STAFF REPORT 

INITIAL STATEMENT OF REASONS FOR PROPOSED RULEMAKING 

PUBLIC HEARING TO CONSIDER AMENDMENTS TO THE CURRENT 

REGULATIONS FOR LARGE SPARK-IGNITION ENGINES WITH AN ENGINE 

DISPLACEMENT LESS THAN OR EQUAL TO ONE LITER 

Date of Release: October 3, 2008 

Scheduled for Consideration: November 20, 2008 

Location: 

Air Resources Board 

Byron Sher Auditorium 

1001 “I” Street 

Sacramento, CA 95814 

This report has been reviewed by the staff of the California Air Resources Board and 

approved for publication. Approval does not signify that the contents necessarily reflect 

the views and policies of the Air Resources Board, nor does mention of trade names or 

commercial products constitute endorsement or recommendation for use. 
1 

TABLE OF CONTENTS 

EXECUTIVE SUMMARY ..............................................................................................................................2

1. INTRODUCTION..................................................................................................................................4

2. BACKGROUND ...................................................................................................................................4

2.1 LEGAL AUTHORITY .........................................................................................................................4

2.2 REGULATORY HISTORY ..................................................................................................................5

2.3 EMISSIONS INVENTORY...................................................................................................................6

2.4 RELATED FEDERAL REGULATIONS ..................................................................................................7

2.5 PUBLIC PROCESS...........................................................................................................................8

3. DISCUSSION .......................................................................................................................................9

3.1 EXHAUST EMISSION STANDARDS ....................................................................................................9

3.1.1 Overview................................................................................................................................10

3.1.2 Engines ≤ 825 cc...................................................................................................................11

3.1.3 Engines > 825 cc - ≤ 1.0 L.....................................................................................................11

3.2 EVAPORATIVE EMISSION REQUIREMENTS......................................................................................14

3.3 OFF-HIGHWAY RECREATIONAL VEHICLES......................................................................................15

4. ENVIRONMENTAL AND ECONOMIC IMPACTS .............................................................................16

4.1 ENVIRONMENTAL IMPACT..............................................................................................................16

4.1.1 Emission Reductions.............................................................................................................16

4.1.2 Environmental Justice ...........................................................................................................16

4.2 COST AND COST-EFFECTIVENESS.................................................................................................17

4.2.1 Near-Term (2011) Emission Standards ................................................................................17

4.2.2 Long-Term (2015) Emission Standards ................................................................................20

4.3 ECONOMIC IMPACT ON THE ECONOMY OF THE STATE.....................................................................22

4.3.1 Legal Requirement ................................................................................................................23

4.3.2 Businesses Affected..............................................................................................................23

4.3.3 Impact on Small Businesses .................................................................................................24

4.3.4 Potential Impact on Distributors and Dealers........................................................................24

4.3.5 Potential Impact on Business Competitiveness ....................................................................25

4.3.6 Potential Impact on Employment...........................................................................................25

5. ALTERNATIVES CONSIDERED.......................................................................................................25

5.1 TAKE NO ACTION .........................................................................................................................25

5.2 ADOPT MORE STRINGENT LSI ENGINE EMISSION STANDARDS .......................................................26

5.3 ADOPT THE U.S. EPA’S EMISSION STANDARDS FOR LSI ENGINES ≤ 1.0 L......................................26

5.4 ADOPT EMA’S PROPOSAL............................................................................................................26

5.5 SUMMARY OF ALTERNATIVES EVALUATED .....................................................................................27

6. CONCLUSIONS AND RECOMMENDATIONS .................................................................................27

7. REFERENCES...................................................................................................................................28

APPENDIX A: Proposed Amendments to the Large Spark-Ignition Engines Exhaust Emission Regulation 

APPENDIX B: Proposed Amendments to the California Exhaust and Evaporative Emission Standards 

and Test Procedures for New 2010 and Later Off-Road Large Spark-Ignition Engines 
2 

EXECUTIVE SUMMARY 

To address California’s acute air quality problems, the federal Clean Air Act granted 

California the unique authority to adopt and enforce rules to control mobile source 

emissions within California. The California Clean Air Act requires the Air Resources 

Board (ARB or Board) to achieve the maximum degree of emission reductions possible 

from vehicular and other mobile sources in order to attain the State ambient air quality 

standards by the earliest practicable date. 

The large spark-ignition (LSI) engine category is defined as off-road spark-ignition 

engines greater than 19 kilowatts. New LSI engines with an engine displacement less 

than or equal to one liter (≤ 1.0 L) are typically used in such applications as portable 

generators, large turf care equipment, and industrial equipment. The Board initially 

adopted exhaust emission standards for these engines in 1998. The existing 

regulations for LSI engines ≤ 1.0 L include exhaust emission standards, emissions test 

procedures, and provisions for warranty and production compliance programs 

(California Code of Regulations, Title 13, Chapter 9, Sections 2430 through 2439). The 

regulations were first implemented in 2002. 

In May of 2006, the Board approved more stringent regulations for LSI engines with an 

engine displacement greater than one liter. LSI engines ≤ 1.0 L were not addressed in 

that regulation. In recent years, the population of LSI engines ≤ 1.0 L, the number of 

engine families, and the maximum power ratings of these engines have grown 

significantly, making emissions from these engines a greater concern. To address this 

concern, staff’s proposal would amend the existing California exhaust emission 

regulations for new LSI engines ≤ 1.0 L to include more stringent exhaust emission 

standards and, for the first time, evaporative emissions requirements. The proposed 

exhaust emissions standards are presented in the following table. 

Current and Proposed Exhaust Emissions Standards for LSI Engines ≤ 1.0 L 

Model Year Engine Displacement HC+NOx 

(g/kW-hr) 

CO 

(g/kW-hr) 

Current 

2002 - 2010 ≤ 1.0 L 12.0 549 

2011 and 

subsequent ≤ 825 cc* 8.0 549 

2011 - 2014 > 825 cc* - ≤ 1.0 L 6.5 375 

2015 and 

subsequent > 825 cc* - ≤ 1.0 L 0.8 20.6 

* cc: cubic centimeters 
3 

The major proposed amendments include the following: 

• More stringent exhaust emission standards, 

• Evaporative emission standards and requirements, 

• Off-highway recreational vehicles (OHRV) test procedures for LSI engines used 

in OHRV-like applications. 

Staff’s proposal would reduce hydrocarbons plus oxides of nitrogen (HC+NOx) by 

4.5 tons per day in 2020, at an estimated cost of $0.01 - $7.16 per pound. 

