates (20 – 25 gallons per minute) that are sometimes 

seen at marinas. The “marine nozzle” would cost no more than nozzles that are used today. 

NMMA responded to the draft regulatory language by commenting that they believed 

EPA had not provided adequate opportunity to comment on the nozzle requirements, as required 

by the Administrative Procedures Act. They also noted that many of the marinas are small 

businesses, so a small business panel may be necessary before implementing these requirements. 

NMMA nevertheless stated its support for standardizing nozzles and upgrading marina fueling 

equipment, but preferred to do that in the context of the ABYC effort to adopt refueling 

standards. In any case, nozzle sizes should be smaller than 1.187 inches in diameter to avoid 

incompatibility with some vessels that are currently in use. NMMA emphasized that more 

information from marina owners and marine fuel system designers is needed before taking 

further action. 

Enviro-Fill added that they were working with two boat builders to prove out the 

technology for preventing refueling losses, and noted that the smaller-diameter nozzle would 

work well with their technology. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Letters: 

Commenter Document # 

NMMA 0688 

Sea Ray 0683 

Environmental Defense 0648 

Attwood 0653 

ABYC (hearing) 0642 

Enviro-Fill (hearing) 0642 

Enviro-Fill 0684 

Captain Aaron Kelly 0643 

Sea Ray 0683 

S2Yachts 0697 

Grady-White Boats 0677 

North American Sleekcraft 0666 

Triton 0656 

Lund Boat Co 0655 

Brunswick Corporation 0695 

Lowe Boats 0660 

Godfrey 0645 

American Marine Sports 0639 

Cigarette Racing 0637 

Massachusetts Marine Trade Association 0634 

Regulator Marine Inc. 0632 

Chaparral/Robalo Boats, Inc. 0630 

Ranger Boats 0628 

Larson/Glastron Boats 0626 

Four Winns Boats 0650 

Premier Marine Inc, 0613 

Skeeter 0706 

Yellowfin 0681 

Four Winns 0625 

OPW 0804 

Husky 0803 

NMMA 0805 

Enviro-Fill 0806 

Our Response: 

We appreciate the degree of interest in finding the best approach to reduce spitback and 

spillage from refueling vessels. This is clearly an issue that everyone understands to be very 

important. The best approach to ensure that refueling systems are properly designed would 

involve a standardized test procedure for boat builders to follow with an emission standard in 

place to determine when a design meets the required level of performance. The process of 

adopting such a standard would take considerable time, effort, and expense to ensure that the 

standard and the detailed test specifications are appropriately matched to the range of possible 

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Chapter 4: Evaporative Emissions 

design configurations and their achievable level of control. We do not have the time or resources 

to include such a plan in this rulemaking but plan to address this issue in the future. We expect 

to work with ABYC in this effort as they have initiated a process that would help to address this 

issue. 

However, we note from the comments that there is general agreement to adopt 

requirements now to standardize fuel nozzle geometries, while NMMA noted a preference to 

define nozzle geometries in the context of ABYC’s effort to establish an industry standard 

practice for boat builders. We believe it is not necessary to wait for development of standards 

for boat builders before we adopt a requirement applicable to marine refueling nozzles. Because 

regulating marine nozzle dimensions will reduce HC emissions during refueling, we are adopting 

the requirements related to marine refueling nozzle under Clean Air Act section 211(C). These 

requirements will help to reduce air pollution capable of endangering public health or welfare. 

These nozzle dimensions include the following: 

• Nominal outside diameter of 0.824±0.017 inches. 

• Straight with no holes or grooves, other than the aspirator hole, for at least 2.5 inches 

from the terminal end of the spout 

• Spring if used, to terminate at least 3.0 inches from the terminal end of the spout 

• Aspirator hole 0.670±0.05" from terminal end of the spout 

These specifications are identical to those already in place for motor vehicles, with the 

exception of the minimum diameter and the location of the aspirator hole. However, these 

dimensions are based on current practice with motor-vehicle nozzles (which includes 

specifications that go beyond EPA’s requirements), so we would expect most or all current 

gasoline nozzles to simultaneously meet the specifications for both motor vehicles and marine 

vessels. We may initiate a future rulemaking to merge these two separate specifications into a 

single specification that would apply universally for gasoline nozzles. We also believe that 

adopting these specifications now will better assist future efforts to address refueling emissions 

from vessels by defining a standard nozzle configuration, which we expect to be a necessary 

prerequisite for designing boats to prevent spitback and spillage. We also believe that adopting 

these specifications now will better assist future efforts to address the need for adopting 

provisions in the future to prevent spitback and spillage from marine vessels, as described above. 

Note that the nozzle requirements do not include a limitation on flow rate during 

refueling. If ABYC's analysis indicates that a limited flow rate is necessary as a reasonable 

boundary condition for designing fuel systems, we would consider including such a specification 

for maximum flow rate in a future rulemaking. Given the size of many marine fuel tanks, we 

agree that a restrictive maximum flow rate (below 20 gallons per minute or so) should be 

avoided if at all possible. 

We believe it is most appropriate to adopt the nozzle requirements “upon replacement.” 

Rather than having all marinas replace their nozzles by some date certain, we believe it will be 

most effective to adopt the requirement now so that any marina replacing a fuel nozzle must use 

a replacement nozzle that meets the new requirements. This minimizes the cost and disruption of 

the new requirement and puts the industry on a conversion plan that will generally align with the 

timing for implementation of future standards. Once this transition has started and there are 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

vessels that benefit from the standardized nozzle geometries, we would expect market forces to 

accelerate the conversion to the new nozzles. We would consider revising the nozzle regulation 

to require conversion to the new nozzles by some date certain if it becomes clear that this is 

necessary to facilitate effective controls resulting from the effort to adopt uniform industry 

practices for boat designs that minimize refueling losses. 

Pending development of any further detailed specifications for designing and testing 

boats, we believe it is appropriate for us to keep the proposed provision requiring boat builders to 

follow good engineering practice to allow for a reasonable expectation that operators can expect 

to fill the fuel tank without spitback or spillage. We would expect boat builders to at least take 

the minimal steps noted in the proposal to avoid designs that virtually ensure that normal 

refueling procedures would lead to spillage. For example, running a filler neck to the side of a 

boat with a substantial horizontal segment at the inlet makes it very difficult to execute a clean 

refueling event. If an industry standard is adopted, “good engineering practice” would include 

following the industry standard unless EPA believes such a standard is inadequate. 

We believe our proposed rule fairly apprised commenters of the issues related to nozzle 

requirements. We requested comment on detailed specifications on nozzle dimensions in the 

proposal. We received a very extensive set of comments during the comment period, some 

supporting the adoption of nozzle requirements and some objecting. We made draft regulatory 

language available in the rulemaking docket and sent that draft directly to the parties most 

affected and most able to further communicate that information to additional affected parties. 

We also received comment on this later request for feedback. The final requirements are 

consistent with the discussion in the proposed rule and with the concepts already in place for 

motor vehicles. In addition, nozzle manufacturers commented that they can meet the new 

requirements with no change in their current product lineup. As a result, the impact on marinas 

is a limitation on the nozzle choices they have available. We also understand the nozzle 

manufacturers’ statements to be clearly responsive to Inca’s concern that there is a need to 

evaluate the impact of the new requirement to verify that there will be no safety or performance 

issues. We would not expect boat builders to change their designs to accommodate the 

compliant nozzles because such nozzles are in common use today. Based on information from 

nozzle manufacturers, replacement nozzles will not cost more due to this requirement than they 

would without it; but there will not be an option to choose from the selection of nozzles that have 

been available previously. Since there is minimal to no impact on small businesses due to these 

nozzle requirements, we are certifying that the final rule will not have a significant impact on a 

substantial number of small entities and EPA has complied with requirements for convening a 

small business advocacy review panel pursuant to section 609(b) of the Regulatory Flexibility 

Act. 

4.5.2 Refueling– Small SI 

What Commenters Said: 

OPEI and EMA commented the proposed refueling requirement lacks the necessary 

defined acceptance criteria necessary to be implemented as a regulatory requirement. As such, 

OPEI and EMA believe the requirement cannot be included in the regulatory requirements and 

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Chapter 4: Evaporative Emissions 

should be deleted. However, the information provided is valid reference material for future 

designs and is more appropriately included in the regulatory preamble. If EPA must keep the 

requirement in this regulation, OPEI commented that EPA should modify the language to ensure 

there is no conflict with existing applicable ANSI, ISO or EN standards that specify opening 

sizes. 

Environmental Defense noted that gasoline vapors are always present in typical fuel 

tanks. These vapors automatically are released during refueling as gas inserted into the tank 

forces out the evaporative vapors from remaining tank space. Fuel spills also occur from Small 

SI and Marine SI engines during refueling. In the case of marine boats, “relatively large 

quantities of gasoline are released into the marine environment during marine refueling events.” 

Accordingly, controlling spills during refueling is important for public health and the 

environment. Environmental Defense noted that EPA is proposing equipment design changes to 

reduce spills during refueling of both SI small and marine engines and equipment. These design 

changes provide manufacturers with ample flexibility in choosing designs consistent with good 

engineering practices to reduce refueling and spillage emissions. Such design changes could 

include fuel inlets that allow consumers to see rising fuel levels during refueling and automatic 

shutoff devices. Environmental Defense supported EPA’s proposal to reduce refueling spillage 

and spitback emissions as an important step in protecting human health and the environment. 

Letters: 

Commenter Document # 

OPEI 0675 

Environmental Defense 0648 

EMA 0691 

Our Response: 

EPA and engine and equipment manufacturers have long agreed that refueling emissions 

are a substantial source of emissions. It has also been clear that it is very difficult to address 

refueling losses through regulatory requirements since spill-free refueling depends on a 

combination of several factors related to design of the engine, the design of the equipment, the 

design of the refueling container, and (not least) the refueling procedures used by millions of 

owners. Now that exhaust and permeation emissions are on track to reach much lower levels, 

spillage becomes an ever more important contribution to overall emissions from Small SI 

engines and equipment. 

Our normal approach would be to adopt a test procedure and a corresponding standard so 

manufacturers would design and produce their products such that they prevent emissions by 

virtue of their design features, much like we describe above for marine applications. However, 

Small SI equipment models generally have very simple fuel systems that do not lend themselves 

to design features for preventing spillage. We recently adopted a requirement for refueling 

containers (i.e., gas cans) very similar to what we proposed in this rulemaking (72 FR 8428, 

February 26, 2007)). 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

We agree with the commenters that the proposed refueling requirements do not include 

defined criteria for evaluating whether or not the designs are compliant. Nevertheless, we 

believe it is meaningful and workable to adopt a good-engineering standard for Small SI 

equipment that corresponds to the provisions that already apply for gas cans. Furthermore, we 

believe it is reasonable to specify that manufacturers should be able to design their engines and 

equipment such that operators can reasonably expect to fill a fuel tank without fuel overflow. 

Many equipment designs today would meet this requirement. For example, riding lawn mowers 

typically have 2-inch or 3-inch diameter openings for refueling that are located in a place with 

easy access and good visibility. Smaller equipment with smaller fuel tanks generally have 

smaller openings for refueling, but we would want to differentiate those designs with a big 

enough opening to allow for seeing the fuel level and a ready enough access with a refueling 

spout to avoid spillage in positioning the gas can. Gas cans come with a standard spout diameter 

of 3/4 inch. This should allow for engine and equipment manufacturers to design their systems 

to allow for a sufficient margin to prevent an unavoidably awkward procedure to fill the fuel 

tank. As an example, we would consider a design deficient if it required the operator to use a 

funnel to properly position the spout from a typical gas can to consistently deliver fuel into the 

fuel tank. 

We agree that any published industry standards addressing equipment designs related to 

refueling would be sufficient for purposes of implementing the proposed requirement. 

Specifically, we would not insist that manufacturers go beyond current industry standards to 

meet our requirements. For example, we are aware of ANSI standards that specify standard 

dimensions for fuel tanks on chainsaws. We have revised the regulation to take this into account. 

Manufacturers also raised a concern in discussions after the proposal that operators may 

attempt to refuel with a gas can that is too big. For example, filling a string trimmer’s fuel tank 

with a five-gallon container would be awkward and difficult to perform without spilling even if 

the string trimmer were appropriately designed given the constraint of the size of the fuel tank. 

We have revised the regulation to specify that the expectation for proper refueling is limited to 

refueling events with an appropriately sized gas can. 

4.5.3 Fittings and connectors 

What Commenters Said: 

California ARB commented that carburetor and connector emissions could be controlled 

by available technology. 

Letters: 

Commenter Document # 

California ARB 0682 

Our Response: 

We proposed a requirement in §1060.101(f) that manufacturers design fittings and 

connectors to ensure secure connections that prevent leakage. We did not propose a separate 

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requirement that fittings and connectors be made of low-permeation materials. We believe the 

emissions resulting from permeation through these parts of the fuel system with very small 

surface area exposed to fuel will not be great enough to warrant separate testing and certification. 

As we learn more about low-permeation technologies and gain experience with overseeing 

evaporative standards for nonroad equipment, we may consider whether it is necessary or 

appropriate to include such a requirement in a later rulemaking. 

4.5.4 Tethered and self-sealing fuel caps 

What Commenters Said: 

NMMA and Mercury Marine noted that in §1060.101(f), EPA proposed requirements 

that would apply to equipment manufacturers whether or not they are subject to and certify to 

any of the evaporative emissions standards in §§ 1060.102 or 1060.105. If these requirements 

are met, equipment manufacturers will be “deemed to be certified” as conforming with the 

requirements without having to submit a certification application. NMMA and Mercury Marine 

supported the first requirement for fuel caps in §1060.101(f)(1)(i), which includes the 

requirement that fuel caps for equipment subject to diurnal requirements must include a visual or 

audible indication of when the cap is properly sealed. The added flexibility of being able to use 

either a visual or audible indication is helpful and recognizes that either approach will be able to 

signify that the cap is sealing the tank. 

Since caps with automatic vents, tethers, and audible or visual indicators of being sealed 

do not exist, currently, for marine tanks, Mercury Marine requested that this requirement not be 

implemented before 2010. Mercury Marine commented that design, development, testing and 

validation to meet these requirements will take 18 to 24 months. 

EMA commented that in order to provide necessary alignment with California ARB 

requirements, the second sentence of §1060.101(f)(1)(i) should be revised to read as follows: 

“Fuel caps for equipment subject to diurnal requirements must include physical and/or audible 

feedback to the user indicating when it is properly sealed.” 

IMPCO and Protectoseal submitted comments on the sealing requirements for gas caps 

on Large SI engines and equipment. See Section 1.8.2 for those comments and our response. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

EMA 0691 

Our Response: 

The requirement to include tethered fuel caps with sealing indicators does not take effect for 

Marine SI vessels until there is a diurnal standard. These standards start to apply in 2010 for 

portable marine fuel tanks and personal watercraft. The diurnal standards start in July 2011 for 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

other vessels (and outboard engines) with installed fuel tanks. Vessels that are exempted from 

the diurnal emission standards for the first one or two years of the new standards are also exempt 

from the tethering and sealing requirement. Implementation of these requirements therefore fits 

with the development timeline suggested by Mercury. 

We agree that it would be appropriate to specify a “physical” indication of a sealed fuel 

cap in addition to visual or audible indicators. We have revised the regulations accordingly. 

4.5.5 Keeping water out of evaporative canisters 

What Commenters Said: 

EMA commented on §1060.101(f)(1)(iii) “What evaporative emission requirements 

apply under this part?” EMA commented that while this section requires carbon canisters to be 

installed such that they will not be exposed to water or liquid fuel, it fails to establish the criteria 

for determining what EPA will consider an acceptable design to preclude exposure to water or 

liquid fuel. EMA commented that such criteria should either be included in the final rule or 

addressed in subsequent guidance. 

Letters: 

Commenter Document # 

EMA 0691 

Our Response: 

Designing systems to prevent flow of liquids into carbon canisters is achievable with simple 

and well established technologies. This requirement does not relate to exposing canisters to 

humid air that may be approaching the dewpoint. A straightforward engineering demonstration 

would be sufficient to show that water or liquid fuel will not reach the canister. Since this 

requirement applies to companies that will generally not be submitting an application for 

certification, this requirement does not involve EPA approval. 

4.6 Labeling equipment, vessels, and fuel-system components 

4.6.1 Labeling fuel lines, fuel tanks, and other fuel-system components 

What Commenters Said: 

NMMA and Mercury Marine noted that the evaporative emissions provisions require 

labeling of the fuel lines, fuel tanks, and other emission-related components in §§ 1060.135 

through 1060.138. One of the greatest concerns NMMA and Mercury Marine have with the 

proposed evaporative emissions labeling requirements is the requirement to include EPA’s 

standardized designation for the emission family. This requirement is contained in 

§1060.136(a)(3), §1060.137(b)(2), and §1060.138(b)(2). NMMA and Mercury Marine 

commented that to include the standardized designation for the emission family places a large 

burden on component and vessel manufacturers. These businesses must already comply with a 

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whole host of labeling/certification requirements. NMMA and Mercury Marine urged EPA to 

move to a universal label that will simplify the administrative burden placed on the marine 

industry. They noted that ABYC and NMMA have developed in H-24 and in SAE J1527 

uniform language and markings that include all the necessary information and which satisfy the 

USCG requirements as well as those imposed by California ARB. Both of these standards were 

recently revised at the request of EPA to reflect low permeation hoses. NMMA and Mercury 

Marine believe that the uniform language in H-24 and SAE J1527 for fuel lines makes the most 

sense for this industry. NMMA commented that EPA should also adopt for fuel tank labels the 

uniform language recommended in ABYC H-24. 

NMMA commented that another way for EPA to reduce the regulatory burden associated 

with the labeling requirements for hoses is to allow for use of hoses certified to other EPA 

standards. In the past, NMMA has raised with EPA the importance of including in this rule the 

ability to use hoses that are labeled for purposes of complying with the Recreational Vehicle 

Rule. This type of flexibility makes sense for manufacturers that produce products for both 

markets and reduces the compliance burden without impacting emissions reductions. 

Sea Ray commented that a universal label would help to minimize the administrative 

burden for of labeling. Sea Ray encouraged EPA to work with ABYC and NMMA to approve a 

universal label. 

OPEI and EMA commented that the evaporative labeling requirements should be 

dramatically simplified to respond to both space constraints and common industry practices for 

identification of manufacturer and construction. Specific requirements to include EPA emission 

family and FELs are not viable or practical. OPEI noted that California ARB does not require 

evaporative FELs to be placed on the emission label. EPA’s proposal to add individual 

evaporative FELs on the label would be inconsistent with California ARB, would further confuse 

consumers, and would be totally impractical for manufacturers. OPEI and EMA commented that 

EPA should drop completely its proposed evaporative FEL labeling requirement. 

OPEI and EMA recommended that the regulatory requirement specify that the 

evaporative components be labeled such that the Agency, the equipment manufacturer, the 

engine manufacturer, or any other interested party can logically locate the EPA Certificate of 

Conformity information. Anything beyond the component manufacturer’s designation that can 

be traced to EPA certification documentation is redundant and should be avoided. For example, 

fuel tank labeling should include the manufacturer name or trademark and a product 

identification that allows identification of the applicable Certificate of Conformity. This may 

include a part number or series number that is identified in the applicable application for 

certification, and a date of manufacture code. 

OPEI commented that handheld engines are integrated equipment and should be allowed 

to use the California ARB labeling method for harmonization purposes. Fuel tanks and fuel line 

should be labeled with an ID mark that can be traced back to the emission application for 

confirmation purposes. OPEI commented that labeling the individual components with 

statements, FEL, and family names is not always possible. 

