State of California  
Air Resources Board  
 
Public Hearing to Consider Proposed 
Amendments to the Small Off -Road Engine 
Regulations: Transition to Zero Emissions  
 
Staff Report: Initial Statement o f Reasons  
 
Date o f Release: October  12, 2021  
Scheduled f or Consideration : December  9, 2021  
 
 
 
 
 
This report has been reviewed by the staff of the California Air Resources Board and 
approv ed for publication. Approval does not signify that the contents necessarily 
reflect the views and policies of the California Air Resources Board, nor does mention 
of trade names or commercial products constitute endorsement or recommendation for use.     
This Page Intentionally Left Blank   
i Table  of Contents  
Table of Contents  ..................................................................................................... i  
List of Appendices  .................................................................................................. iv  
List of Figures  ......................................................................................................... v  
List of Tables  .......................................................................................................... vi 
Acronyms  ............................................................................................................... ix  
Units of Measure  .................................................................................................. xiii  
Executive Summary  .................................................................................................  1 
A. Authority to Regulate SORE  .......................................................................... 2  
B. Purpose of Proposed Amendments  ............................................................... 2  
C. Summary of Proposed Amendments  ............................................................. 3  
D. Air Quality and Public Health Benefits  ........................................................... 5  
E. Economic Impacts  .......................................................................................... 6  
F. Technological Feasibility  ................................................................................ 7  
G. Environmental Analysis .................................................................................. 8  
H. Environmental Justice  .................................................................................... 9  
I. Regulat ory Alternatives Evaluated  ................................................................. 9  
J. Regulatory Development Process and Outreach Efforts  ............................. 10 
K. Justification for Regulations Different from Federal Regulations  ................ 11 
L. Staff Recommendation  ................................................................................ 11 
I. Introduction and Background ............................................................................ 1  
A. Overview  ........................................................................................................ 1  
B. Legal Authority and Responsibilities .............................................................. 4  
C. Regulatory History  ......................................................................................... 5  
D. Criteria Air Pollutants and Air Quality Commitments  .................................... 7  
E. Technological Feasibility  .............................................................................. 11 
F. Additional Strategies for Transition to ZEE  ................................................. 26 
II. The Problem That the Proposal Is Intended to Address  .................................. 27 
A. Current SORE Regulations Will Not Achieve Required Emission 
Reductions  ................................................................................................... 27 
B. Exhaust Emissions Durability Periods for SORE Do Not Represent Actual Lifetimes  ........................................................................................... 40
 
C. Trading of Evaporative Emission Credits Is Not Permitted, Restricting Manuf acturer Flexibility  ............................................................. 43
 
D. Fuel Caps and Tethers Can Cause Fuel to Spill  ........................................... 44 
E. The Variance Provisions Cause Inequitable Results, Leading to Potential Unmitigated Excess Emissions ...................................................... 45
  
ii F. Tilting Equipment for Cleaning and Maintenance Can Result in 
Excess Emissions  .......................................................................................... 46 
G. Manufacturers May Not Determine Fuel Tank Pressure Limits 
Accurately  .................................................................................................... 48 
H. Manufacturers Wish to Accelerate Preconditioning  .................................... 48 
I. CARB Test Procedures Have Become Inconsistent with U.S. EPA 
Test Procedures  ........................................................................................... 49 
J. Compliance Testing of Exhaust Emissions from Engines is Overly Burdensome  ................................................................................................. 50
 
K. Other Changes to the Regulations and Procedures  .................................... 51 
III. Air Quality  ...................................................................................................... 51 
A. SORE Emission Inventory and Modeling Methodology ............................... 51 
B. Emission Reductions in Support of the 2016 State SIP Strategy  ................. 57 
IV. Benefits Anticipated from the Regulatory Action, Including the Benefits or 
Goals Provided in the Authorizing Statute  ...................................................... 61 
A. Emission Benefits  ......................................................................................... 62 
B. Benefits to Typical Businesses  ..................................................................... 68 
C. Benefits to Small Businesses  ........................................................................ 69 
D. Benefits to Individuals  .................................................................................. 69 
E. Other Benefits .............................................................................................. 82 
V. Environmental Analysis  ................................................................................... 83 
A. Introduction  ................................................................................................. 83 
B. Prior Environmental Analysis  ....................................................................... 84 
C. The Proposed Amendments  ........................................................................ 88 
D. Com parison of the Proposed Amendments to the SORE SIP 
Strategy ....................................................................................................... 89 
E. Analysis ........................................................................................................ 90 
VI. Environmental Justice  ..................................................................................... 95 
VII. Standardized Regulatory Impact Analysis  ....................................................... 97 
A. Changes Since Originally -submitted SRIA  ................................................... 98 
B. Discussion of Macroeconomic Modeling Results  ....................................... 109  
VIII.   Evaluation of Regulatory Alternatives  .......................................................... 115  
A. Alternative 1  .............................................................................................. 117  
B. Alternative 2  .............................................................................................. 125  
C. Small Business Alternative ......................................................................... 135  
D. Performance Standards in Place of Prescriptive Standards  ....................... 143  
E. Health and Safety Code Section 57005 Major Regulation 
Alternatives  ................................................................................................ 143   
iii IX. Justification for Adoption of Regulations Different from Federal Regulations 
Contained in the Code of Federal Regulations  .............................................. 143  
X. Public Process for Development of the Proposed Action (Pre -Regulatory 
Information) .................................................................................................. 148  
A. Survey Development and Informational Update to the Board  .................. 148  
B. Public Workshops  ...................................................................................... 150  
C. Solicitation of Alternatives  ......................................................................... 151  
D. Stakeholder Meetings  ................................................................................ 151  
E. Stakeholder Outreac h ................................................................................ 152  
XI. The Specific Purpose and Rationale of Each Adoption, Amendment, or Repeal  ........................................................................................................... 153
 
A. Exhaust Emission Regulations  .................................................................... 154  
B. Evaporative Emission Regulations  ............................................................. 209  
C. TP-901, Test Procedure for Determining Permeation Emissions 
from Small Off -Road Engine Fuel Tanks  .................................................... 251  
D. TP-902, Test Procedure for Determining Diurnal Emissions from 
Small Off -Road Engines  ............................................................................. 267  
E. CP-902, Certification Procedure for Evaporative Emission Control 
Systems on Small Off -Road Engines  .......................................................... 287  
F. California Exhaust Emission Standards and Test Procedures for 
New 2013 and Later Small Off -Road Engines; Engine- Testing 
Procedures (Part 1054)  .............................................................................. 294  
G. California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine- Testing 
Procedures (Part 1065)  .............................................................................. 332
 
XII. References  .................................................................................................... 4 10 
XIII.  Appendices ................................................................................................... 438  
 
 
   
iv List o f Appendices  
A. Proposed Amendments to the Small Off -Road Engine Exhaust Emission 
Regulations, California Code of Regulations, Title 13, Division 3, Chapter 9. 
Off-Road Vehicles and Engines Pollution Control Devices, Article 1. Small Off -Road 
Engines  
B. Prop osed Amendments to the Small Off -Road Engine Evaporative Emission 
Regulations, California Code of Regulations, Title 13, Division 3, Chapter 15. Additional Off -Road Vehicles and Engines Pollution Control Requirements, 
Article  1. Evaporative Emission Requirements for Off -Road Equipment  
C. Proposed Amendments to Small Off -Road Engine Evaporative Emissions Test 
Procedure, TP -901, Test Procedure for Determining Permeation Emissions from 
Small Off -Road Engine Fuel Tanks  
D. Proposed Amendments to Small Off -Road E ngine Evaporative Emissions Test 
Procedure, TP -902, Test Procedure for Determining Evaporative Emissions from 
Small Off -Road Engines  
E. Proposed Amendments to Small Off -Road Engine Evaporative Emission Control 
System Certification Procedure, CP -902, Certification Procedure for Evaporative 
Emission Control Systems on Small Off -Road Engines  
F. Proposed Amendments to the California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines ; Engine -Testing 
Procedures (Part 1054)  
G. Proposed Amendments to the California Exhaust Emission Standards and Test 
Procedures for New 2013 and Later Small Off -Road Engines ; Engine -Testing 
Procedures (Part 1065)  
H. Final Environmental Analysis for the Revised Proposed 2016 State Strateg y for the 
State Implementation Plan  
I. Standardized Regulatory Impact Assessment  with Department of Finance  
Comments  
J. Pre-Rulemaking Workshop Notices and Email Soliciting Alternatives  
 
 
  
v List o f Figures  
Figure ES- 1. Summer average NO x + ROG emissions from small off -road engines 
and light -duty passenger cars in California without further regulation.  . 3 
Figure ES- 2. Summer average NO x + ROG emissions under the Baseline Scenario 
and the Proposed Amendments.  ............................................................ 6  
Figure II -1. Summer average NO x and ROG emissions under current SORE 
regulations.  ........................................................................................... 29 
Figure II -2. Evaporative emission compliance testing results for MYs 2015- 2019.  . 30 
Figure II -3. Modeled small off -road equipment population statewide under t he 
Proposed Amendments.  ....................................................................... 32 
Figure II -4. A hydraulic jack being used to clean under a riding lawn mower.  ....... 47 
Figure III- 1. Modeled small off -road equipment population statewide under the 
Baseline Scenario.  ................................................................................. 54 
Figure III- 2. Summer average NO x emissions under the Proposed Amendments and 
the Baseline Scenario.  ........................................................................... 60 
Figure III- 3. Summer average ROG  emissions under the Proposed Amendments and 
the Baseline Scenario.  ........................................................................... 60 
Figure IV -1. Annual average NO x emissions under the Proposed Amendments and 
the Baseline Scenario.  ........................................................................... 65 
Figure IV -2. Annual average ROG emissions under the Proposed Amendments and 
the Baseline Scenario.  ........................................................................... 65 
Figure VII -1. Statewide Costs, cost -savings, and overall net costs under the 
Proposed Amendments.  ..................................................................... 101  
Figure VIII- 1. Modeled small off -road equipment population statewide under 
Alternative 1.  ...................................................................................... 118  
Figure VIII- 2. Statewide costs, cost -savings, and overall net costs under Alternative  1.
 ............................................................................................................ 120  
Figure VIII- 3. Annual average NOx emissions under Alternative 1 and the Baseline Scenario.  ............................................................................................. 123
 
Figure VIII- 4. Annual average ROG emissions under Alternative 1 and the Baseline Scenario.  ............................................................................................. 123
 
Figure VIII- 5. Modeled small off -road equipment population statewide under 
Alternative 2.  ...................................................................................... 128  
Figure VIII- 6. Statewide costs, cost -savings, and overall net costs under Alternative 2.
 ............................................................................................................ 131  
Figure VIII- 7. Annual average NOx emissions under Alternative 2 and the Baseline Scenario.  ............................................................................................. 133
 
Figure VIII- 8. Annual average ROG emissions under Alternative 2 and the Baseline 
Scenario.  ............................................................................................. 133   
vi Figure VIII- 9. Modeled small off -road equipment population statewide under the 
Small Business Alternative.  ................................................................. 136  
Figure VIII -10. Statewide costs, cost -savings, and overall net costs under the Small 
Business Alternative.  ........................................................................... 139  
Figure VIII- 11. Annual average NOx emissions under the Small Business Alternative 
and the Baseline Scenario.  .................................................................. 141  
Figure VIII- 12. Annual average ROG emissions under the Small Business Alternative 
and the Baseline Scenario.  .................................................................. 141  
 
List o f Tables  
Table ES -1. Results of the economic analyses for the Proposed Amendments over the regulatory horizon of 2023 through 2043 (billions 2019$).  ................. 7
 
Table I -1. Current SORE exhaust emission standards.  .............................................. 6  
Table I -2. Current SORE diurnal emission standards.  ................................................ 7  
Table I -3. Current permeation emission standards for SORE with displacement less than or equal to 80 cc.  ........................................................................ 7
 
Table I -4. Residential SORE equipment and ZEE used in performance analysis.  .... 15 
Table I -5. Professional SORE equipment and ZEE used in performance analysis.  .. 17 
Table I -6. Residential SORE equipment and ZEE limited warranty periods.  ........... 20 
Table I -7. Professional SORE equipment and ZEE limited warranty periods.  ......... 21 
Table II- 1. Current SORE exhaust emission standards and exhaust emission 
standards under the Proposed Amendments.  ........................................ 34 
Table II- 2. Current SORE evaporative emission standards and evaporative emission 
standards under the Proposed Amendments.  ........................................ 35 
Table II- 3. Current SORE emissions durability periods and emissions durability periods f or generator engines under the Proposed Amendments.  ........ 43
 
Table II- 4. Current SORE emissions durability periods and emissions durability  
periods for SORE other than generator engines under the Proposed Amendments.  .......................................................................................... 43
 
Table III- 1. Median equipment age from the CSUF survey.  ...................................... 54 
Table III- 2. Exhaust emission standards and modeled emission levels for 
MY 2024- 2027 generators assuming complete use of banked credits 
under the Proposed Amendments.  ......................................................... 56 
Table III- 3. Evaporative emission standards and modeled emission levels for MY 
2024- 2027 generators assuming complete use of banked credits under 
the Proposed Amendments.  ................................................................... 56  
vii Table III- 4. Summer average emission reduc tions under the Proposed   
Amendments.  .......................................................................................... 59 
Table III- 5. Comparison of summer average emission reductions under the Proposed 
Amendments to 2016 State SIP Strategy expected emissions for SORE 
for the San Joaquin Valley and South Coast air basins.  .......................... 61 
Table IV -1. Annual average emission reductions under the Proposed  Amendments.  .......................................................................................... 64
 
Table IV -2. MY 2024- 2027 generator exhaust emission standards and emission rates 
under the Proposed Amendments with twice the amount of banked emission credits that manufacturers held at the end of MY  2018.  .......... 66
 
Table IV -3. MY 2024- 2027 generator evaporative emission standards and emission 
rates under the Proposed Amendments with twice the amount of banked 
emission credits that manufacturers held at the end of MY  2018.  .......... 67 
Table IV -4. Modeled regional and statewide avoided mortality and morbidity 
incidents from 2023 through 2043 under the Proposed Amendments, central estimates and 95
 percent confidence intervals.  ........................... 72 
Table IV -5. Annual statewide avoided mortality and morbidity incidents under the Proposed Amendments, central estimates and 95 percent confidence 
intervals.  .................................................................................................. 73
 
Table IV -6. Valuation per incident for avoided health outcomes (2019$). ................. 77 
Table IV -7. Annual valuation of avoided health outcomes under the Proposed Amendments (million 2019$).  .................................................................. 78
 
Table IV -8. Statewide valuation from avoided health outcomes under the Proposed 
Amendments.  .......................................................................................... 79 
Table IV -9. Social cost of carbon 2020- 2040 (2007$ per metric ton).  ....................... 80 
Table IV -10. Avoided social cost of carbon under the Proposed Amendments (million 2019$).  ........................................................................................ 81
 
Table VII -1. Modeled costs to professional and residential users per year under the Proposed Amendments relative to the Baseline Scenario  
(million 2019$).  ...................................................................................... 100
 
Table VII -2. Modeled costs to professional users (businesses, landscapers and 
government entities) per year under the Proposed Amendments relative 
to the Baseline Scenario (million 2019$). ............................................... 102  
Table VII -3. Modeled costs to residential users per year under the Proposed Amendments relative to the Baseline Scenario (million 2019$).  ........... 103
 
Table VII -4. Upfront and annual ongoing costs for professional -grade SORE and ZEE, 
at 2023 prices.  ....................................................................................... 104  
Table VII -5. Upfront and annual ongoing costs for residential users of small off -road 
equipment.  ............................................................................................ 106  
Table VII -6. Cost-benefit analysis of the Proposed Amendments (billion 2019$).  ... 108   
viii Table VII -7. California employment impacts under the Proposed Amendments.  .... 110  
Table VI I-8. Job impacts by primary and secondary industries under the Proposed 
Amendments.  ........................................................................................ 111  
Table VII -9. Change in California output growth by industry under the Proposed Amendments.  ........................................................................................ 113
 
Table VII -10. Change in gross domestic private investment growth under the 
Proposed  Amendments.  ........................................................................ 115  
Table VIII- 1. Cost-benefit comparison of the Proposed Amendments and 
regulatory alternatives (billion 2019$).  .................................................. 116  
Table VIII- 2. Modeled costs to professional and residential users per year under 
Alternative 1 relative to the Baseline Scenario  (millions 2019$).  ........... 119  
Table VIII- 3. Annual average emission reductions under Alternative 1.  .................... 122  
Table VIII- 4. Statewide valuation from avoided health outcomes under  
Alternative  1. ......................................................................................... 124  
Table VIII- 5. Cost-benefit comparison of the Proposed Amendments and  
Alternative 1 (billion  2019$).  .................................................................. 124  
Table VIII- 6. MYs 2024- 2025 SORE exhaust emission standards and emission levels 
assuming complete use of banked credits under Alternative 2.  ........... 126  
Table VIII- 7. MYs 2026- 2029 exhaust emission standards under Alternative 2.  ........ 126  
Table VIII- 8. MYs 2024- 2025 SORE evaporative emission standards and emission 
levels assuming complete use of banked credits under Alternative 2.  . 127  
Table VIII- 9. MYs 2026- 2029 evaporative emission standards and emission levels 
under Alternative 2.  ............................................................................... 127  
Table VIII- 10. Modeled  costs to professional and residential users per year under 
Alternative 2 relative to the Baseline Scenario (millions 2019$).  ........... 130  
Table VIII- 11. Annual average emission reductions under Alternative 2.  .................... 132  
Table VIII- 12. Statewide valuation from avoided health outcomes under  
Alternative 2 . ......................................................................................... 134  
Table VIII- 13. Cost-benefit comparison of the Proposed Amendments and  
Alternative 2 (billion  2019 $). .................................................................. 134  
Table VIII- 14. Modeled costs to professional and residential users per year under  the 
Small Business Alternative relative to the Baseline Scenario ( millions 
2019$).  ................................................................................................... 138  
Table VIII- 15. Annual average emission reductions under  the Small Business 
Alternative . ............................................................................................ 140  
Table VIII- 16. Statewide valuation from avoided health outcomes under the Small Business Alternative. .............................................................................. 142
 
Table VIII- 17. Cost-benefit comparison of the Proposed Amendments and the Small 
Business Alternative (billion  2019$).  ...................................................... 142   
ix Table IX- 1. Current SORE exhaust emission standards and exhaust emission 
standards under the Proposed Amendments.  ...................................... 145  
Table IX- 2. Current SORE evaporative emission standards and evaporative emission standards under the Proposed Amendments.  ...................................... 145
 
Table IX- 3. Current SORE exhaust CO emission standards and exhaust CO emission 
standards under the Proposed Amendments.  ...................................... 146  
 
Acronyms  
ABT – Averaging, Banking, and Trading  
AGZA – American Green Zone Alliance  
ANSI – American National Standards Institute 
ARB – California Air Resources Board  
ASTM – ASTM International  
BAAQMD – Bay Area Air Quality Management District 
Board – California Air Resources Board  
CARB – California Air Resources Board  
CCR – California Code of Regulations  
CEQA – California Environmental Quality Act 
CFR – Code of Federal Regulations  
CH 4 – Methane  
CIPM  MRA  – Mutual Recognition Arrangement  of the Comité International des Poids 
et Mesures  
CNG – Compressed natural gas  
CO – Carbon monoxide  
CO 2 – Carbon dioxide  
CO 2e – Carbon dioxide equivalents  
CORE – Clean Off -Road Equipment Voucher Incent ive Project  
x COVID -19 – Coronavirus Disease 2019  
CP – Certification Procedure  
CSUF – California State University, Fullerton  
CSUF SSRC – California State University, Fullerton Social Science Research Center  
CVS – Constant volume sampling system  
DEF – Diesel exhaust f luid 
DF – Deterioration factor  
DOF – California Department of Finance  
EA – Environmental Analysis 
EFELD – Evaporative Family Emission Limit Differential  
EIR – Environmental Impact Report  
EMA – Truck and Engine Manufacturers Association  
EMEL – Evaporative Model Emission Limit  
EO – Executive Order 
ER – Emergency Room  
EVR – Enhanced vapor recovery 
FEL – Family Emission Level  
FID – Flame ionization detector  
FTIR – Fourier transform infrared  
GDF – Gasoline dispensing facility  
GHG – Greenhouse gas 
GPA – Gas Processors Association 
H2O – Water  
HC – Hydrocarbon s 
HSC – Health and Safety Code   
xi IPCC – Intergovernmental Panel on Climate Change  
ISO – International Organization of Standardization  
ISOR – Initial Statement of Reasons (this S taff Report)  
IWG – Interagency Working Group  
LNG – Liquefied natural gas  
LPG – Liquefied petroleum gas  
LSI – Large spark -ignition 
MECA – Manufacturers of Emission Controls Association 
MSS – CARB’s 2020 Mobile Source Strategy  
MY – Model Year  
NAAQS – National Ambient Air Quality Standards  
NASEM – National Academies of Science, Engineering, and Medicine  
NEMA – National Electrical Manufacturers Association  
NGS – National Geodetic Survey  
NIST – National Institute of Standards and Technology  
NMHC  – Nonmethane hydrocarbon  
NMHCE – Nonme thane hydrocarbon equivalent  
NMNEHC – Nonmethane- nonethane hydrocarbon 
NO x – Oxides of n itrogen   
OAL – Office of Administrative Law  
OMB – Office of Management and Budget  
OPEI – Outdoor Power Equipment Institute  
OSHA – Occupational Safety and Health Adminis tration  
PEMS – Portable emission measurement system  
PFC – Portable fuel container   
xii PM – Particulate matter 
PM 2.5 – Particulate matter with  diameter of 2.5 micro meters or less  
PM 10 - Particulate matter with  diameter of 10 micro meters or less  
PRC – Public Resource Code 
PSPS – Public Safety Power Shutoff s 
REMI – Regional Economic Models , Inc. 
RSQE – University of Michigan’s Research Seminar in Quantitative Economics  
ROG – Reactive organic gases 
SAE – SAE International  
SAM – State Administrative Manual  
SBAPCD  – Santa Barbara Air Pollution Control District  
SC-CO 2 – Social cost of carbon  
SCAQMD – South Coast Air Quality Management District 
SHED – Sealed housing for evaporative determination 
SI – Système International  d'Unités  
SIP – State Implementation Plan  
SJVAPCD – San Joaquin Valley Air Pollution Control District  
SORE – Small o ff-road engine s 
SRIA – Standardized Regulatory Impact Analysis or Standardized Regulatory Impact 
Assessment  
TAC – Toxic Air Contaminant 
THC – Total hydrocarbons  
THCE – Total hydrocarbon equivalent  
TP – Test Procedure  
tpd – Tons per day  
TSD – Technical Support Document   
xiii U.S. EPA – United States Environmental Protection Agency  
USB – Universal Serial Bus  
UV – Ultraviolet  
ZEE – Zero-emission equipment  
 
Units of Measure  
° – degrees  
% – percent  
cc – cubic centimeters  
g – grams  
hp – horsepower  
kgal – thousand gallons 
kW – kilowatt  
kWh – thousand Watt hours  
lbs – pounds  
m – meters  
m3 – cubic meters  
µm – micrometers  
µg – micrograms  
MMT  – million metric tons  
ppb – parts per billion  
tpd – tons per day  
   
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ES-1 Executive Summary  
In this rulemaking, the California Air Resources Board (CARB or Board) staff is 
proposing amendments to the Small Off -Road Engine (SORE) Exhaust and Evaporative 
Emission Regulations  and Test Procedures (collectively, Proposed Amendme nts). 
The Proposed Amendments would  accelerat e the transition  of SORE equipment to 
zero- emission equipment (ZEE) . SORE equipment and ZEE are collectively referred to 
as small off -road equipment. Deployment  of ZEE is key to meeting the expected 
emission reductions in the Revised Proposed  2016 State Strategy for the State 
Implementation Plan (2016 State SIP Strategy)  and the goals of Governor Newsom’s 
Executive Order (EO) N -79-20, issued September 23, 2020.  The Proposed 
Amendments would update emission standards for new SORE (engines or equipment produced for sale or lease for use or operation in California)  and would  not affect 
equipment already in use. 
This Executive Summary and the Staff Report comprise the Initial Statement of 
Reasons (ISOR)  for this  proposed rulemaking, required by the California Administrative  
Procedure  Act. Appendi ces A-G contain  the Proposed Amendments:  
• Appendix A: Proposed Amendments to the Small Off -Road Engine Exhaust 
Emission Regulations, California Code of Regulations, Title 13, Division 3, 
Chapter 9. Off -Road Vehicles and Engines Pollution Control Devices, Article 1. 
Small Off -Road Engin es  
• Appendix B: Proposed Amendments to the Small Off -Road Engine Evaporative 
Emission Regulations, California Code of Regulations, Title 13, Division 3, 
Chapter 15. Additional Off -Road Vehicles and Engines Pollution Control 
Requirements, Article 1.  Evapora tive Emission Requirements for Off -Road 
Equipment  
• Appendix C: Proposed Amendments to Small Off - Road Engine Evaporative 
Emissions Test Procedure, TP -901, Test Procedure for Determining Permeation 
Emissions from Small Off -Road Engine Fuel Tanks 
• Appendix D: Proposed Amendments to Small Off -Road Engine Evaporative 
Emissions Test Procedure, TP -902, Test Procedure for Determining Evaporative 
Emissions from Small Off -Road Engines  
• Appendix E: Proposed Amendments to Small Off -Road Engine Evaporative 
Emission Contro l System Certification Procedure, CP -902, Certification 
Procedure for Evaporative Emission Control Systems on Small Off -Road Engines   
ES-2 • Appendix F: Proposed Amendments to the California Exhaust Emission 
Standards and Test Procedures for New 2013 and Later Sma ll Off -Road 
Engines; Engine- Testing Procedures (Part 1054)  
• Appendix G: Proposed Amendments to the California Exhaust Emission Standards and Test Procedures for New 2013 and Later  Small Off -Road 
Engines; Engine- Testing Procedures (Part 1065)  
The proposed changes in Appendi ces A-G are shown in underline to indicate 
additions and strikeout to indicate deletions from the existing regulatory text. 
A. Authority to Regulate SORE  
Section 209(e) of the federal Clean Air Act uniquely grants the State of California th e 
authority to adopt and enforce emission standards and other requirements relating to 
the control of emissions from new nonroad engines or vehicles within the state, which 
includes SORE. California is, effectively, allowed an exemption from federal Clean Air 
Act provisions that otherwise prevent states from setting their own emission standards 
for these nonroad mobile sources. The exemption recognizes California’s long 
standing air pollution challenges and pioneering work to reduce mobile source 
emissions.  Under section 209, subsection (e)(1) of the federal Clean Air Act, “New 
engines which are used in construction equipment or vehicles or used in farm 
equipment or vehicles and which are smaller than 175 horsepower”  are preempt from 
CARB’s emission standard s and only subject to emission standards from the 
U.S. Environmental Protection Agency (U.S. EPA) . 
B. Purpose of Proposed Amendments  
Statewide, more than  28 million Californians live in areas  that exceed the national  
ambient air quality standards  (NAAQS)  for ozone and PM 2.5 (particulate matter with 
diameter of 2.5 micrometers or smaller)  (CARB , 2021a 2). Mobile sources power ed by 
fossil fuels are the largest sources of  emissions that contribute to  formation of these 
pollutants . Under California Health and Safety Code (HSC) section 43013, CARB must  
adopt emission standards for off -road engines “for the control of air contaminants and 
sources of air pollution which [CARB] has found to be necessary, cost effective, and technological ly feasible, to carry out the purposes of [its statutory authority under the 
HSC]  ….” The Proposed Amendments are necessary to meet CARB’s obligation under 
HSC section 43018  to “endeavor to achieve the maximum degree of emission 
reduction possible from vehicular and other mobile sources in order to accomplish the attainment of the state standards at the earliest practicable date .” Replacing sales of  
internal combustion engines  in both on -road and off -road applications with  zero-
emission technology is necessary to attain ambient air quality standards and protect the health and welfare of all California resident s. 
SORE are spark -ignition engines rated at or below 19 kilowatts (25.5 horsepower). 
These engines are used in a variety of small off -road equipment ty pes, including, but 
not limited to, lawn mowers, leaf blowers, chainsaws, pressure washers, air compressors, and portable generators. Equipment powered by SORE are referred to  
ES-3 as SORE equipment. SORE equipment emit both  oxides of nitrogen (NO and  NO 2, 
deno ted NO x) and reactive organic gases (ROG), which contribute to particulate 
matter (PM) and ozone formation. In California, SORE emit more NO x and ROG  than 
light- duty passenger cars, both in summer and annually. As shown in Figure ES- 1, 
without further acti on, SORE will emit 1.8 times the amount of summertime NO x and 
ROG  that California light -duty passenger cars emit in 2031  (CARB, 2020 ). 
Figure ES- 1. Summer average  NO x + ROG  emissions from small off -road engines 
and light -duty passenger cars in California  without further regulation. 
 