Staff held two public workshops to allow for continuing public involvement and input 

throughout the development of the proposed regulations. In addition, staff considered 

alternatives to the proposal, including taking no action, setting more stringent standards, 

adopting the United States Environmental Protection Agency emission standards, and 

adopting an Engine Manufacturers Association proposal. Staff has determined that 

adopting its current proposal is both technologically feasible and cost-effective. 
4 

PUBLIC HEARING TO CONSIDER AMENDMENTS TO THE CURRENT 

REGULATIONS FOR LARGE SPARK-IGNITION ENGINES WITH AN ENGINE 

DISPLACEMENT LESS THAN OR EQUAL TO ONE LITER

1. INTRODUCTION 

Off-road large spark-ignition (LSI) engines run on gasoline or an alternative fuel such as 

liquefied petroleum gas (LPG) or compressed natural gas (CNG), and are rated above 

19 kilowatts (kW). Typical applications for off-road LSI engines include forklifts, portable 

generators, large turf care equipment, irrigation pumps, welders, air compressors, 

scrubber/sweepers, airport ground support equipment, and a wide array of other 

agricultural, construction, and general industrial equipment. Exhaust and evaporative 

emissions from LSI engines and equipment are a significant source of hydrocarbon 

(HC) and oxides of nitrogen (NOx) emissions in California. 

This report presents staff’s proposal for amending the current LSI engine regulations to 

include more stringent exhaust and evaporative emission requirements for LSI engines 

less than or equal to one liter (≤ 1.0 L) in displacement. Compliance with the proposed 

emission standards will substantially reduce HC and NOx emissions from new 2011 and 

later engines. 

This report addresses the need for the proposed regulatory changes, provides a 

summary of the proposed changes, presents the environmental and economic impacts 

of the proposal, and discusses alternatives to staff’s proposal. Appendix A contains the 

proposed amendments to the current regulation, and Appendix B contains the proposed 

amendments to the test procedures. 

2. BACKGROUND 

2.1 Legal Authority 

In 1988, the Legislature enacted the California Clean Air Act, which declared that 

attainment of state ambient air quality standards is necessary to promote and protect 

public health, particularly the health of children, older people, and those with respiratory 

diseases. The Legislature also directed that these standards be attained by the earliest 

practicable date. 

Health and Safety Code sections 43013 and 43018 direct ARB to achieve the maximum 

feasible and cost-effective emission reductions from all off-road mobile source 

categories. 
5 

2.2 Regulatory History 

The Board first approved regulations for LSI engines and equipment in 1998. The 

regulations include exhaust emission standards and test procedures, labeling 

requirements, warranty, in-use compliance testing, production line testing, and fleet 

requirements (California Code of Regulations (CCR), Title 13, Chapter 9, Sections 2430 

through 2439). 

The LSI engine category is divided based on engine displacement. For LSI engines 

larger than one liter (> 1.0 L) in displacement, emission control requirements were 

implemented beginning with the 2001 model year (MY). This engine size category is 

almost exclusively made up of automotive-derived engines which are readily adapted to 

use existing automotive emission controls. The smaller displacement engines, LSI 

engines ≤ 1.0 L, are typically used in such applications as portable generators 

(approximately 40 percent), large turf care equipment (approximately 30 percent), and 

industrial equipment (approximately 30 percent). At the time of the initial rulemaking for 

LSI engines in 1998, industry argued that the LSI engines ≤ 1.0 L were more similar to 

small off-road engines (SORE) than to the LSI engines > 1.0 L and therefore it would be 

more appropriate that they be required to meet the SORE emission standards. The 

Board agreed and approved emission standards equivalent to those for SORE engines 

greater than or equal to 225 cubic centimeters (SORE ≥ 225 cc). Thus, beginning with 

the 2002 MY (see Table 2.1, below), LSI engines ≤ 1.0 L were subject to a 12.0 grams 

per kilowatt-hour (g/kW-hr) HC+NOx standard and a 549 g/kW-hr carbon monoxide 

(CO) standard. In 2003, the Board approved an 8.0 g/kW-hr HC+NOx standard for 

SORE ≥ 225 cc for 2008 MY and later. Staff did not propose to tighter the smaller LSI 

engine exhaust emission standards at that time. 

Table 2.1 

 Exhaust Emission Standards 

For SORE ≥ 225 cc and LSI Engines ≤ 1.0L 

Model Year Engine Category HC+NOx 

(g/kW-hr) 

CO 

(g/kW-hr) 

SORE ≥ 225 cc 12.0 549 

2002 

LSI ≤ 1.0 L 12.0 549 

SORE ≥ 225 cc 8.0 549 

2008 

LSI ≤ 1.0 L 12.0 549 
6 

In May 2006, the Board approved new regulations for LSI engines > 1.0 L. As shown in 

Table 2.2, for the 2007 through 2009 MY, these engines are required to meet emission 

standards of 2.7 g/kW-hr HC+NOx and 4.4 g/kW-hr CO. For 2010 and subsequent MY, 

the HC+NOx emission standard drops to 0.8 g/kW-hr. Note that the CO emission 

standard was relaxed to allow for the “trade-off” of significantly more HC+NOx benefits. 

Like the 2003 rulemaking, this rulemaking did not include revisions to the emission 

standards for LSI engines ≤ 1.0 L. 

Table 2.2 

Exhaust Emissions Standards for LSI Engines > 1.0 L 

Model Year HC+NOx 

(g/kW-hr) 

CO 

(g/kW-hr) 

2007 - 2009 2.7 4.4 

2010 and subsequent 0.8 20.6 

2.3 Emissions Inventory 

Figures 2.1 and 2.2 illustrate the total statewide population and HC+NOx emissions 

inventory, respectively, for LSI engines ≤ 1.0 L in 2000, 2010, and 2020. Since the 

implementation of exhaust emission standards for these engines, their engine-out 

emission levels have decreased substantially. However, as a result of population 

growth between 2010 and 2020, the emissions contribution from these engines is 

expected to rise. 

Figure 2.1 

LSI Engines ≤ 1.0 L 

Statewide Population Estimates 

0

50,000

100,000

150,000

200,000

2000 2010 2020
7 

Figure 2.2 

LSI Engines ≤ 1.0 L 

Statewide HC+NOx Emissions 

Exhaust

Evap

Exhaust

Evap

Exhaust

Evap

0

2

4

6

8

10

12

14

Tons Per Day

2000 2010 2020

2.4 Related Federal Regulations 

Large spark-ignition engines are regulated federally under Title 40 of the Code of 

Federal Regulations (CFR), part 1048, which generally harmonizes with the California 

emission standards until 2010, when more stringent California standards go into effect 

for LSI engines > 1.0 L. The federal LSI engine regulations allow manufacturers to 

certify LSI engines ≤ 1.0 L that are between 19 kW and 30 kW to the nonroad sparkignition engines (i.e., SORE) requirements of 40 CFR Part 90 or 1054. 

On September 4, 2008, the United States Environmental Protection Agency (U.S. EPA) 

finalized its phase 3 HC+NOx emission standard of 8.0 g/kW-hr for the SORE ≥ 225 cc 

and LSI engines ≤ 1.0 L starting in the 2011 MY, as shown in Table 2.3 (U.S. EPA 

2008). Both the phase 2 and phase 3 U.S. EPA standards are less stringent than staff’s 

proposed exhaust emissions standards for LSI engines ≤ 1.0 L. 