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OPEI commented that language needs to be added to §1060.138 that allows the 

information required on the fuel cap to be molded in. 

EMA commented that the requirements set forth in §90.127(a)(5)(ii) are confusing. 

EMA noted that the section indicates that the fuel line permeation level must be included on the 

label in addition to the certificate holder or fuel line manufacturer’s corporate name or 

trademark. However, the example would allow use of SAE classification. 

EMA commented that the repeating period of 12 inches on fuel lines is typical in industry 

and should be maintained. Regardless of the desire to assure the ability to confirm identification 

there are products that require fuel lines that are extremely short and could not practically 

include the identification on every piece. EMA commented that if there is a question of 

compliance, EPA should inspect several units to provide assurance that short lines contain, in 

aggregate, identification of compliance. 

EMA and MIC noted that the proposed regulation incorrectly references §1060.135(e) in 

several places to identify the provision related to alternate labeling. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury Marine 0693 

Sea Ray 0683 

MIC 0701 

OPEI 0675 

EMA 0691 

Our Response: 

We agree with the commenters that a streamlined approach for labeling fuel-system 

components is appropriate. We have developed an alternate protocol with very simple label 

information that would allow for looking up all the relevant certification information in our 

database. We believe the label information should do three things: (1) identify that the code 

relates to emission standards, (2) identify the certifying manufacturer, and (3) identify the 

certified emission family. This code could be perhaps nine characters in length. For example: 

“EPA: ABCXYZ” would (1) identify the hose as compliant with EPA regulations, (2) identify 

the manufacturer as ABC (generally based on the manufacturer abbreviation assigned by EPA), 

and (3) identify the family as XYZ. Since the manufacturer is identified in the label information, 

the family identification code can be determined by the manufacturer without the risk that a 

different manufacturer would use the same code. This shortened labeling protocol applies 

equally to fuel lines, fuel tanks, and other certified fuel-system components. 

This approach should allow manufacturers to label their products consistent with industry 

standards. The detailed provisions in the final rule may require some additional characters, but it 

remains very short and allows for the coded approach favored by the industry. 

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We believe manufacturers should have the option of including the more detailed 

information on fuel-system components if they would rather not develop the code names for their 

emission families. For example, we are aware that straight-run fuel lines are commonly labeled 

with a continuous printing that includes extensive information. Similarly, fuel tanks are already 

produced with labeling information incorporated into the mold. If manufacturers want to take 

this approach, we would welcome that. 

We agree that harmonized standards and labeling requirements across EPA programs is 

beneficial. The emission standards and test procedures in this final rule are consistent with those 

that already apply for recreational vehicles. The labeling regulations for recreational vehicles do 

not include any specific requirements. We would therefore agree that any fuel tanks or fuel lines 

that are properly labeled under part 1060 would be suitable for use in recreational vehicles. We 

intend in the future to broaden the scope of part 1060 to include recreational vehicles, with any 

appropriate modifications to reflect the unique situation for those applications. We believe this 

is the best way to maintain a consistent approach across programs. 

It is important for equipment manufacturers and EPA inspectors to be able to readily 

establish the applicable Family Emission Limit for any particular fuel tank. We agree, however, 

that the FEL can be omitted from the label under the streamlined labeling approach described 

above, since the label code could be used to look up the family information, including the FEL. 

This is possible because we require fuel-tank manufacturers to recertify a fuel tank if they 

change the FEL. Changing the FEL without recertifying the emission family would lead to 

confusion, since the database would not readily associate a single FEL with each family code. 

For manufacturers choosing to include the more detailed label information on their fuel tank, we 

are specifying that the FEL should be part of the included information. Without the code for 

looking up certification data, equipment manufacturers and EPA inspectors would otherwise not 

be prompted to know that an FEL applies for any particular fuel tank. 

We are including the proposed requirement to label fuel lines with continuous 

information, repeating at least every 12 inches (except for short segments), with one 

modification. The shortened labeling approach we are allowing for the final rule does not lend 

itself as well to continuous repeating. We are therefore revising the regulation to specify that 

this code must be repeated such that the blank space between repeated label information must be 

no longer than the code itself. We understand that this approach to labeling for short fuel-line 

segments may involve individual pieces that do not include a complete set of labeling 

information. We agree with the commenter that inspection of multiple fuel lines associated with 

an engine would be an appropriate way of evaluating these products. 

We agree that fuel caps and other components besides the fuel tank may be properly 

labeled by molding the label content with the part. We have revised the regulation to specifically 

allow this. 

We have corrected the references to the alternate labeling provisions in §1060.135. 

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4.6.2 Labeling equipment and vessels 

What Commenters Said: 

OPEI commented that to create a practical, efficient program and provide greater 

harmonization with California ARB, EPA should finalize –as an alternative compliance path – an 

integrated and holistic evaporative compliance approval process. This process should explicitly 

provide for a single evaporative and exhaust certification application, an integrated label, and an 

inclusive warranty statement consistent with California ARB’s approach. For example, for 

engines or equipment using a single label for both exhaust and evaporative compliance, the 

emission compliance label language should be combined to read "This engine complies with 

U.S. EPA EXH/EVP STDS.” The engine or equipment manufacturer that is responsible for the 

introduction into commerce of the complete evaporative control system required by this part 

should label the engine/equipment. The label should simply include the following information: 

1) Corporate name or trademark; 2) Date of manufacture [month and year] unless it is stamped or 

engraved elsewhere on the engine/equipment; and 3) Statement of compliance; i.e., "this 

equipment complies with U.S. EPA evap. Stds." 

OPEI commented that the requirement to add a statement about using credits to certify 

(see §1060.135(b)(2)(iv)) is not used for exhaust certification labels today. Such a requirement 

is not justified, serves no purpose to consumers and is an unnecessary burden and therefore 

should be deleted. When EPA inspectors need this info, they can get it from their own 

certification website. 

EMA commented regarding §1060.135(b)(2) that whether a product generates or uses 

credits should not be included in labeling. EMA noted that ABT information is available in the 

certification application documents. Including this information on the label serves no purpose, 

and would take up unnecessary space on a very small and crowded label. 

EMA commented that the proposed labeling requirements in §1060.135(b)(1) are not 

feasible. The engine or equipment manufacturer that is responsible for introducing into 

commerce the complete evaporative control system required by this part should be required to 

provide the emission compliance label for the engine/equipment. The emission compliance label 

should only be required to include the following information: 

(i) Corporate name or trademark 

(ii) Date of manufacture [month and year] unless it is stamped or engraved elsewhere on the 

engine/equipment 

(iii) Statement of compliance; i.e., “This equipment complies with U.S. EPA evap. stds.” 

For engines or equipment using a single label for both exhaust and evaporative compliance, 

the statement of compliance would read “This engine complies with U.S. EPA EXH/EVP 

STDS.” 

Briggs and Stratton commented that the labeling requirements for engines and 

components needs to be simplified and harmonized significantly from what is in the proposal. A 

lot of unnecessary and impractical requirements are proposed which add no benefit but a lot of 

cost and effort for manufacturers. 

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Honda commented that in the case where a single manufacturer is certifying and building 

the complete assembly, there should be no requirement to label components as specified in 

§§1060.136 through 1060.138. Honda requested that if an engine manufacturer chooses to 

certify a complete fuel system, that a single emission label for exhaust and evaporative standards 

compliance be allowed. Purchasing fuel tanks that are designed, manufactured and certified by a 

third party is not the only way an equipment manufacturer or engine manufacturer builds a 

product. In fact, it is uncommon, other than for portable and some larger marine fuel tanks, that 

a manufacturer will use a generic or third party fuel tank. It is much more common for the 

equipment or engine manufacturer to outsource the manufacture of the fuel tank based on its own 

tooling and design. This is also true for fuel lines, especially molded fuel lines that are required 

for the confined spaces and challenging routing for many engines and equipment. Honda 

suggested that the final rule should recognize that there can be one certifying entity for a 

complete fuel system or that the system can be assembled as a combination of certified parts by 

any combination of certifying entities. 

Honda commented on §1060.135(b) with regard to OB/PWC labeling. Honda 

recommended that a simplified statement be used on the single label stating only that the 

outboard engine or the PWC complies with the evaporative requirement. Since there is already a 

compliance statement this could be accomplished by adding the word evaporative or better the 

abbreviation “evap”. Actually, an even simpler statement is possible. Because the regulation 

requires both exhaust and evaporative compliance the label could simply state compliance with 

the requirements for the applicable model year i.e., THIS ENGINE COMPLIES WITH U.S. 

EPA REGULATION FOR (MY) SPARK IGNITION MARINE ENGINES. 

Boat builders belonging to NMMA commented on the labeling requirements. They 

commented that the proposed labeling regulations are vague and confusing. They commented 

that EPA needs to simplify the requirements and should work with NMMA and ABYC to create 

universal compliance label and location, such as on the hull. The boat builders noted that ABYC 

and NMMA are working on developing a universal label that will include all information and 

would like to work with EPA. 

NMMA included later comments to suggest label language that states: "This boat 

complies with EPA evaporative emission requirements in place at the time of construction". 

This label would be located on the helm and would follow the USCG required language that 

states that the vessel is in compliance with their regulations. They included pictures showing 

labels required by Coast Guard. In addition, NMMA requires that their members add a 

certification plate at the vessel’s helm. NMMA recommended that we allow boat builders to 

combine these various labels and suggested that we require all such labels to be visible from the 

helm of the vessel. 

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Letters: 

Commenter Document # 

Yellowfin 0681 

Honda 0705 

OPEI 0675 

Briggs and Stratton 0657 

EMA 0691 

Sea Ray 0683 

S2Yachts 0697 

Grady-White Boats 0677 

North American Sleekcraft 0666 

Triton 0656 

Brunswick Corporation 0695 

Lowe Boats 0660 

Godfrey 0645 

American Marine Sports 0639 

Cigarette Racing 0637 

Regal Marine Industry 0635 

Massachusetts Marine Trade Association 0634 

Regulator Marine Inc. 0632 

Ranger Boats 0628 

Larson/Glastron Boats 0626 

Four Winns Boats 0650 

Hallett 0713 

Skeeter 0706 

NMMA 0790 

Our Response: 

We agree with the commenters that the evaporative labeling requirements for equipment 

should be simplified and better aligned with the requirements adopted by California ARB. For 

equipment that is produced using only certified components (i.e., certified by companies other 

than the equipment manufacturer), the final rule specifies that the label include only the 

manufacturer’s name and a simple statement that the equipment uses certified components. For 

certifying equipment manufacturers, we also require the date of manufacture to be on the label 

(or permanently identified elsewhere on the equipment), and coded information to identify the 

various certified components. This may take the form of a single code that allows us to look up 

all the part information in the manufacturer’s application for certification, or manufacturers may 

identify the individual components. For manufacturers that certify with respect to both exhaust 

and evaporative emissions, this code could be the engine family name used for compliance with 

exhaust standards. We would expect many equipment models to use only two certified 

components (fuel tank and fuel line), though other models might have include multiple fuel tanks 

or fuel lines from different emission families. Being able to access information related to 

certified components will be very helpful for inspectors to establish whether an individual piece 

of equipment complies with the regulations. 

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This approach includes specifications that are nearly identical to those adopted by 

California ARB. Where we specify additional detail, we believe there will be a minimal burden 

to make the label more prescriptive or more informative than California ARB requires. We 

would also expect California ARB to consider revising its requirements to complete the effort to 

harmonize federal and state requirements. 

We agree the manufacturers do not need to separately identify equipment that generates 

or uses emission credits. Identifying the certified components and the emission family name for 

the equipment (if applicable) should allow EPA or Customs inspectors to identify whether the 

equipment complies with regulations or not. 

We also agree that manufacturers certifying with respect to both exhaust and evaporative 

emissions should be able to combine information into a single label. In fact, this would be 

preferred for EPA’s purposes, since all the relevant information would be presented together. 

We have included in the final regulation NMMA’s suggestion to require vessel labels to 

be visible from the helm. This labeling content may also be combined with other required 

labeling information, such as labels required by Coast Guard. 

4.7 Certification and compliance issues 

4.7.1 Useful Life 

What Commenters Said: 

OPEI and EMA commented that the proposed lead time is not sufficient to allow 

confirmation of the EPA proposed useful life period of five years. OPEI and EMA suggested a 

two-year useful life requirement for all evaporative standards. If necessary, they noted that a 

longer durability period should be the subject of a subsequent rulemaking. OPEI similarly 

commented that EPA should restrict the useful life requirements for handheld fuel lines in the 

first three years of the standard to two years instead of five, because there will be no opportunity 

to verify longer useful life of the uniquely handheld equipment solutions before the first lowpermeation fuel lines go into production. 

EMA commented that the default maximum calendar time for required compliance of 5 

years for exhaust and 2 years for evaporative must be included in the definition of useful life in 

§1054.801. Accordingly, EMA suggested the useful life definition should be revised as follows: 

“...degree of service accumulation can be verified separately or the engine/equipment have 

exceeded the required compliance calendar period.” 

EMA noted that useful life for evaporative controls is addressed in §1060.101(g) and 

§1054.145. EMA commented that EPA should combine all useful life discussion into one 

section. 

Promens commented that under §1045.145(d) and §1054.145(g) an interim provision is 

being offered for a limited time of two years for Marine SI and Small SI fuel tanks through 2013 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

to allow manufacturers to gain experience. This provision is greeted with open arms but does 

not give the fuel tank manufacturers enough in-field use experience as might be expected. 

Promens noted that a typical marine fuel tank may be manufactured in March, is shipped and 

stored at the boat manufacturer for up to 3 months then installed into the vessel. The vessel is 

stored as a finished product at the boat manufacturer for 1 to 2 months, is shipped to a dealership 

and then sits in storage for as long as 6 months until it is sold at the retail level. A typical 

scenario may place the tank from date of manufacture to end user in 4 to 11 months. This lowers 

the in-field experience level down to only a little over one year. Promens noted that many boat 

owners use their boats only on weekends and only for 3 to 5 months of the year. Therefore, true 

in field use could be reduced to as little as a 3 to 6 month timeframe in the two years provided by 

this provision. Promens requested that this provision be extended to three years to provide a true 

measure of at least two working seasons. 

Letters: 

Commenter Document # 

EMA 0691 

OPEI 0675 

Promens (Hearing) 0642 

Our Response: 

Emission standards are meaningful only to the extent they ensure emission reductions 

over the period that equipment is properly maintained and used. We believe there are emission 

control technologies already available to achieve most of the new emission standards and there 

has been time to establish the necessary durability of the products. In some cases, manufacturers 

are working toward commercializing technologies that have been under development more 

recently. In these cases too, we would expect manufacturers to factor durability into the design 

effort to ensure that products will meet emission standards over five years of normal use. 

Manufacturers provided no basis for claiming that it was possible to comply over a useful life 

period of two years but not five years. However, to ensure that manufacturers have some 

opportunity to take steps to confirm the durability of permeation controls for fuel tanks and coldweather fuel lines, we are adopting a two-year useful life for model years before 2014. We also 

note that the permeation standards were first proposed in 2001 for Marine SI vessels and in 2007 

for Small SI equipment. These several years of lead time should allow manufacturers ample 

opportunity to confirm that technologies are durable, including any need to adjust product 

specifications or production processes to comply. 

It is not necessary to include the additional text to the definition of useful life, as 

recommended by EMA. The definition already references the appropriate cites to illustrate 

which useful life periods apply. 

We intend for §1060.101 to include a general framework for establishing useful life. The 

interim provisions for a shorter useful life in §1054.145 are limited to Small SI engines and 

equipment and will have no relevance after 2013. We therefore believe it is unnecessary to add 

that as clutter to the long-term provisions in §1060.101. 

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4.7.2 Division of responsibilities for component manufacturers, engine manufacturers, 

and equipment/vessel manufacturers 

What Commenters Said: 

EMA noted that the NPRM properly recognized that evaporative emission control of 

Small SI engines and the equipment these engines power may involve the engine manufacturer, 

the equipment manufacturer, or the component supplier. Accordingly, EMA supports the overall 

framework of the NPRM, and urged EPA to finalize a rule that preserves that framework in order 

to maintain the feasibility of the pending rulemaking. 

EMA commented that the complex multi-level, disaggregated nature of the industry’s 

structure makes it impossible to impose the evaporative emission control requirements on either 

the engine manufacturer or the equipment manufacturer exclusively. For example, EMA noted 

that the highest volume engine/product category affected by the NPRM is walk-behind 

lawnmowers. In the case of such lawnmowers, the engine manufacturer generally provides the 

equipment manufacturer with a complete, compliant product that complies with all regulatory 

requirements (including both exhaust and evaporative emission controls). In such a scenario, all 

regulatory compliance, emission warranty, and other requirements typically are the sole 

responsibility of the engine manufacturer. In addition, California requires such engines to 

comply with performance-based standards that require testing using a SHED. In contrast, EMA 

noted that the lowest volume products covered by the NPRM are produced by equipment 

manufacturers that utilize “standard” engines purchased through a distribution network. In those 

cases, the engine manufacturer typically has no direct relationship with the equipment 

manufacturer. Due to the structure of the industry, EMA commented that the flexibility 

proposed in the NPRM is absolutely necessary in order to allow alternate means for the 

production of compliant engines and equipment. Accordingly, it is crucial that such flexibility 

be maintained in the final rule. 

EMA commented that it is not appropriate or practical for equipment manufacturers that 

are using engines certified to the exhaust standard provisions by their engine supplier to include 

information regarding exhaust standard compliance. Engines certified for use with equipment 

manufacturer supplied fuel tanks will include the required interface features to allow the 

equipment manufacturer to install engines into equipment with the running loss controls in place 

without modification to the engine. EMA commented that equipment manufacturer 

modifications to engines certified by the engine manufacturer should be considered tampering, 

unless the modification is contractually agreed to by the engine and equipment manufacturer. 

Honda recommended that EPA implement the necessary steps to accept SHED-tested 

engines and equipment as an option to component certification throughout the Phase 3 

regulation. Engines and equipment that have evaporative emission certification granted by 

California ARB, based on SHED testing and meeting the running loss control requirements, will 

exceed the EPA emission reduction standards. For this reason, Honda commented that these 

engines and equipment should be granted an EPA certificate based on the test data upon which 

the California ARB certification is based. Honda appreciates that EPA has provided the option 

to use the California ARB certification, regardless of the actual parts used to comply with the 

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SHED standard, to demonstrate compliance with the early fuel line requirement and the 

transition period implementation of additional controls. Similarly, Honda noted that EPA 

acceptance of this testing option will allow them to sell their products in all 50 states. This 

harmonization is beneficial to the environment and economy of all parties involved, from 

suppliers in the production cycle to the final user of the product, and would be applicable both 

near term during the regulatory transition phase and beyond 2013. 

The RV Industry Association noted that with respect to towable RVs, there are more than 

50 manufacturers producing many hundred different RV models and floor plans. Total industrywide production of towable RVs in 2006 exceeded 334,600 units. Given the proposal’s 

requirement that certifications be filed for each applicable model, along with the staggering 

number of potentially affected models produced by RV manufacturers, they believe that the 

proposed certification requirements will inundate the agency with thousands of certification 

submissions annually from the RV industry alone. The RV Industry Association commented that 

this reality suggests changes to the proposed certification requirements need to be considered. If 

the end goal is to develop a regulation that provides for enhanced control over evaporative 

emissions from generator fuel systems without unnecessarily burdening government and 

industry, EPA should consider emulating the approach adopted by California ARB in 2005 for 

its Small Off Road Engine (SORE) regulation. Under that regulation, if a RV manufacturer 

utilizes only fuel system components specified by the manufacturer of the generator (who has 

itself obtained an Executive Order from California ARB), then there is no up-front certification 

burden on the RV manufacturer. Conversely, if any RV manufacturer elects not to use the 

components specified by the generator manufacturer, it then becomes the responsibility of that 

RV manufacturer to certify to California ARB that the generator fuel system complies with the 

applicable requirements. 