The 2016 State SIP Strategy includes a  measure estimated  to reduce  statewide  NO X 
and ROG  emissions from SORE by 4 and 36 tons per day (tpd), respectively,  in 2031.  
The Proposed Amendments would exceed these expected  emission reductions to 
help California attain PM 2.5 and ozone NAAQS . The Proposed Amendments are also 
part of a portfolio of “ Strategies, in coordination with other State agencies, 
U.S. Environmental Protection Agency and local air districts, to achieve 1 00 percent 
zero- emission from off -road vehicles and equipment  operations in the State  by 2035,” 
as directed in EO N-79-20, issued September 23, 2020. 
C. Summary of Proposed Amendments  
The Proposed Amendments would  set SORE emission standards to zero  in two 
phases. First, for model year ( MY) 2024 and all subsequent model years, exhaust 
emission standards would be set to zero (0.00 grams per kilowatt- hour or g·kWh-1), 
except for carbon monoxide ( CO). Evaporative emission  standards would also be set 
to zero ( 0.00 grams per test or g·test-1). The evaporative emission standards would 
include “hot soak” emissions ( represent ing emissions that occur when placing a hot 
engine in storage after use on a hot summer day ) to better evaluate emissions from 
 
ES-4 real-world use of SORE equipment.  These emission standards of  zero would apply for 
engines used in all equipment types produced for sale or lease for operation in 
California, except generators. Generator emission standards would be more stringent 
than the existing emission standards starting in MY 2024 , but would not be zero. The 
second phase would be implemented starting in MY 2028, when the emission standard s for generators would be zero.  
The Proposed Amendments would also amend existing emission reduction credit 
programs  to improve consistency and add flexibility for manufacturers . The exhaust 
emission regulation s include an emission reduction credit averaging, banking, and 
trading  (ABT)  program, where manufacturers can generate  credits with  engines that 
emit belo w the emission standards and use them to produce engines that emit above 
the emission standards . This averaging of emissions gives manufacturers the flexibility  
to certif y those higher -emitting engines. Exhaust emission reduction credits may be 
banked for up to five years, to be used later, or may be traded with other 
manufacturers.  The existing evaporative  emission reduction credit  program only 
includes averaging and banking. In the Proposed Amendments, trading would be  
added to the evaporative credit prog ram. New zero -emission generator credit 
programs would be added to the ABT program s, which would allow manufacturers to 
earn emission reduction  credits for zero- emission generators.  
Other Proposed Amendments to the regulations include sunsetting  the voluntary 
“Blue Sky S eries ” engine requirements  and repealing the variance provisions in the 
evaporative emission regulations.  The Blue Sky Standards were developed to allow 
manufacturers to receive recognition for certifying to lower emission standards, b ut 
CARB has no record of any manufacturer taking advantage of the program for 
engines.  Additionally, the Proposed Amendments to the evaporative emission  test 
procedure s would add further instructions for  a fuel tank pressure test, a new fuel cap 
and tether  test, a tilt test to check for fuel leaks, and instructions for  accelerated 
preconditioning of engines. The Proposed Amendments to TP -901 would ensure fuel 
tank testing configurations were closer  to those of production fuel tanks by requiring 
the hole for  a fuel line and grommet system  to be present in the fuel tanks and 
requiring fuel tanks to be tested with the same production fuel cap throughout testing. Evaporative emission control system  certification procedure CP -902 would  be 
used for  all engines, including those with displacement less than 80 cc , which currently 
use a different certification procedure .  
Most of t he Proposed Amendments to the exhaust emission test procedures are 
intended to align them with updates to the federal test procedures that h ave been 
adopted since CARB adopted its  test procedures. The Proposed Amendments also 
include California- specific changes necessary to maintain the stringency of California 
emission standards, provide consistency with other  California SORE regulations, 
prevent redundant effort and confusion for testers , or provide additional flexibility . For 
example, t he requirements for exhaust emission compliance testing would be changed 
from testing “a reasonable number of engines” to “one or more engines.” Procedure 
text that provides examples based on equipment or fuel types that are not relevant to  
ES-5 SORE , such as locomotives and compression -ignition engines,  would be  removed  to 
prevent confusion. References to National Institute of Standards and Technology 
(NIST)- traceable standards would be  changed to  Système International  d'Unités (SI)-
traceable standards  to allow flexibility for manufacturers around the world to  use other 
recognized international standards while still maintaining the consistency necessary to 
ensure test data accuracy, precision, and comparability to the emission standards .  
D. Air Quality and Public Health Benefits  
CARB ’s 2020 Mobile Source Strategy states that “As research continues to show 
harmful effects from air pollution at increasingly lower levels, achieving the State’s complementary goals, targets and standards will provide much -needed public health 
protection for the millions of Californians that still breathe unhealthy air and will 
reduce exposure in the State’s most highly -impacted and disadvantaged 
communities.” An important strategy to reduce emissions  and provide much -needed 
public health protection for Califo rnians  is electrification  of SORE. The small off -road 
equipment  market is well prepared for electrification. The Proposed Amendments 
would  support the goals of the 2016  State SIP Strategy and would reduce emissions of 
pollutants with multiple known adverse health effects  and which are associated with 
existing California a mbient air quality standards . These pollutants include NO
x, which 
contributes to  formation of tropospheric ozone, and PM 2.5, which may deposit deep 
inside the lung s. Long -term exposure to P M2.5 has been causally linked to premature 
death, particularly in people who have chronic heart or lung diseases, and reduced 
lung function in children. The Proposed Amendments would also reduce greenhouse 
gas (GHG) emissions and petroleum use.  
Under the Proposed Amendments, s ignificant reductions in both NO x and ROG  
emissions would begin in calendar year 2025 , years  before emission standards of zero 
would be implemented for generators . In 2031, the expected summer average 
emission reductions woul d be 7.9 tpd of NO x and 64.5 tpd of ROG (Figure ES- 2). 
These represent 43  percent and 51 percent reductions of NO x and ROG , respectively, 
compared to the emissions under the Baseline Scenario . For the purposes of this 
rulemaking, the Baseline Scenario  is defined  as the scenario where existing regulations 
continue and where no further regulatory action is taken on SORE  in the future. The 
Proposed Amendments would result in  total emission reductions of approximately 
59,307 tons of NO x and 423,240 tons of ROG , averaged across the year  from 2023 
through  2043, compared to  the Baseline  Scenario . Such emission  reduction s would 
decrease the amount of adverse health  impacts in California. Through  2043, 
premature deaths  due to cardiopulmonary causes would be  expe cted to decrease by 
892; emergency room (ER) visits for asthma  would be expected  to decrease by 438 ; 
and acute respiratory and cardiovascular hospitalizations would be expected  to 
decrease by 169 and 142, respectively.   
ES-6 Figure ES- 2. Summer average NO x + RO G emissions under the Baseline Scenario  
and the Proposed Amendments. 
 
The Proposed Amendments would decrease  the use of fossil fuels in California, which 
would decrease carbon dioxide and other GHG  emissions. The benefit of the GHG  
emission reductions can  be estimated using the Social Cost of Carbon, which 
calculates benefits between $339 million and $1.43 billion through 2043, depending 
on the discount rate. 
E. Economic Impacts  
Staff conducted economic analyses , including a Standardized Regulatory Impact 
Analysis, for the Proposed Amendments. This included the determin ation  of costs to 
users of small off -road equipment from initial purchase through the useful  lifetime of 
the equipment. Upfront purchase costs could be higher or lower for ZEE than for 
equivalent SORE equipment, depending on the equipment type. In contrast, 
operating costs for ZEE are typically lower than for SORE equipment, due to savings 
on gasoline purchases and reduced maintenance costs.  
Overall, the Proposed Amendments would  have a net  direct cost of $ 4.08 billion 
accrued  over the modeled regulatory horizon  of 2023 through 2043. Resident ial users 
are expected to experience a net direct cost accrued  through 2043 of $2. 79 billion, 
while professional users (nonlandscaping businesses, landscapers and government 
entities) are expected to experience a n accrued  net direct cost of $1.29 billion. When 
health benefits are considered, the Proposed Amendments are estimated to have a 
net benefit of $4. 27 billion accrued through 2043. Overall, the Proposed Amendments 
would have a benefit -cost ratio of 1. 30, meaning the monetized benefits are greater 
 
ES-7 than the costs. Table ES- 1 summarizes the results of the economic analyses for the 
Proposed Amendments.  
Table ES-1. Results of the economic analyses for the Proposed Amendments over 
the regulatory horizon of 2023  through 2043 (billions 2019$). 
Total 
costs  Health benefits
 Cost-savings 
(benefit)  Tax & fee revenue
 Total benefit
 Net benefit
 Benefit -
cost ratio  
$14.41  $8.82  $10.33  -$0.47  $18.68  $4.27  1.30 
F. Technological Feasibility 
ZEE are primarily electric, either battery- powered or corded. ZEE are available for 
most  small off -road equipment categories , including lawn and garden equipment and 
utility equipment , for both residential and professional use. The level of performance, 
number of brands, and number of equipment options have increased greatly and continue to do so today.  Today, there are at least 35 brands of zero -emission lawn 
mowers available (CARB, 2021d and 2021 e), with several brands directed at 
professional users.  Battery and electric motor technology has advanced rapidly in 
recent years, while costs have declined. It is projected that from 2010 to 2030, the price of a battery holding a kilowatt- hour of energy will decrease by over 90 percent 
(Martin, 2019). N ew technologies, such as brushless electric motors , have led to a 
significant increase in the efficiency of equipment.  
ZEE available today have  many of the same characteristics as their SORE equipment  
counterparts . Self-propelled l awn mowers with the same cutting width and adjustable 
deck heights as many SORE  lawn mowers  are available as  ZEE. Riding mowers with the 
same cutting width and speed range as many SORE  riding mowers  are also available 
as ZEE. The  wide avail ability of ZEE equivalents for SORE equipment suggest s that 
replacing  SORE equipment with ZEE is feasible. 
Approximately 52 percent of small off -road equipment in use in California are currently 
ZEE. However, among the current population of small off -road equipment, the fraction 
that is  ZEE varies substantially by equipment type . Approximately 99 percent of 
pumps are ZEE, and 5 percent of riding mowers  are ZEE . The fraction of small off -road 
equipment that is Z EE also var ies by user type, from 55 percent for resident ial users  to 
6 percent for professional  landscape rs (N orth American Industry Code System 541320 
and 561730)  (CSUF SSRC, 2019) .  
While adoption rates for ZEE among professional landscapers are low er than for 
residential users, there is substantial evidence that all new small off -road equipment 
can be zero -emission. Using ZEE is technologically feasible and can offer significant 
cost-savings to professional users. There are at least 12 brands of zero -emission lawn 
and garden equipment designed for  professional users available for sale.  
The Proposed Amendments would  allow more time  for generators  to meet emission 
standards  of zero. While zero- emission generators are available to meet users’  
ES-8 demand, t here is still a need to allow manufacturers adequate time to continue to 
innovat e and grow to meet the  future demands of the z ero-emission generator  
market. As a result, the Proposed Amendments include exhaust and evaporative 
emission standards for generators for MYs 2024 through 2027 that are more stringent 
and comprehensive than the current  emission standards , but are not zero.  These 
proposed emission standards  would  enable emission reductions to be achieved while 
allowing more time for manufacturers to develop  additional options  for zero- emission 
generators . The proposed MY 2024 -2027 emission standards are  approximately 40 to 
90 percent lower than current emission standards  for generators . Engines currently 
certified for sale  or lease for use or operatio n in California exhibit emissions below  the 
proposed MY 2024- 2027 emission standards . These engines  demonstrate the 
feasib ility of the proposed emission standards. 
The occurrence  of public safety power shut offs in recent years ha s increased the 
dependence on generators for power backup. It is important to note that the SORE 
regulations do not apply to stationary generators, which are not moved for equipment operation or storage. These stationary generators are frequently powered by natural gas or propane and usually installed on a concrete pad. To the extent that Californians 
rely on generators subject to CARB’s SORE regulations, the time between the Board 
adoption of the Proposed Amendments and the effective date of the emission 
standards of zero for  generators will provide adequate time for manufacturers to 
assess power outages in California, better understand consumer needs during tho se 
outages, and develop zero- emission generators to better meet those needs by 2028.  
G. Environmental Analysis  
The Proposed A mendments are substantively similar to a regulatory concept measure 
previously included within CARB’s 2016 State SIP Strategy.  In its  approval of the 2016 
State SIP Strategy, CARB certified an environmental analysis (EA), entitled Final 
Environmental Analy sis for the Revised Proposed 2016 State Strategy for the State 
Implementation Plan  (Final EA) , that evaluated the impacts associated with the 2016 
State SIP Strategy’s  SORE  regulatory measures . CARB  identified  mitigat ion for  those 
impacts, evaluated overarching alternatives to the 2016 State SIP Strategy and 
adopted a statement of overriding circumstances for impacts deemed significant and 
unavoidable.  While the Proposed Amendments fill in more detail with respect to 
specifying the more stringent emission standards and eventual emission standards of 
zero, the additional detail does not change the potential compliance responses 
identified in the Final EA  and associated impacts and mitigation measures from 
potential compliance -response development projects. Ra ther, the only change 
triggered by the Proposed Amendments that warrants an addendum to the Final EA is the need to add the Proposed Amendments’ detail to the project description of the 
2016 State  SIP Strategy’s SORE measures. Therefore, since the Final EA  adequately 
evaluated impacts, mitigation and alternatives associated with the 2016 State SIP 
Strategy SORE measures and the Proposed Amendments are substantively similar to 
the 2016 State  SIP Strategy  SORE measures, the Proposed Amendments do not 
trigger the need to prepare a subsequent environmental analysis.  
ES-9 H. Environmental Justice 
The Proposed Amendments would reduce statewide emissions of NO x and ROG  from 
SORE by about half in 2031, compared to the Baseline Scenario . Reducing  NO x and 
ROG  emissions is an integral part of California reaching its goal of attaining and 
maintaining national  and California ambient air quality standards  for ozone , which are 
protective of  the health and welfare of all California resident s. Consequently, all 
communities, including disadvantaged low -income  communities and communities of 
color, would benefit f rom the P roposed  Amendments.  Enhanced emission benefits in 
underserved communities are not expected . However, the Proposed Amendm ents 
would help improve the overall health of these communities through fewer instances 
of premature mortality, fewer hospital and ER  visits, and fewer lost days of work . 
These health benefits would result  from reduced tropospheric ozone and PM 
production as NO x and ROG  emissions decrease. 
Users of SORE equipment are exposed to CO, PM 2.5, and toxic air contaminants 
(TACs)  when operating equipment. R eplacing these equipment with  ZEE would result 
in decreased exposure  to these air contaminants  for equipment us ers. The Proposed 
Amendments are consistent with CARB’s environmental justice policy of  reducing 
exposure to air pollutants and reducing adverse health impacts from TACs  in all 
California communities.  
Sole-proprietorships and other small business landscap ers may be significantly 
affected  by the direct economic impacts of the Proposed Amendments. Small business 
landscapers make up more than  99 percent of landscaping businesses in California. 
The higher upfront costs of ZEE and the batteries needed to power ZEE for a full work 
day may be a significant expense for many landscaping  businesses. Purchasing all new 
ZEE in addition to the batteries may be burdensome. However, landscapers using ZEE  
may realize  net cost -savings within the first few years of purchase due to decreased 
fuel and maintenance costs , despite larger upfront costs . Furthermore , over time, 
additional savings are expected from decreased maintenance and repair costs because the businesses would  no longer have the costs of routine engine maintena nce 
and repairs. Staff expect s that a landscaping business would not  need to purchase a 
full suite of ZEE at once, thereby avoiding a significant one- time cost to transition to 
ZEE. Rather, landscaping businesses would gradually purchas e ZEE to replace SOR E 
equipment as it breaks or for other business reasons, such as upgrading equipment . 
I. Regulatory Alternatives Evaluated  
In addition to the Proposed Amendments, which is the preferred alternative, CARB staff evaluated several regulatory alternatives. First, staff evaluated an alternative that would set emission standards for all SORE to zero for MY 2024. This alternative would 
have  a $2.49 billion direct cost and a marginal increase in emission reductions for NO
x 
and ROG  compared to the Proposed Amendments. Staff rejected this alternative on 
technological feasibility grounds due to the market for zero -emission generators not 
being ready to fully meet potential demand.   
ES-10 Second, staff evaluated an alternative that would set more stringent emission 
standards for a ll SORE for MYs 2024 through 2025 and would set emission standards 
to zero for MY 2026 and subsequent model years. This alternative would cost $1.81  
billion more than the Proposed Amendments and have marginally lower emission reductions than the Proposed Amendments. Staff rejected this alternative due to its higher costs and failure to maximize the use of ZEE that is technologically feasible 
starting in MY 2024.  
Finally, staff evaluated a Small Business Alternative. This alternative would delay 
implementati on of any new emission standards until MY 2028. This alternative would 
cost $ 419 million more and would have 28 percent lower emission reductions than the 
Proposed Amendments. Staff rejected this alternative due to its failure to meet the expected emissions reductions for SORE in the 2016 State SIP Strategy. 
J. Regulatory Development Process and Outreach Efforts  
Staff held public workshops and had other meetings with interested persons during 
the development of the Proposed Amendments. Stakeholders’ comments during and after these informal pre- rulemaking discussions and in response to a separate  
solicitation of alternatives,  provided staff with useful information that staff  considered 
during development of the Proposed Amendments, and in selecting alternatives for 
consideration . 
A survey to determine the small off -road equipment  population in California  was 
conducted by California State University Fullerton Social Science Research Center  
beginning in 20 17. Throughout development of the survey, meetings of the SORE 
Working Group were held to get feedback on the survey questions. The SORE Working Group consists of interested stakeholders, including manufacturers, trade associations, government agencies, individuals,  and environmental organizations . At 
each stage of the survey, all parties were invited to give feedback on the questions 
asked , and the survey questionnaires were improved as a result.  
Staff held three pre-rulemaking public workshops to discuss the development  of the 
Proposed Amendments, in September 20 19, June 2020, and March 2021. Staff 
presented regulatory concepts , and discussed potential amendments at these 
workshops . The workshop s were attended by industry representatives , environmental 
organizations , and interested citizens. In addition to the se public  workshops, staff held 
numerous meetings with equipment and engine manufacturers , industry trade 
associations, environmental organizations , and interested residents.  
Staff also conducted outreach to inform stakeholders about the potential regulations. 
CARB staff has attended four  conventions held for landscapers in California . These 
conventions have provided opportunities for staff to inform professional landscapers 
about potential  regulat ory changes and about ZEE  capabilities and availability . CARB 
staff has presented information about zero -emission landscaping equipment and the 
potential regulatory amendments at five  meetings attended by landscapers and 
members of local governmental committees  in California .  
ES-11 Since 2018, CARB staff has  operated a dem onstration project called  the ZEE 
Roadshow, where several brands of zero -emission lawn and garden equipment 
designed for professional use are loaned to landscaping crews  throughout the state. 
This provides them with an opportunity to use ZEE without purcha sing it. The 
response has been overwhelmingly positive, with nearly all crews  finding at least one 
ZEE type that they preferred over  SORE equipment. Landscaping crews  receiving the 
ZEE Roadshow have included theme parks, colleges and universities, school d istricts, 
and municipal organizations . 
K. Justification for Regulations Different from Federal Regulations  
The differences between the proposed California requirements and existing federal 
requirements are intended to reduce NO x and ROG  emissions and replace SORE 
equipment with ZEE as soon as feasible. This would alleviate the health and 
environmental burden of SORE emissions, allow California to meet its 2016 State SIP 
Strategy commitments, and help ensure that SORE equipment sold and used in 
California compl y with the exhaust and evaporative emission standards over their 
useful life. These regulations are justified by their benefit to human health and the 
environment.  
State and federal law also authorize these differences. CARB may regulate emissions 
from of f-road engines under the authority granted to it by the California Legislature in 
the HSC, and under the provisions of the federal Clean Air Act that direct U.S. EPA to 
authorize California to adopt and enforce emission standards and other requirements 
relating to the control of emissions from off -road engines upon meeting the criteria for 
authorization established in the federal Clean Air Act.  
L. Staff Recommendation 
California Air Resources Board staff recommends that the Board adopt the Proposed Amendments to the California Code of Regulations and to the documents 
incorporate d by reference as provided in Appendices A through G. 
  
1 I. Introduction and Background  
A. Overview  
The California Air Resources Board (CARB or Board) is responsible for protecting the 
public from the harmful effects of air pollution  through the development of  programs that 
reduce the emissions of specific pollutants and their precursors. Several areas within  
California exceed natio nal ambient air quality standards  (NAAQS) set by United States 
Environmental Protection Agency (U.S. EPA)  for both fine particulate matter (PM) with 
diameter of 2.5  micrometers or smaller ( PM 2.5) and ozone. Currently, 19 areas within 
California , including the South Coast, San Francisco Bay Area, and Sacramento County  air 
basins, are nonattainment areas for NAAQS  for ozone. U.S. EPA set  a NAAQS of  70 parts 
per billion (ppb)  for ozone in 2015. Most areas of California that exceed the 70 ppb 
standard also exceed the older 75 ppb standard  set in 2008. The Revised Proposed 2016 
State Strategy for the State Implementation Plan  (2016 State SIP Strategy) sets expected 
emission reduction for attainment of  the 75 ppb standard by 2031 for all air basins in 
Californ ia. Attainment demonstrations have not yet been submitted  for the 70 ppb 
standard in the South Coast Air Basin  or other extreme and severe nonattainment areas, 
but the deadlines  are expected to be no later than 2037. 
Oxides of nitrogen (NO  and NO 2, collectively denoted as NO x) also contribute to the 
formation of PM 2.5. PM 2.5 has direct negative health impacts . There are four areas in 
California in nonattainment of the annual average NAAQS for PM 2.5, including the South 
Coast Air Basin and the San Joaquin Va lley Air Basin , according to the 2016 State SIP 
Strategy.  Those areas exceed an annual average of 12.0 micrograms per cubic meter 
(μg/m3), averaged over three years. San Joaquin Valley  and South Coast  Air Basin 
nonattainment areas  have attainment date s of 2025 to meet the annual average NAAQS. 
New attainment dates are expected soon for the other regions.  
The South Coast Air Quality Management  District (SCAQMD  and the San Joaquin Valley 
Air Pollution Control District (SJVAPCD)  are also required  to meet the  24-hour 35 μg/m3 
NAAQS  for PM 2.5 in 2024. S CAQMD  has released a draft plan showing that the South 
Coast Air Basin attained the 24- hour standard in 2020 and will maintain this standard  
going forward.   
Meeting these public health goals requires phasing out  the use of  internal combustion 
engines in both on- road and off -road applications and adopting zero-emission technology.  
CARB’s  2020 Mobile Source Strategy (MSS)  state s that “ As research continues to show 
harmful effects from air pollution at increasingly lower levels, achieving the State’s complementary goals, targets and standards will provide much -needed public health 
protection for the millions of Californians that still breathe unhealthy air and will reduce 
exposure in the State’s most highly -impacte d and disadvantaged communities. ” (CARB, 
2021a2). An important strategy to reduce harmful effects from air pollution emissi ons is 
electrification , i.e., converting all fossil fuel –burning equipment to electric power ed 
equipment . Furthermore, the  2016 State SIP Strategy identifies the need for  substantial  
2 emission reductions from small off -road engines ( SORE ) and other mobile sources and 
increased penetration of zero -emission technology . These emission reductions are needed 
to attain ambient air quality standards and  protect the health and welfare of all California 
resident s. In addition, California Health and Safety Code (HSC) §  43018  requires CARB to 
“endeavor to achieve the maximum degree of emission reduction possible from vehicular 
and ot her mobile sources in order to accomplish the attainment of the state standards at 
the earliest practicable date .” Finally, Governor Newsom’s  Executive Order ( EO) N-79-20, 
issued September 23, 2020, (EO N-79-20) orders CARB to develop and propose , 
“Strateg ies, in coordination with other  State agencies, the U.S. EPA, and local air districts , 
to achieve 100 percent zero -emission from off -road vehicles and equipment operation in 
the State by 2035.” (California Executive Order No. N -79-20, 2020).  This Staff Rep ort: 
Initial Statement of Reasons (Staff Report)  provides the basis for CARB staff’s proposal to 
amend regulations for SORE (collectively, Proposed Amendments) to reduce SORE 
emissions and accelerate the adoption of  zero-emission equipment  (ZEE) . 
SORE are spark -ignition engines rated at or below 19 kilowatts  (25.5  horsepower) , that are 
not used to propel a licensed on- road motor vehicle, an off -road motorcycle, an all -terrain 
vehicle, a marine vessel, a snowmobile, a model airplane, a model car, or  a model boat . 
SORE are predominantly used in lawn and garden equipment such as lawn mowers, string 
trimmers, and leaf blowers, as well as in other small off -road equipment such as portable 
generators , pressure  washers,  and air compressors . The vast majori ty of SORE are  fueled 
by gasoline, but some are  powered by compressed natural gas (CNG), propane, liquefied 
petroleum gas  (LPG), or liquefied natural gas (LNG) . Small off -road equipment that are 
powered by SORE are known as SORE equipment.  The use and stor age of SORE  
equipment leads to significant emissions of air pollutants, including reactive organic gases 
(ROG) and NO x. These air pollutants contribute to particulate matter ( PM) and ground -
level ozone formation  (elements of smog)  in California.  
Existing CARB and U.S. EPA emission standards for SORE have led to substantial emission 
reductions. Since 2000, emissions of pollutants that contribute to ozone and PM 2.5 
formation  from SORE have decreased by 50 percent. Even so, in California, SORE emit 
more NO x and ROG  than light -duty passenger cars , both in summer and annually . Without  
additional regulation, SORE will emit 1.8 times the amount of summertime NO x and ROG  
that California light- duty passenger vehicle s emit in 2031 (CARB, 202 0 and 2021b ). 
Operating a typical  professional lawn mower for one hour emits as much ozone- forming 
pollution as driving a new light- duty passenger car about 300 miles –approximately the 
distance from Los Angeles to Las Vegas, more than 4 hours of drive time. Operating a typical professional backpack leaf blower for one hour emits ozone- forming pollution 
comparable to driving the same light- duty passenger car about 1,100 miles – 
approximately the distance from Los Angeles to Denver, more than 15 hours of drive time. 
These comparisons are based on the lawn mower, the leaf blower, and the light -duty 
passenger car having emissions equal to their respective emission standards.   
3 It is necessary to update the SORE regulations t o meet the expected  emission reduction s 
put forth in the 2016 State SIP Strategy and the goals in  EO N-79-20, one of which is to 
”transition to  100 percent zero -emission off-road vehicles and equipment  by 2035 where 
feasible. ” (California Executive Order No. N -79-20, 2020) . A transition to ZEE  is not  
expected to occur without  the Proposed Amendments. Without further regulation,  the 
SORE equipment population is projected to be higher in 2043 than it is  in 2021 (CARB, 
2020) . 
ZEE produce  no direct exhaust nor evaporative emissions of any criteria pollutant or 
precursor pollutant and help protect public health,  attain NAAQS , reduce petroleum use, 
and meet sustainability  objectives.  ZEE include manual equipment,  corded electric small 
off-road equipment (i.e., equipment that is powered through an electrical cord and is 
plugged into an electrical outlet), and battery -powered electric small off -road equipment.  
Manual equipment, such as reel mowers, brooms, rakes and scythes have been available 
since before SORE equipment  was first produced . Electric small off -road equipment ha ve 
been available for decades. Technological improvements have resulted in the performance of currently available ZEE being comparable to the performance of  SORE equipment.  This 
Staff Report focuses on small off -road equipment other than manual equipment when 
discussing ZEE.  
The Proposed Amendments would accelerate the t ransition to  ZEE by setting  evaporative 
and exhaust emission standards to zero for new SORE  (engines  or equipment  produced 
for sale  or lease for use or operation in Califor nia), except engines used exclusively in 
generators,  for model year (MY)  2024  and subsequent model years . Implementing 
emission standards of zero [0.00 g rams of  hydrocarbons ( HC) + NO
x per kilowatt -hour, or 
g·kWh-1, for exhaust emissions and 0.00 g rams  per test for evaporative emissions ] does not 
necessarily mean  that all new sales of small off -road equipment would be  ZEE. Banked 
emission reduction credits could be used to offset emissions from SORE for up to five 
model years after the credits were generated.  Also, e ngines or equipment emitting below 
0.005 g·kWh-1 or g·test-1 could be certified to meet emission standards of zero . However, 
staff believes that  it is unlikely that engines or equipment meeting emission standards  of 
zero will be manufactured.  It is more likely that manufacturers will use emission reduction 
credits in the near -term to offset emissions from SORE while the credits are available.  
Currently, most  ZEE is either battery- powered or corded  electric equipment, but fuel cells 
could also be used in place of engines subject to the SORE r egulations.  Under the 
Proposed Amendments, new generators  would be subject to  more stringent  emission 
standards for MYs 2024  through 2027 , and a  zero- emission standard for MY 2028 and 
subsequent model years. Any remaining emission reduction  credits may be used to allow 
for continued  produc tion of SORE for sale or lease for use or operation  in California. The 
Proposed Amendments would also amend existing credit programs and make other  
changes to the SORE regu lation s to improve consistency and increase compliance 
flexibility for  manufacturers , while reaching lower emission levels and maintaining 
enforceability.   
4 The remainder of th is chapter describes CARB’s legal authority to regulate SORE 
emissions, provides an overview of the SORE r egulations and their history, summarizes the  
Proposed Amendments, and provides background information about  the expected  
emission reductions from the 2016 State SIP Strategy and the MSS that necessitate  
replacement of all SORE equipment  by ZEE  (CARB , 2017b and 2021 a2). This chapter also 
provides a synopsis of the current ZEE market and potential challenges for ZEE 
deployment.  The remainder of  this Staff R eport provides the rationale for the P roposed 
Amendments, summarizes the regulatory development process, and describes the 
potential environmental and econom ic benefits and impacts of the P roposed  Amendments 
and alternatives  that staff considered . 
B. Legal Authority  and Responsibilities  
1. State Law  
Under California HSC sections 39500 and 39602, CARB is the air pollution control agency 
responsible for controlling emissions from motor vehicles “for all purposes set forth in 
federal law.”  Under HSC section 39602.5,  CARB is required to “adopt rules and 
regulations pursuant to Section 43013 that  … will achieve ambient air quality standards 
required by the federal Clean Air Act  … in all areas of the state by the applicable 
attainment date, and to maintain these standards thereafter.” Specifically named among 
CARB’s general duties and po wers (HSC §§ 39600- 39619.8) are the responsibilities to 
prepare California’s State Implementation Plan ( SIP) and to coordinate all local air quality 
management district activities necessary to comply with the f ederal Clean Air Act . 
Furthermore, HSC section  43013 requires CARB to  “adopt and implement motor vehicle 
emission standards, in- use performance standards, and motor vehicle fuel specifications 
for the control of air contaminants and sources of air pollution which the state board has found to be necessary, cost effective, and technologically feasible, to carry out the 
purposes” of its enabling statutory authority. Adoption and implementation of emission 
standards carries out many purposes provided in CARB’s enabling statutory authority, 
including the fo llowing purpose : “The control and elimination of  … air pollutants [are]  of 
prime importance for the protection and preservation of the public health and well -being, 
and for the prevention of irritation to the senses, interference with visibility , and damag e 
to vegetation and property.” (HSC section 43000, subd. (b).) HSC section  43018 requires 
that CARB endeavor to achieve the maximum degree of technologically  feasible, cost 
effective reductions of emissions from all mobile source categories under i ts juris diction , 
including off -road mobile sources such as SORE,  to accomplish the attainment of ambient 
air quality  standards at the earliest practicable date . Under its statutory authority, CARB 
may adopt test and certification procedures to ensure compliance with CARB’s emission standards (HSC sections 43101, 43102 , and 43104) . 
To comply with HSC provisions noted above, the Board adopted , and has since amended,  
the exhaust and evaporative regulations for SORE found in California Code of Regulations  
(CCR) , Title 13 , sections  2400 through 2409 and  2750 through 2774, and  test and 
certification procedures  incorporated by reference  therein . The regulations contain the  
performance standards and specifications—including SORE exhaust and evaporative  
5 emission standards—that must be met by equipment manufacturers to obtain CARB 
certification in the form of a n Executive O rder of Certification . The test procedures verify 
comp liance with performance standards and specifications, and the certification 
procedure s detail requirements for evaporative emission control system certification . 
These regulations and certification and test procedures help CARB verify that engines sold 
in California are certified and labeled to meet all applicable requirements. 
The federal Clean Air Act , section 209(e)(1)  preempts certain SORE  from CARB  regulation 
of emission standards, which are  new engines used in construction  equipment or vehicles 
or used in farm equipment or vehicles and which are smaller than  175 hor sepower . 
Approximately 11 percent of small off -road equipment in California are  construction 
equipment or vehicles or farm equipment or vehicles which use engines smaller than 175 
horsepo wer. 
2. Federal Law  
Section 209( e) of the f ederal Clean Air Act  uniquely grants  the State of California the 
authority to adopt and enforce rules to control emissions from nonroad engine or 
vehicular  sources  within the state, including SORE  (with  the exception of new engines 
which are used in construction equipment or vehicles or used in farm equipment or vehicles and which are smaller than 175 horsepower, as discussed in section I.A.1. of this 
Staff Report) . California is allowed an exemption from fe deral Clean Air Act provisions that 
otherwise prevent states from setting their own emission standards for mobile source 
emissions. The exemption recognizes California’s long standing air pollution challenges 
and pioneering efforts to reduce mobile source emissions.  
C. Regulatory History 
Emissions from SORE occur both when the engine is running (exhaust  and evaporative  
emissions) and when it is not running  (evaporative emissions) . Exhaust emissions contain 
both  NO
x and ROG , while evaporative emissions contain  ROG.  CARB adopted the first 
SORE regulations in 1990 when setting the first exhaust emission standard s. The exhaust 
emission regulations include emission standards for HCa, NO x, carbon monoxide (CO), and 
PM. The exhaust emission standards were impl emented in two tiers between MY s 1995 
and 2002.  Further exhaust emission standards and the first CARB evaporative emission 
standards for SORE were adopted in 2003.  Evaporative  emissions occur both  when the 
engine is operati ng and when it is not. The most recent SORE exhaust emission standards 
were implemented between MY s 2000 and 2008 . The evaporative emission standards 
were implemented between MY s 2006 and  2013. 
                                            