Table 2.3 

U.S. EPA Exhaust Emissions Standards for LSI Engines ≤ 1.0 L 

(also apply to SORE ≥ 225 cc) 

Model Year HC+NOx 

(g/kW-hr) 

CO 

(g/kW-hr) 

Phase 2 

2005 - 2010 12.1 610 

Phase 3 

2011 and subsequent 8.0 610 
8 

2.5 Public Process 

Staff met with interested stakeholders and solicited input numerous times during the 

development of this proposal. Staff conducted public workshops on November 14, 2007 

and April 21, 2008 to aid in developing the proposed regulations. Workshop notices 

were sent out via email on the msprog listserve list and orspark listserve list to all 

stakeholders, including environmental organizations, engine manufacturers, equipment 

manufacturers, and trade associations, as well as other interested parties. At the 

workshops and subsequently, staff shared draft proposed regulatory language. Public 

information concerning the development of this proposal was also made available on 

ARB's website at www.arb.ca.gov/msprog/offroad/orspark/orspark.htm. 

Staff met with many of the engine and equipment manufacturers to discuss individual 

concerns. Staff also sent an extensive survey to LSI engine and equipment 

manufacturers to help evaluate the level of technology currently utilized by industry as 

well as examine specific issues including equipment cost, engine durability, and market 

trends. Staff received replies from 14 manufacturers (including some who have 

indicated they do not intend to participate in the LSI engine ≤ 1.0 L market), 

representing approximately 70 percent of the market. A listing of stakeholder meetings, 

along with meeting dates, is shown below in Table 2.4. 

Table 2.4 

Stakeholder Meetings and Survey Responses 

Stakeholder Date(s) 

Briggs & Stratton Corp. 2/8/08, 4/3/08, 8/12/08, 8/14/08 

China Motor Company 3/14/08* 

Daihatsu Motor Company, LTD 3/14/08* 

Engine Manufacturers Association 2/8/08, 4/24/08, 6/24/08, 8/12/08 

Generac Power Systems, Inc. 3/14/08* 

John Deere 8/12/08 

Kawasaki Heavy Industries, LTD 2/8/08, 8/12/08 

Kohler Company 2/7/08, 2/8/08, 4/21/08, 4/24/08, 8/12/08 

Kubota Corp. 3/16/08* 

MECA 11/29/07, 5/16/08 

Nissan Motor Co., Ltd. 2/27/08* 

Outdoor Power Equipment Institute 2/8/08, 4/24/08, 5/6/08, 8/12/08 

Polaris Industries Inc. 2/19/08, 4/8/08, 7/8/08 

The Toro Company 2/8/08, 4/24/08, 8/12/08 

Toyota Industrial Equipment Mfg. Inc. 2/27/08* 

Vantage Power Vehicle, Inc. 3/5/08, 3/20/08 

Wisconsin Motors 2/25/08* 

Zenith Power Products, LLC 3/5/08* 

* Survey only 
9 

As a result of the oral and written comments received, staff made significant changes to 

the proposed regulations and test procedures, which are reflected in the staff’s 

proposal. 

3. DISCUSSION 

3.1 Exhaust Emission Standards 

As shown in Figure 3.1, the current standards for LSI engines ≤ 1.0 L (2nd bar) are 

significantly less stringent than those for LSI engines > 1.0 L, and in fact are even 

less stringent than ARB’s recently implemented tier 3 emission standards for 

SORE ≥ 225 cc. In addition, the growing population and power ratings within this 

category also concern staff. As shown previously in Figure 2.1, and shown below in 

Figure 3.2, the population and number of engine families of the LSI engines ≤ 1.0 L 

have grown significantly since 2002, when emission standards first went into effect. 

Figure 3.1 

Adopted HC+NOx Emission Standards 

for SORE ≥ 225 cc and LSI Engines 

8

12

2.7

0.8

0

2

4

6

8

10

12

HC+NOx, g/kW-hr

SORE ≥ 225cc

2008 & later

LSI engines ≤ 1.0 L

2002 & later

LSI engines > 1.0 L

2007-2009

LSI engines > 1.0 L

2010 & later
10 

Figure 3.2 

Number of Certified LSI Engine Families 

0

10

20

30

40

50

60

70

No. of Engine Families

2002 2003 2004 2005 2006 2007 2008

Model Year

LSI > 1.0 L

LSI ≤ 1.0 L

3.1.1 Overview 

To evaluate the industry’s ability to meet more stringent standards, staff examined data 

from a variety of sources1

, including the most recent certification emission data 

submitted by manufacturers. As shown below in Table 3.1, the HC+NOx emission 

levels for gasoline powered LSI engines ≤ 1.0 L without catalysts are in the range of 5.1 

to 11.2 g/kW-hr (standard is 12.0 g/kW-hr). However, catalyst-equipped engines within 

the category display emission levels as low as 0.5 g/kW-hr HC+NOx. This 

demonstrates the technical feasibility of achieving significantly lower HC+NOx emissions 

utilizing currently available emission control technologies. 

Table 3.1 

HC+NOx Emissions Levels of 2008 MY Certified LSI Engines ≤ 1.0 L (g/kW-hr) 

2008 MY 

Certification Data 

Gasoline Fueled LSI 

Engines ≤ 1.0 L without 

Catalyst 

All LSI 

Engines ≤ 1.0 L 

 Max 11.2 11.2 

HC+NOx Avg 7.9 6.6 

 Min 5.1 0.5 

 

(1) Southwest Research Institute (1999), Southwest Research Institute (2004), U.S. EPA (2007), and 

MECA (2008). 
11 

Based on a review of the available data and an assessment of available technology, 

staff proposes the emissions standards summarized in Table 3.2 below. In addition to 

the more stringent emission standards, staff is proposing a new engine displacement 

cutpoint at 825 cc, as explained in further detail below. 

Table 3.2 

Current and Proposed Emission Standards for LSI Engines ≤ 1.0 L 

 Model Year Engine 

Displacement 

HC+NOx 

(g/kW-hr) 

CO 

(g/kW-hr) 

Current 2002 and 

subsequent ≤ 1.0 L 12.0 549 

2011 and 

subsequent ≤ 825 cc 8.0 549 

Proposed 2011 - 2014 > 825 cc - ≤ 1.0 L 6.5 375 

2015 and 

subsequent > 825 cc - ≤ 1.0 L 0.8 20.6 

3.1.2 Engines ≤ 825 cc 

There are currently no engine families certified with displacements between 775 cc and 

850 cc. During development of staff’s proposal, EMA suggested that engines below 

825 cc should be treated separately from those between 825 cc and 1.0 L. Although 

the engines below 825 cc do not currently differ in technology from engines between 

825 cc and 1.0 L, they do tend to be used in much less expensive equipment, which 

would be less able to absorb increased costs of more advanced technologies like an 

electronic fuel injection system. Thus, staff proposes that these engines meet emission 

standards equivalent to the tier 3 emission standards for SORE ≥ 225 cc. Most of these 

smaller LSI engines are designed for turf care equipment, and their performance and 

operation characteristics are comparable to those of SORE ≥ 225 cc. Currently, three 

out of four certified 2008 MY LSI engine families in this range can meet the proposed 

emission standards, demonstrating both the technical and the economic feasibility of the 

proposal. 

