United States

Environmental Protection

Agency

Air and Radiation EPA420-P-02-015

November 2002

NR-010c

Exhaust Emission

Factors for Nonroad Engine

Modeling - Spark Ignition

 Printed on Recycled Paper
EPA420-P-02-015

November 2002

Exhaust Emission Factors for

Nonroad Engine Modeling - Spark Ignition

NR-010c

Assessment and Modeling Division

Office of Transportation and Air Quality

U.S. Environmental Protection Agency

NOTICE

This technical report does not necessarily represent final EPA decisions or positions.

It is intended to present technical analysis of issues using data that are currently available.

The purpose in the release of such reports is to facilitate the exchange of

technical information and to inform the public of technical developments which

may form the basis for a final EPA decision, position, or regulatory action.
NR-010c.wpd 1

Exhaust Emission Factors

 for Nonroad Engine Modeling--

Spark Ignition

Report No. NR-010c

revised November 27, 2002

Assessment and Standards Division

EPA, Office of Transportation and Air Quality

Purpose

This report describes and documents exhaust emission factors and brake specific fuel

consumption (BSFC) estimates used for spark ignition (SI) engines in EPA’s draft

NONROAD2002 emission inventory model. It covers engines powered by gasoline, natural gas

and liquefied petroleum gas.

Additional EPA reports describe other issues relating to emission factors including

NONROAD emission factors for evaporative emissions, crankcase emissions, spillage and other

non-exhaust emissions (NR-012a), adjustments to emission rates due to variations in fuel and

temperature (NR-001a), speciation of hydrocarbon emissions (NR-002), and adjustments to

emission rates as equipment deteriorates due to time and use (NR-011a). Emission factors for

compression ignition (diesel) engines are covered in a separate report (NR-009b).

Introduction

The U.S. EPA’s NONROAD model computes county-level emission inventories for

nonroad engines. These calculations rely on emission factors -- estimates of the amount of

pollution emitted by a particular type of equipment during a unit of use. Typically emission

factors for nonroad sources are reported in grams per horsepower-hour (g/hp-hr), but they also

may be reported in grams per mile (g/mile), grams per hour, grams per gallon, etc. The SI

exhaust emission factors in the NONROAD model are reported in g/hp-hr, with the exception of

nonroad motorcycles and all-terrain vehicles, which are reported in g/mile. The SI BSFCs are

reported in lb/hp-hr, with the exception of nonroad motorcycles and all-terrain vehicles, which

are reported in lb/mile.

 The pollutants covered by this report include exhaust total hydrocarbons (HC), carbon

monoxide (CO), oxides of nitrogen (NOx), total particulate matter (PM), carbon dioxide (CO2),

and sulfur dioxide (SO2). For nonroad engines, all PM emissions are assumed to be smaller than
NR-010c.wpd 2

10 microns (PM10), and 92% of the PM from gasoline and diesel fueled engines is assumed to be

smaller than 2.5 microns (PM2.5). For gaseous fueled engines (LPG/CNG), 100% of the PM

emissions are assumed to be smaller than PM2.5. The NONROAD Reporting Utility allows the

user to select the desired size range. 

Zero-mile, steady-state emission factors for HC, CO, NOx, PM, and steady-state BSFCs

are discussed first, followed by adjustments (where applicable) to account for transient operation. 

Technology distributions by model year, to account for changes in emission factors over time, are

then discussed. Derivation of CO2 and SO2 emission factors follows.

As explained in NR-006b, spark-ignition engine equipment population under 25

horsepower will be combined into one source classification code (SCC) per application to handle

expected shifts in market share between 2 and 4-stroke gasoline, LPG, and CNG engines. In the

model, the distinction between two- and four-stroke spark-ignition engine emission factors will

be maintained using the technology groups described in this report. In this current document, the

SCC distinction between 2 and 4-stroke gasoline, LPG, and CNG engines is maintained,

however, in the model, we will distinguish emission factors between them by using the

technology group methodology. 

Background

Prior to the NONROAD model, there have been three major efforts to estimate nonroad

spark ignition emission inventories. We have reviewed these efforts in our work to select

emission factors for the draft version of NONROAD. The three inventories/models are:

 EPA’s Nonroad Engine and Vehicle Emission Study (“NEVES”).[1] Published in

November, 1991, this study was mandated by Congress to determine whether nonroad

sources made a significant contribution to urban air pollution. The study covers

emissions from all nonroad engines and includes hydrocarbons (HC), carbon monoxide

(CO), nitrogen oxides (NOx), total particulates (PM), sulfur dioxide (SO2) and other

pollutants. It provides inventories for 19 ozone and 16 CO nonattainment areas.

 California Air Resources Board’s nonroad model (“OFF-ROAD”) [2], designed to

estimate nonroad emissions for the state of California only. A draft version of this model

was released August 1, 1997. The model covers HC, CO, NOx, PM, sulfur dioxide (SO2),

and carbon dioxide (CO2) for all nonroad engines. ARB periodically revises components

of the OFF-ROAD model.

 EPA’s “Small Engine Model”--designed as an internal tool for evaluating various control

scenarios, EPA has used this model to estimate the effect of regulations on small sparkignition (SI) engines under 19 kW (25 hp). This model has evolved over time, but the

pre-control exhaust emission factors have not changed since the model was documented
NR-010c.wpd 3

in 1995.[3] The model computes national-level inventories of nonroad HC, CO, and

NOx.

The emission factors used in these prior efforts have been based on a very small number

of engine studies, particularly when compared to the large body of data available for highway

vehicles. 

Emission Factor Categories

NEVES defines emission factors by the equipment use (i.e., by “application”) but does

not assign different emission factors to engines of different sizes within the same application. On

the other hand, OFF-ROAD and the Small Engine Model define emission factors by engine size

(by horsepower in OFF-ROAD and by displacement in the Small Engine Model), but do not

assign different emission factors to engines used in different applications that are of the same

size. Given the structure of emission control regulations and the design similarities between

engines of the same horsepower used in various applications, we define emission factors

primarily by power level in draft NONROAD2002. Appendix A provides a comparison of the

power categories in OFF-ROAD, the Small Engine Model, and NONROAD. The NONROAD

model allows for the use of application-specific emission factors if there is sufficient information

to justify their use. We use application-based emission factor categories only to distinguish

recreational marine engines and selected recreational vehicles.

Emission Standards

In addition to estimating emissions from pre-controlled engines, the NONROAD model is

designed to account for the effect of federal emissions standards. The model does not cover

California emission standards and federal standards that are not yet final. Thus, NONROAD will

include emission factors under the following final regulations that cover SI engines at or below

19 kilowatts (25 hp) and SI marine engines:

 Emissions for New Nonroad Spark Ignition Engines at or below 19 Kilowatts. (“Small

Engine Rule, Phase 1”) [4]

 Phase 2: Emission Standards for New Nonroad Nonhandheld Spark-Ignition Engines At

or Below 19 Kilowatts. (“Small Engine Nonhandheld Rule, Phase 2”) [5]

 Phase 2: Emission Standards for New Nonroad Spark-Ignition Handheld Engines At or

Below 19 Kilowatts and Minor Amendments to Emission Requirements Applicable to

Small Spark-Ignition Engines and Marine Spark-Ignition Engines. (“Small Engine

Handheld Rule, Phase 2”) [6]
NR-010c.wpd 4

 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 ("Marine Rule") [7]

There is also now a final rulemaking for large spark-ignition engines (> 25hp) and

recreational engines (both marine and land-based). [8] Since this rulemaking was just published

in November 2002, the final standards for these equipment categories are not included in this

version of the model, although updated pre-controlled emission factors developed as part of the

rulemaking process have been incorporated in draft NONROAD2002.

Zero-Hour, Steady-State Emission Factors for HC, CO, NOx, PM, and Steady-State BSFCs

This section describes the zero-hour, steady-state emission factors and steady-state

BSFCs that are used in draft NONROAD2002. Pre-controlled (baseline) and controlled (where

applicable) emission factors are described for each of the following regulatory equipment

categories: small SI engines 25 hp, large SI engines >25 hp, land-based recreational engines,

and recreational marine engines.

Spark-Ignition (SI) Engines 25 hp

This category includes all engines 25 hp except those used for recreational applications

(such as motorcycles or snowmobiles), for marine propulsion, or for toy boats and airplanes. The

engines in this category are used primarily in lawn and garden equipment.