Briggs and Stratton commented that when an equipment manufacturer certifies for 

evaporative emissions it is not clear if the certified components used (fuel tank, fuel cap (if 

separate), fuel line, and carbon canister) are combined into an application. Briggs and Stratton 

commented that this issue needs to be clarified so that one manufacturer (the engine or 

equipment manufacturer as applicable) gets a combined certificate for the product. It appears 

that the way the NPRM is written each component manufacturer is responsible for labeling, 

warranty, etc. for each component. Briggs and Stratton commented that this is not a practical 

way to manage the emissions certification process. 

EMA commented that the proposal does not appear to allow a manufacturer responsible 

for both the exhaust and evaporative emission requirements to submit a single certification 

application and obtain a single Certificate of Conformity for compliance with both requirements. 

Engine manufacturers that produce fully integrated engines, such as walk behind mower engines 

and many handheld products, should be provided the opportunity to submit one application and 

obtain a single Certificate for their products. In addition, §1054.201(a) states that a manufacturer 

certifying to both exhaust and evaporative emission requirements must submit separate 

applications. If finalized, EMA believes this requirement would preclude a manufacturer from 

combining documentation, labeling, and other features that could result in a significant reduction 

in paperwork and lower potential for errors. EMA commented that manufacturers should be 

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Chapter 4: Evaporative Emissions 

given the opportunity to combine exhaust and evaporative certification submissions and obtain a 

single Certificate of Conformity at their discretion. 

EMA commented that §1054.205(o)(2) is inconsistent with the requirement to segregate 

exhaust and evaporative certification submissions as proposed under §1054.201(a). EMA 

believes manufacturers should be allowed to submit a combined exhaust and evaporative 

application. EMA commented that if their recommended revisions to §1054.201(a) were 

implemented, then §1054.205(o)(2) is acceptable. However, if their recommended revisions are 

not implemented, EMA commented that §1054.205(o)(2) must be deleted. 

EMA noted that the first sentence of §1054.2 refers to manufacturers of engine and fuelsystem components as described in §1054.1. However, §1054.1 does not describe engine and 

fuel system component manufacturers. The last sentence of this section states that equipment 

manufacturers are generally responsible for evaporative emissions. However, the evaporative 

emission control requirements described in Part 1054 are generally applicable to engine 

manufacturers (equipment manufacturer requirements are identified in Part 1060). EMA 

commented that this section must be revised so that it accurately identifies the industry to which 

the regulatory sections (1054 or 1060) apply. 

EMA commented that the proposed language in §1060.5(e)(2) is confusing and must be 

clarified. EMA recommended that the first sentence be revised to read as follows: “Engine and 

equipment manufacturers that produce handheld Small SI engines/equipment must certify their 

engines and fuel systems under 40 CFR Part 1054. However, they must certify...” 

EMA noted that as proposed, §1060.5(e)(1) would require the component manufacturer 

to certify fuel lines and fuel tanks, except as allowed by §1060.601. However, §1060.601(f) 

does not require the component manufacturer to certify fuel lines and tanks, but rather gives 

them the option to do so. EMA commented that this section should be revised to identify this 

option and specifically refer to §1060.601(f). 

Honda suggested that the final regulation state clearly what parts of §1060.5(b)(3) apply 

to outboard marine engines and avoid implications of requirements associated with completely 

different products (e.g., vessels). Specifically, Honda noted that §1060.5(b)(3) states that 

“manufacturers of outboard engines must meet all the requirements that apply to vessels”. 

Honda believes this is lacking important specificity, overly broad and can lead to 

misinterpretation. Honda commented that the outboard engine manufacturer should be 

responsible for the permeation emission from the fuel lines integral to the engine (under the 

cowl) and permeation emissions from the fuel tank for the very small outboard engines that 

include the tank as part of the engine. All other parts of the fuel system are either part of the boat 

or, as in the case of a portable marine tank, are certified, manufactured and sold by a third party 

and not part of the outboard engine manufacturer production, certification or responsibility. 

Brunswick commented that boat builders already have an overwhelming number of 

certification and labeling requirements for the boat itself and that most companies don't have 

staff for certifying. We need to ensure that we work towards a universal solution regarding these 

matters to avoid confusion. Brunswick noted that NMMA has a current "type accepted" program 

for many safety related components that are installed in boats. A similar approach to the 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

certification requirement would make it a much easier transition for boat manufacturers to 

follow. 

A chorus of boat builders that are NMMA members submitted comments on certification. 

They noted that companies do not have experience or staff in certifying with EPA. They 

commented that there will be a need for EPA to provide training for boat builders on certification 

and penalties. They noted that NMMA has a “type accepted” program, which the industry is 

familiar with, and commented that such a program would make for a smoother transition for the 

industry to certification with EPA? 

Letters: 

Commenter Document # 

Sea Ray 0683 

Honda 705 

RV Industry Association 0647 

Briggs and Stratton 0657 

Brunswick (hearing) 0642 

EMA 0691 

Triton 0656 

Lund Boat Co 0655 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products, Inc. 0652 

Lowe Boats 0660 

Godfrey 0645 

Cigarette Racing 0637 

Regal Marine Industry 0635 

Massachusetts Marine Trade Association 0634 

Regulator Marine Inc 0632 

Chaparral/Robalo Boats 0630 

Ranger Boats 0628 

Larson/Glastron Boats 0626 

Four Winns Boats, Inc 0650 

Skeeter 0706 

Our Response: 

We agree that the rule should balance the respective roles of engine, equipment, and 

component suppliers. We have preserved the proposed framework for assigning certification 

responsibilities, with various adjustments and clarifications as noted below. 

Engine manufacturers must supply equipment manufacturers emission-related installation 

instructions. We expect these instructions to include any necessary requirements, restrictions, or 

other information to ensure that the finished products are compliant with exhaust and evaporative 

emission standards. Equipment manufacturers that do not follow these installation instructions 

are in violation of the prohibitions in §1068.101. 

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We agree that the regulations should allow Small SI manufacturers to use the SHEDbased measurement procedures from California ARB without expiration, as described in Section 

4.7.2. 

We believe we have constructed a certification protocol that minimizes the regulatory 

burden on EPA and industry. By focusing on component certification, we are aiming to place 

certification responsibilities as far upstream in the assembly sequence as possible. This prevents 

multiple equipment manufacturers using a common fuel tank or fuel line from needing to submit 

paperwork to EPA. The regulations allow for equipment manufacturers to assume certification 

responsibilities for components, but this is only where this arrangement is agreeable to both 

component and equipment manufacturers. Control of running losses for nonhandheld engines 

pose a challenge to this approach. Only the manufacturers assembling the complete fuel system 

for engines and equipment can certify with respect to running losses. We are aware that this will 

require the involvement of a large number of companies. However, running loss certification is 

relatively simple, since most companies will use one or at most two approaches. The running 

loss requirement does not involve emission measurement so the application for certification will 

consist of little more than a brief description of the method of control. We believe this approach 

is consistent with the requirements adopted by California ARB. 

We expect to prepare certification documents such that manufacturers can include 

information related to exhaust and evaporative emissions compliance in a single submission. We 

may issue combined or separate certificates for exhaust and evaporative emission controls, but 

we intend to make efforts to simplify data submission as much as possible. We have revised 

§1054.201(a) to specify that separate certifications are required for each engine family; this 

emphasizes that separate certificates apply for families with respect to exhaust emissions without 

limiting our approach for certifying with respect to evaporative emissions. Component 

manufacturers that certify their products are obligated to meet all the requirements associated 

with certification. However, in the case of Small SI equipment, we also require equipment 

manufacturers to certify their equipment. This would allow for an approach to warranty that 

aligns with existing practices. If the equipment manufacturer provides the warranty for 

components, the certifying component manufacturer would have no further obligation to meet 

warranty requirements. In cases where equipment manufacturers don’t certify (most commonly 

with marine vessels), the component manufacturers should make contractual arrangements to 

delegate responsibilities for processing warranty claims. 

We have revised the regulation to move the certification requirements for evaporative 

emissions to part 1060. We have therefore removed the proposed requirement from 

§1060.205(o)(2) to submit evaporative emission data in the application related to compliance 

with exhaust emission standards. Engine and equipment manufacturers that certify with respect 

to evaporative emissions must certify under part 1060. The remaining evaporative-related 

regulations in part 1054 summarize the applicable standards, describe the provisions related to 

emission credits, and present various interim provisions that are specific to Small SI engines and 

equipment. Certifying for compliance with exhaust and evaporative emission standards in 

separate parts does not prevent us from combining these applications for certification, as 

described above. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

We have revised §1054.2 to clarify who is responsible for meeting evaporative 

requirements under part 1054. We have eliminated the reference to component manufacturers, 

since they would be certifying under part 1060 and they have no responsibility for producing or 

installing engines that meet exhaust emission standards. Also, engine manufacturers are 

responsible for meeting evaporative emission requirements only to the extent they install fuelsystem components. However, engine manufacturers that install complete fuel systems are 

considered to be the equipment manufacturer with respect to evaporative emission standards. 

We drafted §1060.5(e)(2) to address three separate scenarios for assigning certification 

responsibilities to different types of manufacturers. EMA’s suggested wording is not 

inconsistent with the proposed language, but it does not allow for a clear presentation of the full 

range of scenarios. We are finalizing these provisions as proposed. 

We have revised §1060.5(e)(1) to refer specifically to §1060.601(f). 

We agree that the proposal included overly broad assignment of responsibility to 

outboard engine manufacturers. We have revised §1060.5(b)(3) to specify that engine 

manufacturers must comply with requirements that apply to vessel manufacturers for those fuelsystem components they install on their engines. This is true for all types of marine engines, so 

we no longer apply this provision only for outboard engine manufacturers. 

We are adopting an approach that minimizes the compliance for boat builders. Boat 

builders that do not build their own fuel tanks will generally be able to buy certified components 

that meet all applicable emission standards (permeation and diurnal). Boat builders must keep 

records to document their compliance and apply a simple label to their vessels. We believe this 

approach is very similar to the type approval described by NMMA. We look forward to working 

with NMMA to ensure that boat builders and component suppliers are informed of the new 

requirements and have access to the tools they need to comply. 

4.7.3 Relationship to California ARB certification (reciprocity, etc.) 

What Commenters Said: 

OPEI noted that as proposed, there are still several conflicts that will prevent 50 state 

products with common certification applications, and common testing, labeling, and warranty 

standards for the same evaporative families. California ARB’s evaporative program allows the 

certifying engine or equipment manufacturers to: 1) Install all the evaporative components; 2) 

Apply an integrated engine exhaust and/or evaporative label; and 3) Issue to consumers a single, 

integrated emission warranty statement – for the complete evaporative system (i.e., tanks and 

fuel lines) – even when a separate component supplier performs the actual tests to demonstrate 

compliance. To further facilitate an efficient certification process, California ARB allows 

manufacturers with the needed flexibility to broadly aggregate families based simply on the use 

of different materials and technologies. 

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OPEI noted that in sharp contrast, under the Phase 3 proposal, EPA would have to issue 

separate and distinct certifications (in all cases) that would require unique labels for each 

individual evaporative component. Unlike California ARB, EPA’s proposal apparently would 

not practically allow a single integrated exhaust and/or evaporative label or combined warranty 

statement from the engine manufacturer or the OEM. OPEI believes that EPA’s proposal creates 

unintended problems and is impractical – given the small spaces for labels on most products. 

EPA’s proposed piecemeal approach would be confusing to consumers, who would have to read 

numerous confusing labels and try to track and apply numerous warranty statements. Moreover 

under EPA’s overly-complicated, piecemeal evaporative program, even manufacturers of 

integrated products could not certify and label a 50-state product – even though it fully meets the 

EPA and California ARB programs. In this regard, EPA’s proposal imposes substantial 

administrative burdens without any benefits. 

OPEI noted that during the interim or transition period (generally before 2011), EPA 

proposed to fully accept California ARB evaporative Executive Orders for evaporative systems 

and components without requiring extensive re-testing and re-certification. OPEI urged EPA to 

permanently accept California ARB Executive Orders as a demonstration of compliance to allow 

manufacturers to avoid wasting substantial resources (re-testing and re-certifying) California 

ARB Tier III-compliant products with no commensurate environmental benefits. For example, 

under the California ARB Tier III program, the complete connected fuel tank and engines on 

walk-behind mowers (and other products certified using the California ARB SHED-performance 

requirements) must be certified under a very stringent SHED-based performance standard that is 

more robust that EPA’s component-based certification program. While OPEI fully supported 

EPA’s assessment that SHED-based testing requirements are not viable or cost-effective for all 

Small SI products, OPEI commented that it does not make any sense to require these California 

ARB-compliant lawnmowers and other products to be re-certified on a component-bycomponent basis. OPEI requested that manufacturers have the option to certify products to 

EPA’s Phase 3 requirements based on previously established performance certification to 

California ARB’s Tier 3 limits. 

EMA commented that EPA should accept engines and equipment that are certified to 

California ARB Tier III standards via compliance with a full diurnal SHED test in addition to 

running loss control requirements. Even though the manufacturer will not have documented 

individual component emission performance for such engines or equipment, EPA should accept 

such engines because they exceed EPA’s required emission reduction expectations. Certain 

products, such as walk-behind lawn mowers certified for California ARB utilizing the SHEDbased performance option will not have individual component emission performance 

documented by the manufacturer; however, such products exceed EPA’s required emission 

reduction expectations. EPA’s acceptance of this testing option will provide a significant 

environmental benefit as well as the much sought after harmonization necessary to enable 

manufacturers to distribute product on a 50-state basis. 

California ARB commented that EPA should specifically consider adopting language 

giving flexibility to accept the California ARB diurnal test results that measure the same or more 

restrictive performance standards as satisfying the EPA requirements for tanks and hose 

assemblies. As part of its evaluation, California ARB is testing the entire tank as one unit, and 

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the hose and primer bulb as an assembly. In this way, the permeation aspect is included in the 

test results. California ARB diurnal test procedures for tanks include permeation as well as 

evaporative emissions from fittings, pickup tubes, and fill caps. Likewise, the hose and primer 

bulb test method includes all fitting and hose connectors. 

OPEI specifically requested that EPA make additional efforts to harmonize all its 

evaporative test methods with the California ARB Tier 3 requirements. Harmonizing soak 

temperatures, tolerances, measurement methods, and reporting requirements will substantially 

reduce regulatory burdens without reducing environmental benefits. OPEI commented that all 

components that have achieved California ARB compliance and received a California ARB 

Executive Order should be approved for use on EPA compliant products without additional 

testing, labeling, or burden on either the engine manufacturer, equipment manufacturer, or fuel 

line manufacturer. 

OPEI also requested that products meeting the California ARB Tier 3 diurnal and running 

loss requirements automatically be deemed compliant with EPA’s Phase 3 running loss 

regulations. 

EMA commented on §1060.105(e)(2) that manufacturers should have the option to 

comply with the design standard requirements by certification with the diurnal requirements 

specified for Small SI engines by California ARB. EMA recommended that an option (v) be 

added that reads as follows: “Have a valid Executive Order from California ARB that includes 

running loss control.” 

EMA commented that a California ARB approved fuel line always should be acceptable, 

not just during the transition period. California ARB compliant fuel lines that have received a 

California ARB Executive Order should be approved for use on EPA compliant products without 

additional testing, labeling, or imposition of any other burden on either the engine manufacturer, 

equipment manufacturer, or fuel line manufacturer. 

In general, California ARB recommended that EPA either modify its proposal to match 

the California program or allow California test results to meet the EPA requirements. 

NMMA and Mercury Marine noted that EPA’s proposal contains an entirely new Part 

1060 which would establish evaporative emissions requirements for all Marine SI engines. They 

also noted that California ARB also is in the process of developing evaporative emissions rules 

for Marine SI engines. Two separate requirements for evaporative emissions create needless 

complexity and impose an additional burden on industry. NMMA and Mercury Marine as well 

as several NMMA member boat builders strongly urged EPA to develop a national evaporative 

emissions rule to simplify the regulatory requirements applicable to marine engine and 

component manufacturers and boat builders. 

Sea Ray also recommended a “national approach” to establish evaporative emissions 

requirements for Marine SI engines. Sea Ray encouraged EPA and California ARB to work as 

partners and develop a national evaporative emissions rule to simplify the regulatory 

requirements and eliminate the regulatory burden of complying with two separate sets of 

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regulatory requirements. Sea Ray commented further that they encourage EPA to look for 

common alignment with the current California ARB rule considerable amount of effort has been 

made to meet those guidelines. They also encourage EPA to work closely with industry on the 

key aspects of this rule. 

Letters: 

Commenter Document # 

Sea Ray 0683 

OPEI 0675 

Mercury 0693 

California ARB 0682 

EMA 0691 

Grady-White Boats 0677 

Triton 0656 

Brunswick Corporation 0695 

Brunswick Commercial and Government Products 0652 

Lowe Boats 0660 

Our Response: 

Our proposed requirements were substantially aligned with the requirements adopted by 

California ARB. We have made several changes in the regulations to eliminate many of the 

remaining areas where there were inconsistent requirements or specifications between the two 

programs. 

Perhaps the broadest area of concern relates to whether equipment manufacturers or 

component manufacturers would need to certify their products. We believe it is the most 

efficient and practical approach to put primary certification responsibilities on component 

manufacturers. They have the primary responsibility to design and produce compliant products. 

They are generally also best positioned to generate emission data and submit applications 

describing how the products meet emission standards. The alternative approach of requiring 

equipment manufacturers to take primary responsibility for certification would greatly increase 

the number of certifying manufacturers and involve a tremendous duplication of effort as dozens 

or perhaps hundreds of equipment manufacturers would certify products from the same 

component manufacturer. 

At the same time, we are aware that there may be legitimate business reasons for 

equipment manufacturers to prefer to take on the certification responsibility instead of 

component manufacturers. Where component manufacturers have a written commitment from 

the equipment manufacturer stating that the equipment manufacturer will certify the product, the 

component manufacturer may delegate all compliance responsibilities to the equipment 

manufacturer. In the case of Small SI equipment, we additionally require equipment 

manufacturers to certify their equipment, largely as a result of the running loss emission 

standards. 

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This sets up a different default than that established by California ARB, but it 

nevertheless allows for a harmonized approach. Manufacturers using any combination of 

component and equipment certification in California can rely on those certifications with EPA, 

as long as the documentation makes it clear who is responsible for certifying each item. 

We are adopting California ARB’s SHED-based procedures on a permanent basis. This 

decision depends substantially on California ARB making a change to their certification fuel to 

include the effects of ethanol on permeation rates. If this does not change, we intend to revisit 

this provision to limit its applicability or to allow it only for testing with EPA’s certification fuel. 

We have revised the regulation in several areas to align with the testing and certification 

provisions adopted by California ARB. One area that remains different is the test fuel. As 

described in Section 4.8, we have determined that it is important to maintain the proposed 

specification including ethanol in the test fuel. California ARB has communicated that they plan 

to revise their specified test fuel, so it is not possible at this point to identify a test fuel that will 

align with California ARB for the long term. The current regulation therefore does not allow for 

components certified using California test fuels to be valid for demonstrating compliance with 

EPA standards. 