3.1.3 Engines > 825 cc - ≤ 1.0 L 

Engines greater than 825 cc are a larger concern. Currently, 86 percent of the certified 

2008 MY LSI engine families ≤ 1.0 L have engine displacements greater than 825 cc. 

As shown in Figure 3.3, this is an increase of 11 engine families compared to the 2003 

MY. 
12 

Figure 3.3 

Comparison of the Number of Certified LSI Engine Families

in 2003 MY and 2008 MY

0

5

10

15

20

25

30

35

45050055060065070075080085090095010001050110011501200125013001350140014501500155016001650170017501800185019001950> 2000

Engine Displacement (cc)

No. of Engine Families

2003 2008

The projected sales of LSI engines ≤ 1.0 L are approaching 50 percent of the total LSI 

engines sales, up from the 15 percent estimated in 2002. Simultaneously, the number 

of engine families offered with displacements between 1.0 L and 1.6 L has declined to 

zero. This suggests that there is a migration from the more stringently regulated LSI 

engines > 1.0 L category to the significantly more lenient LSI engines ≤ 1.0 L category. 

Staff’s proposal would result in the same emission standard for LSI engines > 825 cc, in 

a two-step process. 

3.1.3.1 Near-Term (2011) Emission Standards 

As shown previously in Table 3.2, staff proposes a 6.5 g/kW-hr HC+NOx emission 

standard to be implemented in 2011. During development of the 1998 LSI engine 

rulemaking, staff had originally considered a 6.5 g/kW-hr HC+NOx emission standard, 

based on testing performed by the Southwest Research Institute (SwRI, 1999). But, as 

mentioned previously, industry argued that the engines had more similarities to SORE 

than to the larger LSI engines and therefore it would be more appropriate that they meet 

the less-stringent SORE standard. Currently, however, with the increase in engine size 

and power ratings, staff believes 6.5 g/kW-hr HC+NOx and 375 g/kW-hr CO are 

appropriate near-term emission standards. These proposed emission standards are 
13 

already being met, as shown below in Table 3.3. Thirty-seven percent of the 2008 MY 

LSI engine families ≤ 1.0 L were certified with emissions of 6.5 g/kW-hr HC+NOx or less, 

representing 48 percent of the projected California sales. 

Table 3.3 

Engine Families Certified in 2008 Model Year 

Meeting the Proposed Near-Term HC+NOx Emission Standard 

Scenario HC+NOx

(g/kW-hr)

Engine 

Families 

No. of 

Manufacturers

Projected 

Sales 

Proposed > 825 cc - ≤ 1.0 L 

2011 – 2014 standard 6.5 37% (9 out of 24) 8 48% (4,000) 

3.1.3.2 Long-Term (2015) Emission Standards 

For the longer term, beginning with the 2015 MY, staff proposes to harmonize the 

emission standards for LSI engines between 825 cc and 1.0 L with the existing emission 

standards for LSI engines > 1.0 L (0.8 g/kW-hr HC+NOx, 20.6 g/kW-hr CO). As shown 

in Table 3.4, three engine families are already certified at the proposed long-term 

HC+NOx emission standard. 

Table 3.4 

Engine Families Certified in 2008 Model Year 

Meeting Proposed Long-Term HC+NOx Emission Standard 

Scenario HC+NOx

(g/kW-hr)

Engine 

Families 

No. of 

Manufacturers

Projected 

Sales 

Proposed > 825 cc - ≤ 1.0 L 

2015 and later standard 0.8 12% (3 out of 24) 3 6% (500) 

Some manufacturers have expressed concerns primarily over the economic impact of 

staff’s proposal, citing that these three engine families represent only a small segment 

of the market, and that the engines are primarily used in vehicular applications, such as 

utility vehicles. Manufacturers have also indicated that the proposed emission 

standards would require liquid-cooling, closed-loop electronic fuel injection systems, 

and three-way catalysts. 

Staff agrees with industry with regard to the technology most likely needed to comply 

with the proposed emission standards. However, although many engines in the 

category are air-cooled currently, almost every manufacturer has experience with liquid 
14 

cooling2. The 2008 MY certification applications show that 15 of the 24 engine families 

above 825 cc are liquid-cooled. Although some manufacturers have expressed concern 

that liquid-cooled engines might not be accepted in the market, liquid-cooled engines 

offer several advantages, primarily because they are capable of running cooler than aircooled engines. With adequate cooling, a manufacturer can usually increase the 

horsepower of a given engine without increasing its size3. This trend of achieving more 

horsepower without increasing engine size is a common marketing tool and design goal 

of manufacturers. In addition, liquid-cooled engines run more fuel efficiently reducing 

production of carbon dioxide, a greenhouse gas. 

Closed-loop electronic fuel injection and catalysts, although not as common in this 

category, are also well understood technologies commonly used on LSI engines > 1.0 L. 

Of the 24 engine families between 825 cc and 1.0 L that are certified for the 2008 MY, 

four of them have a three-way catalyst and closed-loop electronic fuel injection system. 

While staff acknowledges industry’s concerns, the feasibility of the proposed standards 

is technically sound. With regard to the potential economic impact, the proposed 

emission standards are also cost-effective, as discussed in greater detail later in this 

report. Furthermore, the proposed 2015 implementation would allow seven years of 

lead time for manufacturers who do not yet meet the proposed standards to develop the 

requisite technology to be compatible with their engine designs and products. 

3.2 Evaporative Emission Requirements 

As shown previously in Figure 2.2, equipment with LSI engines ≤ 1.0 L contribute 

1.3 tons per day of evaporative HC emissions statewide in 2000. If left uncontrolled, the 

emissions will increase to 2.6 tons per day in 2020, due to population growth. 

To control the evaporative emissions, staff proposes that 2011 and later MY equipment 

with LSI engines ≤ 1.0 L meet the same evaporative emission requirements as 

SORE ≥ 225 cc equipment, as shown below in Table 3.5. However, while the 

evaporative requirements for SORE equipment allow for a small volume exemption for 

fuel tanks produced in less than 400 units, staff’s proposal for the LSI engines ≤ 1.0 L 

does not allow for this exemption. This is because there are several cost-effective 

solutions available that enable manufacturers to produce low-cost compliant fuel tanks4

. 

 

(2) Only one manufacturer of currently-certified LSI engines does not offer at least one liquid-cooled 

engine family in the SORE or LSI engine categories.

(3) For a given displacement engine, increasing horsepower is usually accomplished by modifying a 

variety of engine parameters (e.g., increased compression ratio, higher engine speeds). Because these

modifications cause the engine to “work harder”, more heat is generated. 