a Hydrocarbons are chemical compounds consisting of carbon and hydrogen only; many hydrocarbons are 
ROG . Emissions of all organic compounds are measured to verify compliance with the emission standards for 
hydrocarbons for gasoline -fueled engines.   
6 The most recent a mendments to the evaporative emission regulations were adopted in 
2016, following validation stud ies that found  low rates of compliance with existing 
emission standards. A major purpose of these amendments was to  increase compliance 
rates and  facilitate compliance testing and enforcement actions.  The amendments 
included th e following: the requirement for one engine instead of five to be tested for an 
initial compliance  determination ; the option for the Executive Officer to purchase 
equipment for compliance testing ; and the requirement for bonds to be posted by 
manufacturers  without sufficient U.S. assets to cover potential enforcement penalties.  The 
2016 amendments did not change the emission standards except to include fuel line 
permeation emission standards for engines with displacementb less than or equal to 
80 cubic centimeters  (cc). These fuel line permeation emission standards were similar to 
those included in U.S. EPA regulations and implemented between MY s 2012 and 2016.  
Tables  I-1, I-2 , and I -3 provide the current SORE exhaust and evaporative emission 
standards, respectively.  CARB staff continues  to perform compliance testing to hold 
manufacturers accountable for achieving the certified emission levels and ensure 
Californians realize the air qua lity benefits o f the current regulations.  
Both exhaust and evaporative emission regulations include  emission reduction credit 
programs, which allow manufacturers to produce engines that emit  at levels higher than 
the emission standards if they offset those with engines that emi t at levels lower than the 
emission standards. The exhaust emission reduction credit  program allows for credit 
generation for ZEE.  The credit programs are reviewed in more detail in Chapter  II. 
Table I -1. Current SORE exhaust emission standards. 
Displacement  category HC + NO x  
(g·kWh-1)c CO  
(g·kWh-1) Particulate matter  
(g·kWh
-1) 
< 50 cc  50 536 2.0 
50-80 cc, inclusive  72 536 2.0 
> 80 cc - < 225 cc  10.0 549 NA 
225-825 cc, inclusive  8.0 549 NA 
> 825 cc  8.0 549 NA 
                                            
b Displace ment is the total swept volume of all the cylinders in an engine, usually expressed in cubic 
centimeters or liters, and is an expression of an engine’s size.  
c g·kWh-1: grams (g) of emissions per kilowatt -hour (kWh). A kilowatt -hour is a unit of energy equal to one 
kilowatt of power sustained for one hour.   
7 Table I -2. Current SORE diurnal  emission standards. 
Displacement  category Current d iurnal emission standard  
(g organic material hydrocarbon equivalent·day-1) 
≤ 80 cc  N/A 
> 80 cc - < 225 cc  
except walk-behind mowers 0.95 + 0.056 × nominal capacity (liters)  
> 80 cc - < 225 cc  
walk-behind mowers  1.0 
≥ 225 cc  1.20 + 0.056 × nominal capacity (liters)  
Table I -3. Current permeation emission standards for SORE with displacement 
less than or equal to 80 cc . 
Displacement 
category Fuel line permeation emissionsd 
(g ROG ·m-2·day-1) Fuel tank permeation emissions 
(g ROG ·m-2·day-1) 
≤ 80 cc  15 or 225  2.0 
All SORE with displacement greater than 80 cc must meet the evaporative  emission 
standards noted in T able I -2 in compliance testing, but manufacturers may use  evaporative 
emission control system components that meet  design standards for certification.  The 
design standards includ e fuel tank and fuel lines permeation emission standards . These 
permeation emission standards set a maximum amount of ROG  that can pene trate  
through the wall s of fuel lines or fuel tanks and evaporate on outside surfaces. The design 
standard for carbon canisters sets a  minimum working capacity that is proportional to the 
nominal capacity of an engine’s fuel tank.  Carbon canisters  control  fuel tank venting 
emissions  to reduce their release  to the atmosphere. SORE with displacement less than or 
equal to 80 cc must meet permeation emission standard s for fuel tanks  and fuel lines . 
D. Criteria Air Pollutants and Air Quality Commitments 
The f ederal Clean Air Act requires the U.S.  EPA to set NAAQS for six of the most common 
air pollutants, which  are collectively known as “criteria air pollutants” or simply “criteria 
pollutants .” Criteria pollutants include ground -level ozone, PM , CO, lead, sulfur dioxide, 
and nitrogen dioxide  (NO 2). Emissions of NO x and ROG  from SORE contribute to three of 
these—ozone, PM, and NO 2—either directly (NO 2 and PM) or indirectly ( NO 2, ozone and 
PM) and all have negative health effects.  The next subsections of this chapter cover the 
following topics : Subsection I. D.1 provide s a brief review of the negative health effects 
associated with criteria air pollutants;  subsection I. D.2 gives an overview of  expected  
                                            
d The fuel line permeation emission standard of 225 g ROG ·m-2·day-1 applies to fuel lines used in chainsaws; 
fuel lines in other equipment must meet a 15 g ROG ·m-2·day-1 fuel line permeation emission standard.   
8 emission reductions in the 2016 State SIP Strategy  and the MSS ; and  subsection I.D .3 
discusses EO  N-79-20 and how the Proposed Amendments will help reach the goals 
stated therein. These goals and commitments prompted and guided the development of 
the Proposed Amendments to the SORE r egulations. Section D of Chapter IV provides a  
more in -depth review of the negative health effects associated with the pollutants.  
1. Negative Health Effects  
NO x is a set of highly reactive gases, NO 2 and NO, which are emitted from internal 
combustion engines.  The majority of NO x emissions from internal combustion engines are 
NO, but NO 2 is rapidly formed in the presence of ozone.  Breathing air with a high 
concentration of NO 2 can irritate airways in the human respiratory system.  Such exposures 
over short periods can aggravate respiratory diseases, particularly asthma, leading to 
respiratory symptoms (such as coughing, wheezing or difficulty breathing), hospital admissions and emergency room  (ER) visits . Longer exposures to elevated concentrations 
of NO
x may contribu te to the development of asthma and potentially increase 
susceptibility to respiratory infections. People with asthma, as well as children and the elderly, are generally at greater risk.  NO
x reacts with other chemicals in the air to form 
both ozone and PM 2.5 (World Health Organization, Europe , 200 6).  
Both ozone and PM , especially  PM 2.5, are harmful when inhaled  (Xing et al. , 2016).  Ozone 
can trigger a variety of health problems including chest pain, coughing, throat irritation, and airway inflammation. It can also reduce lung function and harm lung tissue.  Ozone can 
worsen bronchitis, emphysema, and asthma, leading to increased medical complications  
(The Royal Society, 2008) . Similarly, studies have linked daily exposure to PM
2.5 with 
hospitalization for h eart- and lung -related causes. Exposure to PM 2.5 also increase s the 
number of ER  visits and exacerbates asthma and other respiratory diseases, such as 
chronic obstructive pulmonary disease . It can also  increase the severity of respiratory 
symptoms and the frequency of asthma medication use. Exposure to ozone and PM 2.5 was 
estimated to contribute to between 16,000 and 40,400 premature deaths in California in 
2012 (Wang  et al., 2019) .  
ROG include all organic gas compounds emitted to the atmosphere except  certain less 
reactive compounds, such as methane and ethane. ROG contributes to the formation of 
tropospheric ozone through reaction with NO x in the presence of sunlight (The Royal 
Society, 2008). Additionally, some components of ROG can have direct healt h effects, in 
particular, those that are toxic air contaminants (TAC). According to HSC section  39655 , 
TACs are “air pollutants which may cause or contribute to an increase in mortality or an 
increase in serious illness, or which may pose a present or potential hazard to human 
health.”  
2. State Implementation Plan  
All geographic areas in California that are designated nonattainment areas for one or 
more  NAAQS are required by the federal Clean Air Act  to submit a SIP. Under federal 
Clean Air Act section  110, SIPs provide for the “implementation, maintenance, and  
9 enforcement” of NAAQS. Areas with more significant air quality challenges are required to 
include strategies to attain the relevant NAAQS.  Substantial progress has been achieved 
in reducing NO x and ROG  emissions  in California  through implementation of CARB’s 
existing mobile source programs, and it is expected that these programs will continue to provide further reductions through 2031, contributing significantly to meeting ambient  air 
quality standards. As a result of SORE regulations and  increasing adoption of ZEE by 
users, emissions of NO
x and ROG  from SORE have decreased by 50 percent since 2000.  
However, the most recent ozone NAAQS are more stringent than the previous ozone 
NAAQS  and warrant more extensive emissions control strategies.  Although California has 
significantly reduced ambient ozone concentrations, the challenges posed by the more 
stringent NAAQS  prompted the reclassification of the San Joaquin Valley and South Coa st 
nonattainment desig nations. Both regions are now classified as “extreme nonattainment” 
with regard to the 8 -hour ozone standard.  For example, to meet the 75 ppb NAAQS for 
ozone by 2031, the South Coast Air Basin will require an approximate 80 percent reduction in ambient NO
x from current levels.  Statewide, about 12 million Californians live 
in communities that still exceed the federal ozone and PM 2.5 standards.  Federal Clean Air 
Act §  182(e)(5)  provides that extreme nonattainment areas  may rely on the development 
of new technologies or improvement of existing technologies, in addition to other enforceable commitments . The 2016 State SIP Strategy states that achieving this reduction 
will require comprehensive efforts to address emissions from both stationary and mobile 
sources including SORE  through ongoing implementation of already adopted measures, as 
well as new actions.  
In 2007, CARB adopted SIPs for the federal 1997 80 parts per billion (ppb) 8- hour ozone 
NAAQS (CARB, 2007b) . The 2007 SIPs included a comprehensive State Strategy (2007 
State SIP Strategy) and local attainment plans . These plans were designed to attain the 
1997 80 ppb 8 -hour ozone NAAQS, as well as the 1997 65 micrograms per cubic meter 
(µg/m
3) 24-hour and 15 µg/m3 annual PM 2.5 NAAQS . The 2007 State SIP Strat egy called for 
a combination of technically feasible and cost -effective control strategies. In 2009 and 
2011, CARB adopted revisions to the 2007 State SIP Strategy , updating the assumptions 
and control stra tegy to demonstrate attainment (CARB, 2009 and 201 1a). 
The 2007 State SIP Strategy includes the following measure for reduction of emissions 
from SORE : Reduce exhaust emission from SORE by tightening emission limits as a long -
term concept (CARB, 2007 a). 
In 2017, CARB adopted the 2016 State SIP Strategy ( CARB, 2017b) . The 2016 State SIP 
Strategy included control measures to achieve the reductions necessary from mobile 
sources, fuels, and consumer products to meet the 1997 80 ppb 8- hour ozone, 2008 75 
ppb 8 -hour ozone, and 2012 12 µg/m3 PM 2.5 NAAQS. The 2016 State SIP Strategy 
proposed a suite of regulatory and incentive programs, which, in combination with local 
actions, were designed to achieve emission reductions to meet the NAAQS . The 2016 
State SIP Strategy includes a new measure for SORE  with the goal to reduce SORE  
10 emissions and increase the penetration of zero -emission technology.  The 2016 State SIP 
Strategy includes the following actions and expected emission reductions for SORE :  
Reduce exhaust and evaporative emissions from SORE through enhanced enforcement of 
the current emission standards, adoption of more stringent  exhaust and evaporative 
emission standards, and increased use of ZEE . 
Develop additional strategies for transitioning to zero -emission technologies, including an 
initial focus on incentives for use of ZEE . 
Propose regulations to r educ e SORE emissions by 2031 by the following amounts:  
• Statewide:  Reduce NO x emissions by 4 tons per day ( tpd), ROG  emissions by 
36 tpd, and PM 2.5 by < 0.1 tpd. 
• South Coast Air Basin:  Reduce NO x emissions by 2 tpd and ROG  emissions by 16 
tpd.  
• San Joaquin Valley Air Basin:  Reduce NO x emissions by 0.3 tpd. 
In November 2016, C ARB staff pr oposed  to the Board and the Board approved for 
adoption amendments to the evaporative emission requirements for SORE with provisions 
for enhanced enforcement of the evaporative emission standards. Staff also began 
conducting more frequent compliance testing in Fall 2016.  CARB staff has  pursued several 
strategies to encourage the adoption of  zero-emission technologies as detailed in 
subsection E of this chapter . The Proposed Amendments described in Chapter s II and XI 
are designed to achieve the expected emission reductions for SORE.  
The 2016 State SIP Strategy also includes a measure for “Further Deployment of Cleaner 
Technologies: O ff-Road Equipment” specific to the South Coast Air Basin. This measure 
would achieve an estimated  18 tpd of NO x emission reductions and 20 tpd of ROG 
emission reductions by 2031 but does not specify the source of the reductions . The 
measure calls on CARB and the local air district to i dentify and develop mechanisms to 
incentivize deployment of near -zero and zero -emission technologies, and to expand and 
enhance existing incentive and other innovative funding program s for off -road equipment 
to increase the emphasis on and support for ZEE  and provide near -source risk reduction 
for operators of the equipment.  The Proposed Amendments described in Chapter s II and 
XI include changes to expand existing emission reduction credit programs to further 
incentivize and accelerate the production  of ZEE. 
Amendments to regulations for SORE are necessary.  In the absence of tighter emission 
standards for SORE, emissions of the ozone precursors NO x and ROG  are expected to 
increas e as Ca lifornia’s population continues to grow . Maximum emissions reductions must 
be achieved from SORE in order to avoid this increase  in emissions and instead  reduce 
SORE emissions to achieve 2016 State SIP Strategy commitments necessary to attain the 
ozone NAAQS and protect public health and welfare.   
11 3. Executive Order N -79-20 
In September  2020, Governor Gavin Newsom  issued Executive Order N -79-20, which  sets 
a goal to  “transition to  100 percent zero -emission off-road vehicles and equipment by 
2035 where feasible.”  EO N-79-20 specifically directs CARB, to the ex tent consistent with 
State and f ederal law, to develop and propose strategies, in coordination with other state 
agencies, U.S. EPA and local air districts,  to achieve 100 percent zero -emission from off -
road vehicles and equipment operations in the State by 2035.  The EO further states that in 
implementing the strategies, CARB  “shall act  consistently with technological feasibility and 
cost-effectiveness .” (Califo rnia Executive Order No. N -79-20, 2020).   
The Proposed Amendments are a n important part of meeting the 2035 zero- emission goal 
for off -road vehicles and equipment  operations . Setting SORE exhaust and evaporative 
emission standards to zero for new engines  (engines produced for sale or lease for use or 
operation  in California) for MY 2024 and subsequent model years for all equipment  except 
generators, and for MY  2028 and subsequent model years for generators , will result in a 
significant change in the in- use fleet of  SORE  equipment  to ZEE  by 2035. As described in 
the next section and following chapters, development of the Proposed Amendments took 
into account the typical useful lifetime  of current SORE equipment and technological 
feasibility and cost -effective ness of current and anticipated zero -emission options.  
E. Technological Feasibility  
1. Current ZEE A vailability and Usage Rates 
ZEE have been available for many equipment types for decades . The level of performance, 
number of brands, and number of equipment options have increased greatly and continue 
to do so today.  Battery and electric motor technology has advanced rapidly in recent 
years, while costs have declined. Advances in battery technology have allowed for  the 
price of batteries to fall  precipitously . It is projected  that from 2010 to 2030, the price of a 
battery holding a kilowatt- hour of energy  will decrease  by over 90 percent  (Martin,  2019). 
The increase in use of brushless electric motors has led to a significant increase in the 
efficienc y of equipment using that technology. These developments have led to a 
significant increase in ZEE product development over the last several years.  
ZEE on the market today ha ve a broad range of  both capability and price.  For residential -
grade equipment, th ere are currently at least 35 different manufacturers of ZE E 
(CARB,  2021c). For lawn  mowers, one of the most abundant  types of small off -road 
equipment , there are at least 28 brands of ZEE available, with many brands offering 
multiple models.  The number of manufacturers has risen steadily over the past 15 years , 
and is likely to continue rising as the market for ZEE matures.  Residential users can 
purchase quality ZEE at most home improvement retailers  and hardware stores .  
For professional -grad e equipment, there are at least twelve  different manufacturers of ZEE 
(CARB, 2021c) with at least nine brands of ZEE lawnmowers. Many of these manufacturers 
are those who  currently make SORE equipment  trusted by professional users.  This  
12 equipment can be purchased directly from the manufacturer or through  certified  dealers 
located around the state , similar to purchasing gasoline- powered equipment . 
Generators are another common type of small off -road equipment. Zero-e mission 
generators are available  to meet u sers’ demand, and their price depends largely on the 
cost of  energy storage. Th e expected  decrease in the cost of energy storage  will both 
decrease the average cost of a zero -emission generator and increase energy storage . 
Some small off -road equipment is specialized and used in emergency response. These 
include chainsaws, pumps, and cutoff saws. While zero -emission chainsaws, pumps, and 
cutoff saws are available , new engines used in chainsaws with displacement 45 cc and 
above, pumps with displacement 40 cc  and above, and cutoff saws are preempt under 
section 209(e)(1)  of the federal Clean Air Act , and therefore, not subject to the SORE  
regulations.  Chainsaws designed for use by firefighters typically use engines with 
displacement 45 cc or above (Stihl  USA,  2021f ), and fire pumps typically use engines with 
displacement 40 cc or above ( CET, 2021).  Section 2403(f) of the exhaust emission 
regulations provides that  “fire and police departments, and other entities that specialize in 
emergency response may purchase emergency equipment powered by a non-California 
certified engine only when such equipment with a California -certified engine is not 
available.” This provision allows  a fire or police department, or other entity that specializes 
in emergency response, to submit a request to the Executive Officer for approval to 
purchase emergency equipment powered by a non- California certified engine, if no 
equipment powered by California certified engines and consistent with the entity’s application requirements is availa ble. CARB has not received any request from a fire or 
police department, or other entity that specializes in emergency response to purchase emergency equipment powered by a non- California certified engine. The Proposed 
Amendments would not impact this existing provision.  
To better understand the small off -road equipment population in California, CARB 
contracted with the Social Science Research Center (SSRC)  at California State University, 
Fullerton (CSUF) to conduct an intensive survey between 2017 and 2019 of households, 
nonlandscaping businesses, and landscapers  on their ownership  and use of small off -road 
equipment , and other related topics (CSUF survey)  (CSUF SSRC, 2019). Staff developed 
the survey questions in close collaboration with SSRC, industry and  other interested 
stakeholders through a series of working group meetings. The main goal of the survey was to calculate a more accurate inventory of small off -road equipment in California for 
emissions modeling. The survey reached over 1,100 households, 1,300 businesses and 600 
landscaping businesses throughout the state. Topics included ownership, use rates, 
knowledge of ZEE, and maintenance practices. The final report estimates the total small 
off-road equipment population and the populations of several equipment types.  
According to the CSUF survey, almost half of households own at least one piece of lawn 
and garden equipment. Nearly 40 percent of households own another piece of small off -
road equipment such as an air compressor, generator, or pressure washer. The residential 
sector makes up the majority of the small off -road equipment population in California, with 
a total population of about 26.4  million pieces of equipment (CSUF SSRC, 2019). Of the  
13 26.4 million pieces of residential small off -road equipment in California, about 15.5 million 
are ZEE. This represents a current ZEE ownership rate of 59 percent for residential small 
off-road equipment in California. Residential users use their equipment less frequently 
than professional users, and thus replace equipment less frequently. The CSUF survey 
showed that the median age of equipment is six years for a residential lawnmower and five years for a trimmer/edger. Only 7 percent of households stated that they intended to buy 
any additional pieces of small off -road equipment or replacements for their current small 
off-road equipment in the next year.  
The professional sector makes up a relatively small portion of the SORE equipment 
population in the state. Per the CSUF survey, the total professional SORE equipment 
population is about 2.87 million, which is about 10  percent of the total population in 
California. Although professional equipment make up only a small fraction of all SORE, 
professional equipment are used far more frequently than residential equipment and produce the majority of SORE emissions in California. Of the 2.87 million pieces of 
professional small off -road equipment, only about 960,000, or 33 percent, are ZEE. Eight 
percent of small off -road equipment used by landscaping businesses are ZEE.   
2. Comparison of ZEE and SORE Equipment 
For the most common types of SORE equipment, there are ZEE equivalents available in 
the market with similar or better performance characteristics  and lifetime . For the purpose 
of comparing performance characteristics  and lifetime , staff evaluated some of the most 
popular types of small off -road equipment available  in the market for both residential and 
professional use . This comparison is not comprehensive and does not demonstrate that 
SORE equipment and ZEE have identical performance.  
For both residential and professional equipment analyses, staff evaluated SORE 
equipment and their ZEE equivalents. T he nine most common types of small off -road 
equipment  were evaluated. For residential equipment, these make up 98 percent  of in-use 
residential  SORE  equipment  that would be impacted by the Proposed Amendments  is 
considered in the analysis (CARB, 2020). For professional equipment, the nine equipment 
types evaluated by CARB make up 91 percent of  the professional SORE equipment that 
would be impacted by the Proposed Amendments is consider ed by this  analysis (CARB, 
2020).  
a. Performance Characteristics  
i. Residential Equipment  
Staff analyzed the performance of residential SORE equipment and ZEE that are similar in 
functionality, as shown in Table I -4. The analysis focused on bestselling SORE equipment 
models for each equipment type, using data from major home improvement retailers regarding median price and popularity.  The ZEE was selected for similar cha racteristics to 
the SORE equipment . Staff reviewed  characteristics of each piece of equipment to 
determine what work it could  accomplish. For instance, with the lawn mower, cutting 
width , self-propulsion, and cutting height adjustment  were considered. The SORE and  
14 zero- emission mowers both have 21- inch cutting widths , and have six cutting height 
positions . These characteristics determine how quickly a lawn mower is able to cut grass. 
The zero -emission lawn mower is self -propelled, while the SORE lawn mower is not, so the 
zero- emission lawn mower would be easier to operate for most users. With  similar 
characteristics, the lawn mowers are equally capable of cutting a lawn in similar time.  
Staff compared leaf blowers that can move similar amounts of leaves based on air flows 
stated in equipment specifications. The SORE equipment considered moves air at 453 
cubic feet per minute, while the ZEE ranges from 250 to 500 cubic feet per minute.  The 
blowing force of the SORE blower is 15.8 Newtons. The z ero-emission leaf blower has a 
blowing force of 2 1 Newtons. The chainsaws compared have the same bar length, 
allowing them to cut similar sized objects . The pressure washers both create streams with 
3,000 pounds per square inch of pressure and have interchangeable nozzles. The zero-emission pressure washer has a maximum flowrate of 1.3 gallons per minute (gpm), while the SORE pressure washer has a maximum flowrate of 2.3 gpm. The SORE  riding mower 
has a 48 inch cutting deck. While 48 inch residential -grade electric riding mowers are less 
common, both 38 inch and 54 inch versions are available. Both the SORE and electric riding mowers are mulching capable with side discharge. The SORE riding mower has a top drive speed of 5.5 miles per hour (mph), while the z ero-emission riding mower has a 
top drive speed of 7 mph.  The SORE snow blower has an 18 inch clearing swath, while the 
electric has a 20  inch clearing swath. Both have adjustable c hutes to change the direction 
of snow throw.  The SORE string trimmer has a cutting swath of 18 inches and bump feed. 
The battery- electric string trimmer has a cutting  swath range of 14 to 16 inches and also 
has bump feed. While the cutting swath of the electric string trimmer is slightly smaller than its SORE  counterpart, it allo ws for a wider range of string diameters and has an 
adjustable cutting depth. Both trimmers have attachments that can be changed for other tool capabilities.  
Generators are different from other SORE, in that their function is to generate electricity. 
Beca use of this, zero -emission generators often do not contain an electric motor.
e Instead, 
zero- emission generators often convert chemical energy to electrical energy without the 
use of an electric motor. C haracteristics  that establish functionality of a SORE  or zero-
emission generator  include the types and number of receptacles available on the 
generator  and the power rating . Most SORE and zero -emission generators are equipped 
with 120- volt power output, but both are available with 240 -volt output as well. Th e SORE 
and zero -emission generators cited in Table I -4 both have 120- volt output. The runtime of 
a zero- emission generator  that does not have solar or wind attachments  is determined by 
the energy storage  and the load  on the generator . Therefore, if a longer runtime is 
required  under the same load , a larger energy storage zero- emission generator must be 
                                            