For this category, engines are segregated by the class of the engine (I - V). Each class is

determined by the use of the engine, i.e., handheld or nonhandheld, and engine displacement. 

Classes I and II refer to nonhandheld small SI engines; classes III, IV, and V refer to handheld

small SI engines. The classes have the following displacements: Class I (< 225cc); Class II (

225cc); Class III (< 20cc); Class IV ( 20cc and < 50cc); Class V ( 50cc).

Each class in turn is subject to two phases of regulation (Phase 1 and Phase 2). Under the

Phase 1 regulations, new engines have had to meet emission standards for HC, CO, and NOx

since 1997. For nonhandheld applications (such as lawn and garden tractors and lawnmowers),

more stringent Phase 2 standards phase in between 2001 and 2007. For handheld applications

(such as leaf blowers and chainsaws), more stringent Phase 2 standards phase in between 2002

and 2007. The test procedure used for these regulations is the Small SI Engine Federal SteadyState Test Procedure.

Tables 1-5 contain the baseline and Phase 1 and 2 controlled emission factors for these

five classes of engines. There are no LPG or CNG engines less than 25 hp in draft

NONROAD2002; therefore, the emission factors in these tables are used for gasoline engines in

the model.
NR-010c.wpd 5

In order to account for the effect of the rulemaking and the phase-in of the new standards,

engines meeting the new standards were defined by the technology types in Tables 1-5. (A

complete list and description of SI technology types used in draft NONROAD2002 is provided in

Appendix B, Table B3.) Handheld engines (Classes III-V) are not expected to include any 4-

stroke engines (but emission factors are supplied for users) but are expected to include a small

fraction of catalyst equipped engines. Nonhandheld engines include both 2 and 4-stroke engines,

but manufacturers are expected to build only 4-stroke engines with the advent of the new

regulations. Nonhandheld 4-stroke engine production is split between two technical types, sidevalve and overhead valve systems, which have been shown to exhibit significantly different

emission characteristics.

In general, for baseline emissions, draft NONROAD2002 uses emission factors based on

those in the Small Engine Model. [3] Also, the PM emission factors for the entire category (both

baseline and controlled) are based on values in NEVES. [1]

For nonhandheld (class I and II) engines, NONROAD uses the brake-specific fuel

consumption (BSFC), HC, CO, and NOx emission factors for Phase 1 and 2 that are contained in

the final regulatory impact analysis. [9] (The baseline emission factors are also contained in this

reference.) The Phase 1 emission factors were based on values obtained from the EPA 1998

Phase 1 Certification database. For Phase 2, the emission factors were back-calculated using 1)

the Phase 2 standards, and 2) a multiplicative deterioration factor for each pollutant. The

deterioration factors are described in more detail in NR-011a.

For handheld (class III, IV, and V) engines, NONROAD also uses the BSFC, HC, CO,

and NOx emission factors for Phase 1 and 2 that are contained in the final regulatory impact

analysis. [10] (The baseline emission factors are also contained in this reference.) For Phase 1,

the emission factors were back-calculated using 1) the Phase 1 standards, and 2) a multiplicative

deterioration factor for each pollutant. For Phase 2, the emission factors were determined using

the same methodology. As mentioned above, the deterioration factors are described in more

detail in NR-011a. 

Table 1. Emissions and BSFCs for Class III Handheld Small SI Engines (< 20cc)*

Engine Tech Type HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

G2H3 (gas 2-stroke handheld Class III, baseline) 261.00 718.87 0.97 7.7 1.365

G2H31 (Phase 1) 219.99 480.31 0.78 7.7 1.184

G2H3C1 (Phase 1 with catalyst) 219.99 480.31 0.78 7.7 1.184

G2H32 (Phase 2) 33.07 283.37 0.91 7.7 0.822

G2H3C2 (Phase 2 with catalysts) 26.87 141.69 1.49 7.7 0.822

* Assigned NONROAD hp range: 0-1 hp
NR-010c.wpd 6

Table 2. Emissions and BSFCs for Class IV Handheld Small SI Engines (20cc and <50cc)*

Engine Tech Type HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

G2H4 (gas 2-stroke handheld Class IV, baseline) 261.00 718.87 0.94 7.7 1.365

G2H41 (Phase 1) 179.72 407.38 0.51 7.7 1.184

G2H4C1 (Phase 1 with catalyst) 179.72 407.38 0.51 7.7 1.184

G4H41 (Phase 1 4-stroke) 22.37 533.42 1.79 0.06 0.847

G2H42 (Phase 2) 33.07 283.37 0.91 7.7 0.822

G2H4C2 (Phase 2 with catalysts) 26.87 141.69 1.49 7.7 0.822

G4H42 (Phase 2 4-stroke) 25.83 432.51 1.13 0.06 0.847

* Assigned NONROAD hp range: 1-3 hp

Table 3. Emissions and BSFCs for Class V Handheld Small SI Engines (>50cc)*

Engine Tech Type HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

G2H5 (gas 2-stroke handheld Class V, baseline) 159.58 519.02 0.97 7.7 0.921

G2H51 (Phase 1) 120.06 351.02 1.82 7.7 0.870

G2H5C1 (Phase 1 with catalyst) 120.06 351.02 1.82 7.7 0.870

G2H52 (Phase 2) 47.98 283.37 0.91 7.7 0.608

G2H5C2 (Phase 2 with catalysts) 40.15 141.69 1.49 7.7 0.608

* Assigned NONROAD hp range: 3-6 hp
NR-010c.wpd 7

Table 4. Emissions and BSFCs for Class I Nonhandheld Small SI Engines (< 225cc)*

Engine Tech Type HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

G2N1 (gas 2-stroke nonhandheld Class I, baseline) 207.92 485.81 0.29 7.7 0.870

G4N1S (gas, side-valved, 4-stroke nonhandheld Class I,

baseline)

38.99 430.84 2.00 0.06 1.365

G4N1O (gas, overhead-valved, 4-stroke nonhandheld

Class I, baseline)

13.39 408.84 1.80 0.06 0.991

G2N11 (2-stroke, Phase 1) 120.06 449.66 4.00 7.7 0.870

G4N1S1 (Phase 1 side-valved, 4-stroke) 8.40 353.69 3.60 0.06 0.921

G4N1O1 (Phase 1 overhead valved 4-stroke) 8.40 351.16 3.24 0.06 0.781

G4N1SC1 (Phase 1 side-valved, 4-stroke with catalyst) 8.40 353.69 3.60 0.06 0.921

G4N1S2 (Phase 2 side-valved) 7.93 353.69 2.37 0.06 0.921

G4N1O2 (Phase 2 overhead valved) 6.13 351.16 1.83 0.06 0.781

* Assigned NONROAD hp range: 3-6 hp

Table 5. Emissions and BSFCs for Class II Nonhandheld Small SI Engines ( 225cc)*

Engine Tech Type HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

G2N2 (gas 2-stroke nonhandheld Class II, baseline) 207.92 485.81 0.29 7.7 0.870

G4N2S (gas, side-valved, 4-stroke nonhandheld Class

II, baseline)

9.66 430.84 2.06 0.06 0.937

G4N2O (gas, overhead-valved, 4-stroke nonhandheld

Class II, baseline)

5.20 408.84 3.50 0.06 0.937

G4N2S1 (Phase 1 side-valved, 4-stroke) 5.50 387.02 4.50 0.06 0.868

G4N2O1 (Phase 1 overhead valved 4-stroke) 5.20 352.57 3.50 0.06 0.740

G4N2S2 (Phase 2 side-valved) 5.50 387.02 4.50 0.06 0.868

G4N2O2 (Phase 2 overhead valved) 4.16 352.57 2.77 0.06 0.740

* Assigned NONROAD hp range: 6-25 hp

Spark-Ignition Engines > 25 hp

 Nonroad SI engines above 25 hp are generally found in industrial equipment and are used

in a wide variety of applications, including forklifts, airport ground-service equipment,

generators, compressors, welders, aerial lifts, and ice grooming machines. These engines may
NR-010c.wpd 8

operate on gasoline, LPG, or CNG. SI engines >25 hp are currently unregulated, although

emission standards have recently been proposed. [8] As a result, only pre-controlled (baseline)

emission factors are included in draft NONROAD2002.