(4) The cost of complying fuel tanks are also more easily absorbed for LSI engines and equipment than

for SORE because of the higher base prices of LSI engines and equipment. 
15 

Table 3.5 

Proposed Evaporative Emissions 

Performance and Design Standards 

Requirements 2011 2012 2013+ 

Performance 

Requirements 

Diurnal Standard 

g HC/day 1.20 + 0.056 × tank vol.(L)

Fuel Hose Permeation 

g ROG*/m2/day 15

Fuel Tank Permeation 

g ROG/m2/day Design 2.5 1.5

Requirements 

Carbon Canister or 

Equivalent Butane Working 

Capacity, g HC 

1.4 g/L (tanks ≥ 3.78 L) or 

1.0 g/L (tanks < 3.78 L) 

*ROG: Reactive Organic Gases5

3.3 Off-Highway Recreational Vehicles 

Some LSI engines ≤ 1.0 L are used in vehicles that meet all the requirements of the 

“Off-Road Sport Vehicle,” or “Off-Road Utility Vehicle” definitions in CCR, Title 13, 

Section 2411(a) (13),(17), or (18), with the exception of payload capacity. The current 

definitions of off-road sport vehicles and off-road utility vehicles include a maximum limit 

on rear payload capacity. This limit was established to ensure that the vehicles were 

truly designed and used for recreational purposes, rather than for industrial or 

commercial purposes. Staff now believes that this limit is inappropriate given that the 

current trend for recreational vehicles is to significantly increase payload, beyond the 

limits of the existing regulations. 

Staff proposes that most LSI engines used in vehicles similar to off-highway recreational 

vehicles be subject to the proposed near-term 2011 emission standards, but be allowed 

to use the off-highway recreational vehicle test procedures and certification procedures. 

This would simplify the certification process and provide flexible testing options as the 

chassis-based testing becomes a federal requirement for off-highway recreational 

vehicles in 2014. These engines form a subset of LSI engines ≤ 1.0 L that would most 

appropriately be regulated in the off-highway recreational vehicle category. Therefore, 

this proposal would exclude these engines from the proposed 2015 standards; staff’s 

long-term goal is to amend the current off-highway recreational vehicle regulations to 

incorporate this type of engine. 

 

(5) Reactive organic gases (ROG) are a subset of hydrocarbons (HC) that excludes methane and other 

photochemically non-reactive hydrocarbons that do not contribute to the formation of ozone. The exhaust 

emission standards are usually established for HC, but the permeation standards and emission modeling 

for ozone impact use ROG. 
16 

4. ENVIRONMENTAL AND ECONOMIC IMPACTS 

4.1 Environmental Impact 

4.1.1 Emission Reductions 

Table 4.1 shows the statewide emissions benefit of the staff’s proposal in 2014 and 

2020. In 2014, the statewide ROG+NOx emissions would be reduced by 1.9 tons per 

day. In 2020, the proposal would reduce approximately 4.5 tons per day of ROG+NOx. 

Table 4.1 

Estimated Benefit of the Proposal, Statewide Annual Average 

ROG+NOx Emission Reductions 

(tons per day) Staff Proposal Element 

2014 MY 2020 MY 

Exhaust emission standards 1.7 4.1 

Evaporative emission requirements 0.2 0.4 

Total 1.9* 4.5* 

* Benefits have been rounded to the nearest tenth. 

4.1.2 Environmental Justice 

State law defines environmental justice as the fair treatment of people of all races, 

cultures, and incomes with respect to the development, adoption, implementation, and 

enforcement of environmental laws, regulations, and policies (Senate Bill 115, Solis; 

Stats 1999, Ch. 690; Government Code § 65040.12(c)). The Board has established a 

framework for incorporating environmental justice into the ARB's programs consistent 

with the directives of State law. The policies developed apply to all communities in 

California, but recognize that environmental justice issues have been raised more in the 

context of low income and minority communities, which sometimes experience higher 

exposures to some pollutants as a result of the cumulative impacts of air pollution from 

multiple mobile, commercial, industrial, area wide, and other sources. Over the past 

twenty-five years, the ARB, local air districts, and federal air pollution control programs 

have made substantial progress towards improving the air quality in California. 

However, some communities continue to experience higher exposures than others as a 

result of the cumulative impacts of air pollution from multiple mobile and stationary 

sources and thus may suffer a disproportionate level of adverse health effects. Since 

the same ambient air quality standards apply to all regions of the State, all communities, 

including environmental justice communities, will benefit from the air quality benefits 

associated with the proposal. Alternatives to the proposed recommendations, such as 

recommending no change to the current program could adversely affect all 
17 

communities. As additional relevant scientific evidence becomes available, the LSI 

engine emission standards will be reviewed again to make certain that the health of the 

public is protected with an adequate margin of safety. 

To ensure that everyone has an opportunity to stay informed and participate fully in the 

development of the proposal, staff has held workshops in El Monte and has distributed 

information through the internet, as described in section 2.5. 

4.2 Cost and Cost-Effectiveness 

To determine the economic impact of the proposed regulations, staff evaluated cost 

information supplied by engine and equipment manufacturers, the Outdoor Power 

Equipment Institute, Inc., Engine Manufacturers Association, Manufacturers of Emission 

Controls Association, and U.S. EPA. 

4.2.1 Near-Term (2011) Emission Standards 

4.2.1.1 Engine Development Costs 

Based on responses to a survey sent to manufacturers, the proposed exhaust and 

evaporative emission standards would require minimal lead time and would impose 

relatively minor engine and equipment development costs, as shown in Table 4.2. The 

wide range of development costs reflect the situation where in some cases, there would 

be no need for additional engine development since the engine family already meets the 

proposed emission standards. In fact, 48 percent of the 2008 MY engine families 

already meet the proposed standards, as noted in Section 3.1.3.1. 

Table 4.2 

Estimated Engine and Equipment Development Costs 

to Meet the 2011 Emission Standards 

Item Cost 

Research, engine development, tooling, and 

equipment redesign cost per engine family $0 - 100,000

Weighted average cost per engine* $8.14

Source: LSI engine and equipment manufacturers survey results, April 2008. 

* Weighted average cost per engine assumes 4 years of production meet the standards. 

4.2.1.2 Emission Controls Costs 

The 2011 exhaust emission standards should not require any additional emission 

control components. Engine modifications and air/fuel ratio calibration changes should 

be sufficient to bring the engines that do not meet the standards into compliance. 
18 

However, meeting the evaporative standards could require modifications to fuel tanks, 

fuel hoses, and fuel caps, as well as the addition of a carbon canister. Since the 

evaporative standards and procedures are equivalent to those for SORE ≥ 225 cc, staff 

has assumed costs identical to those noted in the 2003 SORE staff report. As shown in 

Table 4.3, the estimated emission controls cost for manufacturers of LSI engines ≤ 1.0 L 

would be in the range of $16.21 - $70.21 per unit. 

Table 4.3 

Estimated Emission Controls Cost 

to Meet the 2011 Emission Standards 

Item Cost Range 

($/engine) 

Tank Permeation $1.00-$27.00

Fuel Cap $1.00

Fuel hose Permeation $1.00 - $2.00

Venting Control (Carbon Canister) $10.00 - $37.00

Testing $3.21

Total $16.21 - $70.21

Source: SORE 2003 evaporative control cost estimates. 