e In this context, an electric motor is a rotating machine that transforms electrical energy into mechanical 
energy .  
15 purchased. Zero -emission generators can also be purchased with solar or wind generation 
equipment , which can add to the available power and runtime.  
The SORE equipment and ZEE evaluated may have different runtimes, but the runtime of 
the ZEE can always be extended through the use of additional batteries.  Additional 
batteries can increase the cost of the equipment to complete the job. However, if the 
equip ment is used enough to necessitate extra batteries, it is more likely that users will 
make back the additional investment through decreased maintenance and fuel costs.  
Table I -4. Residential SORE equipment and ZEE used in performance analysis. 
Type of equipment  Make and model of SORE equipment SORE equipment citation Make and model of ZEE  ZEE citation 
Chainsaw  Ryobi RY 3716   (Home Depot, 
2020l)  DEWALT DCCS670T1  (Home Depot, 2020d)  
Portable Generator  Briggs & 
Stratton #030744  (Home Depot, 2020b)  Goal Zero Yeti 
1500  (Goal Zero, 2020b ) 
Lawn Mower  Troy-Bilt TB170 
XP Space Saver  (Home Depot,  
2020c) Ego LM2102SP  (Home Depot, 2020f)  
Leaf Blower / 
Vacuum  Echo PB -2520  (Home Depot, 
2020e)  Ego LB6500  (Lowes, 2021a)  
Pressure 
Washer  Ryobi RY803001  (Home Depot, 2020m)  Sun Joe SPX4600  (Home Depot, 2020n)  
Pump <  2 hp GPT Co. XG10  (Lowes, 2021b)  RYOBI P750 -
P163  (Home Depot, 
2020k)  
Riding Mower  John Deere BG21077  (Home Depot, 2020h)  RYOBI - 
RY48140  (Home Depot, 2021a) 
Snow Blower  Briggs & 
Stratton 
#1697099  (Home Depot, 
2020a)  Greenworks 
SN200  (Home Depot, 2020g)  
Trimmer/Edger/Brush Cutter  Toro 51978  (Home Depot, 2020o)  Milwaukee 2825- 21ST  (Home Depot, 2021b) 
ii. Professional equipment  
For each professional equipment type, SORE equipment and ZEE that are similar in 
functionality were selected for performance analysis , as shown in Table I -5. Staff reviewed  
characteristics of each piece of equipment to determine what work it could  accomplish. 
For instance, with the riding mower , deck size, speed range, and discharge system were 
evaluated. Both riding mowers have a 60-inch deck size, a 10 mile -per-hour top speed,  
16 side discharge decks, and twin lever control  for steering. With these similar characteristics, 
the riding mowers are expected to be able to accomplish the same jobs.  
The SORE and zero -emission chainsaws compared in the performance analysis both have 
18-inch bar lengths. The manufacturer’s description of the zero- emission chainsaw claims it 
“Provides expected power and torque of a 50cc gas engine.” (Greenworks, 2021 b). 
Chainsaws using engines with displacement 45 cc or greater are preempt and would not 
be impacted by the Proposed Amendments.  The walk -behind lawn mowers compared are 
both self -propelled and have 21 -inch cutting decks. Both mowers are  capable of mulch ing 
or bagging the grass cuttings. The SORE lawn mower has drive speeds between 2.1 and  
4.0 mph, while the ZEE lawn mower  has drive speed between 1.1 and 3. 3 mph.  The SORE 
leaf blower has a maximum air velocity of 232 miles per hour, while the ZEE leaf blower 
has a maximum of 18 8 miles per hour.  The blowing force of the zero -emission leaf blower 
is 21 Newtons, while the blowing force of the SORE leaf blower is 30 N ewtons. The 
trimmers compared have similar cutting widths, with the SORE trimmer at 46 centimeters 
and the zero -emission trimmer at 40 cm. The SORE snow blower has a 28- inch clearing 
width and can throw the snow up to 45 feet. The zero -emission snow blower  has a 21 inch 
clearing width and can throw snow up to 40 feet.  For the pressure washers, both are cold 
water units. Both units have a maximum pressure of  4,000 psi and maximum flow rate of 
3.5 gallons per minute. Both the SORE and zero- emission pressure w ashers  can operate 
over a variety of nozzle angles.  
The SORE generator cited in Table I -5 has both 120- volt and 240 -volt output . The zero-
emission generator has 120- volt, universal serial bus (USB) A, USB -C, USB -C power 
delivery, 6 mm port, 12 -volt car por t, and a 12 -volt high power port.  The runtime of a 
zero- emission generator that does not have solar or wind attachments is determined by 
the energy storage  and the load . Therefore, if a longer runtime is required, a larger energy  
storage zero -emission generator must be purchased. Zero -emission generators can be 
purchased with solar or wind generation equipment, which can add to the available power 
and runtime. The Goal Zero 3000X is compatible with solar attachments, which can be purchased separately.  More information on zero- emission generators is in section I.E.3.b, 
below.  
Runtime  for ZEE is determined by the battery capacity and the load. For  most  professional 
equipment, including all the handheld equipment, extra batteries can be purchased at any time.  Some riding mowers, including the Gravely Pro -Turn EV (Gravely, 2021), have 
batteries that can be exchanged.   
17 Table I -5. Professional SORE equipment and ZEE used in performance analysis. 
Type of 
equipment  Make and 
model of SORE 
equipment SORE 
equipment 
citation Make and model of ZEE  ZEE citation 
Chainsaw  Stihl MS -211 (Stihl USA, 
2020b) Greenworks 
Commercial GS 
181 (Greenworks, 
2021b) 
Generator Set  Honda 
EU7000iS  (Honda, 2020a)  Goal Zero 3000X  (Goal Zero, 2020a ) 
Lawn Mower  Honda 
HRC216HXA  (Honda, 2020b)  Greenworks GMS210  (Greenworks, 
2021c ) 
Leaf Blower / 
Vacuum  Husqvarna 967 14 43- 01 (Leaf Blowers Direct, 2020)  Stihl BGA 2 00 (Stihl USA, 2021b) 
Pressure Washer  Simpson 
SW4035HADM  (Pressure 
Washers 
Direct, 2020)  Pressure Pro 
EE3540A -AS + 
Goal Zero 
3000X  (Pressure 
Washers Direct, 
2021; Goal 
Zero, 2020a ) 
Pump < 2 hp  Honda GX -25 (Northern 
Tool and 
Equip ment, 
2020)  Milwaukee 
2771- 21 (Home Depot, 2020i)  
Riding Mower  John Deere 
Z920M  (John Deere, 2020)  Mean Green CXR-60  (Eco Equipment Supply, 2020)  
Snow Blower  Toro Power Max HD 928 (Toro, 2020)  Toro 39902  (Snow Blowers Direct, 2020)  
Trimmer/Edger/ Brush Cutters  Husqvarna 525LST  (Husqvarna, 2020a)  Husqvarna 536 LiLx (Husqvarna, 2020b)  
iii. Operational differences between SORE equipment and ZEE  
While ZEE can perform the same jobs as SORE equipment, there are differences in 
operator experience with the two types of equipment. Overall, the zero -emission versions 
of specific equipment types have been designed to mimic the user  experience of the 
SORE equipment, but there are differences in prepar ing equipment  for use. 
With ZEE, particularly for regular users, the timing of battery charging needs to be considered . For most professional users, it is assumed they will purchase sufficient 
batterie s for a typical day of use and will recharge the batteries overnight when not 
operating equipment. Users would need sufficient electrical service and outlets to run battery chargers overnight. Daily runtime can be extended without the purchase of extra batteries if recharging is possible.   
18 When operating SORE equipment, users must make regular trips to the gas station . The 
user must fill a  portable fuel container (PFC)  with gasoline and then pour the  gasoline in to 
the equipment fuel tank . For any two -stroke equipment,f the fuel must be mixed with oil in 
a specific (generally 50:1) ratio before adding fuel to the equipment. This adds time to 
preparing equipment for use.  These operations present numerous opportunities for fuel 
spillage, another source of excess ROG emissions from SORE.  
Starting the equipment can also be very different for SORE equipment and ZEE. All ZEE is push- button start. Sometimes ZEE is purposefully made with starting sequences that 
requires pressing certain buttons in a certain order to avoid accidental power up  (e.g., U.S. 
Consumer Safety Product Commission, 2021). SORE equipment is sometimes available 
with push- button start for a premium. Other SORE equipment has recoil start where the 
user must use a pull cord to physically start the eng ine. 
iv. Equipment lifetimes  
When a manufacturer certifies SORE for sale or lease for use or operation in California, it is  
required to choose  an emissions  durability period , which is the period that represents an 
engine’s useful life. Currently, emissions durability periods for SORE in California range 
from 50 to 1000 hours. The wide range in durability periods can come from various points 
of failure including piston ring failure, crank bearing failure, gasket degradation, and 
various carburetor issues. Since there are so many moving parts inside an internal 
combustion engine, the opportunity for failure is high.  
ZEE, in contrast, often  utilize electric motors. In general, these electric motors are either 
brushed or brushless direct current motors, with the bru shless motors being the newest 
and most preferred option. Electric motors do not have many moving parts. In general, this leads to significantly longer lifespans of the motors, with brushed electric motors operating between 1,000 and 3,000 hours depending on the material composition of the brushes ( Perzan , 2021; Janjua , 2017). Based on market reports, s taff expects the majority 
of new ZEE purchased to be battery -powered (Farnsworth Group , 2021) . The majority of 
battery- powered equipment utilizes brushless motors due to the increased efficiency and 
lifespan of the motors. Brushless motors can operate for tens of thousands of hours, 
                                            
f The complete combustion cycle of a two- stroke engine requires one up and one down movement of the 
piston within the cylinder during one crankshaft revolution. The complete combustion cycle of a four -stroke 
engine requires two up and two down movements of the piston within the cylinder during two crankshaft 
revolutions. A complete combustion cycle is the complete process of gasolin e and air being drawn into the 
cylinder, compressing the mixture, igniting it, and expelling the exhaust. Two -stroke engines have fewer 
moving parts than four- stroke engines and often have a higher power -to-weight ratio. Two -stroke engines 
require pre- mixing of fuel and oil, often referred to as premix, because they rely on the oil in the fuel -oil 
mixture to lubricate critical engine parts. Four- stroke engines do not require premix because the critical 
engine parts are either directly or splash lubricated. Two -stroke engines often have higher emissions than 
four- stroke engines of comparable power output due to the oil being burned in the engine as well as the 
presence of oil droplets in the exhaust. Consequently, particulate matter exhaust emission standards  
specified in § 2403 apply to two- stroke engines but not four -stroke engines.   
19 depending on the quality of the bearings that are used in the motor  (Perzan , 2021; Janjua , 
2017 ). Overall, electric motors provi de a service life that is significantly longer than  internal 
combustion engines.  
ZEE generally have  a longer limited warranty period than SORE equipment . For instance, 
Stihl offers limited warranties of three years for residential use and two years for 
professional use on all  of their battery equipment. For the gasoline -powered equipment, 
residential limited warranties range from one to two years. For professional gasoline-
powered equipment, limited warranties range from three months to two years (Stihl USA, 
2021a ). While the equipment evaluated for performance characteristics were  not chosen 
for their limited warranty period , in almost all cases the limited warranty period for  the 
electric equipment is at least as long as the limited warranty period  for the  SORE  
equipment , as shown in T ables  I-6 and I -7, below . These units are representative of the 
general trend that ZEE has longer warranty periods than SORE equipment. T he trimmers 
in Tables I -6 and I -7 show shorter warranties for the zero -emission version t han the SORE 
version . There are ZEE trimmers with longer warranties, including all Stihl battery- powered 
trimmers, which have the three- year warranty noted above, and all trimmers under the 
SCAQMD commercial lawn and garden equipment exchange program, whic h have a two -
year warranty (Shen, Walter, Personal Communication, August 11, 2021) . The zero -
emission pressure washer has a shorter motor warranty than the engine warranty on the 
SORE pressure washer ; both have five -year warranties on the pump.  
Exhaust and evaporative emission control system warranty periods are two  years for SORE 
equipment, regardless of the limited warranty period.  ZEE used to generate emission 
reduction credits must have a  minimum warranty period of two  years for the equipment , 
including batteries and battery chargers , as applicable.  
These limited warranty periods suggest that ZEE generally have  a longer lifetime than 
SORE  equipment . Using ZEE  can help users sa ve money on equipment  purchases over 
time, by extending the period b efore they purchas e replacement equipment.   
20 Table I -6. Residential SORE equipment and ZEE limited warranty periods . 
Type of 
equipment  Make and model of SORE 
equipment  SORE 
warranty 
period 
(years)  SORE 
equipment 
citation Make and model of 
ZEE ZEE 
warranty 
period  
(years)  ZEE citation  
Chainsaw  Ryobi RY 3716  3 (Home Depot, 2020l)  DEWALT DCCS670T1  3 (Home Depot, 2020d)  
Generator Set Briggs & Stratton #030744  2 (Home Depot, 2020b)  Goal Zero Yeti 1500  2 (Goal Zero, 2020b ) 
Lawn Mower  Troy-Bilt TB170 
XP Space Saver  3 (Home Depot, 2020c ) Ego LM2102SP  5 (Home Depot, 2020f)  
Leaf Blower/ 
Vacuum  Echo PB- 2520  5 (Home Depot, 2020e)  Ego LB6500  5 (Lowes, 2021a)  
Pressure Washer  Ryobi RY803001  3 (Home Depot, 2020m)  Sun Joe SPX4600  2 (Home Depot, 2020n)  
Pump <  2 hp GPT Co. XG10  1 (Lowes, 2021b)  RYOBI P750- P163  3 (Home Depot, 2020k)  
Riding Mower  John Deere BG21077  2 (Home Depot, 2020h)  RYOBI -
RY48140  3 (Home Depot, 2021 a) 
Snow Blower  Briggs & Stratton #1697099  3 (Home Depot, 2020a)  Greenworks SN200  3 (Home Depot, 2020g)  
Trimmer / 
Edger/Brush Cutter  Toro 51978  4 (Home Depot, 2020o)  Milwaukee 2825- 21ST  3 (Home Depot, 2021b)  
21 Table I -7. Professional SORE equipment and ZEE limited warranty periods . 
Type of 
equipment  Make and model of SORE equipment  SORE 
warranty 
period 
(years)  SORE 
equipment citation Make and model of ZEE ZEE 
warranty 
period  
(years)  ZEE citation  
Chainsaw  Stihl MS -211 0.25 (Stihl USA, 
2020b)  Greenworks Commercial GS 181  2 (Greenworks , 
2021b) 
Generator Set Honda EU7000iS  3 (Honda, 2020a)  Goal Zero 3000X  2 (Goal Zero, 2020a ) 
Lawn Mower  Honda HRC216HXA  1 (Honda, 2020b)  Greenworks GMS210  2 (Greenworks, 
2021c ) 
Leaf Blower / 
Vacuum  Husqvarna 967 14 43- 01 0.25 (Leaf Blowers Direct, 2020)  Stihl BGA  
100 2 (Stihl USA, 2020a)  
Pressure Washer  Simpson SW4035HADM  3 (Pressure Washers Direct, 2020)  Pressure Pro EE3540A -
AS  1 (Pressure Washers Direct, 202 1) 
Pump < 2 hp  Honda GX- 25 1 (Northern Tool and Equip ment, 
2020)  Milwaukee 2771- 21 5 (Home Depot, 2020i)  
Riding Mower  John Deere Z920M  3 (John Deere, 2020)  Mean Green CXR-60  2 (Eco Equipment Supply, 2020)  
Snow Blower  Toro Power Max HD 928  45 days  (Toro, 2020)  Toro 39902  2 (Snow Blowers Direct, 2020)  
Trimmer / 
Edger/Brush Cutter  Husqvarna 525LST  2 (Husqvarna, 2020a)  Husqvarna 536 LiLx 1 (Husqvarna, 2020b)   
22 3. Potential Challenges for ZEE Deployment  
Manufacturers currently produce zero- emission landscaping equipment for residential 
and professional users.  However, as described in this section, some  professional and 
residential users are reluctant to purchase ZEE . These users may not choose to 
purchase ZEE as long as new SORE equipment are  available in California . In addi tion, 
there is still a need for innovation and growth in the zero- emission generator  market. 
Allowing certification of only zero- emission generators beginning with MY 2024 could 
have unintended negative impacts on backup power supply in some regions of 
California. A regulation that accelerates the adoption of  ZEE, while allowing more time 
and incentives for generators to meet the zero -emission standard , can be the driving 
force that helps users embrace the new technology and provides the emission 
reducti ons that are expected under the 2016 State SIP Strategy.  
a. Consumer Behavior  
Some users continue to purchase SORE equipment rather than ZEE . Studies by The 
Farnsworth Group indicate that ZEE accounted for more of the small off -road 
equipment purchased by  residential users and landscapers in 2020 than in previous 
years  (Farnsworth Group , 2021a and 2021b) . Twenty -seven percent of surveyed 
landscapers’ purchases were ZEE in 2020, versus 21 percent in 2018. Three major factors cited for  consumer behavior as i t pertains to small off -road equipment 
purchase decision are the upfront cost, run -time, and user habit  (CSUF SSRC, 2019) .  
Residential survey  respondents who noted that they had no plans to purchase new 
equipment in the next year were asked what factors would be important in a hypothetical purchase in deciding between gasoline- powered equipment and ZEE. 
Cost was the top response, followed closely by power and time to refuel/recharge. These results suggest  that many individuals base their purchase decisions on old 
information. Currently, residential SORE equipment and ZEE have similar price s. In 
many cases, ZEE cost  less to purchase. Section VII.A .2 and section C.1.c.i of  Appendix 
I of this Staff Report  discuss residential and professional  SORE equipment and ZEE 
pricing . ZEE manufacturers market their equipment as having performance that is 
comparable to or better than  SORE in many cases.  
The CSUF survey asked participating landscapers what qualities of the equipment 
were most important to them, t o better understand landscapers’ rate of adoption of 
ZEE. Performance, run -time, and cost were the top three responses. T he average 
purchase price of pro fessional ZEE , including sufficient batteries for an eight -hour 
workday,  is higher than for SORE equipment . As an example, the purchase price of  a 
professional ZEE leaf blower  with batteries  is nearly twice as much as its gasoline 
counterpart. Upfront cost is a significant barrier to transforming the population of lawn and garden equipment in the professional market to ZEE, even though ZEE often ha ve 
a lower total cost of ownership over the equipment lifetime. D ecreasing battery prices 
may result in lower prices for ZEE ( Martin 2019 ), as discussed further in section I.E.3.b . 
ZEE do not have m any of the inconveniences of gasoline- powered equipment , listed in 
I.E.2.a.iii. ZEE are quieter and requir e little maintenance. C harging costs less  than  
23 purchasing gasoline ( Mahoney,  2021) . Section C.1.d.i of Appendix I  includes a 
discussion of fuel and electricity costs. 
Professional landscapers and  residential users with large properties require  ZEE with a 
longer run time or must purchase additional batteries  to complete their typical work  
day. Some of  these users who currently use SORE equipment  may purchase diesel or 
large spark -ignition (LSI) engine equipment rather than  SORE or ZEE equipment  when 
replaci ng their SORE equipment . However, t his is not a likely pathway as diesel 
equipment are much more expensive than similar SORE equipment and do not offer 
the full  operational  cost-savings that ZEE  offer . For example, the price of a Generac 
XD5000E, which is a popular diesel generator, is $ 4,230.42 (Generac, 2021).g This is 
much higher than the price of the residential  SORE  generator  in Table I-4 , $861.49  
(Home Depot, 2020b).  The price  of the residential zero -emission generator in Table I-4 
is $2,169.95 (Goal Zero, 2020b), which is lower than the price  of the Generac XD5000E  
diesel generator.  The price of th is diesel generator is approximately 4 times  the price  
of the residential SORE generator and 2 times the price of the  zero-emission 
generator. T his cost difference would  be significant for most consumers.  Reported 
production of small off -road diesel engines rated at or below 19 kW for California is 
approximately one tenth of the production of SORE for California. Manufacturers of 
diesel generators would need to significantly increase production volumes in order to 
meet demand from customers who would otherwise purchase SORE generators.  CARB 
staff plans to propose amendments to the current emission standards for off -road 
diesel engines around 2024 a nd may at the same time include provisions encouraging 
or requiring ZEE for some diesel applications.  
For riding lawn mowers, both diesel and LSI options are available. LSI versions of 
riding mowers are generally less expensive than diesel . A user who want s to purchase  
a riding mower but do es not want to purchase ZEE is more likely to purchase an LSI 
engine riding mower as it is less expensive than a diesel engine riding mower . A 
popular LSI riding mower is the Cub Cadet PRO Z 972 L KW, which has a price of  
$12,899 (Holmes Rentals and Sales, 2021) . This price is higher  than the price of the  
commercial SORE riding mower in Table I-5 at $10,449 . The price increase associated 
with purchasing  an LSI engine riding mower  instead of  a SORE riding mower  is smaller 
than for a zero -emission riding mower, but an LSI engine riding mower does not offer 
the operational savings a zero- emission mower would offer . It is important to note that 
per EO N-79-20 (California Executive Order No. N -79-20, 2020), CARB staf f will be 
looking for ways to encourage or require the maximum use of zero -emission 
equipment where feasible, including in categories where manufacturers currently sell LSI versions . 
While purchasing  additional batteries would add to the upfront cost, a pr ofessional  
user could  still experience operational cost -savings. Many manufacturers sell 
equipment bundles that include multiple batteries and a quick charger that can charge 
                                            
g Prices in this paragraph include sales tax.   
24 one battery about as quickly as a user can discharge another battery.  Residential -
grade ZEE generally come with a battery that can last long enough for the average 
user to conduct the job at hand  (Mahoney, 2021; Yardcare.com, 2020 ). 
b.  More Time Needed for  Generators  to Meet Zero-Emission Standard s  
Generators are fundamentally different from other SORE equipment  because their 
purpose is to generate electricity. Because their function is to provide electrical power 
rather than perform mechanical work (as lawn and garden equipment does) , zero -
emission generators often convert chem ical energy to electrical energy without the 
use of an electric motor. Most zero -emission generators are essentially battery banks 
with a built -in power inverter. S ome models  have the ability to accept solar panels for 
charging . Hydrogen fuel cell powered generators have also been introduced  in the 
market and could become more prevalent . For purposes of this report, we refer to all 
of these SORE alternatives as zero- emission generators . 
In 2020, g enerators accounted  for 1 4 percent of the total population  of SORE 
equipment, and 19 percent of all NO x and ROG  emissions from SORE (CARB, 2020).  
Residential users own 89 percent of SORE generators and, on average,  use them more 
than other small off -road equipment . Per the CSUF survey, only 14 percent of 
resident ial generators and 11 percent of generators owned by nonlandscaping 
businesses are currently zero- emission generators, much lower than most other 
equipment types. Z ero-emission generators will need to m ake up a much larger 
market share  to achieve substantial emission reductions from generators. Regulatory 
amendments are needed to accelerate the deployment  of zero- emission generators in 
California.  
Zero- emission generators can serve the needs of users. T he Goal Zero Yeti 6000X is 
one of the highest energy storage portable  zero-emission generators that is widely 
available. It has 6,071 watt -hours of energy storage and can run a full -size refrigerator 
for 110 hours or a circular saw for 4 hours. Solar  panels can extend the runtime (Goal 
Zero, 2021d). Some  zero-emission generators have  greater energy storage and more 
capability. The Onyx Rhino has 7,600 watt -hours of energy storage and is equipped 
with both 120- volt and 240- volt 50 or 60  hertz output. The Onyx Rhino can run a 
refrigerator for 3 to 4 days, charge a laptop over 100 times, or charge a 20- volt power 
drill over 150 times (Onyx, 2021).  
For users who require even more power, such as contractors, mobile power units are 
available. For example, FreeWire Tech currently produces a mobile power unit, the 
Mobi Gen, which has 80 kilo watt- hours of energy storage, and a rated power output 
of 11  kilowatts (FreeWire Tech, 2021) . Zero- emission generators of this size have 
higher prices than SORE generators; however, incentive programs such as the Clean Off-Road Equipment Voucher Incentive Project  (CORE ) exist to help mitigate the cost 
of these generators (California CORE, 2021) . Additionally, new vehicle models such as  
the Ford F- 150 Lightning pickup truck allow use of electricity from batteries powering 
the vehicles to power other equipment. The F- 150 Lightning has  90 kilowatt- hours of 
energy storage , which can be used to provide backup power to a home. The F- 150  
25 Lightning can also use the 90 kilo watt- hour battery to deliver up to 9,600 watts of 120-
volt power to  items plugged directly into the vehicle (Ford  Motor Company, Inc. , 
2021).  
Even so, for the reasons described in the following paragraphs, CARB staff 
recommends allowing more time and  implementing a new credit program for 
manufacturers to innovate and develop new products  to meet the future  demands of 
the zero -emission generator market. Manufacturers will need to overcome several 
challenges  to increase the share of zero -emission generators :  
• Limited options  are currently available, and they often have  higher costs . As 
shown in A ppendix I, a popular SORE  generator, the Briggs & Stratton 
#030744, costs $861.49 (Home Depot , 2020b).  A zero- emission generator with 
similar characteristics , the Goal Zero Yeti 1500, costs $2, 169.95 (Goal Zero, 
2020b). The $1,308. 46 price differential  would be difficult to recoup without 
significantly increased use. Section  C.1.d  of Appendix I includes a discussion of 
operating costs.  As the cost of batteries decreases (Martin 2019), the price  of 
zero-emission generators is also expected to  decrease .  
• Current supply  might not meet  future demand . While the existing zero -emission 
generators can adequately power essential equipment and appliances in 
residences, manufacturers of zero -emission generators may not be positioned 
to meet  the market demand that could occur if fewer SORE generators were 
produced starting in MY 2024. P opulation modelling with SORE2020 suggests 
demand for generators is relatively constant, year over year. Requiring  MY 2024 
generators to meet emission standards of zero could increase the price of available zero- emission generators due to demand. A price increase would 
create added costs for residential users and professional users. U sers may not 
recoup such additional costs through  operating cost- savings with zero-emission 
generators. The break -even point for typical residents purchasing a zero -
emission generator instead of SORE at current prices is 9 years. If the price of ZEE increased, that time would be extended. S ection s C.2, C.3, and C.5 of 
Appendix I include break -even time calculations. Thus, the market is not ready 
to replace the remaining SORE generators  with zero- emission generators by MY 
2024. 
• Options for  non-grid recharging  of zero- emission generators are costly . 
Batteries can be charged  on the g rid, if available, or through local solar or wind 
power generation. S olar panels  and wind turbines can have significant cost . For 
instance, Goal Zero sells kits with zero -emission generators and solar panels. A 
low cost version with a Goal Zero Yeti 200X power station and Nomad 20 solar panel costs $449.90 (Goal Zero, 2021b). The Goal Zero Yeti 200X power station 
by itself costs $299.95 (Goal Zero, 2021c). The Goal Zero Yeti with the greatest 
energy storage is the 6000X, which costs $4,999.95 (Goal Zero, 2021d ), while 
with 4 Nomad 200 Solar Kit s, the cost is $7,350.5 2 (Goal Zero, 2021b).  Fuel cell 
generators can be run for as long as there is fuel present, much like a SORE 
generator . The cost of a fuel cell can be significant (Patel, 2020) . Fuel cells  
26 usually use a methanol reformer to produce  hydrogen. Methanol in California is 
currently available for $3.85 per gallon  (Altergy 2021, personal communication , 
May 24, 2021), which is similar to the price of gasoline.  
• The zero -emission generator market needs mo re time to mature to  better meet  
demand for backup  power supply . In some  regions of the state, public safety 
power shutoffs (PSPS) occur during  periods of increased fire danger. E lectric 
utilities have announced efforts to reduce the number  and duration of PSPS  
events. These include increasing utilization of microgrids and transmission line 
switches that allow for very localized PSPS (Pacific Gas & Electric, 2020). PSPS 
were less frequent and had a shorter duration on average in 2020 than in 2019 (California Public Utilities Commission , 2021).  CARB staff recommends 
implementing emission standards of zero for generators starting in MY  2028 to 
allow more time for the zero -emission generator market to mature . 
The price of zero -emission generators per unit of energy storage will likely decrease 
over time  as the cost of batteries decreases . Projections suggest  that, from 2010 to 
2030, the price of a battery holding a kilowatt- hour of energy will decrease by over 90 
percent (Martin, 2019). CARB staff expect s that generator manufacturers will be able 
to offer zero- emission generators at a price and capability comparable to existing 
SORE generators by MY 2028 and  that, as the market matures, the overall supply of 
zero- emission generators will increase to meet the dema nd. CARB staff further 
anticipates  the proposed zero -emission generator  credit program will accelerate the 
production  of more, and a greater variety of, zero -emission generators.  
F. Additional Strategies for Transition to ZEE  
CARB staff has  pursued several strategies to support increased adoption of  
zero- emission technologies. One such strategy was running ZEE demonstration 
projects with state agencies. The landscaping crew at Capital Park in Sacramento, several California Department of Tran sportation crews, and the landscapers at 
California State University Sacramento were all able to try a full suite of ZEE from several manufacturers. These demonstration projects were run  in conjunction with the 
manufacturers, who supplied the equipment.  
Staff also met with personnel from the Department of General Services through these 
demonstration projects, and provided input for updates to the State Administrative Manual (SAM). Recommended updates, which included adding sweeping and raking 
as preferred methods for exterior maintenance,  were incorporated in the SAM in 
November 2018 (California  Department of General Services, 201 9). The updated SAM 
requires that when sweeping or raking are not possible, electric equipment must be used, unless there are comp elling circumstances and prior authorization is received 
from facilities management. The updates to the SAM also require state departments to replace their gasoline- powered equipment with zero- emission strategies,  as 
replacement schedules allow.   
27 Since 2018, s taff has conducted a program to reach more landscaping groups with 
information about ZEE and an opportunity to try the equipment. The ZEE Roadshow is 
a demonstration project, with a trailer filled with eight brands of ZEE for professional 
users. The Roadshow has visited California landscaping crews at locations including cities, school districts, colleges, theme parks, and zoos. Further discussion of the ZEE Roadshow can be found in section X.E. 
Several programs provide incentive funding for professional  and residential users to 
purchase ZEE. These programs are an important complement to the P roposed 
Amendments. CARB manages a broad portfolio of incentives that collectively help 
achieve CARB’s emission reduction goals, including  greenhouse gas (GHG) reductions. 
This includes programs such as the Carl Moyer Memorial Air Quality Standards Attainment Program (Carl Moyer Program) and Community Air Protection Incentives Program. The Carl Moyer Program provides funding opportunities for early and extra cost-effective emission reductions that can be credited towards California’s SIP 
commitments. The Community Air Protection Incentives Program includes funding to 
support early actions for emission reductions in communities most heavily impacted by 
disproportio nate levels of air pollution.  Finally, the Clean Mobility in Schools Pilot 
Project included funding for zero -emission landscaping equipment. Three schools 
were awarded funding and one has already purchased ZEE.  
Several air districts, including SCAQMD and SJVAPCD, have existing incentive programs for landscapers. These programs allow landscapers to trade in their existing SORE equipment and obtain  a substantial rebate or discount on their purchase of ZEE 
(SCAQMD, 2021 ; SJVAPCD, 2021). Both the Bay Area Air Q uality Management 
District (BAAQMD) and Santa Barbara Air Pollution Control District (SBAPCD) also offered  incentive programs for professional landscapers. D ue to the overwhelming 
response to  these programs, they have exhausted all available funding (BAAQM D, 
2021; SBAPCD, 2021).  Many districts offer incentives on residential equipment, as 
well. 
II. The Problem That the Proposal Is Intended t o Address  
This chapter provides a description of the problems that the Proposed Amendments to the SORE  exhaust and evaporative regulations and the certification and test 
procedures are intended to address, along with descriptions of how the Proposed Amendments would resolve the problems. Chapter  XI provides detailed descriptions 
of the underlying purpose and rationale for  each specific proposed amendment . 
Appendices A through G provide the full text of the P roposed Amendments . 
A. Current SORE Regulations Will Not Achieve Required Emission Reductions  
1. The Problem  
HSC, section 39602.5 (a) provides that CARB must “adopt rule s and regulations 
pursuant to Section 43013 that  … will achieve ambient air quality standards required 
by the federal Clean Air Act … in all areas of the state by the applicable attainment  
28 date, and to maintain these standards thereafter.  Under  HSC, sectio n 39602.5(b), t he 
state board shall adopt these  measures if they are necessary, technologically feasible, 
and cost effective, consistent with Section 43013.”  CARB must also “adopt and 
enforce rules and regulations that anticipate the development of new technologies or the improvement of existing technologies” if they are necessary to carry out CARB’s duties to achieve attainment of ambient air quality standards  (HSC, section 
39602.5(b)) . Substantial progress has been achieved in reducing  NO
x and ROG  
emissi ons through implementation of CARB’s existing mobile source programs. M any 
of these programs will continue to provide further reductions through 2031, 
contributing significantly to meeting ambient  air quality standards.  However, about 12 
million California ns live in communities that still exceed the ozone and PM 2.5 NAAQS  
(CARB , 2017b) . Substantial challenges still remain in meeting the ozone standards in 
two areas of the state with the worst air quality issues: the South Coast Air Basin and 
the San Joaquin Valley Air Basin. Mobile sources and the fossil fuels that power them 
are the largest contributors to the formation of ozone and PM 2.5 in California.  
Consequently, as described in Chapter  I, the 2016 State SIP Strategy calls for 
substantial emission reductions from both stationary and mobile sources, including SORE . SORE use leads to significant emissions of NO
x and ROG , which contribute to 
PM and ozone formation. The 2016 State  SIP Strategy contains expected statewide 
emission reductions for SORE of  4 tpd  of NO x and 36 tpd  of ROG , by 2031  (CARB , 
2017b) . Expected emission reductions in 2031 from SORE included in t he 2016 State 
SIP Strategy in 1) the  South Coast Air Basin  are 2 tpd of NO x and 16 tpd of ROG,  and 
2) in the San Joaquin Valley Air Basin are  0.3 tpd  of NO x (CARB , 2017b) . 
Current SORE regulations will not achieve emission reductions expected under  the 
2016 State SIP Strategy. As described  in greater detail in  section I II.A.3 , the 
population of ZEE  in California has increased  in recent years. The increase is expected 
to continue as the total population of small off -road equipment grows (CARB, 2020).  
Even so, the growth in ZEE sales will be insufficient to maximize the reduction of SORE  
emissions without further regulation (CARB, 2020) . SORE emissions are still expected 
to increase  in the 2020s as California’s population continues to grow. As shown in 
Figure II -1, during summer months (May through October), NO x emissions from SORE 
in 2021 are 17.0 tpd and are expected to increase 8 percent to 18.3 tpd by 2031.  ROG 
emissions from SORE are currently 123.8 tpd and expected to increase 3 percent to 
127.5 tpd by 2031  (CARB,  2020) .  
The 2016 State SIP Strategy calls for more stringent emission standards and additional 
regulatory incentives to accelerate the replacement of SORE equipment with ZEE. 
More stringent emission standards and additional regulatory incentives  would  prevent 
SORE emissions from increasing and facilitate  emission reductions necessary to attain  
ambient air quality standards by 2031 and protect the health and welfare of all 
California resident s. Replacing new sales of SORE  equipment with ZEE as quickly as 
feasible will help California  maximize emission reductions from SORE and  meet its 
obligations under the 2016 State SIP Strategy.  Amendments to the SORE regulations 
are necessary to accomplish these actions.    
29 Figure II -1. Summer  average  NO x and ROG  emissions under current SORE 
regulations. 
 