A summary of the emission factors used for this equipment category is provided in Table

6. The gasoline 2-stroke engine emission factors and the PM emission factors generally were

taken from NEVES. [1] Emission factors for the gasoline 4-stroke, LPG, and CNG engines were

taken from the draft regulatory support document for the proposed rule, and are based on a

summary of available test data. [11]

Table 6. Emissions and BSFCs for Spark-Ignition Engines > 25 hp *

Engine Tech Type HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

G2GT25 (gas, 2-stroke, baseline) 208.00 486.00 0.290 7.70 1.30

G4GT25 (gas, 4-stroke, baseline) 6.22 203.4 7.130 0.06 0.605

LGT25 (LPG, baseline) 1.68 28.23 11.99 0.05 0.507

NGT25 (CNG, baseline) 24.64 28.23 11.99 0.05 0.507

* These are pre-control emission factors, as this category of nonroad engines is currently not subject to regulation.

These emission factors are also used for 2-stroke and 4-stroke snowblowers <25hp, since snowblowers are currently

not regulated.

Snowmobiles are categorized as recreational equipment, and are covered under a different tech type (R12S).

Motorcycles, All-Terrain Vehicles (ATVs), and Snowmobiles

These engines differ significantly from other SI engines in their basic design, operating

characteristics, and emission rates. They are currently unregulated, although emission standards

have recently been proposed. [8] As a result, only pre-controlled (baseline) emission factors are

included in draft NONROAD2002.

A summary of the emission factors for these engines is provided in Table 7. The HC,

CO, and NOx emission data for ATVs and motorcycles were provided by a manufacturer and

represent various makes, models, model years, and engine sizes. The emission factors for ATVs

and motorcycles are expressed as gram/mile (lb/mile for BSFC). The HC, CO, and NOx test data

used for snowmobiles came from the International Snowmobile Manufacturers Association

(ISMA) and Southwest Research Institute (SwRI). The emission factors for snowmobiles are

expressed as gram/hp-hr (lb/hp-hr for BSFC). The emission factors are documented in regulatory

support documents for the proposed rule. [11,12]
NR-010c.wpd 9

Table 7. Emissions and BSFCs for Motorcycles, ATVs, and Snowmobiles

Equipment/Tech Type HC

g/mile

CO

g/mile

NOx

g/mile

PM

g/mile

BSFC

lb/mile

2-stroke offroad motorcycle (R12S) 55.7 52.7 0.150 0.016 0.291

4-stroke offroad motorcycle (R14S) 2.2 48.3 0.340 0.011 0.170

2-stroke all terrain vehicles (R12S) 55.7 52.7 0.150 0.016 0.197

4-stroke all terrain vehicles (R14S) 2.2 48.3 0.340 0.022 0.332

HC

g/hp-hr

CO

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

2-stroke snowmobiles (R12S) 111.0 296.0 0.860 2.70 1.66

Recreational SI Marine Engines

Recreational SI marine engines are divided into three categories: outboard, personal

watercraft (PWC), and sterndrive/inboard engines. Emission factors (HC, CO, and NOx) for

these engines were taken from work accomplished in support of the 1996 rulemaking for new

emission standards for these engines, as well as newer information and analysis related to SI

inboard engines. [13,14] BSFCs and PM emission factors were derived from NEVES. [1] 

Table 8 shows how the power level ranges used in the 1996 rulemaking analysis were matched to

the power levels used in NONROAD. Tables 9-12 show the emission rates by power range for

precontrolled outboard, PWC, and inboard engines. 

To determine the effect of the Federal rulemaking for these types of engines, technical

types were defined to reflect new technologies that would be employed to meet the emission

levels required. These new technologies would be employed to various degrees to reflect the

phase-in of the new emission standards. Technical types were defined to incorporate the

emission reductions expected and the phase-in of the standards.

The precontrolled outboard two-stroke and four-stroke engines were defined by the

technical types M1 and M4. Four additional engine technical types (M5, M6, M8, and M9) were

defined to account for the new standards and allows for phase-in of the standards. Emission

factors for these technical types are given in Tables 13-16.
NR-010c.wpd 10

Table 8. Mapping of Recreational Marine Engine Power Ranges

EPA-RIA NONROAD Model

Outboard <3.9 hp 0 - 3 hp

3.9 - 9.9 3 - 11

9.9 - 29.9 11 - 25

29.9 - 49.9 25 - 50

49.9 - 74.9 -------

74.9 - 99.9 50 - 100

99.9 - 149.9 -------

149.9 - 199.9 100 - 175

PWC 30 - 50 hp 0 - 50 hp

50 - 75 50 - 175

Inboard 100 - 150 hp 0 - 100 hp

150 - 200 100 - 175

>200 >175

Table 9. Two-Stroke Outboard (SCC - 2282005010) Emission Factors and BSFCs for

Precontrolled Engines (M1 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 3 hp 254.01 396.5 3.072 7.7 1.3

3 - 11 218.43 335.7 2.521 7.7 1.3

11 - 25 164.49 301.4 1.002 7.7 1.3

25 - 50 116.38 231.3 1.190 7.7 1.3

50 - 100 101.95 233.5 1.833 7.7 1.3

100 - 175 128.69 313.3 4.476 7.7 1.3

>175 128.69 313.3 4.476 7.7 1.3
NR-010c.wpd 11

Table 10. Four-Stroke Outboard (SCC - 2282005010) Emission Factors and BSFCs for

Precontrolled Engines (M4 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 3 hp 90.42 436.4 3.678 0.06 0.7

3 - 11 22.16 436.4 3.879 0.06 0.7

11 - 25 13.70 339.2 5.953 0.06 0.7

25 - 50 14.92 339.2 7.460 0.06 0.7

50 - 100 8.21 258.1 7.460 0.06 0.7

100 - 175 7.46 258.1 8.952 0.06 0.7

>175 7.46 258.1 8.952 0.06 0.7

Table 11. Personal Watercraft (SCC - 2282005015) Precontrolled Emission Factors and BSFCs

(M2 Tech Type. For 4-stroke see Tech Type M13 in Table 17)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 50 hp 135.10 257.9 0.701 7.7 1.3

50 - 175 153.66 252.7 1.001 7.7 1.3

Table 12. Inboard (SCC - 2282010005) Precontrolled Emission Factors and BSFCs 

(M3 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

all 5.88 153.7 5.350 0.06 0.7
NR-010c.wpd 12

Table 13. Two-Stroke Outboard (SCC - 2282005010) Emission Factors and BSFCs with

Carburetor & Ignition Modifications (M5 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 3 hp 254.01 484.9 3.072 7.7 1.3

3 - 11 218.43 484.9 2.521 7.7 1.3

11 - 25 161.51 430.8 1.002 7.7 1.3

25 - 50 116.38 422.2 1.190 7.7 1.3

50 - 100 101.95 276.0 1.833 7.7 1.3

100 - 175 115.63 289.4 8.206 7.7 1.3

>175 115.63 289.4 8.206 7.7 1.3

Table 14. Two-Stroke Outboard (SCC - 2282005010) Emission Factors and BSFCs with

Modifications and Catalyst (M6 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 3 hp 123.69 311.5 2.560 7.7 1.3

3 - 11 106.37 263.8 2.101 7.7 1.3

11 - 25 80.10 236.8 0.835 7.7 1.3

25 - 50 56.67 181.7 0.992 7.7 1.3

50 - 100 49.65 183.5 1.527 7.7 1.3

100 - 175 62.66 246.2 3.730 7.7 1.3

>175 62.66 246.2 3.730 7.7 1.3
NR-010c.wpd 13

Table 15. Two-Stroke Outboard (SCC - 2282005010) Emission Factors and BSFCs with

Electronic Fuel Injection (M8 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 3 hp 45.59 466.8 15.406 7.7 1.3

3 - 11 39.21 395.3 12.647 7.7 1.3

11 - 25 29.52 354.9 5.023 7.7 1.3

25 - 50 20.89 272.3 5.968 7.7 1.3

50 - 100 19.77 255.5 7.087 7.7 1.3

100 - 175 19.15 242.5 8.206 7.7 1.3

>175 18.65 242.5 8.206 7.7 1.3

Table 16. Direct-Injection Type A Outboard (SCC - 2282005010) Emission Factors and BSFCs