Staff did not calculate a weighted average for the emission controls cost, since specific 

information is not available on whether a given currently certified engine family already 

is equipped with the necessary emissions controls (e.g., fuel tank permeation)6. Thus, it 

is unknown at this time whether all engines would require the addition of all the 

identified controls. However, to ensure that costs were not underestimated the worst 

case emission controls cost ($70.21) was used in all cost and cost-effectiveness 

calculations. Thus, the combined total engine costs would be approximately $78 per 

unit. 

4.2.1.3 Equipment Redesign Costs 

Industry did not provide specific cost-estimates for possible equipment redesign to 

accommodate the cleaner engines. However, the changes envisioned for the 2011 

standards should not require any major equipment redesign, as engine changes would 

 

(6) In general, information on a manufacturer’s intent to use specific emission controls is provided in the 

manufacturer’s application for certification. The emission controls discussed here are not required at this 

point. Thus, the information is not (yet) available because a manufacturer will not be required to note 

such information in its certification application until the proposed regulations are implemented. 
19 

be internal (e.g., calibration changes) and fuel system changes are primarily a matter of 

using improved components and the addition of a relatively small carbon canister. 

4.2.1.4 Comparison of Cost Increase to Equipment Cost 

The cost range for an LSI engine ≤ 1.0 L is $500 to $8,000, and equipment or vehicle 

costs range from $2,700 to $50,000 (covering both consumer products and professional 

products). A comparison of the estimated worst-case cost increase ($78) to the base 

price of equipment indicates that for extremely low-cost equipment, emission controls 

could approach three percent of the base cost. It should be recognized that many of 

these engines (both the smaller as well as the larger engines > 825 cc) meet the 

proposed exhaust standards already. 

4.2.1.5 Cost-Effectiveness 

To determine the cost-effectiveness of the near-term emission standards, staff divided 

the total cost by the ROG+NOx emission reductions expected over the average lifetime 

of the equipment. Separate values were calculated for the major categories of 

equipment that use LSI engines ≤ 1.0 L. As shown in Table 4.4, the resulting 

cost-effectiveness ranges from $0.01 to $0.15 per pound of ROG+NOx reduced. The 

2011 emission standards are very cost-effective when compared with recently adopted 

control measures. 

Table 4.4 

Lifetime Emission Reductions per Unit and Cost-Effectiveness 

For the 2011 Emission Standards 

Equipment Type 

ROG, 

Exh 

(lb) 

ROG, 

Evap 

(lb) 

NOx

(lb) 

ROG+NOx

(lb) 

Cost-Effectiveness 

(Cost per pound 

ROG+NOx reduced) 

Generator Sets 2,966 746 496 4,208 $0.02 

Lawn and Garden 

Tractors 277 338 63 678 $0.12 

Commercial Turf 

Equipment 184 317 45 546 $0.14 

Other Lawn and 

Garden Equipment 1,757 385 294 2,436 $0.03 

Sweepers/Scrubbers 4,813 148 746 5,707 $0.01 

Other General 

Industrial Equipment 285 173 63 521 $0.15 
20 

4.2.2 Long-Term (2015) Emission Standards 

4.2.2.1 Engine Development Costs 

Based on the responses to the survey sent to manufacturers, the proposed exhaust 

emission standards would require one to four years of lead time and would impose 

additional development costs, as shown in Table 4.5. The actual price increases for 

research and engine development are expected to be much lower than those estimated 

by the manufacturers, because the likely technologies to be used are the same as that 

used in the automotive industry for many years. Nevertheless, to be conservative, staff 

used the $840 figure shown in the table. 

Table 4.5 

Estimated Incremental Engine and Equipment Development Costs 

to Meet the 2015 Emission Standards 

Item Cost 

Research, engine development, and tooling cost per engine family $0 - $15,000,000

Weighted average cost per engine* $840

Source: LSI engine and equipment manufacturers survey results, April 2008. 

*Weighted average cost per engine assumes 4 years of production meet the standards. 

4.2.2.2 Emission Controls Costs 

Each engine manufacturer has its own strategy to meet the proposed emission 

standards. Some of them would convert air-cooled engines to liquid-cooled engines 

equipped with a three-way catalyst and closed-loop electronic fuel injection system, 

while some already use these technologies and can meet the proposed HC+NOx

standards without the need for additional emission controls. Unlike the 2011 emission 

standard analysis, staff was able to calculate a weighted average for the emission 

control costs. As shown in Table 4.6, the weighted average emission controls cost for 

manufacturers of LSI engines ≤ 1.0 L would be $400 per unit. The combined weighted 

average engine costs would thus be approximately $1,240 per unit. 
21 

Table 4.6 

Estimated Incremental Emission Controls Cost 

to Meet the 2015 Emission Standards 

Item Cost Range 

($/engine) 

Air-cooled to liquid-cooled (radiators, etc.) $0 - $200

Closed-loop Electronic Fuel Injection $0 - $600

Catalyst $0 - $150

Secondary air injection $0 - $15

Exhaust gas recirculation $0 - $40

Total $0 - $1005

Weighted average cost per engine $400

Source: LSI engine and equipment manufacturers’ survey results, April 2008 

4.2.2.3 Equipment Redesign Costs 

Industry did not provide specific cost-estimates for possible equipment redesign to 

accommodate the cleaner engines and exhaust aftertreatment systems. However, 

some products such as zero turn radius mowers are currently offered in both air-cooled 

and liquid-cooled configurations, at a dealer reported cost differential of approximately 

$700. Staff considers this to be a reasonable estimate for the cost of equipment 

redesign. The resulting weighted average cost increase to comply with the regulations 

would thus be $1,940 per unit. 

4.2.2.4 Comparison of Cost Increase to Equipment Cost 

A comparison of the weighted average cost increase ($1,940) to the base price of 

equipment ($2,700 to $50,000) indicates that for the least expensive equipment, 

emission controls could be more than seventy percent of the base cost. However, it 

should be recognized that the long lead-time allows a longer period for amortization of 

research and development costs, although only four years was used in staff’s 

calculations. Additionally, manufacturers would have the option to downsize the 

engines to displacements below 825 cc, which would subject them to more lenient and 

less costly emissions standards. Although some manufacturers have expressed the 

opinion that all engines in the category might be downsized to avoid the more stringent 

standards, staff believes that customer demand for greater power and the advantages 

offered by liquid-cooled and electronic controlled engines would prevent this from 

becoming an overall trend, particularly on equipment with a higher initial base cost. 
22 

4.2.2.5 Cost-Effectiveness 

To determine the cost-effectiveness of the 2015 emission standards, staff divided the 

weighted average cost increase by the incremental ROG+NOx lifetime emission 

reductions (i.e., above and beyond the near-term emission standard reductions). Again, 

separate values were calculated for the major categories of equipment that use LSI 

engines ≤ 1.0 L. As shown in Table 4.7, the resulting cost-effectiveness ranges from 

$0.52 to $7.16 per pound of ROG+NOx reduced. The 2015 emission standards are 

cost-effective when compared with recently adopted control measures. 