Exhaust emission standards for SORE have not been changed since MY s 2000 to 2008 , 
depending on displacement category , despite improvements in available emission 
control technologies. In fact, among engines currently available for sale in California, 
there are many engine families certified below the current emission standards.  
Manufacturers use emission credits generated  by engine families that are certified to 
levels below the current emission  standards to offset emissions from engine families 
that are certified to levels above the current standard.  
There are two paths to engine certification for evaporative emissions  – design and 
performance. Manufacturers using design certification  must use evaporative emission 
control system components  that meet design  standards . For performance certification, 
manufacturers  must test emissions from the complete  engine  (with the evaporative 
emission control system installed) . The majority of evaporative families use design 
certification. Among those evaporative families using performance certification, there are several families that emit well below the current emission standard s, 
demon strating  that overall lower emissions from SORE are possible.  
Engines with displacement less than or equal to 80 cc comply by using fuel tanks and 
fuel lines that meet the emission standards listed  in Table I- 3. There is no performance 
certification option  for engines in this displacement category.  
Beginning with MY  2024, the Proposed Amendments would  require all SORE to use 
performance certification. E vaporative emission standards for MYs 2024 through  2027 
for engines used in generators would  be more strin gent than the current emission 
standards . Evaporative emission standards for all other SORE would  be zero. To 
 
30 ensure that engines meet the more stringent emission standards for generators, 
performance certification is necessary. Manufacturers would also need to use 
performance certification to determine the amount of credits needed to offset 
emissions from SORE categories  for which emission standards are zero.  
Current compliance testing of evaporative families shows low rates of compliance 
(CARB , 2021f ; Figure  II-2). Of the 31 evaporative families tested by CARB  between 
MYs 2015 and 2019 , 12 have failed. This 39 percent  failure rate results in much higher 
ROG emissions from SORE and highlights the need to adopt  zero- emission 
technologies as quickly as possible. Prior to MY 2020 , only SORE that were  
performance certified were  required to meet a diurnal emission standard in 
compliance testing. This means engines are failing compliance testing, despite being 
tested under the same conditions as certification  testing conditions. This suggests 
poor  quality control of SORE evaporative emission control systems .  
Generators, in particular, present a unique issue for emission reductions. The function 
of generators is to produce electricity when grid electricity is not available, so 
zero- emission generators must have significant battery capacity or be able to generate 
electricity through use of solar energy , wind energy , or a fuel cell . However, reducing 
emissions from generators is vital. In 202 0, generators were the single largest NO x and 
ROG  emission source in the SORE category, accounting for 19.3 percent of the total 
of NO x and ROG  emissions from SORE  (CARB, 2020). Therefore, the Proposed 
Amendments include more stringent emission standards for engines used exclusively 
in generators for MY 2024 and subsequent model years. 
Figure II -2. Evaporative emission  compliance testing  results for MYs 2015 -2019. 
 
 
31 2. The Solution  
To address these problems, CARB staff proposes regulatory amendments to the SORE 
regulation s to accelerate the replacement of new SORE  equipment  produced for sale 
or lease for use or operation in California with ZEE. This will be achieved by setting 
SORE emission standards to zero and by refining and expanding existing emission 
reduction credit programs for manufacturers to further incentivize ZEE . Currently, 
most  ZEE are either battery- powered or corded electric equipment. In addition to 
charging battery storage using grid electricity, f uel cells and solar or wind generation 
could be used directly to power electric equipment in place of engines subject to the 
SORE regulations.  
a. Amend Emission Standards  
The Proposed Amendments, as summarized in Chapter XI and provided in full  in 
Appendices  A through G, include two phases for tightening the emission standards. 
First, for MY 2024, HC and NO x exhaust emission standards and evaporative emission 
standards would  be zero for engines used in all new small off -road equipment types 
produced for sale or lease  for use or operation  in California except g enerators. 
Generator emission standards would be more stringent starting with MY  2024 but 
would not be zero. The second phase would  be implemented  starting with MY  2028, 
when the emission standards for  new generators  manufactured for sale or lease for 
use or operation  in California  would  be zero.  
These emission standards would  maximize emission reductions as statutorily required  
of CARB , help meet the expect ed emission reductions for SORE  in the 2016 State SIP 
Strategy and move close to the zero- emission goals for small off -road equipment 
identified in EO N-79-20, noted in section I.A of this Staff Report. Under the Proposed 
Amendments scenario , it is projected that 93 .4 percent  of equipment subject to the 
SORE regulations would  be ZEE in 2035 (CARB, 2020). Figure II- 3 shows the modeled 
growth of ZEE as a portion of small -off road equipment under the Proposed 
Amendments. Some  equipment is kept in use for many years, so replacing the 
remaining SORE equipment with ZEE would  take many additional years. However,  
99.4 percent  of equipment subject to the SORE regulations would be  ZEE in  2043.   
32 Figure II -3. Modeled small off -road equipment population statewide under  the 
Proposed Amendments . 
 
The Proposed Amendments would allow more  time for generators to meet emission 
standard s of zero for two reasons. First, one of the main uses of generators is backup  
power supply. In some  regions of the state, PSPS have become a n occasional  
occurrence due to periods of high wind and low humidity events that increase  fire risk. 
It is not the intention of the Proposed Amendments to reduce options for backup  
power supply in these regions, so a delay in the time for generators to be zero -
emissions  is reasonable. Second, as described in section I.E.3 .b, there is still a need for 
innovation and growth in the zero- emission generator  market. The fraction of all 
generators currently in use  that are ZEE is significantly lower than  that for lawn and 
garden equipment , such as  lawnmowers and trimmers.  
Professional users’ generator use varies by industry. Professional -grade zero -emission 
generator options are currently limited and have a higher cost  than their SORE 
counterparts.  Reducing emission standards for generators in two phases and over a 
longer period  than other small off -road equipment allow s time for the market to 
mature. A proposed zero -emission generator credit program provide s manufacturer 
flexibility and send a market signal to encourage growth in the zero -emission 
generator market.   
Under the Proposed Amendments, beginnin g with MY  2024, the evaporative emission 
standards would  cover a greater portion of an engine’s evaporative emissions. This 
would  ensure MY 2024 and subsequent model year  SORE  equipment meet the 
emission standards. Currently, the evaporative emission standards only apply to the 
24-hour diurnal cycle, while under the Proposed Amendments they would also apply 
to the hot soak period.  The evaporative test procedure  includes running the 
 
33 equipment for fifteen  minutes to heat the engine.  Then the hot soak period o ccurs , 
which  involves holding the equipment  at 95 degrees for one hour. Section XI.B has 
further description of the hot soak and diurnal test procedures.  Manufacturers are 
already required to measure and report hot soak emissions when performing a test on 
a complete engine, so including hot soak emissions would  not add any testing burden 
or cost. This change would  reduc e the potential for higher -than-expected hot soak 
emissions to reduce the actual benefits of the  emission standards.  
The Proposed Amendments include hot soak plus diurnal evaporative emission 
standards for generators for MY s 2024 through 2027 that are approximately 
50 percent lower than current diurnal emission standards. Currently -certified engines 
meet  these emission standards, including the hot soak. S everal evaporative  families in 
each displacement category meet the proposed emission standards. T hese 
evaporative families  include engines used in all major SORE equipment types, 
including generators. The hot soak plus diurnal emission standards would  apply to 
engines with displacement less than or equal to  80 cc , which are currently required to 
meet permeation emission standard s for fuel tanks and fuel lines. The 0.50 -gram 
organic material hydrocarbon equivalent per test emission standard for engines with 
displacement less than or equal to  80 cc  was developed through testing conducted at 
CARB, which found engines for sale in California already exhibit hot soak plus diurnal emissions below this level. The permeation emission standards currently in effect for engines with displacement  less than or equal to  80 cc  would  be phased out for 
engines produced after MY 2023.  
Tables II- 1 and II -2 compare  current and proposed emission standards for exhaust and 
evaporative emissi ons, respectively. The proposed  HC + NO
x exhaust emission 
standard for the displacement category of greater than  825 cc would  align with the 
current exhaust emission standard for LSI engines, i.e., those rated greater than 
19 kilowatts (kW) and with displa cement greater than  825 cc .  
New emission standards for all SORE would apply beginning with MY 2024 to provide sufficient lead time to permit the development of the necessary technology giving appropriate consideration to the cost of compliance within that time period, as 
required by Section 209 of the Clean Air Act. This will provide at least two years for manufacturers to meet the emission standards, including preparing the necessary 
compliance demonstrations, which is sufficient where the technology to meet the emission standards  is used in equipment  already in the market. Implementing the 
proposed emission standards beginning in two years will result in significant emission reductions and progress in meeting the goals of  EO N-79-20 without imposing an 
undue burden or cost for compliance. Considering the requirements, implementing the emission standards earlier than two years does not provide adequate 
consideration for the costs.  
The Proposed Amendments would  also sunset the voluntary “Blue Sky Standards” for 
engines produced after  MY 2023. The Blue Sky Standards were developed to allow 
manufacturers to receive recognition for certifying to lower emission standards, but  
34 CARB has no record of any manufacturer taking  advantage of the program for 
engines.  
Table II -1. Current SORE  exhaust  emission standards and exhaust emission 
standards under the Proposed Amendments. 
Displacement  
category Current  HC + NO x 
emission standard  
(g·kWh-1)  Proposed HC + 
NO x emission 
standardh for 
MY 2024- 2027 
generators  
(g·kWh-1)  Proposed HC + 
NO x emission 
standard for all 
other SORE for 
MYs 2024 and 
later 
(g·kWh-1) 
< 50 cc  50 6.0 0.00 
50-80 cc, inclusive  72 6.0 0.00 
> 80 cc - < 225 cc  10.0 6.0 0.00 
225-825 cc, inclusive  8.0 3.0 0.00 
> 825 cc  8.0 0.80 0.00 
                                            
h For MY 2028 and subsequent model years, the proposed exhaust emission standard s for generators 
are 0.00 g·kWh-1 for HC + NO x.  
35 Table II -2. Current SORE evaporative emission standards and evaporative 
emission standards under the Proposed Amendments. 
Displacement  
category Current diurnal 
emission standard  
(g·day-1) Proposed hot s oak 
plus diurnal 
emission standardi 
for MY 2024- 2027 
generators  
(g·test-1) Proposed h ot soak 
plus diurnal 
emission standard 
for all other SORE 
for MYs 2024 and 
later 
(g·test-1) 
≤ 80 cc  N/A 0.50 0.00 
> 80 cc - < 225 cc 
except walk-
behind mowers  0.95 + 0.056 × nominal capacity 
(liters)  0.60 0.00 
> 80 cc - < 225 cc 
walk-behind 
mowers  1.0 N/A 0.00 
≥ 225 cc  1.20 + 0.056 × 
nominal capacity 
(liters)  0.70 0.00 
The Proposed Amendments include revisions to the following SORE regulation s: 
• Amend CCR §§ 2400, 2401 , 2402, 24 03, 2404, 2405,  2405.1,  2405.2, 2405.3, 
2406, 2407, 2408, 2408.1,  2750, 2752, 2753, 2754, 2754.1, 2754.2,  2755, 2756, 
2757, 2758, 2759, 2761,  2762,  2763, 2764, 2765, 2766, 2767, 2767.1,  and 2771  
• Adopt CCR  §§ 2408.2 and  2754.3  
• Repeal CCR § 2768  
To provide consistency with the proposed changes to the emission standards, the 
Proposed Amendments also include revisions to the test  and certification  procedures 
included in the above SORE regulation s and in the following procedures inc orporated 
by reference:  
• CARB . Small Off -Road Engine Evaporative Emissions Test Procedure, TP -901, 
Test Procedure for Determining Permeation Emissions from Small Off -Road 
Engine Fuel Tanks. Adopted July 26, 2004, and last amended [insert 
amendment date].  
                                            
i For MY 2028 and subsequent model years, the proposed evaporative emission standard s for 
generators are 0.00 g·test-1.  
36 • CARB . Small Off -Road Engine Evaporative Emissions Test Procedure, TP -902, 
Test Procedure for Determining Evaporative Emissions from Small Off -Road 
Engines. Adopted July 26, 2004, and last amended [insert amendment date].  
• CARB . Small Off -Road Engine Evaporati ve Emission Control System 
Certification Procedure, CP -902, Certification Procedure for Evaporative 
Emission Control Systems on Small Off -Road Engines . Adopted July 26, 2004, 
and last amended [insert amendment date].  
• CARB . California Exhaust Emission Standards and Test Procedures for New 
2013 and Later Small Off -Road Engines ; Engine -Testing Procedures (Part 1054) . 
Adopted October 25, 2012, and last amended [insert amendment date].  
• CARB . California Exhaust Emission Standards and Test Procedures for New 
2013 and Later Small Off -Road Engines ; Engine -Testing Procedures (Part 1065) . 
Adopted October 25, 2012, and last amended [insert amendment date].  
The above listed documents are also being amended by this proposed regulatory 
action ; thus, the “insert amendment date” would be the date that the regulation is 
adopted by CARB.  
The Proposed Amendments incorporate by reference the following documents that 
were not previously incorporated : 
• American National Standards Institute, Inc. ( ANSI )/Nation al Electrical 
Manufacturers Association (NEMA) . 2016. ANSI/NEMA WD 6 -2016, Wiring 
Devices - Dimensional Specifications. ANSI Approval Date:  February  11, 2016.  
• American National Standards Institute, Inc.  (ANSI )/Outdoor Power Equipment 
Institute (OPEI) . 2018 . ANSI/OPEI B71.10- 2018 , American National Standard for 
Off-Road Ground -Supported Outdoor Power Equipment – Gasoline Fuel 
Systems – Performance Specifications and Test Procedures. Published 
November 12, 2018.  
• ASTM International ( ASTM ). 1995.  D2986 – 95a, Standard Practice for 
Evaluation of Air Assay Media by the Monodisperse DOP (Dioctyl Phthalate) Smoke Test . Approved September 10, 1995 . 
• ASTM. 2009. F1471 – 09, Standard Test Method for Air Cleaning Performance 
of a High -Efficiency Particulate Air Filter System. A pproved March 1, 2009 . 
• ASTM. 2010. D5291 – 10, Standard Test Methods for Instrumental 
Determination of Carbon, Hydrogen, and Nitrogen in Petroleum Products and Lubricants. A pproved May 1, 2010. 
• ASTM. 2010. D5599 – 00 (Reapproved 2010) , Standard Test Method for 
Determination of Oxygenates in Gasoline by Gas Chromatography and Oxygen 
Selective Flame Ionization Detection. A pproved October 1, 2010 .   
37 • ASTM . 2012.  D4629 – 12, Standard Test Method for Trace Nitrogen in Liquid 
Petroleum Hydrocarbons by Syringe/Inlet Oxidative Combustion and 
Chemiluminescence Detection. A pproved April 15, 2012 . 
• ASTM . 2012.  D5762 – 12, Standard Test Method for Nitrogen in Petroleum and 
Petroleum Products by Boat- Inlet Chemiluminescence. A pproved 
April  15, 2012. 
• ASTM . 2012.  D6348 – 12ε1, Standard Test Method for Determination of 
Gaseous Compounds by Extractive Direct Interface Fourier Transform Infrared 
(FTIR)  Spectroscopy. A pproved February 1, 2012. 
• ASTM . 2020.  D1835 – 20, Standard Specification for Liquefied Petroleum (LP) 
Gases. A pproved May 1, 2020 . 
• CARB. 2012. California 2001 t hrough 2014 Model Criteria Pollutant Exhaust 
Emission Standards and Test Procedures and 2009 t hrough 2016 Model 
Greenhouse Gas Exhaust Emission Standards and Test Procedures for 
Passenger Cars, Light -Duty Trucks, and Medium -Duty Vehicles. Amended 
December 6, 2012. 
• CARB. 2018. California 2015 and Subsequent Model Criteria Pollutant Exhaust Emission Standards and Test Procedures and 2017 and Subsequent Model Greenhouse Gas Exhaust Emission Standards and Test Procedures for Passenger Cars, Light -Duty Trucks, and Medium -Duty Vehicles. A mended 
December 19, 2018 . 
• GPA Midstream Association. 2017. GPA Midstream Standard 2140 -17, 
Liquefied Petroleum Gas Specifications and Test Methods. Adopted as 
Recommended Procedures 1931, revised  2017.  
• International Organization for Standardization  (ISO) . 2020.  ISO 8178 -1, 
Reciprocating internal combustion engines — Exhaust emission measurement 
— Part 1: Test -bed measurement systems of gaseous and particulate emissions. 
Reference number ISO 8178- 1:2020(E). Published June 2020. 
• National Institute of Standards and Technology ( NIST) . 1994. NIST Technical 
Note 1297, 1994 Edition,  Guidelines for Evaluating and Expressing the 
Uncertainty of NIST Measurement Results . September 1994.  
• NIST. 2008.  Special Publication  811, 2008 Edition, Guide for the Use of the 
International System of Units (SI) . March 2008 . 
• SAE International (SAE). 2011. Surface Vehicle Recommended Practice SAE  
J1151 , Methane Measurement Using  Gas Chromatography. S tabilized 
September 2011. 
• SAE. 2011. Surface Vehicle Standard SAE J1527, Marine Fuel Hoses. Revised 
February 2011 . 
• SAE. 2012. Surface Vehicle Standard SAE J30, Fuel and Oil Hoses. Revised 
February 2012 .  
38 • SAE. 2013. Surface Vehicle Recommended Practice  SAE J2996, Small Diameter 
Fuel Line Permeation Test Procedure. Issued January 2013 . 
• SAE. 2017. Surface Vehicle Recommended Practice SAE J1930, 
Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations, and 
Acronyms - Equivalent to ISO/TR 15031- 2. Revised March 2017. 
• SAE. 2019. Surface Vehicle Recommended Practice  SAE J1737, Test Procedure 
to Determine the Hydrocarbon Losses from Fuel Tubes, Hoses, Fittings, and Fuel Line Assemblies by Recirculation. Revised August 2019. 
• Title 40, Code of Federal Regulations, Part 63, Appendix A —Test Methods, 
Test Method 320—Measurement of Vapor Phase Organic and Inorganic Emissions by Extractive Fourier Transform Infrared (FTIR) Spectroscopy.  Last 
amended December 2, 2020. 
• Title 40, Code  of Federal Regulations, Part 86—Control of Emissions from New 
and In -Use Highway Vehicles and Engines , section 86.132- 96(j). Last amended 
June 29, 2021.  
• Title 40, Code of Federal Regulations, Part 1051—C ontrol  of Emissions from  
Recreational  Engines and Vehicles , section 1051.505. Last amended 
June 29, 2021.  
• Title 40, Code of Federal Regulations, Part 1068—G eneral  Compliance  
Provisions  for Highway , Stationary, and Nonroad  Programs , sections  1068.103(f)  
and 1068.215. Last  amended June 29, 2021.  
• Title 40, Code of Federal Regulations, Part 1090—Regulation of Fuels, Fuel Additives, and Regulated Blendstock s. Last amended December 4, 2020. 
These documents are necessary to ensure that all SORE test procedures are following the most current version of procedures and guidance on engines. 
b. Emission Reduction Credit Programs  
Under the Proposed Amendments, manufacturers may continue to use emission reduction credits  through the  averaging, banking, and trading (ABT) program s. The 
ABT program s allow manufacturers to earn  credits when they certify SORE that emit at 
levels lower than the current emission standards. These credits may be 1) used to 
offset emissions from  SORE that emit at higher levels (referred to as averaging);  2) 
banked for future years; or 3) traded with other manufacturers. Credits expire after 
five years if they have not been used. Staff  expect s that, overall, generator engines 
would  use more credits than they ear n after MY 2023. The sales- and power -weighted 
average HC + NO
x emission rates for MY 2018 generators exceed the proposed MY 
2024 emission standards. N o credits could  be earned once emission standards of zero 
are implemented  for generator engines . Therefore, only remain ing banked credits  
could be used for MY  2028 and subsequent model year  engines . This would  result in  a 
replacement of SORE equipment with ZEE as it reaches the end of its  useful life over 
time. The transition to ZEE  would  reduce NO x and ROG  emissions and improve 
California’s air quality , consistent with the 2016 State SIP Strategy .  
39 The Proposed Amendments would lower the  maximum family emission levels (FEL) for 
engines. An FEL is defined as an emission level that is declared by the m anufacturer to 
serve for the ABT program and in lieu of an emission standard for certification . 
Establishing more stringent  maximum FELs is necessary to accelerate exhaust emission 
reductions in order to achieve the necessary SORE emission reductions by 20 31 as 
expected under the 2016 State SIP Strategy . The lower maximum FELs would be 
equivalent  to the current HC + NO x exhaust emission standards, shown in Table II-1. 
These lowered maximum FELs for HC + NO x would ensure that no MY 2024 or 
subsequent model year engines are introduced for sale or lease for use or operation  in 
California with excessive exhaust emissions, while still allowing manufacturers flexibility 
to use the credits they have generated to sell engines with emissions above the 
proposed, more stringent emission standards.  This would  ensure the highest -emitting 
engines, which have the greatest impact on air quality and expose operators to the greatest amounts of pollutants, are replaced with  ZEE the earliest.  
These lower maximum FELs would also maintain maximum flexibility for manufacturers 
to shift their focus to ZEE. By setting the maximum FELs to the current  emission 
standards, manufacturers could  continue using credits they have banked or ear n in 
future years on engines already in production today, without having to develop new 
technology.  
The Proposed Amendments would also allow alternative fuel –powered  SORE  
equipment to qualify for evaporative emission credits. This includes engines powered 
with CNG , propane, LPG , or LNG . These engines are not subject to the evaporative 
regulations, but if manufacturers wish to earn emissions credits, they may follow the test procedure to do so. This will allow more flexibility in production and give credits to manufacturers of low -emitting  engines.  
Currently, the emission reduction credit program for evaporative emissions only has 
provisions for averaging and banking. The Proposed Amendments would add trading 
to the program to align with the exhaust emission regulations. This would  allow more 
flexibility in the program . Manufacturers who earn  credits could  trade them to other 
manufacturers, encouraging production of  the lowest -emitting  engines possible.  
To send another market signal to manufacturers to increas e development and 
production of zero- emission generators, the Proposed Amendments also include a 
new, generator -specific emission reduction credit program. This voluntary program 
would allow manufacturers to offset emissions from  generators with emission l evels 
above the proposed emission standards  by using credits earned  from certifying  
zero- emission generators. All SORE, including generator engines, may be included in 
engine families participating in the  certification  averaging, banking and trading 
progra m described in § 2408. Zero -emission generators, however, are not among the 
equipment types included in the ZEE  credits averaging, banking and trading program 
described in § 2408 .1. The program in § 2408.1  prioritized lawn and garden 
equipment because professional landscapers use such equipment extensively. T he 
emission inventory calculated with SORE2020 indicates that generators produce the 
highest statewide emissions of any small off -road equipment type. In 2020, g enerators  
40 accounted  for approximately 14 percent of the total population of SORE equipment, 
and 19 percent of all NO x and ROG  emissions from SORE (CARB, 2020).  The function 
of generators is to provide electrical power rather than perform mechanical work (as 
lawn and garden equipment does), so zero- emission generators often do not contain 
an electric motor. Instead, zero -emission generators often convert chemical energy to 
electrical energy without the use of an electric motor.  This makes incorporation of 
zero- emission generators into the same Z EE credits averaging, banking, and trading 
provisions as lawn and garden equipment less straightforward.  
The Proposed Amendments add a new and separate program for zero -emission 
generators for simplicity. The program is tiered, granting more emission reduc tion 
credits for zero -emission generators with greater energy storage and power delivery  
than for those with less energy storage and power delivery. This tier system  would  
enable the greatest credit benefits to manufacturers who develop zero -emission 
gener ators in the least developed sector of the market  (i.e., zero -emission generators 
with the greatest energy storage and highest power output). The z ero-emission 
generator  credits would  be subject to similar provisions to those in the existing 
emission reduc tion credit programs, including a five -year limit on banking credits.  
In summary, the Proposed Amendments would expand the current emission reduction 
credit programs to increase flexibility for manufacturers . These amendments are 
intended to lessen the ini tial cost impacts for manufacturers (and those purchasing 
equipment) that could result when SORE equipment is replaced with ZEE. The credit 
programs spread out the cost impact over a longer time. Throughout the economic 
analysis described in Chapter VII and Appendix I of this Staff Report, credit use has 
been modeled such that all banked credits are used  before the y expire .  
The Proposed Amendments include revisions to the emission reduction credit 
programs in following SORE regulation s: CCR §§ 2408, 2408.1, 2408.2 , 2754.1,  and 
2754.3.  
B. Exhau st Emissions Durability Periods f or SORE  Do Not Represent Actual 
Lifetimes 
1. The Problem  
The exhaust emissions durability period is the period that represents the engine’s 
useful life. Under California Part  1054. 107, useful life is described as the period  during 
which engine s are required to comply with all  applicable  emission standard s. The 
current regulations allow applicants for certification to select a durability period for their engines from a range of choices that generally reflect “moderate,” “intermediate,” or “extended” use.  Actual use times, as found in the CSUF survey  
(CSUF SSRC, 2019), are often much longer  than the emissions durability periods 
defined in the current regulations.  The 75
th percenti le age of in -use residential 
generators is 15 years  (CSUF SSRC, 2019) . SORE2020 includes an average residential 
activity rate for  a generator of 62 hours per year  (CARB, 2020) . A generator used at 
the average residential activity level  would  be used for 93 0 hours in 15 years. 
SORE2020 includes an  average professional activity rate for a generator of 146 hours  
41 per year (CARB, 2020) . The 75th percentile  age of a generator owned by a 
nonlandscaping business is 1 5 years  (CSUF SSRC, 2019) . A generator used at the 
average professional activity level  would be used for 2,190 hours in 15 years. 
In addition to actual use time, many manufacturers advertise use of their products for 
longer than the durability period. Honda’s GX120, GX160, and GX200 engines are 
each  certified to a n emissions durability period of 500 hours. However, the 
maintenance schedule in the owner’s manual  indicates  the cyclone -type air filter 
should  be changed for the first time after 600 hours of engine operation (Honda, 
2020 c. Westerbeke’s 9.9E,  J3 and J4 generators are each certified to an emissions 
durability period of 250  hours, but their website says, “ It is not uncommon to hear that 
generator sets and engines have run up to 10,000 hours with no major repairs.” (Westerbeke, 2016 ). This discrepancy means some SORE  may be emitting at levels 
above the emission standards for a large portion of their use time.  
SORE equipment besides generators would also be subject to longer durability 
periods when using credits to certify.  Currently, lawn mowers may certify at durability 
periods ranging from 125 to 500 hours. However, the 75
th percentile age for a 
residential  lawn mower is 15 years  (CSUF SSRC, 2019) . Average residential use time 
for lawn mowers is 19 hours per year  (CARB, 2020). A residential lawnmower used at 
the average rate  would  be used 285 hours in 15 years. L andscapers , on average,  use 
lawn mowers for 240 hours per year  (CARB, 2020) , and the 75th percentile age is 3 
years  (CSUF SSRC, 2019) . A lawn mower owned by a landscaper used at the average 
rate would  be used for 720 hours in 3 years . 
The SORE2020 emissions inventory model  used to quantify emission reductions due to 
the Proposed Amendments assumes emissions deteriorate  (i.e., increase)  to a level 
equal to the proposed  emission standard s at the end of the emissions durability 
period and then remain at that emission level until the equipment is no longer used . 
Section III.A.3 includes additional discussion of the use of SORE2020  to quantify 
emission reductions due to the P roposed Amendments.  
The actual use times of equipment today are significantly longer than many of the 
durability periods specified in the SORE regulations, which can result in excess 
emissions.  If engines are kept by users for longer than the durability period, California 
may not re alize the emission reductions estimated under the Proposed Amendments . 
Therefore, based on this better understanding of a generator’s actual operating hours 
during it s useful life, c urrent regulations need to be updated to more accurately reflect 
the current lifetime use period of generators.  
2. The Solution  
The Proposed Amendments would change the emissions  durability periods to more 
accurately reflect the actual  lifetime of  SORE equipment . This would  prevent  
manufacturers from certifying to unrealistically short emissions durability periods and 
only meeting the emission standards for a small portion of the equipment’s lifetime . 
Table II- 3 and II -4 describe the curren t and proposed exhaust emissions durability  
42 periods for SORE.  The proposed durability period for all SORE  with displacement less 
than or equal to 80 cc other than generator  engines is 300 hours.  The proposed 
durability period for generator engines  with dis placement  less than or equal to 80 cc is 
500 hours.  The proposed durability period for engine s with displacement greater than 
80 cc and less than 225 cc is 500  hours. The proposed durability period for engine s 
with displacement greater than or equal to 225  cc is 1,000 hours. The durability 
periods in the Proposed Amendments are the longest of the current durability periods 
for each displacement category for engines  other than generator engines with 
displacement less than or equal to 80 cc . Generators are not handheld equipment and 
do not have the same limitations of space and weight as handheld equipment. Among 
generators that use engines with displacement less than or equal to 80 cc, most have 
80 cc engines. The design of many 80 cc engines is closer to that of an engine with displacement greater than 80 cc than it is to that of engines used in handheld equipment. The example in this section illustrates that a residential generator with an 
engine with displacement less than or equal to 80 cc used at the average residential 
activity level may be used well in excess of its current 50- to 300 -hour durability 
period. A 500- hour durability period assures more residential generators using engines 
with displacement less than 225 cc will meet the emission standard for their lifetime.  
For all displacement categories except greater than 825 cc, t here are currently 
engines certified below the proposed emission standards at the longest current durability periods. The proposed emission standard s and emissions durability period 
for engines with displacement greater than 825 cc are aligned with the current 
emission standard and emissions durability period for similar LSI engines, i.e., those 
rated greater than 19 kW and with displacement greater than 825 cc.  Therefore, these 
durability periods are technologically feasible  for SORE . 
The Proposed Amendments include revisions to the durability periods as listed in 
CCR § 2403.   
43 Table II -3. Current  SORE emissions durability periods and emissions durability 
periods for generator  engine s under the Proposed Amendments . 
Displacement category  Current emissions 
durability periodj  
(hours)  Proposed emissions 
durability period for MYs 2024 and later  
(hours)  
< 50 cc  50/125/300  500 
50-80 cc , inclusive  50/125/300  500 
> 80 cc - < 225 cc  125/250/ 500 500 
225-825 cc, inclusive  125/250/500/1,000  1,000  
> 825 cc  125/250/500/1,000  1,000  
Table II -4. Current  SORE emissions durability periods and emissions durability 
periods for SORE other than generator  engines under the P roposed  
Amendments.  
Displacement category  Current emissions durability period
j  
(hours)  Proposed emissions durability period for 
MYs 2024 and later  
(hours)  
< 50 cc  50/125/300  300 
50-80 cc, inclusive  50/125/300  300 
> 80 cc - < 225 cc  125/250/ 500 500 
225-825 cc, inclusive  125/250/500/1,000  1,000  
> 825 cc  125/250/500/1,000  1,000  
C. Trading of Evaporative Emission Credits Is Not Permitted , Restricting  
Manufacturer Flexibility  
1. The Problem  
Under the current regulations, manufacturers may not trade evaporative emission 
credits. A manufacturer may only average and bank  credits  for its own future use. This 
limits manufacturer flexibility . This lack of flexibility could be particularly challenging 
for manufacturers  under the Proposed Amendments when emission standards would  
be zero and credit use would be  the only compliance path for SORE equipment with 
                                            