We proposed to include a provision allowing manufacturers to use their California ARB 

certification as the basis for meeting EPA’s running loss standards. This provision will remain in 

the final rule. 

We will continue to communicate with California ARB in their effort to set evaporative 

standards for Marine SI applications. 

4.7.4 Production period for component certification 

What Commenters Said: 

EMA and OPEI commented that EPA should not require annual re-certification of fuel 

lines. EPA has sufficient enforcement power to ensure that on-going production remains in 

compliance without an annual certification process. In addition, EPA must provide sufficient 

notice, either directly or through the fuel line manufacturer, to customers if a previously certified 

product will no longer be available as a result of EPA’s determination that the Certificate of 

Conformity is no longer valid. 

EMA commented that once EPA has issued a Certificate of Conformity for a component, 

the Certificate should remain valid until there has been a change in the applicable standard level 

or it has been voided. Component certifications should not require either annual or periodic 

renewal. In the event a component manufacturer certificate is voided as the result of a 

compliance enforcement action, EMA commented that all users of the affected components must 

be provided a minimum of one full model year after notification to identify alternative compliant 

components. 

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Saint Gobain noted that EPA is proposing under §1060.201 that fuel system components 

such as a fuel line hose or tubing must be certified on an annual basis. For components such as 

fuel line hose or tubing as part of the low emission fuel-system equipment, they fail to 

understand the need to recertify this component on an annual basis. Usually when such a 

product is developed, perfected and sold into the industry, the design could have a significant life 

span before it would be modified or discontinued. A typical life span could be 5-10 years. So it 

would seem to be a very redundant and unnecessary requirement to certify this type of 

component for each year of production. In fact such products are never distinguished by model 

years. 

Saint Gobain noted that many of these types products are sold through a network of 

distributors and dealers, thus it could create severe inventory problems. They raised a number of 

questions in their comments. For example would tubing manufactured in 2009 be required to be 

installed on equipment prior to December 31, 2009? Would they be required to brand or label 

the tubing with a model year? If such were the case, then many customers would be forced to 

scrap out any unused tubing or they would want to return it to the manufacturer. This could 

create unnecessary financial hardships. They also asked about the aftermarket application such as 

replacement tubing/hose for marine outboard engines and lawn mowers. Would dealers and 

retailers be required to throw out this unused inventory after December 31st? This would 

basically require an expiration date on such products. 

Saint Gobain suggested that EPA exempt fuel line tubing and hose from the annual 

certification requirement. They observed that annual certification might make sense if the fuel 

line is part of fuel system assemblies built for specific model year equipment. In such cases the 

hose or tubing manufacturer may be subject to annual certification. This would be an example of 

an OEM application where the inventory is carefully controlled. A fuel hose or tubing within a 

family of design should only be required to be certified once for its lifetime of production. 

Letters: 

Commenter Document # 

OPEI 0675 

Saint Gobain 0661 

EMA 0691 

Our Response: 

We agree that fuel components are not generally produced based on annual production 

periods. Thus, neither the proposed regulations nor the regulations being finalized require 

annual certification for components. However, the regulations do not allow component 

certificates to cover indefinite production periods. The longest production period that may be 

covered by a single component certificate is five years. We believe that allowing component 

certificates to cover up to five years of production appropriately balances the need for periodic 

EPA review with the desire to minimize the certification burden. Where components remain 

unchanged for more than five years, the manufacturer can easily obtain a new certificate using 

carryover data. This provisions contrasts with the approach we have taken in emission control 

programs related to exhaust emissions; however, this approach is consistent with Clean Air Act 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

section 213(d), where the Act specifies that EPA may modify the certification protocol where 

that is appropriate. 

On the other hand, since most equipment manufacturers have annual production periods, 

we are requiring that equipment certificates cover only a single model year, in the same manner 

as engine certificates. 

In response to the comment from Saint Gobain, it is important to note that the provisions 

related to production periods only affect what can be produced under a certificate. In general, 

anything that is lawfully produced under a valid certificate can be distributed in U.S. commerce 

later. The exception to this is when new standards take effect. Since these new standards are 

based on the model year of the equipment, should we tighten the standard for fuel lines in the 

future, it would not be permissible for an equipment manufacturer to stockpile fuel lines such 

that the higher-emitting fuel lines are installed after the new standard take effect, even though it 

may have been produced under a valid certificate meeting the earlier less stringent standard. We 

allow for normal inventory practices to eliminate product produced under the less stringent 

standard, much like we have always allowed for equipment manufacturers installing certified 

engines. 

Finally, we disagree strongly with the comments stating that the regulation should allow 

the continued production and sale of components for which we have voided, revoked, or 

suspended the certificate. We have no obligation to make noncompliance with the regulations 

convenient for industry. That would only serve to make such noncompliance more likely. 

Moreover, we have no similar allowance for equipment manufacturers to use noncomplying 

engines. To the extent that engine or equipment manufacturers have concerns about potential 

disruptions to their production, they should address them in their purchase agreements with their 

suppliers. 

See Section 4.7.9 for issues related to replacement components. 

4.7.5 Family criteria 

What Commenters Said: 

Commenter Response 

OPEI and EMA commented that EPA’s proposed 

definition of emission families for fuel tanks to include 

extraneous factors (such as pigment and UV inhibitors) 

would create further inefficiencies and inconsistencies 

with California ARB. This, in turn, would impose 

additional administrative and product-segregation costs 

and burdens without any benefits. OPEI and EMA 

commented that EPA should create a broad evaporative 

tank family definition similar to California ARB’s more 

stringent approach. There is no reason that a 

manufacturer can not evaluate the influence, if any, for 

these additives in the process of determination of a worst 

case selection for testing. By allowing combinations of 

these options within a family the certification process 

The proposal required that manufacturers differentiate 

emission families based on additives that “may affect” 

emissions. We are revising this in the final rule to 

specify additives that “are expected to affect” emissions. 

These additives may have a strong effect on emissions, 

for example, by affecting adhesion of post-processing 

barrier layers, and in many cases it is not apparent which 

recipe would represent the worst-case condition. We 

would expect normal production within a tank model to 

rely on a consistent formula and manufacturers provided 

no basis for needing such a variety. As a result, we 

believe it is necessary and appropriate to require that 

manufacturers separate their products into different 

emission families as described above. 

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Chapter 4: Evaporative Emissions 

burden can be reduced for both the industry and the 

agency. 

Due to a high number of different tanks (over 70 

different versions) in production, OPEI commented that 

EPA should require a test of best and worst surface to 

volume ratio of tanks, to reduce the number of tests. 

The worst emission value would be applicable for 

certification. 

The regulations do not specify additional testing for fuel 

tanks for different values of surface-to-volume ratio. It 

is not clear what change is recommended by the 

comment. 

OPEI commented that EPA should provide information 

on how a manufacturer should establish a family name. 

(See §1060.230) OPEI requested that EPA reference a 

guidance document. 

To the extent that we establish a naming convention for 

evaporative emission families, this would occur outside 

of the rulemaking process. 

EMA noted that the evaporative emission family naming 

convention is not identified in the proposal. EMA 

recommended that the convention be the minimum 

required to identify the family. For engine or equipment 

manufacturers that are also obtaining a Certificate of 

Conformity to the exhaust emission requirements, the 

minimum additional information required to indicate the 

evaporative family should be a two character code 

established by the manufacturer. For other 

manufacturers, the evaporative family name should 

include only a model year designation, manufacturer 

identification code, and a two character code established 

by the manufacturer. 

We will take these suggestions into account if we pursue 

a standardized convention for identifying emission 

families for evaporative emissions. 

EMA and OPEI objected to the requirement for 

manufacturers to submit a new application for a changed 

FEL with respect to fuel tank permeation (see 

§1060.225). They noted that this is not required for 

exhaust emissions. 

We agree that equipment manufacturers should be able 

to change the FEL within an emission family (subject to 

the same restrictions that apply for exhaust FELS), since 

they can easily track their own products to know what 

FEL applies for each tank. This does not apply for tank 

manufacturers that name an FEL and certify their own 

tanks. Requiring them to recertify for a changed FEL 

will help make clear for equipment manufacturers which 

FEL applies for each tank. 

EMA commented on §1060.205 that Small SI engine 

and equipment manufactures that are required to certify 

to the running loss requirements specified in 

§1060.601(c) must have the ability to include in their 

certification submission component Certificate of 

Conformity information in place of the specific product 

selection and testing requirements proposed. 

We expect to arrange certification templates to allow for 

engine manufacturers to include certification 

information showing that they meet running loss 

standards. However, as described in §1027.115, we 

would apply a separate certification fee for evaporative 

compliance. This fee is considerably lower than the fee 

for exhaust emission compliance. Also, a single fee 

would apply for all evaporative compliance in the same 

emission family as described in §1060.230. This allows 

manufacturers to group products from the same engine 

family for exhaust emissions into a bigger combined 

family for evaporative emissions. 

EMA commented on §1060.230(c) that it is 

inappropriate to include fuel cap design as a criterion in 

establishing emission families for fuel tanks. 

We specify that fuel cap design is relevant for defining 

emission families only with respect to diurnal emission 

controls (the proposal also include reference to diffusion 

emissions, but that is not part of the final rule). Fuel cap 

design is therefore of interest for Small SI equipment to 

the extent that they use California’s SHED-certified 

approach and the fuel cap varies in ways that are 

relevant to diurnal emission control. We believe this is a 

reasonable approach. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

MIC commented that the language of §1060.230(g) says, We agree with this suggestion and have moved the 

“Select test components that are most likely to exceed testing-related text to §1060.235 

the applicable emission standards. For example, select a 

fuel tank with the smallest average wall thickness (or 

barrier thickness, as appropriate) of those fuel tanks you 

include in the same family.” This text appears to be 

misplaced because 1060.230 addresses how to divide 

product into engine families, not how to select 

components for testing. 

Letters: 

Commenter Document # 

MIC 0701 

OPEI 0675 

EMA 0691 

4.7.6 Design-based certification– fuel tank permeation 

What Commenters Said: 

NMMA expressed strong support for the inclusion of provisions allowing design-based 

certification for manufacturers of tanks and components. NMMA stated that it will significantly 

reduce the testing burden placed on manufacturers by providing the option to certify products 

using a design-based approach. In addition, NMMA commented that such measures are 

necessary in order to facilitate compliance with the rule across a diverse group of affected 

businesses. Inca also commented that the design-based certification process should be included 

in the final rule.

 Fluoro-Seal International proposed that undeveloped technology be allowed for future 

consideration as a compliance option by including an “innovative product” review and 

qualification procedure in this regulation. Fluoro-Seal commented that allowing for the 

development of innovative products will enable continuous improvement of materials and 

systems for lowering emissions from fuel handling systems and recommended the following 

approach: 

(a) EPA would require a manufacturer to demonstrate by clear and convincing evidence that, 

due to the product’s design, delivery system, or other factors, the use of the product will 

result in lower emissions below the highest level allowed by rule. 

(b) A manufacturer (applicant) would apply in writing to EPA for an innovative product 

exemption claimed under a subsection to be written. The application would include the 

supporting documentation that quantifies emissions from the innovative product, including 

the actual physical test methods used to generate the data. In addition, the applicant would 

provide any information necessary to enable the EPA to establish enforceable conditions for 

granting the exemption. 

(c) Within 30 days of receipt of the exemption application EPA would determine whether an 

application is complete as required by rule. 

(d) Within 90 days after an application has been deemed complete, EPA would determine 

whether, under what conditions, and to what extent, an exemption from the requirements of 

said rule will be permitted. An applicant would be allowed to submit additional supporting 

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documentation before a decision has been reached. The EPA would notify the applicant of 

the decision in writing and specify such terms and conditions that are necessary to ensure that 

emissions from use of the product will meet the emissions reductions specified in the rule, 

and that such emissions reductions can be enforced. 

(e) In granting an innovative product an exemption, EPA would specify the test methods for 

determining conformance to the conditions established. The test methods may include criteria 

for reproducibility, accuracy, and laboratory sampling procedures. 

Letters: 

Commenter Document # 

NMMA 0688 

Fluoro-Seal 0646 

Inca Molded Products 0700 

Our Response: 

We are finalizing design-based certification provisions for meeting the fuel tank 

permeation standards. We agree with commenters that design-based certification would reduce 

the testing burden for manufacturers. However, we believe that this approach should only be 

used when the technology is well understood and the design constraints can be clearly specified. 

As proposed, we are allowing design-based certification to the fuel tank permeation standards for 

metal fuel tanks and for co-extruded fuel tanks with a continuous ethylene vinyl alcohol (EVOH) 

barrier layer. Metal does not permeate, and the EVOH-barrier tank design specified in the 

regulations is a well established technology that has long been proven in automotive and other 

applications as having a permeation rate well below the standards finalized in this rule. 

Fluoro-Seal describes an approach in which manufacturers would provide “clear and 

convincing evidence” that a product will meet the tank permeation standard including test 

procedures specified by EPA. This approach is very similar to the direct certification procedures 

for these fuel tanks. To certify a fuel tank family to our standards, manufacturers would perform 

emission testing on the fuel tank design in the family expected to have the highest permeation 

rate. The test data are then used to certify a whole family of similar products. In addition, the 

manufacturer may carry this data over from year to year. 

We believe that it is important that the fuel tank manufacturer certify to the standards, 

rather than a material supplier or a post-process treatment facility. The final permeation 

performance of the fuel tank depends heavily on the design of the fuel tank and the actual 

manufacturing process. Specifically for surface treatments, data in the RIA suggests that the 

performance of these barrier technologies is a function of a wide range of variables, including the 

material used for the fuel tank, additives to this material, and processing temperatures and 

pressures that are typically held confidential. For these reasons, we believe that any new 

treatment process and tank material combination should be tested to ensure proper performance. 

We may establish additional design-based certification options where we find that new 

test data demonstrate that the use of other technology designs will ensure compliance with the 

applicable emission standards. These designs will need to produce emission levels comfortably 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

below the new emission standards when variability in the emission control performance is 

considered. In addition, all aspects of these designs would need to be publicly available and 

quantifiable. For instance, we would not create an design-based certification for a material or 

process without full public disclosure of all of the characteristics of that material or process 

relevant to its emission barrier performance. We would also not include products whose 

emission performance is highly variable due to tolerances in materials or manufacturing 

processes. 

4.7.7 Design-based certification– diurnal 

What Commenters Said: 

NMMA expressed strong support for the inclusion of provisions allowing design-based 

certification for manufacturers of tanks and components. NMMA stated that it will significantly 

reduce the testing burden placed on manufacturers by providing the option to certify products 

using a design-based approach. In addition, NMMA commented that such measures are 

necessary in order to facilitate compliance with the rule across a diverse group of affected 

businesses. 

Delphi commented in favor of the proposed provisions for design-based certification, 

including the canister design requirements and the minimum carbon butane working capacity of 

9 g/dL. All carbon grades utilized for automotive and other canisters produced by Delphi have 

butane working capacities greater than or equal to 9 g/dL. Delphi expressed support for the 

canister sizing requirements of a minimum of 0.04 liters per gallon of fuel tank capacity for 

trailerable boats and 0.016 liters per gallon for non-trailerable boats. Delphi stated that these 

carbon volumes should provide good efficiency while allowing for canisters that can be 

packaged in boats. Delphi also expressed support for the minimum length-to-diameter ratio of 

3.5, and the use of a volume compensator to reduce carbon abrasion. 

MeadWestvaco Corporation stated that it supports the proposed design-based 

certification provisions for diurnal emissions, but expressed concern that the proposed carbon 

requirements do not include a specification for mean particle diameter. For any given flow rate 

of air or vapor through activated carbon, the pressure drop across the carbon bed increases with 

decreasing particle size. MeadWestvaco stated that without a requirement for carbon particle 

size, a very finely sized activated carbon could be used within the canister that meets the above 

requirements but has characteristics of very high flow restriction, making the carbon canister 

unusable. MeadWestvaco Corporation suggested that a minimum Mean Particle Diameter of 3.1 

mm, based on ASTM procedure D2862, be included in the design-based certification carbon 

requirements outlined in § 1060.240(d) to ensure low pressure drop while continuing to maintain 

carbon functionality. 

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Chapter 4: Evaporative Emissions 

Letters: 

Commenter Document # 

NMMA 0688 

MeadWestvaco Corporation 0723 

MeadWestvaco Corporation 0724 

Delphi 0638 

Our Response: 

We are finalizing design-based certification provisions for meeting the diurnal emission 

standards. We agree with commenters that design-based certification would reduce the testing 

burden for manufacturers. The final design specification for carbon canisters include 

MeadWestvaco’s recommendation that the carbon granules must have a minimum mean 

diameter of 3.1 mm based on the procedures in ASTM D2862. We believe that this additional 

specification is necessary to prevent canister designs with high flow restrictions. 

4.7.8 Warranty 

What Commenters Said: 

California ARB noted that EPA proposed a two-year period for emission-related 

warranties with respect to evaporative emission controls. This period is not long enough to 

ensure that quality evaporative control devices will be used and will stay consistent with engine 

warranty periods. ARB recommended a five year warranty period, consistent with engine 

warranty. 

EMA commented that it is not practical for certifying component suppliers to provide an 

emission-related warranty. The emission warranty requirement should be placed on the engine 

or equipment manufacturer that assembles the complete evaporative control system with 

appropriate contractual agreements between the engine/equipment manufacturer and their 

component suppliers. The general requirements should be revised such that the engine or 

equipment manufacturer that provides the commercial warranty for an engine or equipment must 

provide the emission-related warranty. The component supplier will be accountable to the 

engine/equipment manufacturer by way of the contractual relationship between the parties. 

Accordingly, EMA commented that §1060.120(a) should be revised to read as follows: “The 

engine or equipment manufacturer that provides the commercial warranty for an engine or 

equipment must warrant to the ultimate purchaser and each subsequent purchaser that the new 

nonroad equipment conforms with the requirement of this part at the time of sale and is free from 

defects in materials and workmanship that may keep it from meeting these requirements.” 

Letters: 

Commenter Document # 

California ARB 0682 

EMA 0691 

4-90
Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

Our Response: 

California ARB’s comment confuses useful life and warranty periods. Current 

regulations for Small SI in part 90 and Marine SI engines in part 91generally specify warranty 

periods of two years. EPA’s general approach in more recent rulemakings is to set warranty 

periods to be half of the applicable useful life. This approach for evaporative requirements takes 

a similar approach. We expect this to have very little impact on the way manufacturers design or 

produce their products. Evaporative emission controls are generally not susceptible to defects 

that would cause an owner to bring the product in for repairs. 

In the final rule, we require Small SI equipment manufacturers to certify with respect to 

evaporative emissions. For Marine SI vessel manufacturers, certification is optional. For both 

cases, we specify that component manufacturers may meet their warranty obligations if a 

certifying equipment or vessel manufacturer meets warranty requirements. If a vessel 

manufacturer does not certify, the component manufacturers would be expected to make an 

agreement with the vessel manufacturer to process warranty claims on their behalf, or otherwise 

to combine efforts to fulfill the warranty obligation. 

4.7.9 Replacement components 

What Commenters Said: 

NMMA noted that EPA proposed in §1060.601(b)(3) that in cases where a fuel tank is 

replaced, the replacement tank should have the same or lower FEL as the original fuel tank. If 

such a tank is not available, EPA proposed to allow equipment owners to request an exemption 

from the anti-tampering provisions if there is no low-FEL tank available. NMMA commented 

that this situation is very likely to occur in the future as molded tanks eventually wear out and the 

older molds are no longer available. NMMA agreed that such situations should be exempt from 

the tampering provisions. However, customers in these situations should be able to put whatever 

tank fits in the vessel without having to request an exemption. NMMA commented that an 

exemption process is administratively burdensome and impractical and the requirement for a 

formal request should be removed from the final rule. 