(M9 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 3 hp 57.60 430.8 11.440 7.7 1.3

3 - 11 49.53 364.8 9.391 7.7 1.3

11 - 25 37.30 327.5 3.730 7.7 1.3

25 - 50 28.35 194.7 3.730 7.7 1.3

50 - 100 32.08 191.0 3.730 7.7 1.3

100 - 175 40.28 305.5 3.730 7.7 1.3

>175 38.05 284.2 3.730 7.7 1.3

Personal watercraft (PWC) emissions are characterized by three technical types: 2-stroke

(labeled M2), 4-stroke (M13), and 2-stroke with major modifications (M14). Type M2 has the

emission factors given above in Table 11. The emission factors for the M13 and M14 technical

types are given in Tables 17 and 18, respectively.
NR-010c.wpd 14

Table 17. Personal Watercraft (SCC - 2282005015) 4-Stroke Emission Factors and BSFCs 

(M13 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 50 hp 11.56 256.3 4.821 0.06 0.7

50 - 175 12.73 252.4 5.437 0.06 0.7

Table 18. Personal Watercraft (SCC - 2282005015) 2-Stroke with Major Modifications Emission

Factors and BSFCs (M14 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

0 - 50 hp 127.69 269.6 1.268 7.7 1.3

50 - 175 143.78 258.6 0.837 7.7 1.3

The sterndrive/inboard market has changed considerably over the past five or six years. 

Electronic fuel injection is used on more than half of new engine sales. Based on industry trends,

we predict that most, if not all, inboard engines will be fuel injected by 2004. In NONROAD,

the technology type for engines using electronic fuel injection is designated as M10. Table 19

presents the emission factors for the M10 technology type.

Table 19. Inboard (SCC - 2282010005) with Electronic Fuel Injection Emission Factors and

BSFCs (M10 Tech Type)

 NONROAD

power range

HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

all 3.02 71.8 8.480 0.06 0.7

Accounting for In-Use Operation

Many nonroad engines operate under transient loads, but the engines are typically tested

with steady-state tests. For small SI engines (25 hp), three studies have compared transient and

steady-state emissions in SI engines, but they have not found consistent results and, in most

cases, transient and steady-state have produced equivalent emission factors. [15,16,17] At

present, EPA believes there is not sufficient information to justify an in-use transient adjustment

factor (TAF) for small SI engines, so the NONROAD model will use emission factors based on

unadjusted steady-state test results. Similarly, TAFs are not applied to the zero hour, steady-state

emission factors for recreational equipment and SI marine engines.
NR-010c.wpd 15

For large SI engines >25 hp, based on emission measurements from highway engines

comparable to uncontrolled large SI engines, transient emission levels are 30 percent higher for

HC and 45 percent higher for CO relative to steady-state measurements. [11, 18] The

NONROAD model therefore multiplies steady-state emission factors for SI engines >25 hp by a

TAF of 1.3 for HC and 1.45 for CO to estimate emission levels during normal, transient

operation. Test data do not support adjusting NOx emission levels for transient operation and so

a TAF of 1.0 is used for NOX emissions. Also, the model applies no TAFs for generators,

pumps, or compressors, since engines in these applications are less likely to experience transient

operation. A summary of the TAFs used for large SI engines >25 hp is provided in Table 20.

Table 20. Transient Adjustment Factors for Spark-Ignition Engines >25 hp

Tech Types HC 

g/hp-hr

CO 

g/hp-hr

NOx

g/hp-hr

PM

g/hp-hr

BSFC

lb/hp-hr

all* 1.3 1.45 1.0 1.0 1.0

* All = gasoline 2-stroke (G2GT25), gasoline 4-stroke (G4GT25), LPG (LGT25), and CNG (NGT25) engines.

TAFs are not applied to generator sets, pumps, or air compressors, as these are less likely to experience transient

operation.

Technology Distributions

NONROAD accounts for changes in sales fractions and emissions from the advent of

emission standards or other changes by assigning technology groups to each Source

Classification Code (SCC). Each technology group has its own emission factors as described

above, and the fraction of the population assigned to each group can change over time. These

“technology fractions” by year are contained in an input file in NONROAD called tech.dat.

The regulations previously discussed for small SI and SI recreational marine engines are

expected to influence the sales fraction of various technology types and the emission rates of

those technologies. These anticipated changes are described in the regulatory support documents

for the rulemakings. In draft NONROAD2002, EPA simply formats this information for the

NONROAD input files.

The technology fractions by SCC in tech.dat are provided in Appendix B.

Carbon Dioxide Emission Factors

Emission factors for CO2 are rarely measured; instead, they typically are calculated based

on brake-specific fuel consumption (BSFC). The NONROAD model uses BSFC to compute

CO2 emissions directly, as shown in the equation below. The carbon that goes to exhaust HC

emissions is subtracted. This does not require a CO2 emission factors input file.
NR-010c.wpd 16

 CO2 = (BSFC * 453.6* - HC) * 0.87 * (44/12)

where

CO2 is in g/hp-hr

BSFC is the fuel consumption in lb/hp-hr

453.6 is the conversion factor from pounds to grams

HC is the in-use adjusted hydrocarbon emissions in g/hp-hr

0.87 is the carbon mass fraction of diesel

44/12 is the ratio of CO2 mass to carbon mass

Sulfur Dioxide Emission Factors

 Sulfur dioxide emissions are rarely measured. Instead, they typically are calculated from

fuel consumption and fuel sulfur content. We have retained this approach for the NONROAD

model. Sulfur dioxide emission factors for gasoline engines are calculated using the following

equation: 

 SO2 = (BSFC * 453.6* (1 - soxcnv) - HC) * 0.01 * soxbas * 2

where

SO2 is in g/hp-hr

BSFC is the fuel consumption in lb/hp-hr

453.6 is the conversion factor from pounds to grams

soxcnv is the fraction of fuel sulfur converted to direct PM (soxcnv = 0.03 for

gasoline engines)

HC is the in-use adjusted hydrocarbon emissions in g/hp-hr

0.01 is the conversion factor from weight percent to weight fraction

soxbas is the episodic weight percent of sulfur in the fuel (default value for

gasoline is 0.0339)

2 is the grams of SO2 formed from a gram of sulfur

The calculation for CNG/LPG engines is similar, with an average default fuel sulfur

weight percent (soxbas) of 0.008 and the same sulfur conversion rate (soxcnv = 0.03). 

The SO2 emission factors are calculated based on the default fuel sulfur contents listed

here. NONROAD users may use the model interface to adjust the fuel sulfur content without

changing the input files.

Note that this version of the model corrects errors in the equation to calculate SO2

emissions. In previous versions, the conversion from g/hp-hr to g/hr was missing the load factor

term. The net effect of making this correction was to lower SO2 by roughly 40-50 percent.
NR-010c.wpd 17

References

[1] “Nonroad Engine and Vehicle Emission Study” (NEVES), U.S. EPA, Office of Air and

Radiation, 21A-2001, November, 1991.

[2] “Documentation of Input Factors for the New Off-Road Mobile Source Emissions Inventory

Model,” (“Inputs...”) Energy and Environmental Analysis, Inc. for California Air Resources

Board, February, 1997.

[3] “Documentation of the OMS Small Gasoline Engine Spreadsheet System, Final Technical

Memorandum,” Dan Bowman, TRC Environmental Corporation, August 1995.

[4] “Emissions for New Nonroad Spark-Ignition Engines At or Below 19 Kilowatts; Final

Rule,” 60 FR 34581, July 3, 1995.

[5] “Phase 2: Emission Standards for New Nonroad Nonhandheld Spark Ignition Engines At or

Below 19 Kilowatts,” Amendments to 40 CFR Part 90, March 1999.

[6] “Phase 2: Emission Standards for New Nonroad Spark-Ignition Handheld Engines At or

Below 19 Kilowatts and Minor Amendments to Emission Requirements Applicable to Small

Spark-Ignition Engines and Marine Spark-Ignition Engines; Final Rule,” 65 FR 24268, April 25,

2000.

[7] “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,” 61 FR 52088, October 4, 1996.

[8] “Control of Emissions From Nonroad Large Spark-Ignition Engines and Recreational

Engines (Marine and Land-Based); Final Rule,” 67 FR 68241, November 8, 2002.