j Manufacturers choo se the emissions durability period which matches the expected useful life of an 
engine family. These categories are generally taken to reflect “ moderate,” “intermediate,” and 
“extended”  use.  
44 nonzero emissions . This may result in unbalanced portfolios between exhaust and 
evaporative credits  for manufacturers  because credit trading is allowed under the 
SORE exhaust emission regulations.  Manufacturers who possess banked exhaust 
emission reduction credits and no evaporative emission reduction credits could be 
unable to offset the evaporative emissions of their engines without the ab ility to trade 
evaporative emission credits with other manufacturers.  It is necessary to amend the 
evaporative emission credit provisions to increase flexibility for manufacturers to facilitate compliance with the proposed emission standards and increase cost -
effectivene ss of the Proposed Amendments.  
2. The Solution  
Trading provisions have been added to the evaporative emission regulations under 
the Proposed Amendments. These provisions would  allow manufacturers to trade 
evaporative emission credits with one another, if d esired.  The proposed evaporative 
emission credit trading provisions are similar to the existing trading provisions in the 
exhaust emission credit regulations. Manufacturers  could  use credits  to offset 
emissions from their own evaporative  familie s or they could trade earned credits to 
other manufacturers to generate revenue. An increase in certification of ZEE would 
increase its availability to users in California, further developing the market and 
accelerating the adoption of  ZEE in place of SORE equipment . 
The Proposed Amendments include revisions to credit provisions to incorporate  
trading in the following sections of the SORE regulations: CCR §§ 2754.1, 2754.3  
D. Fuel Caps and  Tethers Can Cause Fuel to Spill  
1. The Problem  
The evaporative emission regulations require fuel caps for fuel tanks used on engines 
with displacement greater than 80 cc  to be secured to the fuel tank, equipment or 
engine with a tether. This prevents fuel caps from falling and becoming damaged or 
dirty. It also prevents them from bei ng lost. Some fuel  caps are equipped with internal 
tethers , i.e., with tethers that are attached to a location inside the fuel tanks. Other 
fuel caps incorporate fuel gauges that extend into the fuel in the fuel tank or otherwise 
come into contact with liq uid fuel inside the fuel tank.  During evaporative emissions 
compliance testing and other observations of engines, CARB staff has observed fuel 
spilling or dripping from several pieces of equipment when the fuel cap s were  
removed. Based on these observations, CARB staff  concludes that there is greater 
likelihood that t hese tethers and fuel caps may  cause users of SORE equipment to spill 
or drip fuel when removing a cap from the fuel  tank, thereby creating excess emissions 
neither captured in current test procedures nor reflected in CARB’s emissions 
inventory. Therefore, it is necessary to amend the test procedures to ensure that fuel 
caps and tether s are designed to prevent fuel spillage. It is also necessary for 
certification applicants to include information  in their applications to show that the ir 
engines meet relevant emission standards.   
45 2. The Solution  
The Proposed Amendments add a provision to the SORE  regulation s to require that 
fuel caps and their tethers must not cause fuel to spill when fuel caps are removed . 
This will reduce emissions when fuel caps are removed to check the fill level and 
during refueling. This provision  is not expected to impact equipment costs, overall. 
Some manufacturers may move the tether ho lding the fuel cap from inside the gas 
tank to the outside. For some engines, this may reduce the cost of the tether, as the 
material has less exposure to gasoline. F or other engines, it may increase the costs, as 
they may have to weld a tab onto the fuel tank to attach the tether. Any cost or 
cost-savings is expected to be negligible.  
The Proposed Amendments include revisions to the fuel cap and tether  requirements 
and test procedures included in the following section of the SORE regulations and 
documents incorporated by reference:  
CCR § 2756  
Small Off -Road Engine Evaporative Emissions Test Procedure, TP -901, Test Procedure 
for Determining Permeation Emissions from Small Off -Road Engine Fuel Tanks  
Small Off -Road Engine Evaporative Emissions Test Procedure, TP -902, Test Procedure 
for Determining Evaporative Emissions from Small Off -Road Engines 
E. The Variance Provisions Cause Inequitable Results, Leading to Potential 
Unmitigated Excess Emissions  
1. The Problem  
Under the current evaporative emission regulatio ns, a manufacturer that cannot meet 
the requirements set forth in §§ 2754 through 2757, due to extraordinary reasons 
beyond the manufacturer’s reasonable control, may apply in writing for a variance.  The 
provision requires that a manufacture r mitigate the noncompliance  to the maximum 
extent feasible. Two manufacturers have been granted variances . Excess emission s 
mitigation  can be accomplished  by certain methods including, but not limited to , 
relinquishing  the relevant amount of evaporative emission credits or by setting a 
higher evaporative model emission limit  to offset the excess emissions under the 
variance. While the variance procedure may provide a relief valve for some 
manufacturers that could not  meet certain requirements due to extraordinary reasons 
beyond the manufacturers’ reasonable control , it provides no relief for those 
manufacturers who may have had some reasonable control over their ability to meet certain requirements but still could not me et those requirements. In essence, the 
variance procedures create inequitable results, rewarding some manufacturers who qualify for the process while leaving others who may need relief but do not meet the 
threshold criteria. In turn, manufacturers that do not qualify for the variance process 
may choose to try to certify their engines even though they may not meet all the requirements for certification, which could result in unmitigated excess emissions. When the emission standards are zero, no further credits may be earned.  Under the  
46 variances currently in force, estimated  statewide excess emissions have been offset by 
relinquishing evaporative emission  credits or by setting a higher evaporative model 
emission limit . If there were  insufficient credits, excess emissions may not be 
completely offset. This could  result in higher than expected emissions and the 
reductions expected under the Proposed Amendments would  not be met.  
2. The Solution  
The variance provision of the evaporative regulations is repealed under the Proposed 
Amendments. This would  no longer allow a manufacturer that cannot meet the 
requirements set forth in §§ 2754 through 2757, due to extraordinary reasons beyond the manufacturer’s reasonable control, to  apply in writing for a variance . This wo uld 
ensure equity for all manufacturers, because all manufacturers would be required to meet the requirements of the regulations. The addition of evaporative emission credit trading would also alleviate the need for variances , which would enable all 
manufa cturers to certify their engines in a manner consistent with the SORE 
evaporative emission standards; manufacturers  who could not meet the emission 
standards could acquire credits to offset emissions above the emission standards.  
The Proposed Amendments include repealing the variance provision in the following 
section of the SORE regulations: CCR § 2768 . 
F. Tilting Equipment for Cleaning and Maintenance C an Result in Excess Emissions  
1. The Problem  
Currently, as discussed in section II.A.1, a large portion of SORE that has been 
compliance tested for evaporative emissions has failed. Updates to the evaporative 
emission test procedures are needed to increase compliance rates.  CARB staff ha s 
observed two significant opportunities for excess evaporative emissions resulting from 
normal equipment maintenance, neither of which is quantified using existing test procedures.   
Fuel can spill when equipment is tilted for cleaning, maintenance,  transport or storag e. 
Figure II-4 shows a hydraulic jack which can be used to tilt a riding mower for cleaning 
and maintenance. Other equipment, such as walk -behind mowers and pressure 
washers , are easily tilted by the user.  Mi-T-M, a manufacturer of pressure washers and 
other small off -road equipment, provides instructions to enable a user to start an 
engine after it has been tipped (Mi -T-M, 2021). Those  instructi ons discuss the 
possibility of  engine oil getting into the cylinder, preventing the engine from starting, 
or cont aminating the air filter. The presence of oil on the air filter could affect the 
amount of air going into the engine, potentially resulting in excess emissions.  It is also 
possible when equipment is tilted that liquid fuel can contact the carbon canister, 
which must be prevented.  The carbon canister captures evaporative emissions from 
the fuel tank when the equipment is stored. Once liquid fuel has contacted the carbon 
canister, it can be spoiled and no longer work as intended. This can  result in excess 
evaporative emissions during equipment storage, and therefore, expected emission 
reductions will not be realized. CARB staff has noted that tilting equipment , including  
47 equipment that has two wheels and must be tilted for transport,  may contribute to its 
failure to meet emission standards in testing  (CARB, 2016b) . 
Figure II -4. A hydraulic jack  being used to clean under a riding lawn mower.  
 
(Photo from Costco, 2021)  
2. The Solution  
Under the Proposed Amendments, TP -902 would include a tilt test before evapora tive 
emission testing. The tilt test consists of tipping a piece of equipment 90 degrees in 
three directions, without tilting toward the carburetor, and will account for any emissions that come from fuel leaks when equipment is turned on its side for cleaning , 
maintenance, transportation  or storage. The tilt test is not expected to have a 
significant impact on costs to manufacturers as it adds only a few minutes of staff time 
to a multi -month testing period. Also, the current regulations include requirement s 
that are expected to ensure evaporative emission control systems would not be 
negatively affected by momentary tilting of the engine.  An example is the requirement 
in § 2754 of the evaporative emission regulations to install carbon canisters in a way 
that prevents exposing the carbon to water or liquid fuel.  
The Proposed Amendments include revisions to incorporate the tilt test in  the 
following test procedure incorporated by reference:  
CARB. Small Off -Road Engine Evaporative Emissions Test Procedure, TP -902, 
Test Procedure for Determining Evaporative Emissions from Small Off -Road 
Engines  
 
48 G. Manufacturers May Not Determine Fuel Tank Pressure Limits Accurately  
1. The Problem  
The evaporative emission test procedures, TP -901 and TP -902, include pressure tests 
for fuel tanks. The test procedures also require manufacturers to d etermine a fuel tank 
system’s design pressure and vacuum limits under normal operating and storage 
conditions , considering the influence of any associated pressure/vacuum relief 
components . Currently, there is no specified procedure  for determining these fuel 
tank pressure limits. The test procedures do not require a pressure test i f the fuel 
tanks have no features that would cause positive or negative pressure to accumulate during normal operation or storage . The method  for determining the  pressure limits is 
left to the manufacturer.   
If tanks actually operate or are stored at pressures outside the window of the pressure 
test conducted, fuel tanks may weaken under real -world  use. The weakening can result 
in excess evaporative emissions from the fuel tanks due to thinning or cracks that can 
occur.  
2. The Solution  
A procedure for determining pressure limits of tanks has been added to the 
evaporative test procedures  as part of the Proposed Amend ments . This test ensures 
that manufacturers determine pressure limits of their tanks uniformly. It further ensures 
that pressure tests are cycled through the actual high er and lower pressures that tanks 
may achieve when operating or stored  during actual us e by a consumer . 
Encompassing the full range of pressures experienced by the fuel tank is vital for the 
integrity of the evaporative emission test. If the tank is cycled through a smaller 
pressure range than actually experienced by the tank under normal op erating 
conditions , or no pressure test is performed, it may not properly stress the tank and 
reveal weaknesses that contribute to excess emissions.  
The Proposed Amendments include revisions to  specify the pressure testing in the 
following test procedures incorporated by reference:  
CARB. Small Off -Road Engine Evaporative Emissions Test Procedure, TP -901, Test 
Procedure for Determining Permeation Emissions from Small Off -Road Engine Fuel 
Tanks  
CARB. Small Off -Road Engine Evaporative Emissions Test Procedure, TP -902, Test 
Procedure for Determining Evaporative Emissions from Small Off -Road Engines  
H. Manufacturers Wish to Accelerate  Preconditioning  
1. The Problem  
Manufacturers frequently request a pproval for accelerated preconditioning of fuel 
tanks or evaporative emission control systems  when planning to conduct  evaporative 
emission testing. Preconditioning is the process of exposing evaporative emission 
control systems or their components to liquid fuel or fuel vapors to a point of  
49 maximum permeation to ensure the evaporative emissions measured in a test 
represent the emissions that would occur in real -world use. For example, evaporative 
emissions from a new engine that has not previously contained fuel would be expected to be lower if they were measured the first day fuel were introduced to the fuel tank than after the fuel tank had contained fuel for a longer period of time.  Under 
the current test procedure, manufacturers are required to precondi tion evaporative 
emission control systems or components  for 140 days or provide data documenting 
that emissions will not increase with further preconditioning for units preconditioned 
less than 140 days. The data that must be provided are not specified in the test 
procedures.  Manufacturers frequently request a reduction in that time. If 
manufacturers wish to shorten the preconditioning time, it is vital that all evaporative emission control system  components have already reached maximum permeation to 
ensure that the evaporative emission testing represents real -world emissions. If the 
fuel contact time is insufficient, the test may not capture actual evaporative emissions 
from the equipment  representative of real -world operations.  
2. The Solution  
The evaporative test procedures have been modified to add specifications for data 
documenting that evaporative emissions will not increase with further preconditioning 
to clarify requirements for accelerated preconditioning. The specifications would 
ensure that all manufacturers know the requirements for accelerated preconditioning and that they are applied consistently to all manufacturers to maintain a level playing field. 
The Proposed Amendments include revisions to the preconditioning requirements in 
the following test procedures incorporated by reference:  
CARB. Small Off -Road Engine Evaporative Emissions Test Procedure, TP -901, Test 
Procedure for Determining Permeation Emissions from Small Off -Road Engine Fuel 
Tanks . 
CARB. Small Off -Road Engine Evaporative Emissions Test Procedure, TP -902, Test 
Procedure for Determining Evaporative Emissions from Small Off -Road Engines. 
I. CARB Test Procedures Have Become Inconsistent with U.S. EPA Test 
Procedures  
1. The Problem  
U.S. EPA test procedures for exhaust emissions have been updated since CARB test 
procedures were last updated. Those updates have created inconsistencies between U.S. EPA and CARB test procedures that are unnecessary and add to regulatory 
complexity for manufacturers.  Under the CARB test procedure s, measurement 
instrumentation is more limited than allowed by U.S. EPA.  The U.S. EPA procedures 
specif y engine preconditioning requirements for various types of engines, while no 
such specificity exists under CARB procedures.  U.S. EPA procedures include new 
procedures for determining the mass of nonmethane hydrocarbons from the 
measurement of total HC, which is absent in the CARB procedures.  
50 2. The Solution  
The CARB exhaust test procedures have been updated to harmonize with U.S. EPA 
test procedures through out. Changes to U.S. EPA test procedures have not been 
incorporated if they are less stringent tha n the CARB’s requirements. This 
harmonization simplifies testing for manufacturers and allows for easier comparison of 
the test procedures.  With the test procedures more closely aligned, manufacturers 
may do less testing overall and have less  confusion between the U.S. EPA and CARB 
test procedures. Some of these changes include allowing more types of 
instrumentation for measurement of HC emissions. 
The Proposed  Amendments include revisions to the following test procedures 
incorporated by reference:  
CARB. California Exhaust Emission Standards and Test Procedures for New 2013 and 
Later Small Off -Road Engines; Engine- Testing Procedures (Part 1054) . 
CARB. Proposed A mendments to California Exhaust Emission Standards and Test 
Procedures for New 2013 and Later Small Off -Road Engines ; Engine -Testing 
Procedures (Part 1065) . 
J. Compliance Testing of Exhaust Emissions from Engines is Overly Burdensome  
1. The Problem  
Under the current regulations, CARB is required to test up to 30 engines to determine compliance of an engine family with exhaust emission regulations. This is overly 
burdensome and makes it extremely difficult for CARB to conduct compliance testing. Without compliance testing, CARB cannot verify that engines are actually meeting the emission standards set forth in the regulations. If engines are no t complying with the 
emission standards, excess emissions will occur.  
2. The Solution  
Under the Proposed Amendments, the current exhaust emission compliance testing requirement to test “a reasonable number” of engines has been changed to “one or more.” This will allow CARB to perform compliance testing of exhaust emissions 
without the onerous burden of testing up to 30 engines from an engine family before making a determination whether the family meets the emission standards. Th e 
requirement that engines be tested in “groups of five” has been deleted . This will 
allow for broader exhaust emission compliance testing of SORE.  
The Proposed Amendments include revisions to the compliance testing procedures 
included in the following sections of the SORE regulations and documents 
incorporated by reference:  
• CCR § 2407 . 
• CARB. California Exhaust Emission Standards and Test Procedures for New 
2013 and Later Small Off -Road Engines; Engine- Testing Procedures (Part 1054) .  
51 • CARB. Proposed Amendments to California Exhaust Emission Standards and 
Test Procedures for New 2013 and Later Small Off -Road Engines ; Engine-
Testing Procedures (Part  1065) . 
K. Other Changes to the Regulations and Procedures  
Other administrative changes have been made to the regulations and certification and 
test procedures  to provide clarity for manufacturers . These are detailed in Chapter XI 
of this document . 
III. Air Quality  
The SORE regulation s have been successful at reducing emissions over the last 
25 years. The P roposed Amendments would continue to improve the SORE 
regulations to achieve  additional emission reductions and accelerate the adoption of 
ZEE to help California attain and maintain ambient air quality standards. The Proposed 
Amendments are designed to max imize emission reductions a nd achieve the  expected 
emission reductions in the 2016 State  SIP Strategy specified for SORE and would 
reduce  emissions of  pollutants that have  multiple known adverse health effects. 
Emissions of  NO x and ROG  from SORE contribute to  formation of  three criteria air 
pollutants —ozone, PM and NO 2—either directly (NO 2 and PM) or indirectly ( NO 2, 
ozone , and PM). As described in Chapters I and IV , all of these criteria air pollutants 
have adverse health effects. The Proposed Amendments would also reduce GHG 
emissions and petroleum use.  The Proposed Amendments are part of a portfolio of 
“Strategies, in coordination with other State agencies, U.S. E nvironmental Protection 
Agency  and local air districts, to achieve 100 percent zero -emission from off -road 
vehicles and equipment operations in the State by 2035,” which  EO N-79-20 
(California Executive Order No. N -79-20, 2020)  orders CARB to develop and propose . 
As described in Chapters II and XI , the Proposed Amendments  would increase the 
adoption of ZEE for small off -road equipment  regulated by the State at the earliest 
practicable date . This chapter describes the methodology by which the emission 
benefits were estimated and a summary of results as they relate to the 2016 State SIP 
Strategy.  
A. SORE  Emission Inventory and Modeling Methodology  
To quantify emission reductions due to the Proposed Amendments, staff developed 
an updated version of the SORE emissions inventory  model , SORE2020. This updated 
version of the model uses the data collected as part of the CSUF survey as well as 
various emissions testing and reporting  data to calculate SORE emissions. This section 
describes in detail the small off -road equipment  emission inventory as well as the 
SORE2020 model.  
1. SORE2020 Model Description  
The updated, stand -alone SORE2020 model reflects the California economy 
recovering from the 2008 economic recession and incorporates emission results from  
52 CARB’s recent in- house testing as well as CARB’s most recent certification data and  
the CSUF survey  (CSUF SSRC, 2019) . Data collected through this survey provide the 
most up -to-date information regarding the population and activity of small off -road 
equipment in California. SORE2020 incorporates the latest information for the base 
year p opulation, population growth, equipment usage, spatial allocation, and emission 
factors, along with an intuitive, graphical user interface.  
Staff presented the draft version of the SORE2020 model along with details on its 
methodologies and data inputs at a  public workshop in April 2020 and released the 
final version of the model in September 2020. The final version of the model incorporate s comments from industry and stakeholders received since the April 2020 
workshop.  
Compared to the previous emissions inventory model, OFFROAD2007, which only 
contained equipment used in the residential and business sectors, the SORE2020 Model also includes a third sector, landscapers.  The population of equipment in the 
landscaping business  sector is relatively low  compared to the population  of equipment 
owned by residents. H owever , the activity is significantly higher than it is for  
equipment  designated for residential use.  
The SORE2020 model is designed to be user -friendly and allows flexibility in selecting 
categories with specified inputs, such as population, activity, or emission factors, to accommodate custom outputs or to run different scenarios.  Compared to the previous 
model, ROG emission estimates from SORE2020 are higher than those from 
OFFROAD2007, and range from 23  percent higher in calendar year 2020, to 4 percent 
higher in 2050. Similarly, NO
x emission estimates from SORE2020 are also higher than 
OFFROAD2007,  and range from 15 percent higher in calendar year 2020,  to 
10 percent higher in 2050.  
The total equipment population in the light c ommercial equipment category was 
updated in SORE2020 , which resulted in a three- fold increase in emissions even 
though annual equipment usage in the final SORE2020 m odel for light commercial 
equipment is lower than in OFFROAD2007.  The increase in the population of the light 
commercial equipment category was one of the main drivers of increased  total 
emissions in SORE2020 compared to OFFROAD2007.  
Emissions estimates for each type of SORE equipment in tons per day were calculated through 2050 by multiplying the emission factor by activity data and total population 
of the equipment. SORE2020 can output daily emissions estimates for total 
hydrocarbons (THC), total organic gases,  ROG, CO , carbon dioxide (CO
2), NO x, PM, 
particulate matter with diameter of 10 micro meters or less  (PM 10), PM 2.5, and oxides of 
sulfur . The model was refined through  outreach and workshops with the general public 
and industry stakeholders. Further details on the model methodology can be found in 
the SORE2020 Technical Report (CARB, 2020).   
53 Finally, SORE2020 includes ZEE  to estimate the impact of the increasing trend toward 
electrification in the lawn and  garden equipment and light commercial equipment 
categories.  ZEE were not included in prior SORE  emission inventories.  
2. Baseline Small Off -Road Equipment Inventory  
Conditions under the current SORE regulations are referred to as the “ Baseline  
Scenario ” in this emissions analysis. The Baseline Scenario assumes that no further 
regulations would be adopted over the regulatory horizon of 2023 t hrough 2043.  The 
equipment population inventory used in the Baseline Scenario  was developed with the 
data obtained from the CSU F survey (CSUF SSRC, 2019) , engine production lin e 
testing sales data from  SORE manufacturers’  reports  provided to CARB, and 
evaporative emissions production volume  reporting data , also submitted to CARB 
from SORE manufacturers . 
The SORE  population inventory separates the total amount of small off -road 
equipment in the state into several categories. First, the equipment  are separated by 
type of owner. There are three  categories:  residents, businesses, and landscapers. 
Residents are individuals in the state that own residential -grade small off -road 
equipment for their private use. Businesses are defined as those that own small off -
road equipment to maintain their own property or conduct work, excluding 
landscap ers. Finally, landscapers include all businesses under North American Industry 
Classification System codes 541320 (Landscape and Architectural Services) and 
561730 (Landscaping Services). The share of small off -road equipment belonging to 
residents, businesses, and landscapers is based on the CSUF survey.  The population is 
also categorized by power type, whether SORE equipment or ZEE.  Finally, the 
population is categorized by equipment type.   
From the base  year population, staf f modeled the statewide small off -road equipment  
population into future years. Growth is expected in both  ZEE and SORE equipment 
population s. The modeling utilized household growth projections in California  along 
with historical shipment data for gasoline -powered  equipment . The small off -road 
equipment population in the past has tracked well with household growth, so that was used as a proxy for future years  (CARB , 2020) . Staff developed a survival curve for 
each category of equipment to calculate the population of a given MY over time. This curve is based on the age distribution of equipment  from CSUF survey data. 
Figure III- 1 shows the modeled total population of small of f-road equipment starting in 
the economic base year of 2022 and during the regula tory horizon  of 2023 through  
2043. In 2035, under the Baseline Scenario, only 54 percent of all small off -road 
equipment subject to the SORE regulations would  be ZEE.  
Median age for each equipment type was determined from the results of the CSUF 
survey. T able III- 1 shows the median age  for each equipment type by owner.   
54 Table III-1. Median equipment age from the CSUF survey . 
Type of 
Equipment Resident -Owned 
Median Age  
(Years)  Business- Owned 
Median Age 
(Years)  Landscaper -Owned 
Median Age  
(Years)  
Chainsaw  5 3 2 
Lawn Mower  6 5 3 
Leaf Blower  5 3 2 
Riding Mower  8 - 5 
Trimmer/Edger/ 
Brush C utter  5 3 2 
Generator  7 5 4 
Pressure Washer  5 3 3 
Pump  6 8 3 
Figure III -1. Modeled small off -road equipment population statewide under  the 
Baseline Scenario . 
 