Arctic Cat requested that specific language be added that would allow more flexibility in 

supplying replacement fuel tanks. Arctic Cat noted that since the vehicle emission control 

information (VECI) label specifically states the permeation family name, they have been told by 

certification staff that replacement tanks that do not match the information on the VECI label 

would not be allowed. To recreate the precise tank that was made in the past has significant cost 

impact and adds little value for anyone. In fact, the high cost of these replacement tanks could 

motivate the customer to find an alternative that may result in much higher permeation. Arctic 

Cat does not feel that EPA's original intent was to disallow flexibility for providing replacement 

tanks by adding requirements to include the permeation family name on the VECI label. They 

requested the addition of a paragraph that allows any fuel tank from a permeation family that has 

already been certified under the same or other engine family to be used as a replacement tank as 

long as it meets the same FEL or standard as the tank being replaced. 

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Chapter 4: Evaporative Emissions 

OPEI commented that they agreed with the provision to allow equipment owners to ask 

for an exemption from the tampering prohibition if there is no low-FEL tank available. The 

replacement tank would still need to meet applicable standards, but would not need to meet the 

more stringent emission levels reflected by the old tank’s FEL. OPEI believes there should be 

special provisions to allow historical fuel tanks (fuel tanks used on products produced before low 

permeation regulations were enforced) to be supplied as replacement parts for all time for those 

products. 

Letters: 

Commenter Document # 

NMMA 0688 

Arctic Cat 0709 

OPEI 0675 

Our Response: 

We have revised the regulations to clarify that new fuel tanks need not be certified to the 

permeation standards if they will be installed as replacement tanks where the original tank was 

not subject to emission standards. This allows for continued production of replacement fuel 

tanks that are identical to the original tanks, or otherwise in something other than a lowpermeation configuration. 

In cases where replacement tanks will be installed in equipment in which the original 

tanks were certified with an FEL below the applicable standards, we agree with the commenters 

that it would be inappropriate to require manufacturers to match that same level of emission 

control with the replacement tank, or to require owners to go through a process to get EPA 

approval for a waiver from this requirement. As long as these replacement tanks are certified, 

we will consider them to be compliant with EPA requirements. This avoids imposing the burden 

of tracking product and prevents a situation where manufacturers are unable to supply lowpermeation fuel tanks of a different configuration than the original fuel tank. 

Equipment manufacturers may identify multiple valid fuel tank models (or emission 

families) on their labels or in their applications for certification. If they do this it will be easier to 

establish that equipment with a replacement fuel tank that differs from the original configuration 

is still in a certified configuration. This would also accommodate a production scenario in which 

the equipment manufacturer includes different kinds of fuel tanks for a given equipment model 

(for example, by sourcing fuel tanks from different component manufacturers). 

4.7.10 Other certification issues 

Summary of Comment Response 

EMA commented on §1060.225(c) that the requirement 

to supply additional test data within 30 days of EPA’s 

request is not appropriate. The requirement should 

specify that manufacturers must supply data within 30 

days after completion of the testing associated with 

EPA’s request. 

We agree that it may take more than 30 days to respond 

to certain requests. For example, any testing that 

requires preconditioning components would take several 

weeks to be able to run a valid test. As a result, we are 

modifying the regulation to specify that the 

manufacturer must either give us the information within 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

30 days or give us a plan for providing the information 

in a timely manner. 

EMA commented on §1060.235(f) that the method used 

to determine the official test results must be identified 

for cases when more than one unit is tested. EMA 

suggested that the average of all test results should be 

considered the official test results. 

Section 1060.801 defines the “official emission result” 

as the measured emission level from a certification test 

on a given tested component. The “certified emission 

level” is defined as the highest official emission result 

from a family. This approach is consistent with the 

terminology and practice for exhaust emission testing for 

all nonroad engines. 

EMA commented that a demonstration of durability as 

part of the determination of compliance for a given fuel 

system technology is appropriate. However, due to the 

long term stabilization requirement to generate test result 

for permeation testing it is not practical to utilize 

deterioration factors as typically applied to exhaust 

emissions. 

We adopted an approach that relied on deterioration 

factors for recreational vehicles, but have since 

concluded that deterioration factors are not a sensible 

approach for testing and certifying fuel tanks for 

permeation emissions. We did not include this approach 

in the proposed rule or this final rule. We expect to 

revise the rule for recreational vehicles to align with this 

new approach. 

EMA noted that §90.127(c)(2) requires the engine 

manufacturer to provide appropriate instructions to 

equipment manufacturers adding a fuel line so that they 

may meet the requirements set forth in §90.128, if they 

add fuel line. However, EPA does not indicate what the 

approval process is for such instructions. EMA 

commented that this section should be revised to read as 

follows: “It is not a violation to introduce your engines 

into U.S. commerce if other companies add fuel lines 

when installing your engines pursuant to §90.128. 

[Emphasis added.] 

We believe it is not necessary to amend the regulation as 

recommended by EMA. The text simply describes how 

responsibilities for including compliant fuel lines fall on 

engine and equipment manufacturers. The installation 

instructions should make clear that any additional fuel 

line coming from the equipment manufacturer is their 

responsibility. 

EMA noted that the manner in which installation 

instructions are provided to engine installers will vary 

significantly depending on the business relationship 

between the engine manufacturer and equipment 

manufacturer. EMA commented on §90.128(c) that 

instead of requiring the manufacturer to provide an 

explanation of how the manufacturer will ensure that 

installers are informed of the installation instructions, 

the manufacturer should be required to retain records 

demonstrating how the notification was provided. 

EMA is not objecting to the requirement to notify 

installers regarding the installation instructions. In 

effect, their request is to avoid committing to a specific 

plan ahead of time and instead document afterward how 

this occurred. We believe it is quite appropriate to 

identify a plan for communicating installation 

instructions to installers. This might involve a variety of 

methods and manufacturers would not need to identify 

the method used for each company. It would be enough 

to identify the nature of the communications that are 

intended to ensure proper installation. 

OPEI noted that §1060.520 does not define the quantity 

of fuel tanks required for testing and certification. The 

quantity of tanks tested during cert should be discussed 

with industry. 

We have indeed had these discussions and concluded 

that testing a single tank is appropriate, except that three 

tests are required for certifying based on a Family 

Emission Limit. There was some interest in testing 

more than one tank for other families, but we believe 

this is best left to the manufacturer’s discretion. 

However, we may require manufacturers to test 

additional fuel tanks if we believe that is necessary to 

ensure proper certification. 

Letters: 

Commenter Document # 

EMA 0691 

OPEI 0675 

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Chapter 4: Evaporative Emissions 

4.8 Test procedures 

4.8.1 Fuel line permeation– preconditioning 

What Commenters Said: 

NMMA and Mercury Marine expressed support for the proposed procedures for fuel line 

permeation testing. NMMA noted that it would defer to its members’ comments on whether a 

longer soak period would be necessary for fuel lines. 

In its comments, OPEI noted that the proposed fuel line preconditioning period is for 4 to 

8 weeks and 23°C ± 5°C. OPEI expressed concern that this may lead to too much variation in 

test procedures and results. Therefore, OPEI recommended that a single preconditioning period 

be set, such as 8 weeks, so that any in-use or compliance checks EPA conducted would agree 

with manufacturer testing. In addition, OPEI recommended that the temperature tolerance be 

changed from ± 5°C to ± 2.5°C. 

California ARB commented that the proposed preconditioning soak time for fuel lines 

should be at the higher end of the proposed soak times (8 weeks or more). The commenter 

noted that the Society of Automotive Engineers (SAE) J1737 recommends 1000 hours 

(approximately 6 weeks) to sufficiently achieve steady state for 60°C. California ARB stated 

that if the temperature is lower than 60°C, the overall soak time should be lengthened. 

Correspondingly, California ARB recommended that, because the proposed preconditioning soak 

temperature is 23°C, the soak time should be substantially longer to ensure the permeation rate 

has reached steady-state. California ARB’s concern was that a permeation rate calculated before 

it reaches steady-state may represent a lower rate than the actual permeation rate of the fuel line. 

California ARB commented that a higher test temperature of 40°C would shorten the 

preconditioning soak time. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

California ARB 0682 

OPEI 0675 

Our Response: 

The purpose of the proposed preconditioning soak period was to ensure that the fuel line 

had reached a stable permeation rate prior to the permeation test. We believed that a fuel line 

with a permeation rate at the proposed standard of 15 g/m2

/day would require approximately 4 

weeks to reach a steady permeation rate. For more fuel resistant products, we believed that a 

longer fuel soak period may be necessary to make an accurate measurement of permeation. For 

this reason, we proposed a soak period of 4 to 8 weeks to allow for longer soak periods, if 

necessary. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

According to SAE recommended practice,5

 a fuel line permeating at 10-20 g/m2/day at 

60°C fuel should have a preconditioning soak period of approximately 6 weeks at 60°C. Based 

on the relationship between permeation and temperature, it is reasonable to conclude that a 6 

week preconditioning soak period at 23°C is appropriate for testing a fuel line with a permeation 

rate of 10-20 g/m2

-day at 23°C. For fuel lines with a lower permeation rate, a longer soak time is 

necessary to ensure a stable permeation rate. Considering that fuel lines will likely be certified 

with a compliance margin below the standard, we believe it is reasonable to conclude that an 8 

week preconditioning soak period is appropriate for most fuel lines subject to this standard. 

The intent of the proposed wide temperature range for the preconditioning soak was to 

simplify the preconditioning soak by requiring less sophisticated temperature control. We 

believe that this tolerance can be allowed without significantly affecting the results of the 

permeation test. 

Manufacturers commented that the preconditioning soak period must be rigid to ensure 

that in-use compliance testing would match manufacturer testing. In most cases, fuel lines 

sampled for in-use testing would be exposed to fuel for more than 8 weeks. For this reason, we 

believe that it is important that certification testing include a minimum soak period that ensures a 

stable permeation rate. In addition to the 8 week preconditioning soak period, we are finalizing a 

requirement that the fuel line should be preconditioned for a longer period, based on good 

engineering judgment, if necessary to achieve a stable permeation rate. 

For fuel tank testing, the preconditioning soak period may be shortened if performed at 

elevated temperature. Consistent with this provision, we are finalizing a provision that the fuel 

line preconditioning soak period be 4 weeks if performed at 43°C ± 5°C. 

4.8.2 Fuel line permeation– test fuel 

What Commenters Said: 

California ARB commented that the proposed test fuel, CE10, should continue to be the 

test fuel of choice because it is a known blend and is readily available. California ARB stated 

that allowing Indolene with 10 percent ethanol (IE10) should not be adopted because IE10 has a 

lower permeation rate than CE10, and its use would allow less efficient control technology to 

pass the fuel permeation test procedure. NMMA and Mercury Marine also expressed support of 

the proposed test fuel for fuel line permeation. 

EMA commented that EPA incorporate the California ARB Tier 3 methods as specified 

in CCR 2754(a)(1)(C) for measurement of fuel line permeation. EMA commented that the 

alternative should be allowed of using data generated using SAE J30 test method with 

appropriate adjustments to test temperature and test fuel per Phase 3 requirements. 

5 Nonmetallic Fuel System Tubing with One or More Layers,” SAE Recommended Practice J2260, November 

1996. 

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Chapter 4: Evaporative Emissions 

OPEI commented that the water limit in the test fuel should be limited to 500 ppm to 

avoid interaction with nylon materials. OPEI stated that nylon materials have an affinity for 

water, so this can affect the accuracy of permeation tests. In this regard, OPEI argued that 

harmonization with California ARB test fuel (E0) would be recommended. OPEI also 

recommended that manufacturers should be provided the flexibility to conduct permeation 

emission testing with a variety of fuels to minimize the duplication of testing and also overall 

testing burden. No standard level adjustment or other means should be included to account for 

the small differences in permeation rate for relatively similar fuels. OPEI did recognize that 

testing without ethanol does produce a significantly different permeation rate for some fuel line 

technologies and recommended that E0 should not be allowed without development of an 

appropriate adjustment factor to preserve a level competitive playing field. 

In later discussions, OPEI commented that their support of a limit of 175 g/m2

/day for 

cold weather fuel lines is predicated on using IE10 as a test fuel.6

 They stated that the fuel line 

test data supplied to EPA by OPEI was based on this test fuel and supplied further test data using 

fuel CE10 which showed higher permeation results. As a result, OPEI recommended a test fuel 

of IE10 for cold weather fuel lines. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

California ARB 0682 

OPEI 0675 

EMA 0691 

Our Response: 

We are finalizing a test fuel of CE10 for fuel line permeation testing. Fuel CE10 is 

widely used by material manufacturers and hose manufacturers for determining fuel resistance 

from fuel system materials, particularly those used in fuel lines. In addition, the technological 

feasibility of the fuel line standards was largely based on testing using fuel CE10. Based on data 

presented in the RIA, permeation testing based on IE10 results in lower measured emissions for 

most fuel system materials. 

The California ARB Tier 3 methods as specified in CCR 2754(a)(1)(C) for measurement 

of fuel line permeation include a number of test fuels that may be used. Two of these test fuels 

are fuel CE10 and California certification gasoline which does not include ethanol. We are not 

incorporating the California ARB method because we believe that the test fuel for fuel lines 

should include ethanol. Gasoline containing ethanol is widely used in-use and ethanol can have 

a large effect on the permeation rates of fuel lines. In the case where a manufacturer wishes to 

use a single test fuel for certification to the California ARB and EPA standards, CE10 may be 

used in both instances. 

6

 “HHPC Evaluation of EPA Proposed Phase 3 Rule for Fuel Line Permeation,” Outdoor Power Equipment Institute, 

Presentation to EPA, February 5, 2008 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

We believe it would not be appropriate to develop an adjustment factor for the use of fuel 

with and without ethanol for all fuel lines. As shown in the RIA, the effect of ethanol on 

permeation varies greatly for different materials used in fuel lines. 

We are finalizing specifications for fuel ethanol blended into test gasoline based on 

standard industry practice. Specifically, we are incorporating by reference ASTM D4806-077 

which specifies a maximum water content, in the ethanol, of 1 percent by volume. When this 

ethanol is blended into gasoline at 10 percent, this would result in a maximum water 

concentration of about 1,000 ppm. Because this is a maximum, manufacturers testing 

hygroscopic materials would be able to test using fuels with lower water content. 

One exception is for fuel lines on cold-weather handheld products. In this case, the 

standard is based on a test fuel of IE10, which is EPA certification gasoline blended with 10 

percent ethanol by volume. Note that the standard is based on test data in which IE10 was used. 

If we had used CE10 as a test fuel for these products, then the numerical level of the standard 

would have needed to be raised significantly to achieve equivalent emission reductions. 

4.8.3 Fuel line permeation– measurement method 

What Commenters Said: 

NMMA and Mercury Marine expressed support of basing the fuel line permeation test 

procedure on a weight-loss method similar to what is specified in the recommended practices in 

SAE J30 and J1527, with adjustments (discussed above) to the preconditioning soak and test 

fuel. 

OPEI commented that handheld fuel lines are typically shorter than the length required 

for testing under SAE J30. OPEI stated that, if EPA will perform in-use testing of handheld fuel 

lines, a different test procedure is required which will need correlation to SAE J30. 

California ARB commented that EPA should consider increasing the test temperatures 

for fuel line permeation testing to 40°C because, as permeation rates lower, accurate 

measurements become increasingly difficult. Also, a higher test temperature would shorten the 

preconditioning soak time; newer technology increases a component’s resistance to permeation, 

thus taking longer to reach steady-state conditions. 

California ARB also commented that the permeation test procedure and standards for 

hoses and primer bulbs should require only the entire hose assembly be tested as a unit and not 

allow for individual components. California ARB test data and field surveys show that many 

consumers assemble the individual component parts incorrectly. Therefore, California ARB 

supports testing the hose and primer bulb as an assembly, thus reducing the excess emissions 

caused by improper assembly. 

7 ASTM International, “Standard Specification for Denatured Fuel Ethanol for Blending with Gasoline for Use as 

Automotive Spark-Ignition Engine Fuel, ASTM D4806-07, 2007. 

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Chapter 4: Evaporative Emissions 

EMA commented that EPA should work with California ARB to ensure that evaporative 

emission test procedures are aligned to the greatest extent possible. Therefore, EMA 

recommended that the final rule include or incorporate by reference California ARB Tier 3 

methods as specified in CCR 2754(a)(1)(C). Alternatively EMA commented that we should 

allow certification using data generated using SAE J30 test method with appropriate adjustments 

to test temperature and test fuel per Phase 3 requirements. EMA argued that methods based on 

the SAE J30 test method has been the most widely used method for certifying to California ARB 

Tier 3 fuel hose permeation requirements. 

Harold Haskew & Associates (HH&A) commented that permeation mass measurements 

using ethanol containing fuels will produce different results if determined by the weight loss 

method and compared to the current SHED procedure. The issue here is that if one tests for 

permeation using a SHED, and uses the Federal calculations for mass emissions found in 40 CFR 

§86.143-96, the ethanol fraction of the permeate is reported as “equivalent gasoline.” The 

equivalent gasoline deletes the oxygen mass and lowers the hydrogen/carbon fraction from 3 to 

2.3, both resulting in a lower than real mass calculation. As a result, if the SHED mass emissions 

measurement is compared to a gravimetric (weight loss) measurement, the SHED value will 

under-report the true value. 

HH&A recommended a revision to the SHED mass calculation where the ethanol 

contribution to permeation would be measured separately. A Flame Ionization Detector would 

be used to measures total hydrocarbons. This reading would then be corrected by subtracting the 

concentration of ethanol measured by the gas chromatograph (GC). This corrected reading 

would be used to compute non-ethanol hydrocarbon mass emissions. To this value you would 

add the ethanol concentration converted to mass using the true mass of the ethanol molecule. 

Letters: 

Commenter Document # 

NMMA 0688 

Mercury 0693 

California ARB 0682 

HH&A 0640 

EMA 0691 

OPEI 0675 

Our Response: 

As proposed, the fuel line test procedures will reference the weight loss test procedure in 

SAE J30 or J1527 with modifications to the fuel line preconditioning procedure and test fuel. 

Both test procedures are similar in that a reservoir and weight loss method is used. Both SAE 

J30 and J1527 specify minimum fuel line lengths. Especially for in-use testing, it may not be 

possible to identify fuel line samples that meet these minimum length requirements. Therefore, 

we have included a provision to allow fuel line permeation testing to be performed with shorter 

sample sections. Good engineering judgment would be required in testing shorter fuel line 

samples. For instance, the reservoir size may need to be scaled down for the smaller fuel line 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

volumes. Also, additional steps may be necessary to ensure that air is not trapped in narrow 

diameter fuel lines beyond tapping the hose (as recommended in SAE J30). 

We are retaining the proposed nominal test temperature of 23°C for fuel line testing. 

This is the same temperature recommended in SAE J30 for weight loss testing and is consistent 

with our test procedures for recreational vehicles. However, because testing at 40°C would 

result in an increased permeation rate, we would accept data at this temperature as well. Many 

of the fuel lines certified to the California ARB standards were tested at 40°C on fuel CE10 and 

were below our permeation standards. As discussed above, we would accept a shorter 

preconditioning soak at a nominal temperature of 40°C. 

We are finalizing fuel line permeation standards that will apply to primer bulbs and fuel 

hose independently. In many cases, the fuel hose and primer bulbs may be produced by different 

manufacturers. This approach would allow individual component manufacturers to certify to our 

standards. As an alternative, we will allow manufacturers who supply a whole primer bulb and 

fuel line assembly to test the assembly, as a whole, for certification to the fuel line permeation 

standards. 