[9] “Final Regulatory Impact Analysis, Phase 2: Emission Standards for New Nonroad

Nonhandheld Spark-Ignition Engines At or Below 19 Kilowatts,” U.S. EPA, EPA420-R-99-003,

March 1999.

[10] “Final Regulatory Impact Analysis, Phase 2 Final Rule: Emission Standards for New

Nonroad Handheld Spark-Ignition Engines At or Below 19 Kilowatts,” U.S. EPA, EPA420-R00-004, March 2000.

[11] “Draft Regulatory Support Document: Control of Emissions from Unregulated Nonroad

Engines,” U.S. EPA, EPA420-D-01-004, September 2001.

[12] “Emission Modeling for Recreational Vehicles,” EPA Memorandum from Linc Wehrly to

Docket A-98-01, EPA420-F-00-051, November 13, 2000.
NR-010c.wpd 18

[13] “Regulatory Impact Analysis: Control of Air Pollution Emission Standards for New

Spark-Ignition Marine Engines,” U.S. EPA, October, 1996.

[14] “Revisions to the June 2000 Release of NONROAD to Reflect New Information and

Analysis on Marine and Industrial Engines,” EPA Memorandum from Mike Samulski to Docket

A-98-01, Docket Item IV-8-1, November 2, 2000.

[15] “Emissions Analysis of Small Utility Engines.” Sun, X., et al. SAE paper 952080. 1995.

[16] “Emissions from 4-Cycle Walk-Behind-Mower Engines: Test Cycle Effects.” Gabele,

Peter. SAE Paper 972793. 1997

[17] “Transient versus steady-state test procedure evaluation of 4-cycle utility engines,”

Carpenter, T., Buszkiewicz, T., Trimble, T. EPA regulation negotiation test procedure task

group, November, 1994. EPA Air Docket A-93-29, Docket Item II-M-27 and “Final Report -

Handheld Subgroup of the Test Procedure Task Group", EPA Air Docket A-93-29, Docket Item

II-M-40.

[18] “Regulatory Analysis and Environmental Impact of Final Emission Regulations for 1984

and Later Model Year Heavy Duty Engines,” p. 189, U.S. EPA, Docket A-2000-01, December

1979.
NR-010c.wpd A1

Appendix A

Cross-Inventory Comparison of SI Emission Factors

Comparing emission factors between inventory models (NEVES, OFF-ROAD, EPA’s

Small Engine Model) is not straightforward because the different models and inventories use

different units and different categories in distinguishing emission factors. To compare the

factors, all factors were converted to list emission factors in g/hp-hr by engine type, application

and horsepower. This conversion required mapping both the ARB horsepower groups and the

Small Engine Model’s displacement classes to the horsepower groups used by the NONROAD

model (see Tables A1 and A2). It was also necessary to combine the Small Engine Model’s

overhead-valve and side-valve categories into a single category by using a sales-weighted

average, using the sales mix listed in Table A3.

Table A1. Mapping of small engine groupings used in the Small Engine Model and ARB’s OFFROAD model to the small engine groupings used in the NONROAD model

Small Engine Model

Class/Displacement

ARB Power 

Range

NONROAD

Power Range

NONROAD 

source classification

Non-Handheld, I 

<225 cc

2-5 hp 3-6 hp All engines except 2-stroke

trimmers/edgers/cutters, chainsaws,

leafblowers, and snowblowers

Non-Handheld, II 

>225 cc

5-15 hp

15-25 hp

6-16 hp 

16-25 hp

All engines except 2-stroke

trimmers/edgers/cutters, chainsaws,

leafblowers, and snowblowers

Handheld, III 

0-20 cc

 2 hp 0-1 hp All engines

Handheld, IV 

20-50 cc

 2 hp 1-3 hp All engines

Handheld, V 

>50 cc

 2-15 hp 3-6 hp All 2-stroke trimmers/edgers/cutters,

chainsaws, leafblowers, and

snowblowers
NR-010c.wpd A2

Table A2. Mapping of large engine groupings used in ARB’s OFF-ROAD model to the large

engine groupings used in the NONROAD model.

ARB hp range NONROAD hp Range

5-15 6-11 & 11-16

15-25 16-25

25-50 25-50

50-120 50-100

120-175 100-175

175-250 175-250

250-500 250-500

500-750 500-750

750-9999 750-3000+
NR-010c.wpd A3

Table A3. Sales Mix for Small Engine Model, Pre-control [1]

Application Sales Mix

2-stroke handheld 2-stroke nonhandheld 4-stroke non-handheld, overhead- and side-valveClass 3 Class 4 Class 5 Class 1 Class 2 Class 1

OHV

Class 1SV

Class 2OHV

Class 2SV

Lawn Mowers 0.1 0.065 0.835 0.0014Trimmers/Edgers/ Cutters

0.0501 0.9173 0.0077 0.0016 0.0231 0.0002

Chain Saws 0.0035 0.6426 0.3539Leaf Blowers/Vacuums

0.0528 0.6299 0.2086 0.0007 0.0721 0.0001 0.0359

Generator Sets 0.0017 0.0057 0.2853 0.0551 0.6522Tillers 0.0101 0 0.7938 0.0001 0.196Snowblowers 0.3205 0.3732 0.3063CommercialTurf Equipment

0.0099 0.04 0.0647 0.3658 0.5196

Rear EngineRiding Mowers

0.0499 0.1563 0.7939

Lawn & GardenTractors

0.0222 0.804 0.0013 0.1725

Pumps 0.0049 0.1421 0.8531All OtherEquipment

0.0974 0.0024 0.0375 0.4064 0.0081 0.4482

[1]“Documentation of the OMS Small Gasoline Engine Spreadsheet System, Final Technical Memorandum” TRC Environmental

Corporation for U.S. EPA Air and Energy Research Laboratory. August 1995.
NR-010c.wpd B1

Appendix B

Technology Groups and Distributions by Year

NONROAD accounts for changes in sales fractions and emissions from the advent of

emission standards or other changes by assigning technology groups to each Source

Classification Code (SCC). (SCC descriptions are given in NR-006b.) Each technology group

has its own emission factor and the fraction of the population assigned to each group can change

over time. These “technology fractions” are contained in an input file in NONROAD called

tech.dat. A sample record for 4-stroke lawnmowers might show a shift in engine sales from

side-valve engines (Tech Group 1) to overhead valve engines (Tech Group 2) as illustrated in

Table B1, which shows side-valve engines declining from 90% of sales in 1991 to 50% of sales

in 1997.

Table B1. Sample Technology Fractions

SCC/Year Horsepower

Range

Tech

group/fraction

Tech

group/fraction

2260004010 3-6 hp 1 2

1990 0.90 0.10

1997 0.50 0.50

Each technology group has an associated emission factor given in the emission factor

input file for that pollutant. This emission factor can change with time. For example, CO

emissions from Technology Group 1 (side-valve engines) might decrease from 819 g/hp-hr for

model year engines 1990 through 1996 to 387 g/hp-hr for model years 1997 and later as shown in

Table B2. The year listed in the emission factor input file is the first year in which the new

emission factor applies.

Table B2. Sample Emission Factors

SCC/Year Horsepower

Range

Technology

group/emissions

Units Pollutant

2265004010 3-6 hp 1 g/hp-hr CO

1990 819

2265004010 3-6 hp 1 g/hp-hr CO

1997 387
NR-010c.wpd B2

 For pre-controlled engines, the only technology groups currently identified are those used

to combine SCCs for spark-ignition engines <25 hp as described in NR-006b. Technology

groups primarily will be used for engines subject to emissions regulations. The regulations

discussed in the main body of this report (for small SI engines 25 hp and SI recreational marine

engines) are expected to influence the sales fraction of various technology types and the emission

rates of those technologies. The technology types meeting the new standards (with appropriately

lower emission factors) then gain market share during the appropriate model years which

represent the start year of the regulations. These anticipated changes are described in EPA’s

rulemakings. In draft NONROAD2002, EPA simply formats this information for the

NONROAD input files.

Table B3 provides a list and description of the SI technology groups used in draft

NONROAD2002. Tables B4-B17 contain the technology fractions in tech.dat.