The population inventory does not reflect recent economic changes associated with 
the Corona virus Disease 2019 ( COVID -19) pandemic  (Bohn et al ., 2020) . Indeed, the 
Outdoor Power Equipment Institute (OPEI)  reported record growth in sales across the 
industry in 2020 despite the economic conditions (OPEI, 2020) . Generator sales in 
response to potential PSPS in California have not yet been fully reflected in the small 
 
55 off-road equipment  inventory, where we wou ld expect an increase in generator 
emissions due to increased generator purchases and use during PSPS.  
3. SORE2020 Emissions Model Applied to Regulatory Scenario  
Estimated emissions under the Proposed Amendments are compared to emissions 
under the current  SORE regulations each year for the regulatory horizon  of 2023  
through  2043 to calculate the annual emission reduction benefit under the Proposed 
Amendments. The 2023 through 2043 regulatory horizon  was selected due to the 
length of time it will take to ha ve over 99 percent of the small off -road equipment  
population be ZEE based on emissions modeling.  
The SORE2020 model run for the Proposed Amendments also included the expected 
effect of current ABT credit banks . The most recent complete credit bank data set 
available at the time of calculation was from the end of MY  2018. As of the end of MY  
2018, manufacturers collectively held 2.0 billion  grams of exhaust emission credits and 
138 thousand  grams of evaporative emission cre dits.k Based on CARB’s historical 
records of the SORE credit bank s, the emission credit bank s for both evaporative and 
exhaust emissions have remained relatively constant over the last several years. It is 
assumed that this credit bank would remain relatively stable until the first of the new 
emission standards included in the Proposed Amendments would go into effect in 
MY 2024.  
Staff assumed that all available credits would be used by manufacturers for 
generators, and that the credits would be used equally throughout  the four -year 
period when generators would be subject to  more stringent emission standard s 
(MYs 2024 through 2027). The exhaust and evaporative credit banks were treated 
separately and assumed to be completely exhausted by the end of  MY 2027. Staff 
expect s that, overall, generator engines would use more credits than they earn after 
MY 2023. The sales- and power -weighted average HC + NO x emission rates for MY 
2018 generators exceed the proposed MY 2024 emission standards. No credits ca n be 
earned once emission standards of zero become effective for a model year. Therefore, 
only remaining banked credits could be used for  MY 2028 and subsequent model 
years . Current emission levels were calculated from sales- weighted averages of 
certification data and validation studies  conducted by CARB and industry (CARB, 
2016c and 2021)l. Staff calculated that, using a sales- weighted average, manufacturers 
could use credits to certify MY s 2024 through 2027 generators with emission rates 
higher than the newly -implemented emission standards, as shown in Tables III-2 
and III-3. These emission levels were used when calculating overall emissions 
                                            
k The credit banks are based on manufacturer reported sales data, which are confidential business 
information . They are subject to validation by CARB staff.  
l CARB’s sales- weighted averages and validation studies also relied on manufacturers’ confidential 
reported sales data for their CARB -certified engines. CARB staff aggregated the sales data across all 
SORE manufacturers to generate the sales -weighted averages. An unredacted, confidential version and 
a redacted version of the CBI will be included in the rulemaking file.   
56 reductions with SORE2020.  Scenarios where manufacturers use their banked credits 
on different types of equipment would not lead to significant differences in overall 
emissions , as shown in the sensitivity analysis in section  IV.A.1 . 
Table III -2. Exhaust emission standards and modeled emission levels for 
MY 2024- 2027 generators assuming complete use of banked c redits 
under the Proposed Amendments . 
Displacement  category HC + NO x emission 
standard  
(g·kWh-1) HC + NO x emission level 
with credit use  
(g·kWh-1) 
< 50 cc  6.0 10.4 
50-80 cc, inclusive  6.0 8.5 
> 80 cc - < 225 cc  6.0 6.7 
225-825 cc, inclusive  3.0 3.8 
> 825 cc  0.80 0.80m 
Table III -3. Evaporative emission standards and modeled emission levels for 
MY 2024- 2027 generators assuming complete use of banked credits 
under the Proposed Amendments . 
Displacement  category Hot soak plus diurnal 
emission standard  
(g·test-1) Hot soak plus diurnal 
emission level with credit use  
(g·test-1) 
≤ 80 cc  0.50 0.68 
> 80 cc - < 225 cc  0.60 0.65 
≥ 225 cc  0.70 0.85 
In order to calculate emission reductions of the Proposed Amendments, SORE2020 
emission factors for nonpreempt  engines were adjusted to reflect the proposed 
emission standards and durability periods. Adjusted  zero- hour emission factors for 
SORE  (i.e., emission factors for engines at the beginning of their useful life)  were 
calculated by applying ratios of the prop osed emission standards to current emission 
standards. Adjusted  exhaust  emission deterioration factors were calculated by using 
the proposed durability period hours and adjusted  zero- hour emission factors. The 
zero- hour emission factors were set and emissions were assumed to deteriorate to  
levels equivalent to the proposed emission standards in the time of the durability 
period. The increased adoption of  ZEE was incorporated by setting emission factors to 
                                            
m No credit use was assumed as large spark -ignition engines in this displacement category have been 
subject to an equivalent emission standard since MY 2015.   
57 zero for MY 2024 and subsequent model years for all new  SORE equipment except 
generators and for MY 2028 and subsequent model years for generators.  There was 
no change in total equipment population or the amount of new equipment in any year, 
which means the equipment turnover rate was unchanged. This assumes that ZEE has 
the same lifetime as SORE equipment.  This assumption has no effect on emissions 
(because any ZEE at the end of their lifetime would be replaced with ZEE), but is the 
most economically conservative assumption. As explained in section I. E.2 of this 
report, the useful lifetime of  ZEE is expected to be as long as the useful lifetime of  
SORE equipment, and may be longer.  
B. Emission Reductions in Support of the 2016 State SIP Strateg y 
The SORE2020 model output  include s two sets of emission reduction data. The first 
set is reductions based solely on the summer months each year. The second set is reductions averaged across all 12 months. These data sets serve different purposes. The summer emission reductions specific ally provide  a comparison to the expected 
emission reductions in the 2016 State SIP Strategy. E vaporative emissions peak in the 
warmest months . Tropospheric ozone, formed from photochemical, temperature -
sensitive reactions between NO
x and ROG , reaches  its hig hest concentrations in the 
summer , as well. Since the 2016 State SIP Strategy aims to reduce ozone 
concentrations, it is important to understand what any regulatory changes could achieve in those summer months. The annual average–emission reduction data set allows for further analysis as it relates to health effects  caused by exposure to  PM
2.5. In 
this Staff Report, both sets of SORE2020 data  will be discussed as they are relevant. 
Summer average  emission reductions will be specified as such . 
Table III-4 id entifies t he modeled summer average  NO x and ROG  emission benefits of 
the Proposed Amendments. Staff calculated emission benefits based on the difference in modeled emissions between the Baseline Scenario and Proposed Amendments 
scenario each year for the regulatory horizon  of 2023 t hrough 2043. Figures III-2 
and III-3 graphically show modeled summer average emissions of NO
x and ROG , 
respectively, for the B aseline Scenario and Proposed Amendments scenario. In the 
Baseline Scenario, NO x and ROG  emissions would increase year over year due to an 
increase in population of SORE equipment.  In 2031, the summer statewide emissions 
under the Baseline Scenario  are expe cted to be approximately 18.3 tpd of NO x and 
127.5 tpd of ROG. In 2043 , the summer statewide emission reductions are expected 
to be approximately 19.9 tpd of NO x and 135.0 tpd of ROG.  
The 2016 State SIP Strategy contains expected emission reductions from  SORE of 
36 tpd for ROG , and 4 tpd  of NO x, in 2031 (CARB,  2017b) . The total contribution of 
NO x and ROG  from SORE in summer in California is approximately 141 tons per day  in 
2021. This is approximately equal to the NO x and ROG  emissions from light -duty 
passenger cars, according to the most recent inventories, SORE2020 and EMFAC2021 (CARB, 2020 and 2021b) . Significant reductions in both NO
x and ROG  emissions 
would begin in calendar year 2025 under the Proposed Amendments, after emission 
standards are zero for most SORE equipment and significantly more stringent for 
generators . For emissions modelling, it was assumed that once emission standard s of  
58 zero went into effect, all new equipment purchased would have zero emissions. 
Lifetimes of equipment were assumed to be the same as in the Baseline Scenario to be 
most conservative. Section II.B.1 includes a more detailed description of equipment 
lifetimes. Emission benefits would continue to increase as more SORE  equipment  
reach ed the end of their life and were  replaced with ZEE. In 2031, the summer 
statewide emission reductions are  expe cted to be approximately 7.9 tpd of NO x and 
64.5 tpd of ROG. These represent 43  and 51 percent reductions of NO x and ROG, 
respectively, compared to the B aseline Scenario  and exceed the expected emission 
reductions from SORE in the 2016 State SIP Strategy . By 2043, summertime statewide 
NO x and ROG  emissions from SORE equipment would  not reach zero but would be 
approximately 6.4 tpd and 31 tpd, respectively. The remaining emissions would be  
produced by  engines that are used in federally -regulated construction and farm 
equipment or vehicles under 175 horsepower that a re included in the SORE2020 
model but are preempt and not subject to  the SORE regulation s.   
59 Table III-4. Summer  average  emission reductions under  the 
Proposed Amendments. 
Calendar year  ROG emission 
reductions (tpd) NO x emission 
reductions (tpd) 
2023  0.0 0.0 
2024  3.9 0.5 
2025  12.7 1.4 
2026  23.0 2.5 
2027  33.2 3.6 
2028  42.5 4.7 
2029  50.8 5.8 
2030  58.2 6.9 
2031  64.5 7.9 
2032  70.0 8.7 
2033  74.8 9.5 
2034  79.3 10.2 
2035  83.5 10.8 
2036  87.3 11.4 
2037  90.8 11.8 
2038  93.8 12.2 
2039  96.5 12.6 
2040  98.7 12.8 
2041  100.7  13.1 
2042  102.4  13.3 
2043  103.9  13.5 
Average  65.3 8.3  
60 Figure III-2. Summer average NO x emissions under  the Proposed Amendments 
and the B aseline Scenario.  
  
 
Figure III -3. Summer average ROG  emissions under  the Proposed Amendments 
and the Baseline Scenario . 
 
 
61 The modelling results indicate that the Proposed Amendments would result in 
emission reductions from SORE that exceed the expected emission reductions in the 
2016 State SIP Strategy ( 4 tpd of NO x and 36 tpd  of ROG in 2031 ). Table III- 5 shows 
that the Proposed Amendments would also result in emission reductions greater than those expected in the South Coast and San Joaquin Valley a ir basins in the 2016 State 
SIP Strategy. While the 2016 State SIP Strategy estimated the SORE measure would 
achieve 2 tpd of NO
x and 16 tpd of ROG emissions reductions in the South Coast Air 
Basin in 2031, the Prop osed Amendments would achieve emission reductions of 2.9 
tpd of NO x and 24.8 tpd of ROG in 2031.  For the San Joaquin Valley  Air Basin , the 
2016 State SIP Strategy included  an estimated  0.3 tpd of NO x emission reductions 
from SORE in 2031. The Proposed Amendments would achieve 0. 84 tpd of NO x 
emission reductions  in 2031. All reductions in emissions from the Proposed 
Amendments, including those that are beyond the estimate in the 2016 State SIP Strategy, will count towards the State’s aggregate emissions reduction commitment in 
2031. 
Table III-5. Comparison of summer average emission reductions under the 
Proposed Amendments to 2016 State SIP Strategy expected emissions 
for SORE  for the San Joaquin Valley and South Coast air b asins. 
Air Basin  Year 2016 State 
SIP Strategy expected NO
x emission 
reduction 
(tpd) Proposed 
Amendments NO
x emission 
reduction 
(tpd) 2016 State 
SIP Strategy expected ROG emission reduction  
(tpd) Proposed Amendments ROG emission reduction 
(tpd) 
South Coast  2023 0.7 0.00 7 0.00 
San Joaquin Valley  2025 0.2 0.15 - 1.3 
San Joaquin Valley  2031 0.3 0.84 - 6.5 
South Coast  2031 2 2.9 16 24.8 
Statewide  2031  4 7.9 36 64.5 
 
IV. Benefits Anticipated from t he Regulatory Action, Includ ing the 
Benefits or Goals Provided in t he Authorizing Statute  
The Proposed Amendments would update  CARB’s SORE regulation s to improve air 
quality, and to clarify and improve the regulations for increased manufacturer 
flexibility, while reaching lower emission levels and maintaining enforceability . The 
benefits of the Proposed Amendments would include emission reductions, monetary 
savings in ongoing costs , and improved health outcomes.  The Proposed Amend ments 
would help meet  the goals in  the 2016 State SIP Strategy, MSS, and EO  N-79-20.   
62 The SORE regulation s have been successful at reducing emissions over the last 
25 years. The P roposed Amendments would continue to improve the SORE  
regulation s to accomplish additional emission reductions and accelerate the adoption 
of ZEE  to help California attain  and maintain ambient air quality standards . The 
Proposed Amendments are designed to achieve the  expected emission reductions in 
the 2016 State SIP Strategy for SORE and would reduce  emissions of pollutants that 
have  multiple known adverse health effects. E missions of  NO x and ROG  from SORE 
contribute to three criteria air pollutants —ozone, PM, and NO 2—either directly (NO 2 
and PM) or indirectly (ozone , NO 2, and PM). As described in Chapter I, all of these 
criteria air pollutants have adverse health effects.  The Proposed Amendments would 
also reduce GHG emissions and petroleum use.  The Proposed Amendments are part 
of a portfolio of “ Strategies, in coordination with other State agencies, U.S. 
Environmental Protection Agency  and local air districts, to achieve 1 00 percent zero -
emission from off -road vehicles and equipment operations in the State by 2035,” as 
directed  in EO N-79-20 (California Executive Order No. N -79-20, 2020).  
The following sections provide detailed descriptions of emission reduction benefits, a s 
well as benefits for professional and residential users, of the Proposed Amendments. 
The benefits for individuals include health benefits that would resul t from the emission 
reductions  under the Proposed Amendments.  
A. Emission Benefits  
Emission benefits a nd 2016 State SIP Strategy expected emissions reductions a re 
discussed in Chapter III.B of this Staff Report.  The emission reductions discussed in 
that section are for summer average emissions for May through October . However, 
emission reductions would  occur year round. This chapter discusses  the annual 
average emission reductions because these values are used in the calculation of health benefit s. Significant reductions in both NO
x and ROG  emissions would begin in 
calendar year 202 5 under the Proposed Am endments. For emissions modelling, it was 
assumed that once emission standard s of zero go into effect, all new equipment 
purchased would have zero emissions. Useful lifetimes of equipment were assumed to be the same as in the Baseline Scenario to be most conservative. Section I. E.2.c 
includes a more detailed description of equipment useful lifetimes. Under the 
Proposed Amendments, the emission reduction benefits would continue to increase as 
more SORE  equipment  reach es the end of their life and are  replaced  with ZEE. In 
2031, the statewide  annual  average  emission reductions are expected  to be 
approximately 7.4 tpd of NO
x and 55 tpd of ROG . These are 43 and 51 percent 
reductions of NO x and ROG, respectively, compared to current SORE emissions.  
Section IV.A.1  provides a more detailed review of the emission reduction benefits 
under the Proposed Amendments. S ection  IV.A.2  includes an estimate of additional 
ROG emission reductions from the decreased filling o f PFC  with gasoline . 
1. Anticipated Emission Reduction B enefits from the Proposed Amendments  
Table IV-1 identifies the modeled  annual average  ROG , NO x, and CO 2 emission 
benefits from  the Proposed Amendments.  CO 2 emission reductions are shown in  
63 million s of metric tons per year (MMT/year).  Staff calculated emis sion benefits based 
on the difference in modeled emissions between the Baseline Scenario and Proposed 
Amendments scenario each year for the regulatory horizon  of 2023 through  2043. 
Figures IV-1 and IV- 2 graphically show the modeled emissions o f NO x and ROG , 
respectively, for the B aseline Scenario and Proposed Amendments scenario. In the 
Baseline S cenario, NO x and ROG  emissions increase year over year due to an increase 
in population of SORE equipment.  
Significant reductions in both NO x and ROG  emissions would begin in calendar year 
2025 under the Proposed Amendments. Under the Proposed Amendments, emission 
benefits continue to increase  as more SORE  equipment  reach the end of their life and 
are replaced with ZEE. In 2031, the reductions are expected  to be approximately 7.4 
tpd of NO x and 55 tpd of ROG. These are  43 percent and 51 percent reductions of 
NO x and ROG, respectively, compared to the B aseline Scenario . The  total emission 
reductions from 202 3 through  2043 as a result of the Proposed Amendments are 
approximately 59,307 tons of NO x and 423,240 tons of ROG compared to the B aseline 
Scenario . By 2043, NO x and ROG  emissions would  not reach zero but would be 
approximately 6.2 tpd  and 27 tpd, respectively. Th e remaining emissions would be  
produced by  engines that are used in federally -regulated construction and farm 
equipment or vehicles under 175 horsepower that a re included in the SORE2020 
model but are preempt and not subject to  the SORE regulation s.  
The Proposed Amendments would  significantly reduce criteria air pollutant emissions 
to achieve 2016 State SIP Strategy expected emission reductions and create 
associated health benefits. S etting more stringent criteria air pollutant emission 
standards would  also result in GHG emission reductions as ZEE continues to account 
for a greater fraction of  small off -road equipment.  Total modeled CO 2 emission 
reductions compared to the Baseline Scenario  for 2023 through  2043 under the 
Proposed Amendments are  15 million tons. As illustrated in Table IV-1 , CO 2 emission 
reductions would begin in 2024 and increase in each subsequent year.   
64 Table IV-1. Annual average emission reductions under  the Proposed Amendments.  
(Totals may not add up due to rounding.)  
Year ROG emission 
reductions (tpd)  NO x emission 
reductions (tpd)  CO 2 emission 
reductions 
(MMT/year ) 
2023  0.00 0.00 0.00 
2024  3.3 0.46 0.05 
2025  10.9 1.4 0.13 
2026  19.7 2.4 0.23 
2027  28.4 3.4 0.31 
2028  36.3 4.4 0.40 
2029  43.4 5.5 0.48 
2030  49.6 6.5 0.57 
2031  55.0 7.4 0.64 
2032  59.6 8.2 0.71 
2033  63.7 8.9 0.77 
2034  67.4 9.6 0.82 
2035  70.8 10.1 0.87 
2036  73.9 10.7 0.91 
2037  76.7 11.1 0.94 
2038  79.1 11.5 0.97 
2039  81.2 11.8 1.0 
2040  83.0 12.0 1.0 
2041  84.6 12.3 1.0 
2042  85.9 12.5 1.1 
2043  87.1 12.6 1.1 
Average  55.2 7.7 0.66 
Total  423,240  59,307  13.9 
  
65 Figure IV -1. Annual average NO x emissions under  the Proposed Amendments and 
the Baseline Scenario . 
 
Figure IV -2. Annual average ROG emissions under  the Proposed Amendments and 
the Baseline Scenario . 
 
To demonstrate  that differences in the total amount of banked credits would  not 
significantly change  the outcome of the emissions analysis, a sensitivity analysis was 
 
66 performed. Two scenarios were modeled —one with no banked credits , and one with 
twice the amount of banked  credits that manufacturers held at the end of MY 2018. 
For the  scenario  with no banked credits, all MY 2024 equipment were  assumed to be 
compliant with the more stringent HC + NO x emission standard s. In this scenario, 
summer  emission reductions in 2031  would be  8.0 tpd and 65 tpd of NO x and ROG , 
respectively. These NO x and ROG  emission reductions are 0.1 and 0.5 tpd higher, 
respectively, than those expected for the Proposed Amendments scenario . 
For the  scenario  with twice the amount of banked credits that manufacturers held at 
the end of MY 2018, all banked credits were assumed to be fully used between MY s 
2024 and  2027 for generators. The emission rates used for this scenario  are shown in 
Tables I V-2 and IV-3 . This scenario  would result in summer emission reductions in 2031 
of 7.7 tpd and 64 tpd of NO x and ROG , respectively. These NO x and ROG  emission 
reductions are 0. 2 tpd and 0.5 tpd lower , respectively,  than those expected for the 
Proposed Amendments scenario . 
Table IV-2. MY 2024- 2027 generator exhaust emission standards and emission 
rates  under  the Proposed Amendments with twice the amount of 
banked  emission credit s that manufacturers held at the end of 
MY 2018. 
Displacement  category Emissions 
durability period  
(hours) HC + NO
x 
emission standard  
(g·kWh
-1) HC + NO x 
emission level  
with credit  use 
(g·kWh-1) 
< 50 cc  500 6.0 14.9 
50-80 cc, inclusive  500 6.0 10.9 
> 80 cc - < 225 cc  500 6.0 7.3 
225-825 cc, inclusive  1,000 3.0 4.6 
> 825 cc  1,000 0.80 0.80  
67 Table IV-3. MY 2024- 2027 generator evaporative e mission standards and emission 
rates  under  the Proposed Amendments with twice  the amount of 
banked emission credits that manufacturers held at the end of 
MY 2018. 
Displacement  
category Hot soak plus 
diurnal 
emission 
standard   
(g·test-1) Hot soak plus 
diurnal 
emission level  
with credit  use  
(g·test-1) Hot soak 
emission level  
with credit use  
(g·test-1) Diurnal 
emission 
level with 
credit use  
(g·test-1) 
≤ 80 cc  0.50 0.86 0.31 0.55 
> 80 cc - < 225 cc  0.60 0.70 0.02 0.68 
≥ 225 cc  0.70 1.0 0.21 0.79 
2. Additional Emission Benefits  
A decrease in use of PFCs may result in greater  ROG emission reductions than those 
calculated by the SORE2020 model. PFCs are used to transport gasoline from 
dispensing facilities (e.g., convenience stores and service stations) to SORE equipment. PFCs are a source of ROG emissions when they are being filled at the dispensing facilities, while they are being used to store fuel, and when they are used 
to fill SORE fuel tanks. Because of increased adoption of  ZEE, staff expect s a 
decreased need for PFC use, which would lead to further ROG emission reductions.  
It is possible to estimate the ROG emission r eductions from the  decreased  fueling of 
PFCs at gasoline dispensing facilities (GDFs) by combining several fueling emission 
factors with the reduction in gasoline use from the direct cost analysis. CARB has 
established emission factors for several aspects of fueling, including transfer of 
gasoline from a cargo tanker to the GDF storage tank (Phase I transfers) and from the storage tank to the vehicle (Phase II transfers)  (CARB, 2013). The analysis assumed that 
all PFCs are fueled at GDFs that are equipped with underground storage tanks and Phase II enhanced vapor recovery controls.
n The emission factors can be added to 
estimate potential emission reductions at GDFs as 8.82 pounds of ROG emitted per 
                                            
n In 2000, CARB approved Enhanced Vapor Recovery (EVR) regulations for GDFs equipped with 
underground storage tanks. The EVR regulations were enacted to achieve additional emission 
reductions and to increase equipment reliability by adopting nearly 80 new performance standards or 
specifications and increasing testing requirements. Not all GDFs throughout California are required to 
install Phase  II EVR controls. Using the emission factors for GDFs with underground storage tanks and 
Phase II EVR controls provides a conservative emission reduction estimate, i.e. , one that may under -
estimate the total emission reduction benefit of the Proposed Amendments from the filli ng of PFCs at 
GDF.   
68 thousand gallons of gasoline dispensed.o The reduction in gasoline dispensed as a 
result of the Proposed Amendments is based on total population of SORE equipment 
in a given year and usage rates for equipment per category, as described in 
section  C.1.d of the SRIA in Appendix I of this Staff Report. Combining these values 
yields a ROG emission reduction beyond the reductions reported via SORE2020. The ROG emission reductions from reduced fuel dispensing are calculated as 1.3 tpd and 
2.6 tpd for 2031 and 2043, respectively. In sum, 11,600 tons of ROG emissions from 
filling PFCs for fueling SORE equipment would be avoided over the regulatory horizon  
of 2023 through  2043.  Further ROG emission reductions due to permeation from the 
PFCs, spillage, and fueling the SORE equipment are also likely but cannot be 
quantified at this time.  
B. Benefits to Typical Businesses  
Chapter VII  discusses all costs directly from a  user perspec tive. Here, typical 
businesses are considered to be all affected businesses in California that are not small businesses (e.g. , businesses that own and use small off -road equipment to maintain 
their property). A substantial benefit to typical businesses across the state would  be 
the increased durability of the small off -road equipment they purchase. The Proposed 
Amendments increase the durability requirements for SORE starting in MY 2024. While the emissions durability period  is not a feature that is necessa rily advertised to 
consumers, staff expects longer durability periods would lead to longer useful lifetimes 
for products.  This would benefit  business users of SORE equipment, such as those 
using generators during  PSPS or other unexpected power outages.  
ZEE batteries frequently outlive the lifetime of equipment. The first purchase of ZEE 
requires purchasing sufficient batteries for use time (e.g., an eight -hour work day) . This 
is a significant contributor to the upfront cost for professional -grade equipment . ZEE 
batteries can often be used in several products within a manufacturer’s family of ZEE. Subsequent equipment purchases may require fewer batteries, therefore lowering the 
purchase price significantly. In this analysis, upfront equipment prices have be en 
assumed to be constant and include battery costs, as staff has  no way of tracing which 
equipment purchases are new versus subsequent . This creates the most conservative 
estimate. Maintenance is also much less intensive and required  less frequently on ZE E. 
For example , the owner’s manual of a professional -grade SORE lawnmower 
recommends changing the oil after the first 20 hours of use, and after every 100 hours thereafter. It also recommends changing the spark plug and air filter after 200 hours of 
use ( Honda, 2021 ). An equivalent professional -grade ZEE lawnmower does not have 
                                            