California ARB’s regulations, in CCR 2754(a)(1)(C), reference SAE J17378

 as the 

method for measuring permeation from fuel lines. These recommended procedures use a 

recirculation technique whereby nitrogen is flowed over the test sample to carry the permeate to 

adsorption canisters. Permeation is determined based on the weight change of the canister. This 

method was intended to provide a greater level of sensitivity than the weight loss method 

specified in SAE J30 and J1527 so that lower rates of permeation could be measured. As an 

alternative, we will accept permeation data collected using the methodology in SAE J1737. If 

this alternative is used, the same test fuel, test temperature, and preconditioning period must be 

used as for the primary (weight-loss) test method. 

In addition, manufacturers may request the use of other procedures provided that these 

procedures are equivalent or more accurate than the primary test procedures or if it can be 

demonstrated that the use of the alternate test procedure would not affect the ability to 

demonstrate compliance. In the case of SHED testing, the manufacturer would need to 

demonstrate that it is correctly accounting for the ethanol content in the fuel. One approach may 

be to use a procedure similar to that described above in the HH&A comments. 

4.8.4 Fuel tank permeation– preconditioning 

What Commenters Said: 

NMMA commented that the shortened tank permeation test procedures for recreational 

vehicles specified in a guidance letter from EPA be allowed for marine fuel tanks.9 This 

8 SAE Recommended Practice J1737, “Test Procedure to Determine the Hydrocarbon Losses from Fuel Tubes, 

Hoses, Fittings, and Fuel Line Assemblies by Recirculation,”1997, (Docket EPA-HQ-OAR-2004-0008-0178). 

9 Dear Manufacturer Letter from Merrylin Zaw-Mon, Re: Alternative Test Procedures for Measuring Fuel Tank 

Permeation from Highway Motorcycles, ATVs, Off-highway Motorcycles and Snowmobiles, Document No. CCD05-14 (MC/ATV/OFMC/ICI/Snowmobiles), Aug. 17, 2005. 

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Chapter 4: Evaporative Emissions 

guidance included a shortened preconditioning soak period of 10 weeks if performed at an 

elevated temperature of 43°C ± 5°C. 

EMA commented that EPA should work with California ARB to ensure that evaporative 

emission test procedures are aligned to the greatest extent possible. EMA recommended that the 

final rule include or incorporate by reference the California ARB’s TP-901 procedures including 

an alternative permeation preconditioning soak temperature of 40°C ± 5°C. OPEI also requested 

that EPA accept the California ARB preconditioning procedure as an alternate test method. 

EMA claimed that testing has shown that most materials meeting the proposed permeation limits 

attain a steady-state permeation rate after soaking for less than 10 weeks. Therefore, EMA 

recommended a process for alternative procedure approval in which manufacturers would be 

allowed to obtain agency approval to utilize shorter stabilization periods if they can demonstrate 

that permeation rates have stabilized in this time period. 

EMA also commented that the requirement that the tanks be sealed during their pre-test 

conditioning soak is not viable. EMA argued that there is no data available to support that 

sealing the tank during the conditioning soak is critical to accurate characterization of the 

material’s permeability; therefore, the requirement for sealing tanks during the preconditioning 

soak should be removed. 

OPEI expressed support for the option of allowing the durability testing to be considered 

as part of the preconditioning soak period. 

Letters: 

Commenter Document # 

NMMA 0688 

OPEI 0675 

EMA 0691 

Our Response: 

For fuel tank testing, the preconditioning soak period may be shortened to 10 weeks if 

performed at an elevated temperature of 43°C ± 5°C. This is consistent with current practices for 

recreational vehicles. In addition, the preconditioning soak temperature overlaps significantly 

with the preconditioning soak temperature in TP-901. Therefore, a single tank could be 

preconditioned, simultaneously, under both the EPA and California ARB procedures by simply 

holding the temperature to 41.5°C ± 3.5°C. The intent of the wide temperature range for the 

preconditioning soak is to simplify the preconditioning soak by requiring less sophisticated 

temperature control. However, as noted above in the manufacturer comments on the fuel line 

preconditioning soak temperature, much tighter temperature tolerances can be maintained. 

EMA did not present data to support its claim that materials reach a steady-state 

permeation rate in less than 10 weeks. We believe that the final preconditioning soak periods are 

appropriate as a minimum for fuel tanks meeting the permeation standards. These soak periods 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

are consistent with recommended practice for permeation testing of polymer-based fuel tubing10 

and provide some assurance that the fuel tanks have reached a stable permeation rate. In the case 

of a very low permeation tank, we would expect the manufacturer to use a longer soak period, as 

appropriate. 

EMA did not provide any information on why they did not consider sealing tanks during 

the preconditioning soak to be viable. All of the fuel tanks tested at EPA were sealed during the 

preconditioning period without incident. The purpose of sealing the fuel tank is to keep fuel and 

fuel vapor in the fuel tank, to the extent possible, during the preconditioning period. In the case 

where fuel was dispensed at a temperature below the soak temperature, it would be possible for 

the fuel tank to pressurize if the tank were sealed prior to the fuel temperature reaching the soak 

temperature. In this case, it would be acceptable to allow reasonable time for the test fuel to 

approach the soak temperature, prior to sealing, to prevent over-pressurization of the fuel tank. 

To prevent gross evaporation of fuel vapors during this period, the venting of the tank should be 

no greater than needed to prevent over-pressurization of the fuel tank. 

Provided that fuel is continuously in the tank during the durability testing, manufacturers 

may include this as part of the preconditioning soak. 

4.8.5 Fuel tank permeation– durability testing 

What Commenters Said: 

NMMA commented that the fuel tank permeation testing guidance provided for 

recreational vehicles should apply to marine fuel tanks as well.11 NMMA stated that this 

guidance retained the integrity of the permeation tests but greatly reduced the testing burden 

imposed on recreational vehicle manufacturers by providing optional ways to shorten and 

minimize the required test procedures. Specifically, NMMA and Inca Molded Products argued 

that fuel tanks not using surface treatment technologies, e.g., fluorination, to meet the permeation 

standards should not be subject to the slosh test because sloshing would not negatively impact 

the permeation of these types of tanks. In addition, NMMA and Inca Molded Products 

commented that the ultraviolet light exposure test does not make sense for fuel tanks installed 

inside marine vessels. With these modifications, Inca Molded Products expressed general 

support of the preconditioning durability procedures. 

Grady-White Boats commented that there is no need or benefit in requiring ultraviolet 

exposure testing of tanks that will not be exposed to sunlight once installed. Grady-White also 

commented that there is no benefit in slosh testing tanks that are not using surface treatment 

barriers to meet permeation requirements. 

10 Nonmetallic Fuel System Tubing with One or More Layers,” SAE Recommended Practice J2260, November 

1996. 

11 Dear Manufacturer Letter from Merrylin Zaw-Mon, Re: Alternative Test Procedures for Measuring Fuel Tank 

Permeation from Highway Motorcycles, ATVs, Off-highway Motorcycles and Snowmobiles, Document No. CCD05-14 (MC/ATV/OFMC/ICI/Snowmobiles), Aug. 17, 2005. 

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EMA commented that manufacturers should be allowed to request approval on a case by 

case basis in order to eliminate redundant testing or preconditioning requirements. This would 

include pressure cycling for tanks that have venting mechanisms that preclude a pressure 

increase or ultraviolet light exposure for tanks that are enclosed to prevent exposure to the sun. 

OPEI requested that EPA provide data to show that the durability test requirements properly 

represent real use simulation and can properly identify failed/compliant products at the end of 5-

year useful life. 

EMA commented that EPA should work with ARB to ensure that evaporative emission 

test procedures are aligned to the greatest extent possible. EMA and OPEI reasoned that aligning 

the EPA and California ARB durability test procedures would significantly reduce testing burden 

with no detriment to the environmental benefits of this rule. EMA and OPEI commented that 

EPA should accept testing performed following the California ARB procedures in TP-901. 

These test procedures include a shaker method for slosh. OPEI comments that a significant 

amount of the data utilized in the rule making utilized the California ARB TP-901 shaker method 

for slosh. 

EMA commented that tank systems that do not include features for pressure or vacuum 

retention, e.g. valves, should not require pressure-vacuum cycling as part of their durability 

demonstration. To allow harmonization with California ARB, EMA stated that the requirements 

for pressure and vacuum test values must be expanded to within 10 percent of design pressurevacuum limits and the number of cycles reduced to 1000 through either a change in the proposed 

requirements or an approved alternate without request by the manufacturer. 

OPEI commented that the UV test is not necessary on tanks made of materials containing 

UV inhibitors or nylon tanks which are resistant to UV rays. Additionally, the UV test should not 

be required on HDPE tanks that a manufacturer can prove that less than 50 percent of the tank’s 

external surface would be exposed to UV light. OPEI stated that clarity is needed in how the 

tank should be positioned for such a test. EMA commented that the specified UV criteria, 0.4 Whr/m2

/min, represents solar load on a clear day in the Southern U.S. EMA stated that the optional 

natural sunlight exposure does not specify where the exposure is conducted or the quality of the 

daylight raising concerns regarding equivalence between these options. In addition, the term 

“daylight hours” is not defined. In order to provide alignment with California ARB 

requirements, EMA commented that the UV requirements should be deleted. EMA argued that 

no data has been included in the record of this rulemaking that indicates that UV degradation of 

fuel tank permeation exists. 

With regard to EPA’s request whether additional durability tests are necessary, OPEI 

commented that there is no need to add additional durability tests because other safety standards 

exist (ISO/ANSI) covering requirements for tanks on Small SI products. In addition they stated 

that manufacturers are keenly aware of the critical durability testing and validation requirements 

in order to produce safe products. This can include cold drop testing, impact testing, pressure 

cycle testing, vibration testing, burst testing, leak testing, etc. New low permeation tank 

technologies will vary from manufacturer to manufacturer and the new technologies may involve 

new materials and processing equipment. OPEI commented that equipment manufacturers will 

be very cautious with these new technologies and continue with existing durability/validation 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

testing and may expand upon them with additional testing in order to validate the new low 

permeation fuel tank designs. Because the equipment manufacturers have a better understanding 

of the way the specific equipment is used, OPEI commented that the equipment manufacturers 

would be the best judge to determine what durability testing and validation testing is required. 

Therefore, OPEI commented that additional regulatory compliance could be complex and/or 

misrepresentative for specific equipment usage, and, therefore, should not be required. 

Inca molded products commented that, in some cases, molded parts made from new 

materials are able to meet all of the proposed durability requirements and pass the permeation 

test, but fail impact testing. Promens testified that they have worked with barrier layer materials 

that have increased the brittleness of the fuel tank. Promens presented information on the results 

of dart impact testing on these tanks showing ductile failures. Promens stated that use of the dart 

impact test, also known as the Bruceton Staircase Method, has proven to ensure a safe and 

reliable product and argued that marine fuel tanks must be able to pass this test. Promens argued 

that crash impacts testing such as described in SAE 5288 Snowmobile fuel tank impact test or 

SAE 51241 Motorcycle fuel tank lateral impact test do not directly test the integrity of the 

material. These tests only verify the integrity of the mounting of the tanks within structures 

because both SAE tests described have the tanks mounted to structures, and the tanks are not 

directly impacted. Promens commented that the arm impact test should be included as a 

preconditioning test or included it as part of the ABYC requirements. 

Letters: 

Commenter Document # 

NMMA 0688 

OPEI 0675 

Inca Molded Products 0700 

OPEI 0691 

Promens (hearing) 0642 

EMA 0691 

Grady-White Boats 0697 

Our Response: 

We agree with commenters that the durability testing requirements are not necessary for 

all fuel tank designs. In the proposal, we stated that one or more durability tests could be waived 

if we determine that omission of these tests would not affect the emissions from the fuel tank. In 

the guidance letter referenced above for recreational vehicles, we clarified that minimized 

durability testing may be appropriate for some tank materials and manufacturing processes. In 

the final rule we are specifically excluding metal tanks and other tanks using direct material 

solutions in the molding process from the durability test procedures by stating that they only 

apply to fuel tanks using surface treatments or post-processing barrier coatings as a permeation 

barrier. 

The durability test requirements are not intended to represent real use simulation of fuel 

tanks on equipment over the five year useful life. Rather these tests are intended to identify 

potential problems with the permeation barrier on fuel tanks. The slosh testing and pressure 

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vacuum testing are based on a draft recommended SAE practice and are intended to address 

surface wear and microcracking concerns. One million slosh cycles does not necessarily 

represent what each tank will see in-use, but does present a reasonable method for determining if 

an improperly applied treatment will wear off easily. The pressure-vacuum test provides a 

method for flexing the fuel tank to ensure that the coating will flex with the tank walls without 

easily breaking down. The purpose of the UV exposure test is to address concerns that certain 

treatments or coatings may break down when exposed to sunlight. In the case of surface 

treatments, UV additives do not protect the treatment, and certain UV additives may even 

hamper the proper application of the barrier. During testing, the amount of the surface exposed 

to UV light on the fuel tank should be representative of the largest amount of sunlight that the 

fuel tank would likely be exposed to. Good engineering judgment should be used, in the case of 

the direct natural sunlight option, to achieve a UV load comparable to the laboratory 

specification. 

We do not believe it is necessary to modify the durability procedures to achieve 

harmonization with California ARB. TP-901 already specifically allows the use of the EPA test 

fuel and slosh testing procedure. Most fuel tanks are not pressurized in use. For non-pressurized 

fuel tanks, California ARB does not require pressure-vacuum testing, making the EPA test the 

only one necessary. For pressurized fuel tanks, the EPA test is likely to be the more stringent 

procedure. Both EPA and California ARB allow manufacturers to request alternative test 

procedures provided that these procedures are equivalent or more stringent than the primary 

procedures. California ARB does not currently require UV exposure testing; however, 

performing this test would not be expected to disqualify a fuel tank from being compliant with 

the TP-901 procedures. Finally, as discussed above, many fuel tanks will not be subject to the 

EPA durability testing. 

The durability tests are not intended to address the integrity of the fuel tank itself, but 

rather to provide some assurance of the durability of the permeation barrier. We believe that 

manufacturers are best positioned to determine the appropriate methodology for determining 

product durability from a performance perspective. While consumers may not be aware of 

failures in the permeation resistance of a fuel tank, a fuel leak is quickly apparent. 

Manufacturers have a significant incentive to produce durable fuel tanks. In the marine industry, 

Coast Guard safety standards are augmented by consensus standards developed under the 

American Boat and Yacht Council. Land based equipment manufacturers have developed 

consensus standards such as ANSI and SAE recommended practices. In addition, several 

manufacturers have indicated that they have developed their own durability requirements. Given 

these factors, we are not expanding the durability testing procedures to address fuel tank 

integrity. 

4.8.6 Fuel tank permeation– test fuel 

What Commenters Said: 

OPEI commented that CE10 can be acceptable if the water content and aldehyde content 

of the ethanol is defined. They recommended that aldehydes and ketones be specified as being 

less than 100 ppm and that the water content be limited to 500 ppm. OPEI stated that splash 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

blending with denatured alcohol should be avoided due to the high water content and the 

negative effects (including repeatability) this can have on permeation tests with nylon fuel tanks. 

OPEI also commented that California ARB and EPA use different test fuels. OPEI 

requested that EPA and California ARB harmonize on a complete test procedure or that EPA 

accept California ARB test data (corrected for fuel types) as proof of compliance. In 

conjunction, OPEI commented that any EPA testing should use the same procedures as that used 

for certification. 

California ARB commented that CE10 should be the test fuel of choice because it is a 

known blend and is readily available. California ARB recommended that the proposed test fuel 

of EPA certification fuel with 10 percent ethanol (IE10) should not be adopted because IE10 has 

a lower permeation rate than CE10 and it is expected that its use would allow less efficient 

control technology to pass the fuel permeation test procedure. 

Letters: 

Commenter Document # 

OPEI 0675 

California ARB 0682 

Our Response: 

We are finalizing a test fuel of certification gasoline blended with 10 percent ethanol 

(IE10) for fuel tank permeation testing. The technological feasibility of the fuel tank permeation 

standards was largely based on testing using this test fuel. In addition, IE10 is much more 

representative of ethanol-gasoline fuel blends seen in use than CE10. While we are adopting a 

CE10 fuel specification for fuel lines to reflect established industry practice and the data 

available to set emission standards, these factors do not come into play for fuel tank testing. 

The California ARB test methods as specified in TP-901 for measurement of fuel tank 

permeation specify California certification gasoline or EPA certification gasoline, neither of 

which contain ethanol. We are not incorporating the California ARB method because we believe 

that the test fuel for fuel tanks should include ethanol. Gasoline containing ethanol is widely 

used in-use and ethanol can have a large effect on the permeation rates of fuel tanks. In the case 

where a manufacturer wishes to use a single test fuel for certification to the California ARB and 

EPA standards, the manufacturer may request approval of an alternative test fuel from California 

ARB as described in TP-901. Several executive orders have been issued by California ARB in 

which the test fuel contained ethanol. 

We do not believe that it would be appropriate to develop an adjustment factor for the use 

of fuel with and without ethanol for all fuel tanks. As shown in the RIA, the effect of ethanol on 

permeation varies greatly for different materials and permeation barriers used in fuel tanks. 

We are finalizing specifications for fuel ethanol blended into test gasoline based on 

standard industry practice. Specifically, we are incorporating by reference ASTM D4806-07 

which specifies a maximum water content, in the ethanol, of 1 percent by volume. When this 

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ethanol is blended into gasoline at 10 percent, this would result in a maximum water 

concentration of about 1,000 ppm. Because this is a maximum, manufacturers testing 

hygroscopic materials would be able to test using fuels with lower water content. ASTM D4806-

07 states that only gasoline compounds in the gasoline boiling range may be used as denaturants 

and specifically states that ketones may not be used as denaturants. This recommended practice 

makes no specific mention to aldehydes; however, commenters did not present information on 

why they believed that aldehyde content should be limited or if aldehydes are even commonly 

found in denatured ethanol. In any case, we believe that using the industry standard specification 

for denatured ethanol will provide for a test fuel that is representative of in-use blends. 

4.8.7 Fuel tank permeation– measurement method 

What Commenters Said: 

California ARB commented that the proposed fuel tank test procedures have no definitive 

way of determining the stability of the permeation rate for fuel tank testing. California ARB 

recommended that values be obtained for multiple days and a correlation coefficient be applied. 

The soak time for low-permeation fuel tanks may not be long enough to reach equilibrium. By 

not having this method for stability, the actual permeation rate may be higher than calculated. 

OPEI commented that the 14-day test period does not agree with California ARB practice 

and may be questionable engineering judgment. OPEI suggested EPA require that a minimum of 

4 weigh points be required in the 14-day period (including the 0-day measurement). If the data is 

suspicious, OPEI recommended that the test could be extended until some level of confidence is 

reached which may not necessarily require an additional 14 days. 

EMA commented that EPA should work with California ARB to ensure that evaporative 

emission test procedures are aligned to the greatest extent possible and recommends using the 

test procedures specified in TP-901. California ARB’s procedure requires daily measurements 

that ensure the permeation rate is at steady state by looking at the slope of the cumulative loss 

line which EMA argued is significantly more robust than the two data requirement proposed. 

For low permeation rates that challenge the precision of the balance employed, EMA 

recommended that it should be left to the discretion of the tester to extend the test in any 

reasonable increment as long as the result is expressed in the proper units. EMA argued that 

there is no need to specify that the test be lengthened in two week increments. In addition, EMA 

commented that a reduced testing burden should be determined using good engineering judgment 

and approved by the agency on a case by case basis. EMA stated that it is presumptuous to 

identify technologies in the regulatory context without the ability to allow equally effective 

technologies to be granted similar relief. 