If new emission factors are developed for other parts of the inventory (e.g., larger SI

engines) to reflect distinctions between different engine technologies with different emission

levels, then appropriate technology groups, technology fractions, and emission factors will be

added to the model. Similarly, appropriate emission factors will be added to the model if new

emission standards are implemented.

Table B3. Spark-Ignition Technologies in the Draft NONROAD2002 Model

Engine Tech

Type Code

SI Engine Category Description

G2GT25 Large SI > 25hp Gasoline, 2-stroke, Baseline

G2H3 Small SI  25hp Gasoline, 2-stroke, handheld Class III (<20cc), Baseline

G2H31 Small SI  25hp Gasoline, 2-stroke, handheld Class III (<20cc), Phase 1

G2H3C1 Small SI  25hp Gasoline, 2-stroke, handheld Class III (<20cc), Phase 1 with

catalyst

G2H32 Small SI  25hp Gasoline, 2-stroke, handheld Class III (<20cc), Phase 2

G2H3C2 Small SI  25hp Gasoline, 2-stroke, handheld Class III (<20cc), Phase 2 with

catalyst

G2H4 Small SI  25hp Gasoline, 2-stroke, handheld Class IV (20cc and <50cc), Baseline

G2H41 Small SI  25hp Gasoline, 2-stroke, handheld Class IV (20cc and <50cc), Phase 1

G2H4C1 Small SI  25hp Gasoline, 2-stroke, handheld Class IV (20cc and <50cc), Phase 1

with catalyst

G2H42 Small SI  25hp Gasoline, 2-stroke, handheld Class IV (20cc and <50cc), Phase 2

G2H4C2 Small SI  25hp Gasoline, 2-stroke, handheld Class IV (20cc and <50cc), Phase 2

with catalyst
Table B3. Spark-Ignition Technologies in the Draft NONROAD2002 Model

Engine Tech

Type Code

SI Engine Category Description

NR-010c.wpd B3

G2H5 Small SI  25hp Gasoline, 2-stroke, handheld Class V (>50cc), Baseline

G2H51 Small SI  25hp Gasoline, 2-stroke, handheld Class V (>50cc), Phase 1

G2H5C1 Small SI  25hp Gasoline, 2-stroke, handheld Class V (>50cc), Phase 1 with catalyst

G2H52 Small SI  25hp Gasoline, 2-stroke, handheld Class V (>50cc), Phase 2

G2H5C2 Small SI  25hp Gasoline, 2-stroke, handheld Class V (>50cc), Phase 2 with catalyst

G2N1 Small SI  25hp Gasoline, 2-stroke, nonhandheld Class I (<225cc), Baseline

G2N11 Small SI  25hp Gasoline, 2-stroke, nonhandheld Class I (<225cc), Phase 1

G2N2 Small SI  25hp Gasoline, 2-stroke, nonhandheld Class II (225cc), Baseline

G4GT25 Large SI > 25hp Gasoline, 4-stroke, Baseline

G4H41 Small SI  25hp Gasoline, 4-stroke, handheld Class IV (20cc and <50cc), Phase 1

G4H42 Small SI  25hp Gasoline, 4-stroke, handheld Class IV (20cc and <50cc), Phase 2

G4N1O Small SI  25hp Gasoline, 4-stroke, overhead-valved, nonhandheld Class I

(<225cc), Baseline

G4N1O1 Small SI  25hp Gasoline, 4-stroke, overhead-valved, nonhandheld Class I

(<225cc), Phase 1

G4N1O2 Small SI  25hp Gasoline, 4-stroke, overhead-valved, nonhandheld Class I

(<225cc), Phase 2

G4N1S Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class I (<225cc),

Baseline

G4N1S1 Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class I (<225cc),

Phase 1

G4N1SC1 Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class I (<225cc),

Phase 1 with catalyst

G4N1S2 Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class I (<225cc),

Phase 2

G4N2O Small SI  25hp Gasoline, 4-stroke, overhead-valved, nonhandheld Class II

(225cc), Baseline

G4N2O1 Small SI  25hp Gasoline, 4-stroke, overhead-valved, nonhandheld Class II

(225cc), Phase 1

G4N2O2 Small SI  25hp Gasoline, 4-stroke, overhead-valved, nonhandheld Class II 

(225cc), Phase 2
Table B3. Spark-Ignition Technologies in the Draft NONROAD2002 Model

Engine Tech

Type Code

SI Engine Category Description

NR-010c.wpd B4

G4N2S Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class II (225cc),

Baseline

G4N2S1 Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class II (225cc),

Phase 1

G4N2S2 Small SI  25hp Gasoline, 4-stroke, side-valved, nonhandheld Class II (225cc),

Phase 2

LGT25 Large SI > 25hp Liquid Petroleum Gas, Baseline

M1 Recreational Marine Outboard, 2-stroke, Baseline

M2 Recreational Marine Personal Watercraft, 2-stroke, Baseline

M3 Recreational Marine Inboard, Baseline

M4 Recreational Marine Outboard, 4-stroke, Baseline

M5 Recreational Marine Outboard, 2-stroke, with carburetor and ignition modifications

M6 Recreational Marine Outboard, 2-stroke, with modifications and catalyst

M8 Recreational Marine Outboard, 2-stroke, with electronic fuel injection

M9 Recreational Marine Outboard, direct-injection

M10 Recreational Marine Inboard, with electronic fuel injection

M13 Recreational Marine Personal Watercraft, 4-stroke, Baseline

M14 Recreational Marine Personal Watercraft, 2-stroke, with major modifications

NGT25 Large SI > 25hp Compressed Natural Gas, Baseline

R12S Recreational Equipment Offroad Motorcycles, All-Terrain Vehicles, and Snowmobiles, 2-

stroke, Baseline

R14S Recreational Equipment Offroad Motorcycles, All-Terrain Vehicles, and Snowmobiles, 4-

stroke, Baseline
NR-010c.wpd B5

Table B4. Technical Type Fleet Fractions for 3 - 11 hp Outboard Engines

Year M1 M4 M5

1900 0.957 0.043 0.000

1997 0.870 0.130 0.000

2000 0.537 0.463 0.000

2003 0.276 0.724 0.000

2005 0.260 0.724 0.016

Table B5. Technical Type Fleet Fractions for 11 - 25 hp Outboard Engines

Year M1 M4 M5 M9

1900 0.989 0.011 0.000 0.000

2002 0.962 0.038 0.000 0.000

2003 0.780 0.216 0.004 0.000

2004 0.640 0.349 0.011 0.000

2005 0.633 0.356 0.011 0.000

2006 0.091 0.620 0.011 0.277

Table B6. Technical Type Fleet Fractions for 25 - 50 hp Outboard Engines

Year M1 M4 M5 M8 M9

1900 1.000 0.000 0.000 0.000 0.000

1998 0.972 0.028 0.000 0.000 0.000

2001 0.683 0.049 0.000 0.268 0.000

2002 0.105 0.049 0.000 0.268 0.578

2003 0.098 0.049 0.007 0.268 0.578

2005 0.085 0.063 0.007 0.268 0.578
NR-010c.wpd B6

Table B7. Technical Type Fleet Fractions for 50 - 100 hp Outboard Engines

Year M1 M4 M5

1900 1.000 0.000 0.000

1999 0.950 0.050 0.000

2000 0.917 0.050 0.033

Table B8. Technical Type Fleet Fractions for 100- 175 hp Outboard Engines

Year M1 M5 M6 M8 M9

1900 1.000 0.000 0.000 0.000 0.000

1997 0.988 0.000 0.000 0.012 0.000

1998 0.954 0.034 0.000 0.012 0.000

1999 0.575 0.034 0.000 0.012 0.379

2003 0.302 0.035 0.267 0.012 0.384

2004 0.000 0.035 0.267 0.314 0.384

Table B9. Technical Type Fleet Fractions for >175 hp Outboard Engines

Year M1 M8 M9

1900 1.000 0.000 0.000

1997 0.967 0.033 0.000

1998 0.234 0.033 0.733

2004 0.000 0.290 0.710

Table B10. Technical Type Fleet Fractions of New Personal Water Craft Engines 0-25 hp*

Year M2 M13

1900 0.218 0.782

2005 0.075 0.925

* The RIA assumed there were no engines under 30hp. As described in technical report NR-006b, "Nonroad Engine