Table 4.7 

Lifetime Emission Reductions per Unit and Incremental Cost-Effectiveness 

For the 2015 Emission Standards 

Equipment Type 

ROG, 

Exh 

(lb) 

NOx

(lb) 

ROG+NOx

(lb) 

Cost-Effectiveness 

(Cost per pound 

ROG+NOx reduced) 

Generator Sets 1,636 968 2,604 $0.75 

Lawn and Garden 

Tractors 264 110 374 $5.19 

Commercial Turf 

Equipment 195 76 271 $7.16 

Other Lawn and 

Garden Equipment 967 573 1,540 $1.26 

Sweepers/Scrubbers 2,255 1,500 3,755 $0.52 

Other General 

Industrial Equipment 260 111 371 $5.23 

4.3 Economic Impact on the Economy of the State 

The proposed regulations are not expected to impose a significant cost burden to 

engine or equipment manufacturers. Staff anticipates manufacturers will pass on any 

added costs to consumers. 

Although a price increase for equipment with LSI engines ≤ 1.0 L may persuade a 

consumer to delay the purchase in the short-term, it is not expected to significantly 

impact the long-term demand because equipment eventually wears out and is replaced. 

Based on the above assumptions, staff expects the proposed regulations to impose no 

adverse impact on California competitiveness and employment. The following sections 

are intended to fulfill ARB’s legal requirements related to economic analysis and 

economic impact for stakeholders affected by these proposed regulations. 
23 

4.3.1 Legal Requirement 

Section 11346.3 of the Government Code requires State agencies to assess the 

potential for adverse economic impacts on California business enterprises and 

individuals when proposing to adopt or amend any administrative regulations. The 

assessment must include a consideration of the impact of the proposed regulations on 

California jobs, business expansion, elimination or creation, and the ability of California 

business to compete. 

Also, section 11346.5 of the Government Code requires State agencies to estimate the 

cost or savings to any state, local agency and school district in accordance with 

instructions adopted by the Department of Finance. The estimate must include any 

non-discretionary cost or savings to local agencies and the cost or savings in federal 

funding to the state. 

4.3.2 Businesses Affected 

Any business involved in the manufacturing of LSI engines ≤ 1.0 L and equipment will 

potentially be affected by the proposed regulations. Also potentially affected are 

businesses that supply engines and parts to these manufacturers, and those 

businesses that buy and sell equipment in California. The focus of the discussion 

below, however, will be on the engine and equipment manufacturers because these 

businesses would be directly affected by the proposed regulations. 

4.3.2.1 Engine Manufacturers 

There are currently 13 manufacturers of LSI engines ≤ 1.0 L that market certified 

engines in California, as shown in Table 4.8. Some of these manufacturers produce 

engines for off-road utility vehicle or off-road sport vehicle applications, which have 

been certified under the off-highway recreational vehicles regulations starting with the 

2008 MY. None of the manufacturers is located in California although some have small 

repair and distribution operations in California. 

Table 4.8 

Manufacturers with LSI Engines ≤ 1.0 L Certified in California 

BRIGGS & STRATTON CORPORATION POLARIS INDUSTRIES, INC. 

DAIHATSU MOTOR CO., LTD. TIGER TRUCK, LLC. 

GENERAC POWER SYSTEMS, INC. VANTAGE POWER VEHICLE, INC. 

KAWASAKI HEAVY INDUSTRIES, LTD. YAMAHA MOTOR CO., LTD. 

KOHLER COMPANY YANMAR DIESEL ENGINE CO., LTD. 

KUBOTA CORPORATION ZENITH POWER PRODUCTS, LLC 

MAG INTERNATIONAL 
24 

4.3.2.2 Equipment Manufacturers 

There are over 1,000 manufacturers of equipment with LSI engines ≤ 1.0 L nationwide. 

Many are “small” manufacturers that do not, however, meet the definition of a “Small 

Business” as defined in Government Code Section 11342.610. The majority of 

equipment is manufactured outside California. These manufacturers produce a wide 

variety of products. The affected equipment manufacturers fall into different industry 

classifications. A list of the industries that staff has been able to identify is provided in 

Table 4.9. 

Table 4.9 

Industries with Potentially Affected Manufacturers 

Standard Industrial 

Classification Code Industry 

3621 Motors and Generators 

3523 Farm Machinery and Equipment 

3524 Lawn and Garden Tractors/Equipment 

3531 Construction Machinery 

3561 Pumps and Pumping Equipment 

4.3.3 Impact on Small Businesses 

The proposed LSI engine regulations will have some impact, although not significant, on 

small businesses that buy and sell portable generators, large turf care equipment, and 

industrial equipment. For small retailers, during the initial years of implementation, the 

increased cost of equipment may lead to a slight drop in demand that could result in 

lower profits. The retailer would carry over unsold stock to the next year, possibly 

incurring less profit on the sale of these units. 

4.3.4 Potential Impact on Distributors and Dealers 

Most engine and equipment manufacturers sell their products through distributors and 

dealers, some of which are owned by manufacturers and some are independent. Most 

independently owned dealers are small businesses. Some low-volume manufacturers 

also deal directly with their customers. The distributors and dealers sell about 9,000 

pieces of equipment with LSI engines ≤ 1.0 L per year in California. This number is 

expected to grow substantially by 2020, as evidenced by the expected overall 

population growth (Figure 2.1). Although distributors and dealers are not directly 

affected by the proposed amendments, the amendments may affect them indirectly. If 

an increase in the price of engines and equipment reduces sales volume, dealers’ 

revenue would be affected adversely. 
25 

4.3.5 Potential Impact on Business Competitiveness 

The proposed amendments would have no significant impact on the ability of California 

engine and equipment manufacturers to compete with manufacturers of similar products 

in other states. This is because all manufacturers that produce these engines and 

equipment for sale in California are subject to the proposed amendments regardless of 

their location. Furthermore, all of the engine manufacturers, and most of the equipment 

manufacturers, are located outside of California. 

4.3.6 Potential Impact on Employment 

The proposed regulations are not expected to cause a noticeable reduction in California 

employment because California accounts for only a small share of manufacturing 

employment in off-road engine, equipment, and component production. However, some 

small businesses operating outside of California may leave the California market due to 

cost increases, which may result in a few jobs being eliminated. 

5. ALTERNATIVES CONSIDERED 

Staff evaluated four additional alternatives to the currently proposed regulations. These 

included: 

• Take no action 

• Adopt More Stringent LSI Engine Emission Standards

• Adopt the U.S. EPA’s Emission Standards for LSI Engines ≤ 1.0 L 

• Adopt EMA’s proposal 

These alternatives are discussed in detail below. 