California ARB commented that EPA should consider increasing test temperatures 

because, as permeation rates lower, accurate measurements become increasingly difficult. In 

addition, a higher test temperature would also shorten the preconditioning soak time. Newer 

technology increases a component’s resistance to permeation, thus taking longer to reach steadystate conditions. California ARB recommended a permeation test temperature of 40°C. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

OPEI commented that California ARB and EPA test procedures use different test 

temperatures. OPEI requested that EPA and California ARB harmonize on a complete test 

procedure or that EPA accept California ARB test data (corrected for temperature) as proof of 

compliance. In conjunction, OPEI commented that any EPA testing should use the same 

procedures as that used for certification. 

EMA commented that the required readability of 0.1 g or better is not feasible for testing 

larger tanks due to total scale capacity requirements. Promens expressed concern whether the 

weight change, due to permeation, for very large fuel tanks could be accurately measured. 

Promens stated that, in the case of the 50 gallon tank, there would only be a 3/100 of a percent 

change in weight and in the case of the 100 gallon tank, there would only be just over a 25/1000 

of a percent change in weight. 

HH&A commented that permeation mass measurements using ethanol containing fuels 

will produce different results if determined by the weight loss method and compared to the 

current SHED procedure. The issue here is that if one tests for permeation using a SHED, and 

uses the Federal calculations for mass emissions found in 40 CFR §86.143-96, the ethanol 

fraction of the permeate is reported as “equivalent gasoline.” The equivalent gasoline deletes the 

oxygen mass and lowers the hydrogen/carbon fraction from 3 to 2.3, both resulting in a lower 

than real mass calculation. As a result, if the SHED mass emissions measurement is compared to 

a gravimetric (weight loss) measurement, the SHED value will under-report the true value. 

HH&A recommended a revision to the SHED mass calculation where the ethanol 

contribution to permeation would be measured separately. A Flame Ionization Detector would 

be used to measures total hydrocarbons. This reading would then be corrected by subtracting the 

concentration of ethanol measured by the gas chromatograph (GC). This corrected reading 

would be used to compute non-ethanol hydrocarbon mass emissions. To this value you would 

add the ethanol concentration converted to mass using the true mass of the ethanol molecule. 

EMA stated that the NPRM directs the tester to close the door and “record the time” when 

the enclosure is closed at the beginning of the weight loss test. However, EMA recommended 

that both the time and date should be recorded. 

Letters: 

Commenter Document # 

California ARB 0682 

EMA 0691 

OPEI 0675 

HH&A 0640 

Promens (hearing) 0642 

Our Response: 

We agree with commenters that making daily recordings of the fuel tank weight is 

consistent with good engineering practices. These daily mass measurements can be used to 

determine the stability of the permeation rate of the fuel tank and can help identify if anything 

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unusual is occurring during the test such as a lost seal during testing. The test procedures in TP901 require that the weight loss test continue until the correlation coefficient (r2

), from a plot of 

the cumulative daily weight loss versus time for 10 consecutive 24-hour cycles, is 95 percent or 

greater. We believe this approach gives testing facilities flexibility for basing the length of the 

test on good engineering judgment rather than a fixed time period. Therefore, we are adopting 

this general method of using daily measurements to determine the length of the test, with one 

modification. The California ARB method would require test facilities to make measurements 

over at least one weekend. We believe that weight loss measurements can be suspended for 

short periods of time without a negative impact on the test. Therefore, we do not require that the 

11 weight loss measurements (including the 0-hour measurement) be on consecutive days 

provided that measurements are made on at least five different days of any given seven day 

period of the test. Measurements must be made at roughly the same time on each test day. 

We are also adopting the sensitivity requirements for the weight loss measurements 

specified in TP-901. For mass measurements more than 6200 grams, the sensitivity of the 

balance remains at 0.1 grams, as proposed. However, for smaller tanks, more sensitive 

equipment is needed to accurately measure the permeation using the weight loss method. In the 

data collection for this rulemaking, for instance, a balance with a sensitivity of 0.001 grams was 

used for fuel tanks less than 1000 grams. Therefore, we are specifying a minimum sensitivity of 

the balance of 0.01 grams for mass measurements between 1000 and 6200 grams and 0.001 

grams for mass measurements less than 1000 grams. 

At this time, it appears that required readability of 0.1 grams or better is not feasible for 

mass measurements larger than roughly 35 kilograms due to total scale capacity requirements. 

However, a fuel tank within this weight limit may be used to represent a family of larger fuel 

tanks provided that the smaller fuel tank represents a “worst case” configuration for that family. 

In addition, manufacturers may request the use of other procedures provided that these 

procedures are equivalent or more accurate than the primary test procedures or if it can be 

demonstrated that the use of the alternate test procedure would not affect the ability to 

demonstrate compliance. In the case of SHED testing, the manufacturer would need to 

demonstrate that it is correctly accounting for the ethanol content in the fuel. One approach may 

be to use a procedure similar to that described above in the HH&A comments. 

We modified the test procedures to specify that the date should also be recorded when the 

enclosure is closed or at other steps when the time is recorded. 

4.8.8 Fuel tank permeation– other 

What Commenters Said: 

Honda requested clarification on §1060.520(b)(5)(i) and (ii), asking if this test is 

necessary, specifically related to when the fill pipe / hose is part of the tank test, tested as a 

separate part required to meet a 15 gram standard, or simply not covered because it does not 

contain liquid fuel. In addition, Honda requested clarification as to why the fuel cap would need 

to meet a permeation standard at the top of a 12 inch or longer fill pipe / hose when, like the fuel 

fill, it is not exposed to liquid fuel. Promens commented that this provision complicated the fuel 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

tank testing and recommended that fuel caps should not be tested as part of the fuel tank unless 

the cap is directly part of the tank either by threads or mechanical attachment. 

Yamaha noted that the requirement in §1060.520(b)(5)(i) of the proposal it indicates that 

filler necks that are under 6 inches above the top of the tank be tested with the filler cap as part 

of the tank system. Yamaha commented that this 6 inch requirement will unfairly target low 

gunwale height (small) boats and low profile bass boat designs with small installed fuel tanks. 

Yamaha argued that EPA has not made any demonstration as to the need of the 6 inch minimum 

requirement in or prior to this proposal and that this 6 inch criteria will cause all builders of small 

gunwale height boats a great expense for testing or design changes for no emission reduction 

gains. Yamaha requested that the 6 inch minimum height be removed from the test requirement 

for compliance testing of the fuel tank. 

EMA commented that the reference to dry sand in the reference tank should be replaced 

with glass bead because sand is known to adsorb moisture and may not be appropriate. MIC 

commented that because the intent of this subsection describing the reference tank is to deal with 

changes in “buoyancy” caused by changes in atmospheric pressure, the same correction could be 

accomplished mathematically based on the difference in air density measurements between tests. 

MIC argued that this would avoid the cost and space required to prepare and store reference 

tanks. MIC recommended the addition of a new subsection stating that, as an alternative, 

manufacturers may calculate the weight change associated with the permeation test run without 

the use of the reference tank method by determining the air density (from barometric pressure) 

during the initial weighing of the sealed test tank under 1060.520(d)(1), using the measured 

value as Minitial, and then replacing the procedure described in 1060.520(d)(7) with a 

determination of Mfinal from the buoyancy-corrected weight for the sealed test tank calculated 

based on the change in air density between the initial and final measurements and the known 

volume displaced by the tank. 

OPEI noted that 1060.520(b)(5) allows non-fuel cap openings to be sealed with nonpermeable coverings or methods. OPEI recommended that an allowance should be made to not 

have the openings machined into the tank for permeation testing because this would be easier for 

testing and would only produce insignificantly higher permeation rates when compared to nonpermeable sealing methods. OPEI specifically recommended that grommets not be considered to 

be part of the fuel tank. OPEI stated that this would harmonize with California ARB’s TP901and requested that EPA add California ARB language from TP-901 in this regard. 

California ARB commented proposed permeation test procedure and standards for tanks 

may exclude emissions from fittings, fuel pickup tubes, and fill caps. California ARB 

recommended that we adopt a diurnal test procedure that measures permeation, evaporation, and 

liquid leaks. During emissions inventory development testing, California ARB conducted 

diurnal testing to check the integrity of the tank components in addition to permeation barriers. 

California ARB reported that the data shows significant sources of evaporative emissions from 

components in addition to permeation. 

OPEI commented that 1060.520(d)(10) has a typo in the last sentence. It currently reads 

“In this case, repeat the steps in paragraphs (b) (8)...” It should read “In this case, repeat the 

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steps in paragraphs (d) (8)...” EMA commented that the reference, in §1060.521(c), to 

§1060.520 is not adequate because several aspects of §1060.520 are not applicable. EMA 

commented that the specific reference should be to §1060.520(d). 

Letters: 

Commenter Document # 

MIC 0701 

Yamaha 0721 

California ARB 0682 

EMA 0691 

OPEI 0675 

Honda 0705 

Promens (hearing) 0642 

Our Response: 

The general purpose of §1060.520(b)(5)(i) and (ii) is to describe how the fill inlet must be 

sealed for a tank permeation test. We are simplifying this requirement to state that, if the fuel 

cap is not directly mounted on the fuel tank, then the opening may be sealed with a nonpermeable covering. We are concerned that the fuel tank manufacturer may not necessarily be 

aware of the configuration of the fill neck once it is installed in a marine vessel or piece of 

equipment. If the fuel cap is mounted directly on the fuel tank, we consider it to be part of the 

fuel tank and that it should be included in the fuel tank permeation test. We do allow alternatives 

to installing the cap on the tank during the test, including separate permeation testing of the fuel 

cap and the use of a default value for fuel cap permeation. 

Based on the concern that sand may adsorb moisture, we are changing the regulation to 

refer to glass bead rather than dry sand for use inside of the reference fuel tank. We believe that 

an actual weight measurement on the reference fuel tank is the most direct and accurate method 

for correcting for buoyancy effects that may occur during testing. In addition, the reference tank 

inherently corrects for changes in humidity that may affect the amount of water absorbed by the 

fuel tank. Therefore, we are not including a buoyancy correction calculation as an alternative. 

To simplify the test procedures, we are specifically excluding grommets from the fuel 

tank permeation testing. In this case, and for hose connections, the manufacturer has the option 

of simply not drilling the opening as an alternative to sealing the opening with an impermeable 

plug. Fuel caps, and other components mounted directly on the fuel tank, are included under the 

permeation standard. We are concerned that requiring a diurnal test procedure would add 

significant complexity and cost to the tank permeation testing without a significant 

environmental benefit. This is especially true for fuel tanks that are not pressurized in-use and 

have fittings that are not designed to withstand the tank pressures that may occur during the test. 

The incorrect reference (in §1060.520(d)(10)) to paragraphs (b)(8) through (9) has been 

removed. The reference (in §1060.521(c)) to §1060.520 is correct. A reference specifically to 

§1060.520(d) would unintentionally exclude the preconditioning fuel soak. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

4.8.9 Diurnal 

What Commenters Said: 

Honda noted that §1060.525(a)(5) proposes that the test of a canister should begin with 

the canister at full working capacity, exposure of the canister to one diurnal cycle and then 

initiation of the test. Honda commented that this test will not be representative of some canisters 

that will not reach full saturation under normal diurnal conditions. Honda argued that this is an 

issue of concern for both small engines and marine engines and suggested that this issue needs 

further, more in-depth evaluation. 

California ARB commented that the proposed diurnal temperature profile may not be 

stringent enough to replicate the higher temperatures that commonly occur in California and 

other Southwestern states. Because many marine spark-ignition vessels spend the majority of 

time exposed to the sun, California ARB expects that fuel temperatures will likely exceed the 

proposed 25.6oC to 32.2oC fuel temperature profile. California ARB commented that a 

temperature profile of 65 to 105 degrees Fahrenheit (oF) seems more appropriate for California 

and is currently evaluating the diurnal temperature profile. California ARB requested that EPA 

adjust the proposed temperature profile when the data becomes available. 

California ARB commented that the proposal to fill the fuel tanks to 40 percent capacity 

is not consistent with the California established procedure of filling the fuel tanks to 50 percent 

capacity for diurnal testing. For harmonization, California ARB recommended that EPA should 

either modify the test procedure to require that fuel tanks be filled to 50 percent capacity or to 

allow California testing to meet the proposed EPA requirements. 

California ARB commented that the proposed three-day diurnal cycle for measuring 

emissions from marine vessel tanks configured with carbon canisters may not be long enough to 

determine canister stability. California ARB recommended a seven-day diurnal cycle to ensure 

canister stability. 

EMA commented that the ASTM method cannot be used for measurement of butane 

working capacity in a carbon canister because the method requires a specific shaped test vessel, a 

specific amount of carbon, and temperature controlled water bath. EMA argued that the ASTM 

method should not be referenced except when specifically defining the bulk characteristics of the 

carbon itself. EMA recommended that the Butane Working Capacity be determined using the 

procedure defined in ARB TP-902 Appendix A. 

Delphi stated that it agrees with the proposed diurnal fuel temperatures for the fuel tanks, 

but suggested that there may be challenges associated with running the proposed test procedure. 

Delphi stated that breakthrough amounts may exceed limits of a typical SHED flame-ionization 

detector. Therefore, a purged slave canister would need to be weighed and connected to the air 

inlet of the test canister to measure breakthrough amount. By having the slave canister outside 

the SHED, the permeation of the fuel tank would not contribute to the diurnal emissions. Delphi 

stated that the slave canister may need to be manually changed to allow back purging of test 

canister; otherwise, complicated valving and switching is required. Delphi also noted that the 

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Chapter 4: Evaporative Emissions 

SHED ambient temperature needs to be controlled based on fuel temperature which is different 

from typical automotive testing where SHED temperature is controlled as a function of ambient 

temperature in the SHED. 

Letters: 

Commenter Document # 

Honda 0705 

California ARB 0682 

EMA 0691 

Delphi 0638 

Our Response: 

It is not clear why Honda believes that a carbon canister on a marine vessel may not 

reach saturation under normal diurnal conditions. It is common for marine vessels to remain 

unused for extended periods of time. Therefore, effects such as active purge or fuel draw down 

in the tank, which require engine operation, cannot be relied on to purge the canister regularly at 

short intervals. Data in the RIA show that passively-purged carbon canisters subject to a multiday diurnal cycle eventually reach saturation. A large enough canister to never reach saturation 

would be cost-prohibitive and too large for most marine applications. Therefore, we believe that 

the carbon canister must begin loaded and then subjected to a passive purge cycle prior to 

performing diurnal emission measurements. 

The temperature profile for marine fuel tanks is based on the same ambient temperature 

profile used, in EPA test procedures, for automotive applications. It is reasonable to expect that 

boats would experience similar summer day temperatures as cars and trucks. As demonstrated 

by data in the RIA, fuel temperatures profiles in marine fuel tanks typically have less variation 

than ambient air temperature due to inherent insulation of the fuel tank in the boat, influence of 

water temperature (for boats stored in the water), and thermal inertial of the fuel (especially in 

larger fuel tanks). As a result we based the diurnal test temperatures on fuel temperature and 

adjusted for the above effects. 

It should be kept in mind that the test procedure is a combination of different parameters 

that affect the measured diurnal emission rate. These variables include fuel specifications and 

fill level as well as the temperature profile. The diurnal emission standards are based on 

measured emissions using the emission test procedures established in this rule. If the test 

parameters were to be changed, the numerical level of the standards would need to be adjusted as 

well to achieve the same stringency. In the event that California ARB develops a diurnal test 

procedure for marine vessels, we would need to consider all of the above test parameters before 

determining if data collected on that future test cycle will be acceptable for certification to the 

EPA standard. To the extent that there are differences in test procedures, we would need to 

approve those changes under §1060.505(c). 

We believe the diurnal test procedures are appropriate for demonstrating the in-use 

control capability of anticipated emission control technologies. An overly high temperature 

profile could cause poor test results for a given control technology, such as sealed tanks with 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

pressure relief, even though this given control technology would be expected to achieve 

significant emission reductions in use. The fill level and test fuel specifications are based on 

those used today for automotive testing, and we believe these parameters are also representative 

of in-use conditions for marine vessels. 

We have not seen evidence that a seven-day diurnal cycle would ensure canister stability. 

In our test procedure, the canister begins in a loaded condition then a single passive purge event 

is run. Data in the RIA suggests that, once these conditions have been achieved, that a relatively 

stable emissions profile is achieved. We believe that a seven day test would be overly 

burdensome without providing significant additional useful information. We do recognize that 

additional diurnal cycles may be warranted for control strategies that depend on regular engine 

operation such as designs that are based on active purge, or even running loss conditions. This 

may be appropriate for equipment types that are used more regularly than marine vessels. 

We agree with EMA that ASTM D5228-92 is intended for determining carbon working 

capacity rather than canister working capacity and is therefore not an appropriate method for 

loading a canister prior to a diurnal emission test. As a result, the diurnal emission test 

procedures have been revised to include a canister loading procedure, for marine applications, 

based on the method in TP-902 for small off-road equipment. 

Delphi commented that the diurnal emissions from marine fuel tanks may be too high to 

be measured by standard equipment in existing SHEDs and suggested an alternative procedure 

based on the use of a slave canister. It should be noted that the diurnal emission data presented 

in the RIA for marine fuel tanks was based on SHED testing with a flame-ionization detector. In 

the event that a manufacturer was not able to perform the test procedure in the regulations, they 

would be able to request EPA approval of an alternative method provided that this method is 

equivalent to the primary method. 

4.8.10 Running Losses (temperature measurement) 

What Commenters Said: 

EMA commented that, for running loss testing, the fuel tank temperature must be 

stabilized prior to running the test such that fuel stabilization is not inadvertently included in the 

measured result. However, EMA argued that the requirement that the fuel in the tank be within 

2°C of (but not exceeding) the ambient temperature is overly prescriptive. EMA recommended 

that the requirement be revised to indicate the use of good engineering judgment to determine 

that the fuel temperature in the tank has stabilized, with the caveat that the measured temperature 

rise cannot be adjusted to account for perceived changes due to stabilization. In addition, EMA 

commented that fuel temperature in the tank that is not a result of engine operation, such as sun 

heat loading, should not be included in the temperature rise associated with determination of 

running loss control. If, using good engineering judgment, EMA stated that a manufacturer can 

demonstrate the fuel tank temperature variation associated with conditions other than running the 

engine these variations should be allowed to be deleted from the running loss temperature rise 

assessment. 

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EMA argued that the proposed testing conditions are not viable and do not represent the 

appropriate measure of fuel tank temperature change associated with running the engine. 

According to EMA, the set of conditions needed to run an outdoor running loss test are 

unacceptably limiting, large portions of the year will not meet the combinations of conditions, 

and the number of days that can be used for testing will be severely limited. Specifically, EMA 

recommended that the maximum acceptable cloud cover specified in §1060.535(a)(3)(iv) should 

be deleted in its entirety. 

EMA requested that the final rule include the option to use a laboratory test procedure, 

stating that a lab test would be more repeatable and less subject to variation due to ambient 

conditions. Additionally, EMA commented that these procedures should include an option to 

record the fuel temperature of an equivalent unit exposed to the same ambient conditions but 

without the engine running. The reported temperature rise would be the difference between the 

temperature of the running unit and the non-running unit. EMA commented that the requirement 

to include solar loading in the determination of an equivalent indoor test is not appropriate, and 

that temperature rise criteria should not include effects that are not related to engine operation, 

such as solar loading. 