Population Estimates," the PSR data that NONROAD uses as a basis for most of the SI engine population inputs

does indicate some engines in this power range, including some 4-strokes. Draft NONROAD2002 takes into account

those PSR population fractions.
NR-010c.wpd B7

Table B11. Technical Type Fleet Fractions of New Personal Water Craft Engines 25-50 hp

Year M2 M13 M14

1900 1.000 0.000 0.000

1999 0.680 0.000 0.320

2002 0.680 0.136 0.184

2003 0.496 0.320 0.184

2004 0.496 0.504 0.000

2005 0.075 0.925 0.000

Table B12. Technical Type Fleet Fractions of New Personal Water Craft Engines >50 hp

Year M2 M13 M14

1900 1.000 0.000 0.000

1999 0.177 0.092 0.731

2000 0.177 0.259 0.564

2001 0.177 0.533 0.290

2002 0.177 0.823 0.000

2004 0.039 0.961 0.000

Table B13. Technical Type Fleet Fractions of New Inboard Engines <50 hp

Year M3 M10

1900 1.000 0.000
NR-010c.wpd B8

Table B14. Technical Type Fleet Fractions of New Inboard Engines 50-175 hp

Year M3 M10

1900 1.000 0.000

1997 0.900 0.100

1998 0.800 0.200

1999 0.700 0.300

2000 0.600 0.400

2001 0.500 0.500

2002 0.400 0.600

2003 0.300 0.700

2004 0.200 0.800

Table B15. Technical Type Fleet Fractions of New Inboard Engines 175-300 hp

Year M3 M10

1900 1.000 0.000

1996 0.900 0.100

1997 0.800 0.200

1998 0.700 0.300

1999 0.600 0.400

2000 0.500 0.500

2001 0.400 0.600

2002 0.300 0.700

2003 0.200 0.800

2004 0.100 0.900
NR-010c.wpd B9

Table B16. Technical Type Fleet Fractions of New Inboard Engines >300 hp

Year M3 M10

1900 1.000 0.000

1995 0.900 0.100

1996 0.800 0.200

1997 0.700 0.300

1998 0.600 0.400

1999 0.500 0.500

2000 0.400 0.600

2001 0.300 0.700

2002 0.200 0.800

2003 0.100 0.900

2004 0.000 1.000
NR-010c.wpd B10

Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*Year SCC HPmn HPmx Fraction of Population in Each Technology Type

2260000000 0 9999 G2GT25

1900 1.000

2265000000 0 9999 G4GT25

1900 1.000

2260000000 0 1 G2H3 G2H31 G2H3C1 G2H32 G4H31 G2H3C2 G4H32

1900 1.000 0.0000 0.0000 0.000 0.000 0.000 0.0001996 0.500 0.4950 0.0050 0.000 0.000 0.000 0.0001997 0.000 0.9900 0.0100 0.000 0.000 0.000 0.0002002 0.000 0.7425 0.0075 0.000 0.000 0.250 0.0002003 0.000 0.4950 0.0050 0.000 0.000 0.500 0.0002004 0.000 0.2475 0.0025 0.000 0.000 0.750 0.0002005 0.000 0.0000 0.0000 0.000 0.000 1.000 0.0002006 0.000 0.0000 0.0000 0.000 0.000 1.000 0.000

2260000000 1 3 G2H4 G2H4C G4H4 G2H41 G2H4C1 G4H41 G2H42 G2H4C2 G4H42

1900 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.500 0.000 0.000 0.495 0.005 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.990 0.010 0.000 0.000 0.000 0.0002002 0.000 0.000 0.000 0.675 0.075 0.000 0.000 0.200 0.0502003 0.000 0.000 0.000 0.450 0.050 0.000 0.000 0.400 0.1002004 0.000 0.000 0.000 0.225 0.025 0.000 0.000 0.600 0.1502005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.800 0.2002006 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.800 0.200

2260000000 3 6 G2H5 G2H5C G2H51 G2H5C1 G2H52 G2H5C2

1900 1.000 0.000 0.0000 0.0000 0.000 0.0001996 0.500 0.000 0.4950 0.0050 0.000 0.0001997 0.000 0.000 0.9900 0.0100 0.000 0.0002002 0.000 0.000 0.9900 0.0100 0.000 0.0002003 0.000 0.000 0.9900 0.0100 0.000 0.0002004 0.000 0.000 0.7425 0.0075 0.250 0.0002005 0.000 0.000 0.4950 0.0050 0.500 0.0002006 0.000 0.000 0.2475 0.0025 0.750 0.0002007 0.000 0.000 0.0000 0.0000 1.000 0.0002008 0.000 0.000 0.0000 0.0000 1.000 0.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B11

2260000000 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.005 0.018 0.977 0.000 0.000 0.000 0.000 0.000 0.0001996 0.003 0.009 0.488 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.017 0.983 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.008 0.492 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.006 0.369 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.004 0.246 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.002 0.123 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265000000 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.180 0.069 0.751 0.000 0.000 0.000 0.000 0.000 0.0001996 0.090 0.035 0.375 0.000 0.083 0.417 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.167 0.833 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265000000 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.005 0.018 0.977 0.000 0.000 0.000 0.000 0.000 0.0001996 0.003 0.009 0.488 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.017 0.983 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.008 0.492 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.006 0.369 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.004 0.246 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.002 0.123 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2260001010 0 9999 R12S

1900 1.000

2265001010 0 9999 R14S

1900 1.000

2260001020 0 9999 R12S

1900 1.000

2265001020 0 9999 R14S

1900 1.000

2260001030 0 9999 R12S

1900 1.000

2265001030 0 9999 R14S

1900 1.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B12

2265004010 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.050 0.070 0.880 0.000 0.000 0.000 0.000 0.000 0.0001996 0.025 0.035 0.440 0.000 0.052 0.448 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.104 0.896 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004011 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.150 0.060 0.790 0.000 0.000 0.000 0.000 0.000 0.0001996 0.075 0.030 0.395 0.000 0.072 0.429 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.143 0.857 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004015 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.005 0.495 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.010 0.990 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2260004020 6 9999 G2H5 G2H5C G2H51 G2H5C1 G2H52 G2H5C2

1900 1.000 0.000 0.0000 0.0000 0.000 0.0001996 0.500 0.000 0.4950 0.0050 0.000 0.0001997 0.000 0.000 0.9900 0.0100 0.000 0.0002002 0.000 0.000 0.9900 0.0100 0.000 0.0002003 0.000 0.000 0.9900 0.0100 0.000 0.0002004 0.000 0.000 0.7425 0.0075 0.250 0.0002005 0.000 0.000 0.4950 0.0050 0.500 0.0002006 0.000 0.000 0.2475 0.0025 0.750 0.0002007 0.000 0.000 0.0000 0.0000 1.000 0.0002008 0.000 0.000 0.0000 0.0000 1.000 0.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B13

2260004021 6 9999 G2H5 G2H5C G2H51 G2H5C1 G2H52 G2H5C2

1900 1.000 0.000 0.0000 0.0000 0.000 0.0001996 0.500 0.000 0.4950 0.0050 0.000 0.0001997 0.000 0.000 0.9900 0.0100 0.000 0.0002002 0.000 0.000 0.9900 0.0100 0.000 0.0002003 0.000 0.000 0.9900 0.0100 0.000 0.0002004 0.000 0.000 0.7425 0.0075 0.250 0.0002005 0.000 0.000 0.4950 0.0050 0.500 0.0002006 0.000 0.000 0.2475 0.0025 0.750 0.0002007 0.000 0.000 0.0000 0.0000 1.000 0.0002008 0.000 0.000 0.0000 0.0000 1.000 0.000

2260004025 0 1 G2H3 G2H31 G2H3C1 G2H32 G4H31 G2H3C2 G4H32

1900 1.000 0.0000 0.0000 0.000 0.000 0.000 0.0001996 0.500 0.4950 0.0050 0.000 0.000 0.000 0.0001997 0.000 0.9900 0.0100 0.000 0.000 0.000 0.0002002 0.000 0.7425 0.0075 0.000 0.000 0.250 0.0002003 0.000 0.4950 0.0050 0.000 0.000 0.500 0.0002004 0.000 0.2475 0.0025 0.000 0.000 0.750 0.0002005 0.000 0.0000 0.0000 0.000 0.000 1.000 0.0002006 0.000 0.0000 0.0000 0.000 0.000 1.000 0.000