5.1 Take No Action 

The first alternative evaluated was to take no action. Under this alternative, it is likely 

that few, if any, engine and equipment manufacturers would voluntarily incorporate 

additional emission control technology into their designs. The few manufacturers that 

did would be at a competitive disadvantage compared to manufacturers electing not to 

incorporate the emission control technology. Clearly, most of the exhaust and 

evaporative emission control technologies used in cars have not been adapted for use 

in LSI engines ≤ 1.0 L and equipment because manufacturers perceive the costs 

outweigh performance and fuel usage benefits. As the emission standards for LSI 

engines > 1.0 L, SORE, and off-road compression-ignition engines become more 

stringent, manufacturers would have greater incentive to market products that would fall 

into the LSI engines ≤ 1.0 L category. 

Therefore, this alternative would result in no emission reductions and would not 

contribute to the State Implementation Plan’s (SIP) control strategy to attain Federal 
26 

and State ambient air quality standards for ozone. The cost to the state is the potential 

loss of Federal highway funding, should an adequate SIP not be implemented. 

5.2 Adopt More Stringent LSI Engine Emission Standards 

Another alternative considered was to propose emission standards for LSI 

engines ≤ 1.0 L to be set at 0.8 g/kW-hr earlier than the 2015 date being proposed. As 

noted in section 3.1, there are three engine families that meet that level today 

establishing both technical feasibility and some ability for the market to support the 

costs of cleaner engines. The emission benefits for this alternative would exceed those 

from staff’s proposal. However, the earlier implementation would likely cause more 

disruption in the market, as manufacturers that do not currently offer liquid-cooled 

catalyst equipped engines would have less time to develop controls. Thus, this 

alternative was rejected in favor of a proposal which allows more time for development 

and cost recovery. 

5.3 Adopt the U.S. EPA’s Emission Standards for LSI Engines ≤ 1.0 L 

A third alternative would be to adopt the U.S. EPA’s emission standards for LSI 

engines ≤ 1.0 L. U.S. EPA’s phase 3 HC+NOx emission standard, starting in 2011 MY, 

is at the same level of stringency as the current SORE emission standard of 8.0 g/kWhr. The LSI engine industry supported this alternative. Although the U.S. EPA's 

emission standards were based on nationwide economic and environmental impacts as 

a whole, they do not adequately address the unique and compelling circumstances 

faced in California. The federal emissions standards ignore the technical capability of 

cleaner engines that are already available. There would be minimal emission benefit 

from this alternative and it would not contribute sufficiently to the SIP's control strategy 

to attain the Federal and State ambient air quality standards for ozone. The cost to the 

state is the potential loss of Federal highway funding, should an adequate SIP not be 

implemented. 

5.4 Adopt EMA’s Proposal 

In the development of this control measure, ARB staff has met with industry on 

numerous occasions to discuss emission standards and test procedures that would 

ensure emission reductions while addressing concerns raised by industry. Throughout 

this process, industry has raised several points, many of which have been integrated 

into staff’s proposal. In the June 24, 2008 meeting with EMA and manufacturer 

representatives, a proposal was brought forth to add two new classes of engines under 

the SORE category. A new class of SORE with an engine displacement between 225 

cc and 825 cc would have an HC+NOx exhaust emission standard of 8.0 g/kW-hr, which 

is same as the current SORE ≥ 225 cc emission standard, beginning in 2011. For the 

larger engines with an engine displacement > 825 cc and ≤ 1.0 L, EMA proposed an 

HC+NOx exhaust emission standard of 6.5 g/kW-hr, beginning in 2011, to be reduced to 

5.0 g/kW-hr in 2014. CO standard levels for both engine classes would remain equal to 

the CO standard for SORE ≥ 225 cc. 
27 

Staff did incorporate the majority of the proposal for LSI engines ≤ 825 cc. However, for 

the LSI engines > 825 cc and ≤ 1.0 L, the EMA proposal would provide less emission 

reductions (only 3.8 tons per day HC+NOx in 2020) and would not approach the 

emission levels being reached by some engines today. Similar to the alternative to 

adopt the U.S. EPA’s emission standards, the cost to the state is the potential loss of 

Federal highway funding, should an adequate SIP not be implemented. 

5.5 Summary of Alternatives Evaluated 

Each of the alternatives to the proposal falls short of staff’s proposal. The alternatives 

are either unnecessarily relaxed achieving little or no emission s benefit compared to 

staff’s proposal or are overly aggressive and likely to cause major market disruption. 

6. CONCLUSIONS AND RECOMMENDATIONS 

In developing the proposed regulations for LSI engines ≤ 1.0 L, staff’s goal was to 

achieve the greatest possible emission reductions in a technologically feasible and costeffective manner. Meeting the requirements of staff’s proposal is achievable using 

existing technologies and manufacturing processes, and the available lead time. The 

emission reductions are cost-effective when compared to recent control measures 

adopted by the Board. The proposed regulations are necessary to meet emissions 

reduction goals and to achieve health based ambient air quality standards. 

No alternatives considered by the Board would be more effective in achieving the 

purpose for which the regulations are proposed or would be as effective as or less 

burdensome to affected private persons than the proposed regulations. 

The staff recommends that the Board approve its proposal. 
28 

7. REFERENCES 

Air Resources Board, “Staff Report: Public Hearing to Consider Adoption of Emission 

Standards and Test Procedures for New 2001 and Later Off-Road Large Spark-Ignition 

Engines,” September 4, 1998. 

Air Resources Board, "Notice of Public Meeting to Consider the Approval of California’s 

Off-Road Large Spark-Ignited Engine Emissions Inventory,” California Air Resources 

Board, October 22, 1998. 

Manufacturers of Emission Controls Association (MECA), “MECA Responses to ARB 

Questions Regarding Closed-loop EFI Engine with Three Way Catalyst Technology for 

LSI Applications, prepared by Dr. Rasto Brezny, May 16, 2008. 

Southwest Research Institute (SwRI), ARB Contract No. 95-340, “Three-Way Catalyst 

Technology for Off-Road Equipment Powered by Gasoline and LPG Engines,” April 

1999. 

Southwest Research Institute, SwRI Project No. 08.05734, “Durability of Low-Emissions 

Small Off-Road Engines,” April 2004. 

U.S. EPA, 2002. “Control of Emissions from Nonroad Large Spark-Ignition Engines, and 

Recreational Engines (Marine and Land Based); Final Rule,” Federal Register, Volume 

67, Number 217, pages 68242 - 68447, November 8, 2002. 

U.S. EPA, 2007. “Control of Emissions from Nonroad Spark-Ignition Engines and 

Equipment; Proposed Rule,” Federal Register, Volume 72, pages 28097-28393, May 

18, 2007. 

U.S. EPA, 2008. “Regulatory Announcement: EPA Finalizes Emission Standards for 

New Nonroad Spark-Ignition Engines, Equipment, and Vessels, September 4, 2008. 
29 

APPENDIX A: Proposed Amendments to the Large Spark-Ignition Engines Exhaust 

Emission Regulation 
30 

APPENDIX B: Proposed Amendments to the California Exhaust and Evaporative 

Emission Standards and Test Procedures for New 2010 and Later OffRoad Large Spark-Ignition Engines