Letters: 

Commenter Document # 

EMA 0691 

Our Response: 

As discussed above, we are not finalizing an option to comply with the running loss 

standard by demonstrating that only a minimum fuel temperature rise occurs during engine 

operation. Therefore, the above comments are not relevant because we are not finalizing a test 

procedure for measuring fuel temperature changes during engine operation. 

4.8.11 Diffusion 

What Commenters Said: 

EMA commented that there is no need for a specific requirement related to diffusion 

emission controls and therefore no need for a procedure to test diffusion emissions. However, in 

the case that a diffusion test is required, EMA made the following recommendations: 

- Manufacturers also should have the option to test using the gasoline specified for testing 

in 40 CFR Part 1060.501. The option to test with the gasoline specified in §1060.501 

would allow the manufacturer to conduct diffusion testing with the same stabilized fuel 

tank utilized for permeation testing. 

- The requirement to use a fully loaded canister attached to the fuel tank in a way that 

represents a typical in-use configuration is not appropriate. No testing was performed 

during the development of the NPRM with a carbon canister, and the implications of the 

canister loading are not clear. We recommend the test be conducted with a fully purged 

canister or, at the maximum, a 50% filled canister. In addition, California ARB’s TP-902 

method should be used to determine canister working capacity. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

- The length of the “stabilization period” must be defined. EMA recommends that the 

stabilization period definition require that both the liquid fuel and enclosure temperature 

should be maintained at the specified temperature range for 30 minutes. While required 

for accurate testing, purging the SHED introduces fresh air to the enclosure that is not at 

the specified temperature. A re-stabilization of the SHED and liquid fuel temperature 

after purging for at least 15 minutes should be included. 

- The requirement to collect emission measurements for 6 hours is overly prescriptive. 

EMA recommends a change to allow collection of emissions measurements for at least 6 

hours but no more than 24 hours. 

Letters: 

Commenter Document # 

EMA 0691 

Our Response: 

As discussed above, we are not finalizing a diffusion standard. Therefore, the above 

comments on the test procedures are not relevant because we are not finalizing a diffusion test 

procedure. 

4.9 Small business issues 

What Commenters Said: 

Tohatsu commented that it is quite a tough job for a small manufacturer like itself who 

has total employees of less than 500 people to redevelop and set calibration fuel, ignition timing, 

etc. and also comply with evaporation requirements. Although Tohatsu understands that these 

requirements are necessary, they noted that it is a very time consuming, and expensive, process 

for a small company to meet. Tohatsu commented that the time frame should be extended as 

much as possible to give small manufacturers a realistic chance to comply with the new 

regulations. Unlike many of their competitors that have other divisions in cars and motorcycles, 

Tohatsu produces only outboards. Because of this, Tohatsu commented that it does not have the 

same resources to be able to comply with new regulations as quickly as other companies. 

Premier Marine commented that the diurnal system requires a pressurized fuel system 

and they would be very cautious regarding the safety of this technology for use in the marine 

market and could lead to possible hazardous conditions. As a small business, they commented 

that they do not have the resources to engineer and test the proposed canisters. It will be very 

costly to implement and they would need more time to implement the change. 

NMMA noted that EPA acknowledges the challenges faced by the small boat builders 

and requested comment on a three-year phase-in (33-66-100 percent) for the diurnal emission 

standards over model years 2010-2012. NMMA commented that a phase-in approach is not 

practicable for boat builders. Instead, NMMA supported an additional two years of lead time for 

compliance, i.e., until model year 2013, for small businesses to allow for sufficient time for these 

business to gain experience with carbon canisters. NMMA commented that small businesses 

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with 500 employees or less should be eligible for this relief. NMMA also supported additional 

lead time so that ABYC could work on standard practices for canisters and address possible 

pressurization issues. 

Grady-White Boats provided comments to EPA after the close of the comment period on 

a phase-in of the diurnal emission standards for small manufacturers. Grady-White noted that 

they are convinced that the fairest method to implement the diurnal controls is on a percentage 

basis. This treats all boat builders on an equal basis and does not create competitive advantages 

or disadvantages for anyone. 

To demonstrate the inequities created by an allowance system, Grady-White suggested 

EPA consider a comparison of a low volume builder of a larger sized boat to a high volume 

builder of a small model boat. Both builders have total wholesale dollar sales of $50 million a 

year. Builder A builds an 18' center console model that wholesales for $19,000. This requires 

sales of 2,632 units to make the $50 million in sales. Production level would be about 50 boats a 

week. Under an allowance system discussed by the EPA this builder has to install diurnal 

controls on 1,832 boats the first year. Builder B builds a 33' boat that wholesales for $259,000. 

This requires 193 boats to get annual sales of $50 million. Production would be about 3.7 units 

per week. Under the allowance system discussed by EPA the builder would not have to install 

controls on any boats until the last year of the phase-in period. 

Grady-White noted that the two companies of equal sales figures are treated completely 

different regarding the impact of the diurnal control phase-in allowance. This is clearly unfair to 

the one builder. A straight percentage based approach as recommended by NMMA (30/60/100) 

treats both the above businesses fairly and equally. In the above example, both builders have 

only one model upon which to engineer the changes. The engineering cost will be 100% in the 

first year for builder A while builder B can spread the re-engineering cost over a three year 

period. 

Grady-White noted that they have also struggled to understand the EPA's perspective 

from the compliance/enforcement side. If a builder has to keep records to prove compliance on a 

percentage basis, or on an allowance basis, there seems to be no difference. The builder will 

have to maintain these records and be able to produce them upon the request of the EPA. The 

boats can be clearly labeled as within the percentage required to have controls as easily as they 

can be labeled as within the allowance. They fail to understand how the percentage proposal 

requirement places any additional burden upon the EPA. 

Grady-White Boats also commented on the impact and challenges the proposed rule 

creates for small businesses. They commented that the rule creates many demands for reengineering, paperwork, record keeping and cost increases for our customers. They believe it is 

vital to keep the new requirements from becoming a paperwork and reporting nightmare for the 

small businesses that are the backbone of the boat building industry. Grady White highlighted 

the engineering resource burden to redesign and/or modify existing tooling to accept canisters 

and estimated that 100 man hours per model will be needed to design, prototype, train production 

associates, and document the fuel system changes on each model. The builders commented that 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

small businesses do not have the engineering stuff to handle these extra demands in such a short 

time. 

NMMA noted that it is conducting outreach to the boat building community to ensure 

that all affected businesses are aware of the new regulation and its implications. NMMA urged 

EPA to work with the SBA to develop a schedule for workshops across the country to ensure that 

small businesses understand the requirements of the standards and the implementation dates. 

ABYC noted one concern it shares with NMMA is the education of the non-NMMA 

builders. The US Coast Guard has a database with over 4,000 registered boatbuilders. ABYC is 

geared toward all builders with the ultimate goal of safer product on the water. With its 15 year 

track record of educating and certifying personnel to our standards, ABYC commented that it 

will be a crucial asset for educating the approximately 3,600 builders that remain uncertified by 

the NMMA. ABYC noted that with the proper funding, it can help educate boatbuilders, on a 

much broader scale, to the upcoming EPA requirements as well as ways to make a boat safer. 

Letters: 

Commenter Document # 

Tohatsu (hearing) 0642 

Premier Maine Inc. 0613 

NMMA 0688 

ABYC (hearing) 0642 

Grady-White Boats 0677 

NMMA 0739 

Grady-White 0750 

Our Response: 

With respect to the comments on additional time for small manufacturers to meet the 

evaporative standards, it can be noted that EPA is delaying implementation of a number of the 

evaporative emission standards for all manufacturers. EPA is delaying implementation of certain 

hose requirements originally scheduled for implementation in 2009. The requirements contained 

in the final rule for under cowl hose will be phased in between 2010 and 2015, and the primer 

bulb will have until 2011 to comply. In addition, EPA is delaying the diurnal requirements 

which were proposed for 2009 for portable tanks and PWCs until 2010. In addition, EPA is 

delaying implementation until July 31, 2011 for other installed tanks, with a 50 percent phase-in 

requirement for the first year. As noted below, EPA is also adopting a diurnal allowance 

program for small-volume boat builders as an alternative to the phase-in. EPA believes these 

delays will provide sufficient lead time for all manufacturers to comply, whether large or small. 

(See Section 4.3 of this document for further discussion of the feasibility and lead time for the 

evaporative emission standards for Marine SI engines and vessels.) 

As noted above, manufacturers expressed concern that many small boat builders may 

need additional time to develop installation procedures and install carbon canisters in their boats. 

To address this, we are establishing an interim diurnal allowance program that will give 

additional time for small-volume manufacturers for a certain number of boats during the first two 

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years of the program. Under this program, each small-volume boat builder will be allowed to 

sell these boats without the diurnal emission controls that would otherwise be required. This 

allowance program applies only to boats with installed fuel tanks that are expected to use carbon 

canisters to meet the diurnal emission standards. Therefore, it does not apply to portable fuel 

tanks or personal watercraft. If the small-volume boat builder chooses to use this allowance 

provision, then the 50 percent phase-in for the first year, as noted above, would not apply. Each 

small-volume boat builder will have a total of 1,200 allowances that may be used, at the 

manufacturer’s discretion, for boats produced from July 31, 2011 through July 31, 2013. For 

instance, a small manufacturer could produce 800 boats in the first year and 400 in the second 

year without diurnal emission controls. For most small-volume boat builders, we expect that this 

allowance program will result in an additional year or two of lead time for them to address 

potential installation issues related to carbon canisters. 

In response to the comments on conducting outreach to boat builders, EPA agrees that 

such a process is important to ensuring the success of implementing the new requirements. With 

potentially thousands of boat builders, it will be necessary to use a variety of methods to make 

sure that all affected manufacturers are aware of the new requirements. EPA expects to explore 

working with all interested parties, including trade organizations and other government agencies, 

to educate boat builders on the requirements that will come into effect as a result of the new 

evaporative emission standards for marine engines and vessels. 

With regard to the comments on the amount of paperwork and reporting required under 

the new standards, EPA has designed the program in a way that allows boat builders that use 

certified components (i.e., hose, tanks, and diurnal systems) to not have to certify with EPA at 

all. This would be synonymous with the current program in which boat builders that use 

certified engines have no requirement to submit any information to EPA. If a boat builder 

chooses to certify its own fuel line, fuel tank, or diurnal system, they will be required to certify 

with EPA and submit all of the information required as part of that process. However, EPA 

expects that most boat builders will purchase certified components, allowing them to avoid 

submitting any information to EPA. Boat builders participating in the ABT program for fuel 

tanks would also be required to certify with EPA. Because participation in the ABT program is 

voluntary, only those boat builders choosing to earn or use credits for their boats would need to 

certify with EPA. 

4.10 Other issues 

Comment Response 

OPEI commented on §1060.301 that more detail is 

required from EPA as to what is acceptable QA data. 

OPEI noted, for example, thickness checks, FTIR data, 

iodine checks for coextruded and asked what level of 

data would be acceptable to EPA. Similarly, EMA 

commented on §1060.301, saying that the section is 

vague, and should include examples of expected testing 

such as the following: “For example, you must conduct 

production quality testing in order to confirm barrier 

layer thickness or materials utilized are as specified.” 

We believe it is most appropriate to rely on broad 

language requiring manufacturers to perform qualityassurance procedures relative to the evaporative 

emission standards without requiring specific 

measurements, sampling rates, or other detailed 

specifications. We would expect all manufacturers to 

take steps today to ensure that their products meet 

certain quality and performance specifications. We 

simply want manufacturers to use good engineering 

judgment to factor emissions compliance into their 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

ongoing effort to ensure quality production. This might 

involve emission measurements, but it may alternatively 

involve a series of measurements and inspections not 

directly related to the applicable emission standard. 

NMMA and Mercury Marine noted that EPA’s preamble 

states that manufacturers will not be required to perform 

in-use testing or production-line testing for evaporative 

emission standards. However, EPA then states that “we 

may pursue testing of certified products to evaluate 

compliance with evaporative emissions standards” and 

includes proposed §1060.301. This section requires 

manufacturers to “test production samples or otherwise 

verify that equipment or components . . . are as specified 

in the certificate of conformity.” (as proposed in 

§1060.301(a)). NMMA and Mercury Marine 

commented that the inclusion of this provision not only 

contradicts EPA’s statement in the preamble but it also 

seems inconsistent with the design-based certification 

option. Given that EPA can always use the SEA 

program, NMMA and Mercury Marine recommended 

that EPA delete this provision from the rule. 

We are not adopting specific requirements for in-use 

testing or production-line testing for evaporative 

emission standards. This contrasts with outboard and 

personal watercraft engines where we have adopted 

requirements for both of these types of testing. The 

Clean Air Act allows us to do any amount of testing to 

confirm that certified products meet applicable 

standards. Without routine testing after certification 

from manufacturers, we may find the need to do some of 

this testing ourselves. As described under the preceding 

comment, the provision requiring evaluation of 

production samples is intended to require broadly that 

the manufacturers take steps to ensure that their products 

are meeting quality specifications for emission-related 

compliance at the same time that they are evaluating 

these components for other purposes. 

Honda recommended that we clarify the design-based 

certification options in §1060.240 to emphasize that any 

of the listed technologies are acceptable for certification 

(not all of them). 

We agree with the comment and have changed the 

regulation accordingly. 

OPEI supported the provisions as stated by EPA to align 

exemptions for both exhaust and evaporative 

requirements for the same product. The exemptions for 

evaporative requirements must be for products where the 

exhaust requirements have already been exempted for 

the reasons stated within the provision. Equipment 

manufacturers may need to apply for exemptions for 

equipment that includes new evaporative emission 

control technology but does not include new exhaust 

emission technology. As such, a program to allow for 

exemptions associated with evaporative only provisions 

independent of the engine manufacturer must be 

allowed. 

We understand this comment as supporting the proposed 

approach. We are finalizing these provisions as 

proposed. 

EMA noted that equipment manufacturers may need to 

apply for exemptions for equipment that include new 

evaporative emission control technology, but does not 

include new exhaust emission technology. As such, 

EMA commented that a program to allow for 

exemptions associated with evaporative only provisions 

independent of the engine manufacturer must be 

included in the final regulation. 

We specifically proposed that the testing exemption is 

one of those cases where manufacturers may need an 

exemption from evaporative requirements even though 

the engine would not be exempted from exhaust 

emission standards. We are therefore adopting the 

regulatory language as proposed. 

OPEI commented that EPA should clarify §1060.201. 

OPEI noted that the certificate of conformity will list an 

effective date (signature date). The manufacturer may 

not introduce into commerce before this date but may 

produce equipment/engines prior to the effective date. 

We are adopting provisions in §1068.103 to clarify that 

manufacturers may produce engines or fuel-system 

components after submitting an application for 

certification, subject to certain conditions. This is 

consistent with longstanding practice. 

The Massachusetts Marine Trade Association 

commented that the recreational marine industry is 

staggering due to several recent mandates by EPA. 

They cited damage to boat engines due to the addition of 

ethanol to gasoline, loss of engine system lubricity due 

We have made great efforts to address NMMA’s 

concerns with the regulations, as described throughout 

this document. 

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to introduction of ultra low sulfur diesel fuel, permitting 

of tens of millions of boats due to incidental discharges, 

and ongoing expenses and regulations imposed on small 

marinas and boatyards to come into compliance with the 

Clean Water Act and the Resource Conservation and 

Recovery Act. The Massachusetts Marine Trade 

Association requested that EPA work with NMMA to 

implement the new regulations. 

EMA commented that the combination of engine and 

equipment requirements as currently set forth in Part 

1054 is confusing to the regulated parties. In order to 

address this issue, EMA commented that §1054.20(a), 

(c), and (d) should be deleted and §1054.20(b) should be 

revised to state “All equipment utilizing engines subject 

to the exhaust standards of this part must meet the 

evaporative standards of 40 CFR Part 1060. 

We believe this section, including the offending 

paragraphs, provides a useful summary for equipment 

manufacturers who might be reading part 1054. (This 

might often occur since these companies in many cases 

also certify with respect to exhaust emissions.) These 

paragraphs also allow us to clarify what provisions apply 

for fuel systems used with marine vessels or motor 

vehicles. 

EMA commented that §1054.110 is confusing and must 

be clarified. While the introductory paragraph indicates 

that this section provides standards applicable to 

handheld engines, §1054.110(c) and (d) specifically 

state that they are applicable to non-handheld 

equipment. In order to avoid confusion, EMA 

commented that the handheld provisions should be 

segregated from the non-handheld provisions. 

Accordingly, the references to 40 CFR Part 1060 that 

apply to each industry could be more clearly identified. 

We agree with this suggestion and have revised the final 

rule accordingly. 

EMA commented on “Are there interim provisions that 

apply only for a limited time?” EMA commented that 

§1054.145(d) and (e) pertain exclusively to nonhandheld 

non-integrated equipment manufacturers and therefore 

appear to be misplaced. EMA commented that these 

paragraphs should be deleted in their entirety. 

Since part 1060 applies broadly to different categories of 

nonroad equipment, it would also be very confusing to 

move these provisions to part 1060. Since the 

provisions related to emission credits are already in part 

1054, we believe it is quite appropriate to place these 

provisions for equipment manufacturers in part 1054. 

Moreover, in many cases equipment manufacturers also 

certify with respect to exhaust emissions, so placing 

these provisions in part 1054 should involve a minimum 

of confusion. 

EMA commented that §1060.202(a) and (b) appear to 

contain a typographical error. The word “through” 

should be deleted and replaced with “....standards 

specified in §1060.105, ...” in both paragraphs. 

We agree that the text was not correct. The proper 

wording is “§§1060.102 through §1060.105.” 

EMA commented that §1060.240 is incomplete. Part 

1060 includes requirements for running loss controls and 

diffusion controls that are not included in the NPRM, 

but are nonetheless required. EMA recommended that 

EPA develop a table outlining the requirements for the 

different regulated industry segments, as defined in 

§1060.1, and defining the demonstration requirements 

for each control element required. 

We have attempted to lay out the full set of requirements 

and responsibilities for different manufacturers in 

§1060.1 and §1060.5. We did not attempt to use 

§1060.240 to define design-based certification options 

for every standard and every technology. The list of 

technologies in §1060.240 is narrowly limited to those 

things that qualify for consideration under design-based 

certification. 

EMA commented on §1060.250(b) that the requirement 

to retain data from routine emission tests for one year 

while retaining all other related test information for eight 

years is not appropriate. EMA commented that if 

records are required for eight years, all of the related 

information should be retained for the same time period. 

Information that is not related to the prescribed testing 

requirement should not be required to be retained 

If manufacturers are unable to manage recordkeeping 

according to multiple schedules, they should keep all 

their records for eight years. We believe this is not 

sufficient justification to require all manufacturers to 

keep routine testing records for eight years. We have 

revised the regulation to clarify the recordkeeping 

requirements related to routine testing information. 

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Nonroad Spark-Ignition Engines—Summary and Analysis of Comments 

because it is not required to be recorded initially. 

EMA commented on §1060.401 that EPA should clarify This is not correct. EPA will generally use the fuel 

for any in-use testing that may be performed that they specified in the regulation for any particular test. If 

will use the same test procedure and fuel as that manufacturers use an approved alternate fuel, we may 

specified by the manufacturer at the time of certification. optionally test with the specified test fuel or the alternate 

fuel. 

Letters: 

Commenter Document # 

OPEI 0675 

Massachusetts Marine Trade Association 0634 

EMA 0691 

Honda 0705 

NMMA 0688 

Mercury Marine 0693 

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