2260004025 1 3 G2H4 G2H4C G4H4 G2H41 G2H4C1 G4H41 G2H42 G2H4C2 G4H42

1900 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.500 0.000 0.000 0.490 0.005 0.005 0.000 0.000 0.0001997 0.000 0.000 0.000 0.980 0.010 0.010 0.000 0.000 0.0001998 0.000 0.000 0.000 0.972 0.010 0.018 0.000 0.000 0.0002002 0.000 0.000 0.000 0.675 0.075 0.000 0.000 0.200 0.0502003 0.000 0.000 0.000 0.450 0.050 0.000 0.000 0.400 0.1002004 0.000 0.000 0.000 0.225 0.025 0.000 0.000 0.600 0.1502005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.800 0.2002006 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.800 0.200
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B14

2265004025 3 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.063 0.936 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.032 0.468 0.000 0.037 0.463 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.073 0.927 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004025 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.000 0.500 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.000 0.375 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.000 0.250 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2260004026 0 1 G2H3 G2H31 G2H3C1 G2H32 G4H31 G2H3C2 G4H32

1900 1.000 0.0000 0.0000 0.000 0.000 0.000 0.0001996 0.500 0.4950 0.0050 0.000 0.000 0.000 0.0001997 0.000 0.9900 0.0100 0.000 0.000 0.000 0.0002002 0.000 0.7425 0.0075 0.000 0.000 0.250 0.0002003 0.000 0.4950 0.0050 0.000 0.000 0.500 0.0002004 0.000 0.2475 0.0025 0.000 0.000 0.750 0.0002005 0.000 0.0000 0.0000 0.000 0.000 1.000 0.0002006 0.000 0.0000 0.0000 0.000 0.000 1.000 0.000

2260004026 1 3 G2H4 G2H4C G4H4 G2H41 G2H4C1 G4H41 G2H42 G2H4C2 G4H42

1900 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.500 0.000 0.000 0.490 0.005 0.005 0.000 0.000 0.0001997 0.000 0.000 0.000 0.980 0.010 0.010 0.000 0.000 0.0001998 0.000 0.000 0.000 0.972 0.010 0.018 0.000 0.000 0.0002002 0.000 0.000 0.000 0.675 0.075 0.000 0.000 0.200 0.0502003 0.000 0.000 0.000 0.450 0.050 0.000 0.000 0.400 0.1002004 0.000 0.000 0.000 0.225 0.025 0.000 0.000 0.600 0.1502005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.800 0.2002006 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.800 0.200
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B15

2265004026 3 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.063 0.936 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.032 0.468 0.000 0.037 0.463 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.073 0.927 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004026 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.000 0.500 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.000 0.375 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.000 0.250 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265004030 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.010 0.990 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.005 0.495 0.000 0.010 0.490 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.019 0.981 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004030 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.002 0.998 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.001 0.499 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.000 0.375 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.000 0.250 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265004031 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.010 0.990 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.005 0.495 0.000 0.010 0.490 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.019 0.981 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B16

2265004031 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.002 0.998 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.001 0.499 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.000 0.375 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.000 0.250 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2260004035 0 25 G2GT25

1900 1.000

2260004036 0 25 G2GT25

1900 1.000

2265004035 0 25 G4GT25

1900 1.000

2265004036 0 25 G4GT25

1900 1.000

2265004040 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.005 0.495 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.010 0.990 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004040 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.164 0.836 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.082 0.418 0.082 0.418 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.164 0.836 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.082 0.418 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.062 0.313 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.041 0.209 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.020 0.105 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B17

2265004041 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.005 0.495 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.010 0.990 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004041 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.164 0.836 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.082 0.418 0.082 0.418 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.164 0.836 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.082 0.418 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.062 0.313 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.041 0.209 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.020 0.105 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265004055 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.027 0.973 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.013 0.487 0.000 0.018 0.481 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.037 0.963 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004055 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.007 0.993 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.003 0.497 0.003 0.497 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.007 0.993 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.003 0.497 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.002 0.373 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.001 0.249 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265004056 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.027 0.973 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.013 0.487 0.000 0.018 0.481 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.037 0.963 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B18

2265004056 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.007 0.993 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.003 0.497 0.003 0.497 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.007 0.993 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.003 0.497 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.002 0.373 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.001 0.249 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265004071 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.086 0.349 0.565 0.000 0.000 0.000 0.000 0.000 0.0001996 0.043 0.175 0.282 0.000 0.199 0.301 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.398 0.602 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265004071 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.413 0.587 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.207 0.293 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.413 0.587 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.206 0.294 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.155 0.220 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.104 0.146 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.052 0.073 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265005040 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.000 0.500 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.000 0.375 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.000 0.250 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.000 0.125 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B19

2265006005 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.006 0.020 0.974 0.000 0.000 0.000 0.000 0.000 0.0001996 0.003 0.010 0.487 0.000 0.016 0.484 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.032 0.968 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265006005 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.078 0.922 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.039 0.461 0.039 0.461 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.078 0.922 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.039 0.461 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.030 0.345 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.020 0.230 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.010 0.115 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000

2265006010 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.000 0.500 0.000 0.005 0.495 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.010 0.990 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2265006010 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.000 0.143 0.857 0.000 0.000 0.000 0.000 0.000 0.0001996 0.000 0.072 0.428 0.072 0.428 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.143 0.857 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.071 0.429 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.053 0.322 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.035 0.215 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.017 0.108 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B20

2260007005 6 9999 G2H5 G2H5C G2H51 G2H5C1 G2H52 G2H5C2

1900 1.000 0.000 0.0000 0.0000 0.000 0.0001996 0.500 0.000 0.4950 0.0050 0.000 0.0001997 0.000 0.000 0.9900 0.0100 0.000 0.0002002 0.000 0.000 0.9900 0.0100 0.000 0.0002003 0.000 0.000 0.9900 0.0100 0.000 0.0002004 0.000 0.000 0.7425 0.0075 0.250 0.0002005 0.000 0.000 0.4950 0.0050 0.500 0.0002006 0.000 0.000 0.2475 0.0025 0.750 0.0002007 0.000 0.000 0.0000 0.0000 1.000 0.0002008 0.000 0.000 0.0000 0.0000 1.000 0.000

2265010010 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.180 0.069 0.751 0.000 0.000 0.000 0.000 0.000 0.0001996 0.090 0.035 0.375 0.000 0.083 0.417 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.167 0.833 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2267000000 25 9999 LGT25

1900 1.000

2268000000 25 9999 NGT25

1900 1.000 0.000 0.000

2285004015 0 6 G2N1 G4N1O G4N1S G2N11 G4N1O1 G4N1S1 G4N1SC1 G4N1O2 G4N1S2

1900 0.180 0.069 0.751 0.000 0.000 0.000 0.000 0.000 0.0001996 0.090 0.035 0.375 0.000 0.083 0.417 0.000 0.000 0.0001997 0.000 0.000 0.000 0.000 0.167 0.833 0.000 0.000 0.0002007 0.000 0.000 0.000 0.000 0.097 0.486 0.000 0.417 0.0002008 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000

2285004015 6 25 G2N2 G4N2O G4N2S G4N2O1 G4N2S1 G4N2O2 G4N2S2 L4N2 N4N2

1900 0.005 0.018 0.977 0.000 0.000 0.000 0.000 0.000 0.0001996 0.003 0.009 0.488 0.000 0.500 0.000 0.000 0.000 0.0001997 0.000 0.000 0.000 0.017 0.983 0.000 0.000 0.000 0.0002001 0.000 0.000 0.000 0.008 0.492 0.500 0.000 0.000 0.0002002 0.000 0.000 0.000 0.006 0.369 0.625 0.000 0.000 0.0002003 0.000 0.000 0.000 0.004 0.246 0.750 0.000 0.000 0.0002004 0.000 0.000 0.000 0.002 0.123 0.875 0.000 0.000 0.0002005 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
Table B17. Nonroad SI Technology Distributions by SCC and HP Category (except Recreational Marine)*

Year SCC HPmn HPmx Fraction of Population in Each Technology Type

NR-010c.wpd B21

2285004015 25 9999 G4GT25

1900 1.000

2285006015 25 9999 LGT25

1900 1.000

2285008015 25 9999 NGT25

1900 1.000

* Taken from tech.dat input file.