o The following emission factors (CARB, 2013) in pounds of ROG emitted per thousand gallons gasoline 
dispensed (lbs/kgal) were added to estimate emission reductions that would occur at GDFs under the 
Proposed Amendments: (a) To estimate emissions while PFCs are open at GDFs: 8.4 lbs/kgal, the 
uncontrolled emission factor used to characterize Phase II fueling of vehicles that do not have onboard refueling vapor recovery systems; and (b)  To estimate other GDF emissions that would be reduced if 
less gasoline  were dispensed to PFCs: ( i) 0.15 lbs/kgal for Phase I “revised EVR” bulk transfer losses, 
(ii) 0.24 lbs/kgal for Phase II “revised EVR” nozzle spillage, (iii)  0.009 lbs/kgal for Phase II “EVR Year 
2017” hose permeation, and (iv)  0.024 lb s/kgal for “revised EVR” pressure driven losses.   
69 these maintenance r equirements.  The only maintenance requirements are replacing or 
sharpening the blade and cleaning (Greenworks, 2021a), b oth of which are also 
required of a SORE lawn mower.  Having more durable equipment that is not taken out 
of service for maintenance reduces the need for backup equipment and spare parts. 
Owners of ZEE would  save time by not having to travel to a gasoline dispensing facility 
and fill PFCs with fue l for their SORE equipment. They will also not need to purchase 
replacement or extra PFCs.  
C. Benefits to Small Businesses  
Chapter VII  discusses all costs directly from a  user perspective. Examples of small 
businesses that would  be affected by the Proposed Amendments are landscapers, 
both licensed and unlicensed. The benefits to these businesses would  be similar to 
those discussed in the typical business section, including more reliable ZEE, lower  
maintenance costs, and less freq uent replacement  of equipment.  
D. Benefits to Individuals  
Individuals are all those who live in the state of California, regardless of whether or not they own small off -road equipment . Benefits to individuals from the Proposed 
Amendments would include a reduction in adverse health outcomes due to emission 
reductions. The estimated value of the accrued  statewide health benefit derived from 
criteria emission reductions is approximately $8.82 billion, with $8.80 billion resulting from reduced premature mo rtality and $17.2 million resulting from reduced 
hospitalizations and ER visits for asthma.  Section IV.D.1  describes the health benefits 
model and results. S ection  IV.D.2  describes adverse health impacts of emission from 
SORE. Section  IV.D. 3 discusses the valuation of these health benefits. S ection  IV.D. 4 
describe s the valuation of reduced CO
2 emissions from the Proposed Amendments.  
1. Health Benefits  
a. Background on Health Benefits and Model  
The Proposed Amendments would reduce NO x, and PM 2.5 emissions,  resulting in 
health benefits for individuals in California . The value of  health benefits calculated for 
the amendments include  fewer instances of premature mortality and fewer hospital 
and ER visits  for asthma . The health benefits evaluation method used in this analysis is 
the same as the one used for the Advanced Clean Truck Regulation and the 2018 
amendments to the  Low Carbon Fuel Standard  (CARB, 2018a and 2019b) .  
CARB analyzed the value associated with four health outcomes in the Baseline  
Scenario , Proposed Amendments, and regulatory alternatives: cardiopulmonary 
mortality, hospitalizations for cardiovascular illness, hospitalizations for respiratory 
illness, and ER visits for asthma.  These health outcomes and others have been 
identified by  U.S. EPA as  having a causal or likely causal relationship with exposure to 
PM 2.5 based on a substantial body of evidence (U.S. EPA, 2019a ). 
U.S. EPA has determined that both long -term and short- term exposure to PM 2.5 play a 
causal  role in premature mortality, meaning  that a substantial body of scientific  
70 evidence shows a relationship between PM 2.5 exposure and increased risk of death. 
This relationship persists when other risk factors such as smoking rates, poverty and 
other factors are taken into account (U.S. EPA, 2 019a). 
U.S. EPA has also determined a causal  relationship between nonmortality 
cardiovascular effects and short and long -term exposure to PM 2.5 and a likely causal 
relationship between nonmortality respiratory effects and short and long -term PM 2.5 
exposure (U.S. EPA, 2019 a). These outcomes lead to hospitalizations and ER v isits for 
asthma , and are included in this analysis.  
CARB staff evaluated a limited number of statewide non cancer health impacts 
associated with exposure to PM 2.5 and NO x emissions from SO RE. NO x includes 
nitrogen dioxide, a potent lung irritant, which can aggravate lung diseases such as 
asthma when inhaled ( U.S. EPA, 2016 ). However, the most serious quantifiable impacts 
of NO x emissions occur  through the conversion of NO x to fine particles  of ammonium 
nitrate aerosol through chemical processes in the atmosphere. PM 2.5 formed in this 
manner is termed secondary PM 2.5. Both directly emitted PM 2.5 and secondary PM 2.5 
from heavy- duty vehicles is associated with adverse health outcomes, such as 
cardiopulmonary mortality, hospitalizations for cardiovascular illness and respiratory illness, and ER visits for asthma. As a result, reductions in PM
2.5 and NO x emissions are 
associated with reductions in these health outcomes. 
b. Incidence- Per-Ton Methodology  
CARB uses the incidence- per-ton (IPT) methodology to quantify the health benefits of 
emission reductions in cases where dispersion modeling results are not available. A description of this method is included on CARB’s webpage (CARB,  2019a ). CARB’s IPT 
methodology is based on a methodology developed by U.S.  EPA (Fann et al., 2009; 
Fann et al., 2012; Fann et al., 2018) .  
Under the IPT methodology, changes in emissions are app roximately proportional to 
changes in health outcomes.  IPT factors are derived by calculating the number of 
health outcomes associated with exposure to PM
2.5 for a baseline scenario using 
measured ambient concentrations and dividing by the emissions of PM 2.5 or a 
precursor. The calculation is performed separately for each air basin using the 
following equation:  
𝐼𝐼𝐼𝐼𝐼𝐼 =  𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛  𝑜𝑜𝑜𝑜 ℎ𝑛𝑛𝑒𝑒𝑒𝑒𝑒𝑒ℎ 𝑜𝑜𝑛𝑛𝑒𝑒𝑜𝑜𝑜𝑜𝑛𝑛𝑛𝑛𝑜𝑜  𝑖𝑖𝑛𝑛 𝑒𝑒𝑖𝑖𝑛𝑛 𝑛𝑛𝑒𝑒𝑜𝑜𝑖𝑖𝑛𝑛
𝑒𝑒𝑛𝑛𝑛𝑛𝑛𝑛𝑒𝑒𝑒𝑒  𝑛𝑛𝑛𝑛𝑖𝑖𝑜𝑜𝑜𝑜𝑖𝑖𝑜𝑜𝑛𝑛𝑜𝑜  𝑖𝑖𝑛𝑛 𝑒𝑒𝑖𝑖𝑛𝑛 𝑛𝑛𝑒𝑒𝑜𝑜𝑖𝑖𝑛𝑛 
Multiplying the e mission reductions from the Proposed Amendments in an air basin by 
the IPT factor then yields an estimate of the reduction in health outcomes achieved by 
the Proposed Amendments. For future years, the number of outcomes is adjusted to 
account for populatio n growth. CARB’s current IPT factors are based on a 2014- 2016 
baseline scenario, which represents the most recent data available at the time the current IPT factors were computed. IPT factors are computed for the two types of  
PM
2.5: primary PM 2.5 and secondary PM 2.5 of ammonium nitrate aerosol formed from 
precursors.    
71 c. Reduction in Adverse Health Impacts  
Table IV -4 shows the estimated total avoided premature mortality, hospitalizations, 
and ER visits for asthma  by California air basin  that would result from implementation 
of the Proposed Amendments from  2023 through 2043, relative to the Baseline 
Scenario . Only the air basins with values of one or higher are shown. The biggest 
health benefits would  occur in the South Coast and San Franc isco Bay Area a ir basins. 
Table IV -5 shows the estimated avoided health outcomes by year. As described in  
section  IV.A, the Proposed Amendments are estimated to reduce overall emissions of 
NO x and ROG  in every year starting in 2024, and lead to net reduction in adverse 
health outcomes statewide, relative to the  Baseline Scenario . Health benefits  would  
begin in 2024, and the reduction in incidents and deaths would continue to increase 
through  the end of the regulatory horizon  as more SORE equipment are  trans itioned 
to ZEE and more units are purchased. Overall, the mortality due to cardiopulmonary 
causes would  decrease by 892 over the regulatory horizon  under the Proposed 
Amendments.   
72 Table IV -4. Modeled regional and statewide avoided mortality and morbidity 
incidents from 2023 through 2043 u nder the Proposed Amendments, 
central estimatesp and 95  percent confidence intervals. 
(Totals may not add up due to rounding.)  
Air Basin  Avoided 
premature cardiopulmonary mortality  Avoided cardiovascular hospitalizations  Avoided acute respiratory hospitalizations  Avoided ER visits for 
asthma  
Lake County  1 (1 - 1) 0 (0 - 0) 0 (0 - 0) 0 (0 - 0) 
Mojave Desert  3 (3 - 4) 0 (0 - 1) 1 (0 - 1) 1 (1 - 2) 
Mountain 
Counties  5 (4 - 6) 0 (0 - 1) 1 (0 - 1) 2 (1 - 2) 
North Central 
Coast  4 (3 - 5) 1 (0 - 1) 1 (0 - 1) 2 (1 - 3) 
North Coast 1 (1 - 1) 0 (0 - 0) 0 (0 - 0) 0 (0 - 1) 
Sacramento Valley  31 (24 - 38) 4 (0 - 7) 5 (1 - 8) 12 (7 - 16) 
Salton Sea  3 (2 - 3) 0 (0 - 1) 0 (0 - 1) 1 (1 - 2) 
San Diego County  51 (40 - 62) 7 (0 - 14) 9 (2 - 15) 20 (13 - 28) 
San Francisco Bay Area  114 (89 - 140) 18 (0 - 35) 21 (5 - 38) 62 (39 - 85) 
San Joaquin Valley  56 (44 - 68) 7 (0 - 13) 8 (2 - 14) 20 (13 - 28) 
South Central Coast  18 (14 - 21) 3 (0 - 5) 3 (1 - 6) 8 (5 - 10) 
South Coast  605 (473 - 739) 101 (0 - 199) 121 (28 - 213) 308 (195 - 421) 
Statewide  892 (697 - 1090)  142 (0 - 278) 169 (40 - 298) 438 (277 - 599) 
                                            
p The health benefits modeling is done using an incidence- per-ton methodology allowing for 95 percent 
confidence intervals and a central estimate to be calculated.   
73 Table IV -5. Annual statewide avoided mortality and morbidity incidents under the  
Proposed Amendments , central estimates and 95 percent confidence 
intervals . 
(Totals may not add up due to rounding.)  
Year Avoided 
premature cardiopulmonary mortality  Avoided cardiovascular hospitalizations  Avoided acute respiratory hospitalizations  Avoided ER visits 
for asthma  
2023 0 (0 - 0) 0 (0 - 0) 0 (0 - 0) 0 (0 - 0) 
2024 2 (2 - 3) 0 (0 - 1) 0 (0 - 1) 1 (1 - 2) 
2025 8 (6 - 10) 1 (0 - 2) 1 (0 - 2) 4 (3 - 5) 
2026 14 (11 - 17) 2 (0 - 4) 2 (1 - 4) 7 (4 - 10) 
2027 20 (16 - 24) 3 (0 - 6) 3 (1 - 6) 10 (6 - 14) 
2028 26 (20 - 32) 4 (0 - 7) 4 (1 - 8) 13 (8 - 18) 
2029 31 (24 - 38) 5 (0 - 9) 6 (1 - 10) 16 (10 - 22) 
2030 36 (28 - 44) 5 (0 - 11) 7 (2 - 12) 18 (12 - 25) 
2031 41 (32 - 50) 6 (0 - 12) 7 (2 - 13) 20 (13 - 28) 
2032 45 (35 - 55) 7 (0 - 14) 8 (2 - 15) 22 (14 - 31) 
2033 49 (38 - 59) 8 (0 - 15) 9 (2 - 16) 24 (15 - 33) 
2034 52 (41 - 63) 8 (0 - 16) 10 (2 - 17) 26 (16 - 35) 
2035 55 (43 - 67) 9 (0 - 17) 10 (2 - 18) 27 (17 - 37) 
2036 58 (45 - 70) 9 (0 - 18) 11 (3 - 20) 28 (18 - 39) 
2037 60 (47 - 73) 10 (0 - 19) 12 (3 - 20) 29 (19 - 40) 
2038 62 (48 - 76) 10 (0 - 20) 12 (3 - 21) 30 (19 - 41) 
2039 64 (50 - 78) 10 (0 - 20) 12 (3 - 22) 31 (20 - 42) 
2040 65 (51 - 80) 11 (0 - 21) 13 (3 - 23) 32 (20 - 43) 
2041 67 (52 - 82) 11 (0 - 22) 13 (3 - 23) 32 (20 - 44) 
2042 68 (53 - 83) 11 (0 - 22) 13 (3 - 24) 33 (21 - 45) 
2043 69 (54 - 85) 11 (0 - 23) 14 (3 - 24) 33 (21 - 46) 
Total  892 (697 - 1090)  142 (0 - 278) 169 (40 - 298) 438 (277 - 599) 
Because CARB staff  is evaluating a limited number of health impacts  (premature 
cardiopulmonary mortality, cardiovascular hospitalizations, respiratory hospitalizations, 
and ER visits  for asthma ), the full health benefits of the Proposed Amendments are 
expected to be underestimated. An expansion of the assessment of outcomes, including, but not limited to, reduction of additional cardiovascular and respiratory illnesses, nonfatal/fatal cancers, and lost work days would provide a more complete picture of the benefits from reduced exposure to air pollution. Additionally, CARB’s 
mortality and illness assessment is only calculated for a portion of emissions that lead  
74 to primary and secondary PM 2.5, and  there are other pollutants that can cause health 
issues. For instance, while NO x can lead to the formation of secondary PM 2.5 particles, 
NO x can also react with other compounds to form ozone, which can cause respiratory 
problems. And SORE can also emit TACs, some of which have been determined to 
cause cancer. Altogether, CARB’s current PM 2.5 mortality and illness evaluation 
represents only a portion of the benefits of the Proposed Amendments.  
d. Potential Future Evaluation of Additional Health Benefits  
While CARB’s PM 2.5 mortality and illness valuation has been, and continues to be, a 
useful method for valuing the health benefits of regulations, it only represents a portion of those benefits. The basis for CARB’s current methodology was documented in Appendix J of the Initial Statement of Reasons for CARB’s 2010 Truck and Bus 
Regulation  (CARB 2010); since then, there have been additional scientific evidence 
and updated analysis methods showing more ways of evaluating the health benefits of 
reducing air pollution. Thus,  the full health benefits of the Proposed Amendments are 
underestimated because not all the adverse health outcomes associated wit h PM
2.5 
and additional pollutants such as air toxics are evaluated and monetized. Also, CARB’s current evaluation methodology does not take into account all PM
2.5 precursor 
emissions. An expansion of the emissions inputs and an assessment for other health outcomes, including, but not limited to, additional cardiovascular and respiratory 
illnesses, nonfatal/fatal cancers, nervous system diseases, and lost work days would 
provide a more complete picture of the benefits from reduced exposure to air pollution. In 2021, EPA issued a Technical Support Document (TSD) for their 
Cross -State Air Pollution Rule that provided both health functions and health valuation 
for lung cancer incidence, Alzheimer’s disease, and Parkinson’s disease, among other health endpoints r elated to PM
2.5 exposures (U.S. EPA, 2021 b).  
CARB’s mortality and illness valuation is just for PM 2.5, but there are other pollutants 
that can cause health issues. For instance, NO x reacts with other compounds to form 
ozone, which can then cause respirato ry problems. Updated health impact functions 
and valuation for ozone are also provided in the aforementioned Cross- State Air 
Pollution Rule TSD provided by the U.S. EPA (U.S. EPA, 2021 b). Additionally , some of 
the TACs emitted from SORE can lead  to cancers.  
Expanding CARB’s health evaluation and economic valuation methodology to include any of the above additional inputs and health outcomes would allow the public to reach a better understanding of the benefits from reducing air pollution by movin g 
toward zero -emission technologies.  
The scientific literature has demonstrated the broad impacts of exposures to pollution, which go beyond what CARB staff has quantified in Tables IV -4 and IV -5 and are thus  
summarized in the next section. 
2. Adverse Impacts to Human Health from SORE Emissions  
SORE equipment represents a growing source of pollution emissions and health burdens that adversely affect communities in multiple ways. For instance, it has been  
75 projected that the nationwide PM 2.5 health burden from b oth commercial and 
residential lawn and garden equipment may rise a pproximately 50% in 2025 compared 
to 2011 (Davidson et al., 2020). This section provides additional information to 
supplement and build on the discussion of quantified health impacts.  
a. Particle Pollution Impacts  
Gaseous pollutant s that are  emitted by SORE equipment include NO x, which can lead 
to the formation of ozone and the secondary  formation of PM, including PM 2.5 (World 
Health Organization,  Europe, 2006). Due to their small  particle  sizes, PM 2.5 in air can 
reach the lower respiratory tract and potentially pass into the bloodstream to affect other organs  (CARB, 2021h ; U.S. EPA , 2021c ). By this means, PM
2.5 air pollution leads 
not only to increased cancer risk, but it also causes respi ratory and cardiovascular 
diseases and even premature death; adverse health outcomes from PM 2.5 include 
asthma, chronic heart disease, and heart attack  (CARB, 2021h; U.S. EPA , 2019a ; U.S. 
EPA, 2021c ; World Health Organization,  Europe, 2013) . Moreover, PM 2.5 air pollution 
can result in respiratory, cardiac, and mortality effects over short periods of exposure 
such as hours, days, or weeks ( U.S. EPA, 2019 a). Exposures to PM 2.5 may also lead to 
myriad other health outcomes, including metabolic, nervous system,  reproductive, and 
developmental effects  (U.S. EPA, 2019 a). For example, adverse health conditions with 
possible links to airborne PM 2.5 include high blood pressure, insulin resistance, and 
other risk factors for Type II Diabetes, as well as psychological/cognitive problems  
(U.S. EPA, 2019 a). PM 2.5 may especially impact women and children via health effects 
such as pre- term birth, reduced birth weight, and abnormal lung and cardiovascular 
development  (U.S. EPA, 2019 a).  
In addition to its ability to increas e risk for diseases, PM 2.5 is also well known to 
exacerbate underlying illnesses such as asthma, bronchitis, and heart disease  (U.S. 
EPA, 2019a) . As a result, the health impacts of PM 2.5 are typically studied not only 
using cancer diagnoses and the rates of onset for lung and cardiovascular diseases, but also via metrics on respiratory symptoms (e.g., cough, wheeze, asthma medication 
usage), measures of abnormal lung and heart functioning (e.g., reduced lung volume, irregular heartbeat), plus rates of hosp italizations, ER visits, and restricted activity days 
associated with worsening of chronic lung and heart diseases.  
b. Ozone Pollution Impacts  
 NO
x emissions from SORE equipment can  also react with other compounds to form 
ozone, which is the main component  of photochemical smog. Based on the extent of 
evidence from scientific studies, U .S. EPA has determined that short -term exposure to  
ozone is causally linked to adverse respiratory effects ( U.S. EPA, 2020) . Ozone can 
cause irritation  of and damage to lung tissue, worsening of  asthma and chronic 
illnesses including chronic obstructive pulmonary disease (COPD) and reduced lung function. For instance, a study conducted in the San Joaquin Valley showed that increased ozone pollution led to increased risk for ER  visits  for asthma , especially for 
children and Black residents (Gharibi et al., 2018) . Metabolic functions are also likely to 
be affected by short- term ozone pollution, such as those leading to increased risk for 
complications and hospitalizations in diabetic individuals  (U.S. EPA, 2020 ). Similar to  
76 PM 2.5, other potential health effects from ozone exposure include impacts on the 
cardiovascular, nervous, and reproductive systems, and even increased risk of 
mortality ( U.S. EPA, 2020) .  
c. Conclusion  
SORE equipment generate criteria pollutants that are known to cause serious health 
impacts. Section E of this chapter IV provides a discussion of additional health impacts 
from exposures to noise and TACs. As shown in Tables IV -4 and IV -5, CARB estimates 
that implementation of the Proposed Amendments would result in substantial health 
benefits, due to reduced cardiovascular/respiratory hospitalizations, ER visits  for 
asthma , and premature cardiopulmonary mortality. CARB’s assessment is limited and 
thus likely an underestimation, because it does not consider the various other health 
outcomes that could be avoided with ZEE and lower -emitting  SORE equipment.  
Furthermore, with the growing health impact of  SORE  equipment , such as lawn and 
garden equipment, actions like the Proposed Amendments to increase and accelerate 
adoption of ZEE  are critically important.  
3. Economic Impact of Health Benefits  
In accordance with U.S . EPA practice, health outcomes are monetized by multiplying 
each incident by a standard value derived from the economic studies. The value per 
incident is provided  in Table IV-6. Values are in 2019 dollars (2019$) and do account 
for future inflation.  The value for avoided premature mortality is based on willingness 
to pay, which is a statistical construct based on the aggregated dollar amount that a 
large group of people would be willing to pay for a reduction in their individual risks of dying in a year . The economic value associated with reduced premature mortality is a 
key benefit of the Proposed Amendments. This benefit , however , does not correspond 
to direct changes in expenditures for households and businesses and is not included in 
the macroeconomic modeling ( Chapter  VII). Because  avoided hospitalizations and ER  
visits for asthma  correspond to reductions in household expenditures on health care, 
these values are included in the macroeconomic modeling .  
Unlike mortality valuation, the savings for avoided hospitalizations and ER  visits  for 
asthma  are based on a combination of typica l costs associated with hospitalization and 
the willingness of surveyed individuals to pay to avoid adverse outcomes that occur 
when hospitalized . These include hospital charges, post -hospitalization medical care, 
out-of-pocket expenses, and lost earnings of both individuals and family members, lost 
recreation value, and lost household production (e.g., valuation of time- losses from 
inability to maintain the household or provide childcare) . These monetized benefits 
from avoided hospitalizations and ER  visits for asthma  are included in the 
macroeconomic modeling ( Chapter  VII).   
77 Table IV-6. Valuation per incident for avoided health outcomes (2019$) . 
Outcome  Value per incident  
Premature  cardiopulmonary m ortality  $9,865,659  
Cardiovascular hospitalization $58,275  
Acute respiratory hospitalization $50,831  
ER visit for asthma  $834  
Staff calculated the statewide valuation of health benefits by multiplying the value per 
incident in Table IV-6 by the annual number and type of incidents. Table IV-7 p rovides 
annual totals. Table IV-8 provides a summarized total throughout  the regulatory 
horizon . The estimated  value of the  accrued  statewide health benefit derived from 
criteria emission reductions  over the regulatory horizon  is approximately $8.82 billio n, 
with $8.80 billion resulting from reduced premature mortality and $17.24 million 
resulting from reduced hospitalizations and ER visits  for asthma . The spatial 
distribution of these benefits across the state follows the distribution of the health 
impacts  by air basin as described in Table IV-4.  
78 Table IV-7. Annual valuation of avoided health outcomes under the Proposed 
Amendments (million 2019 $). 
Year Avoided 
premature cardiopulmonary  
mortality valuation  Avoided cardiovascular hospitalization valuation  Avoided acute respiratory hospitalization valuation  Avoided ER visit for 
asthma valuation  Annual total valuation  
2023 $0.00  $0.00  $0.00  $0.00  $0.00  
2024 $19.73  $0.00  $0.00  $0.00  $19.73  
2025 $78.93  $0.06  $0.05  $0.00  $79.04  
2026 $138.12  $0.12  $0.10  $0.01  $138.34  
2027 $197.31  $0.17  $0.15  $0.01  $197.65  
2028 $256.51  $0.23  $0.20  $0.01  $256.95  
2029 $305.84  $0.29  $0.30  $0.01  $306.45  
2030 $355.16  $0.29  $0.36  $0.02  $355.83  
2031 $404.49  $0.35  $0.36  $0.02  $405.21  
2032 $443.95  $0.41  $0.41  $0.02  $444.79  
2033 $483.42  $0.47  $0.46  $0.02  $484.36  
2034 $513.01  $0.47  $0.51  $0.02  $514.01  
2035 $542.61  $0.52  $0.51  $0.02  $543.67  
2036 $572.21  $0.52  $0.56  $0.02  $573.32  
2037 $591.94  $0.58  $0.61  $0.02  $593.16  
2038 $611.67  $0.58  $0.61  $0.03  $612.89  
2039 $631.40  $0.58  $0.61  $0.03  $632.62  
2040 $641.27  $0.64  $0.66  $0.03  $642.60  
2041 $661.00  $0.64  $0.66  $0.03  $662.33  
2042 $670.86  $0.64  $0.66  $0.03  $672.19  
2043 $680.73  $0.64  $0.71  $0.03  $682.11  
Total  $8,800.17  $8.28  $8.59  $0.37  $8,817.40   
79 Table IV-8. Statewide valuation from avoided health outcomes under the Proposed 
Amendments. 
Outcome Avoided incidents  Valuation 
(million 2019 $) 
Premature cardiopulmonary mortality  892 $8,800.17  
Cardiovascular hospitalization  142 $8.28 
Acute respiratory hospitalization  169 $8.59 
ER visit for asthma  439 $0.37 
Total  1,642 $8,817. 40 
4. Social Cost of Carbon  
The Proposed Amendments will significantly reduce criteria air pollutants to achieve 
CARB’s 2016 State SIP Strategy expected emission reductions a nd associated health 
benefits. By setting more stringent criteria air pollutant emission standards , there  will 
also be associated  GHG emission reductions due to  increased adoption of ZEE . The 
benefit of these GHG reductions can be estimated using the Social Cost of Carbon 
(SC-CO 2), which provides a dollar valuation of the damages caused by one ton of 
carbon pollution and represents the monetary benefit today of reducing carbon 
emissions in the future .  
In this analysis, CARB utilizes the current Interagency Working Group (IWG) supported SC-CO
2 values to consider the social costs of actions taken to reduce GHG  emissions 
as described in the National Academies of Science, Engineering, and Medicine 
(NASEM) report  (NASEM , 2017) . This is consistent with the approach presented in 
California’s 2 017 Climate Change Scoping Plan (CARB, 2017 a), with U.S. Presidential  
Exec utive Order 12866 and the O ffice of Management and Budget (OMB)  Circular A -4 
of September  17, 2003, and reflects the best available science in the estimation of the 
socio- economic impacts of carbon  (OMB, 2003) .  
IWG describes SC -CO 2 as follows:  
The social  cost of carbon (SC -CO 2) for a given year is an estimate, in dollars, of 
the present discounted value of the future damage caused by a 1- metric ton 
increase in carbon dioxide (CO 2) emissions into the atmosphere in that year, or 
equivalently, the benefits of reducing CO 2 emissions by the same amount in 
that year. The SC -CO 2 is intended to provide a comprehensive measure of the 
net damages – that is, the monetized value of the net impacts – from global 
climate change that result from an additional ton of CO 2. 
These damages include, but are not limited to, changes in net agricultural 
productivity, energy use, human health, property damage from increased flood risk, as well as nonmarket damages, such as the services that natural ecosystems  
80 provide to society. Many of these damages from CO 2 emissions today will affect 
economic outcomes throughout the next several centuries. (NASEM, 2017)  
Table IV-9 presents the range of IWG SC -CO 2 values used in regulatory assessments, 
including California’s 2017 Climate Change Scoping Plan  (CARB, 2017a) . 
Table IV-9. Social cost of carbon 2020- 2040 (2007$ per metric ton) . 
Year 5 Percent  
Discount Rate  3 Percent  
Discount Rate  2.5 Percent  
Discount Rate  
2020  $12 $42 $62 
2025  $14 $46 $68 
2030  $16 $50 $73 
2035  $18 $55 $78 
2040  $21 $60 $84 
The SC -CO 2 is year specific; that is, environmental damages are estimated for a given 
year in the future and the value of the damages is discounted back to the present . The 
SC-CO 2 increases over time as systems become stressed from the aggregate impacts 
of climate change and future emissions cause incrementally larger damages. The 
SC-CO 2 is highly sensitive to the discount rate. The discount rate is the rate at which 
future benefits (or costs) are reduced such that they can be compared to a benefi t 
received in the present . In the context of the SC -CO 2, it is intended to represent the 
tradeoff for society between present and future welfare. Higher discount rates 
decrease the present value of future environmental benefits (avoided damages) . IWG 
estim ates the SC -CO 2 across a range of discount rates that encompass a variety of 
assumptions regarding the correlation between climate damages and consumption of 
goods and is consistent with OMB’s Circular A -4 guidance including the range of 
discounts. CARB ut ilizes the IWG standardized range of discount rates, from 2.5 to 
5 percent to represent varying valuation of future damages  (NASEM, 2017) . Because 
the IWG SC -CO 2 prices are in 2007 dollars, staff applied an inflation adjustment, using 
the California Consum er Product Index, to convert them into 2019 dollars, consistent 
with the rest of this analysis (California D epartment of F inance , 2020) .  
If all of the expected emission reductions projected under the Proposed Amendment s 
are achieved and assumed to be equivalent to CO 2 emission reductions, the avoided 
SC-CO 2 in a given year is the total emission reductions in metric tons of carbon 
dioxide equivalents (MT  CO 2e) multiplied by the SC -CO 2 (in $/ MTCO 2e) for that year. 
The annual emissions reductions from the Proposed Amendments and the estimated 
benefits are shown in Table IV- 10 below . The total benefits range between 
$339 million to $1. 43 billion through 2043, depending on the discount rate.   
81 Table IV-10. Avoided social cost of  carbon under  the Proposed Amendments  
(million 2019$) . 
Year GHG 
Emissions Reductions  
(MMT CO
2e) 5%  
Discount Rate  3%  
Discount Rate  2.5%  
Discount Rate  
2023  0.0 $0.0 $0.0 $0.0 
2024  0.0 $0.8 $2.7 $4.0 
2025  0.1 $2.4 $7.9 $11.7  
2026  0.2 $4.1 $13.7  $20.1  
2027  0.3 $6.0 $19.3  $28.2  
2028  0.4 $7.6 $25.0  $36.2  
2029  0.5 $9.4 $30.7  $45.0  
2030  0.6 $11.8  $36.7  $53.6  
2031  0.6 $13.3  $42.3  $61.4  
2032  0.7 $15.6  $47.6  $68.6  
2033  0.8 $16.8  $52.5  $75.3  
2034  0.8 $19.0  $57.1  $81.4  
2035  0.9 $20.1  $61.4  $87.1  
2036  0.9 $22.2  $65.4  $92.3  
2037  0.9 $23.1  $69.2  $98.3  
2038  1.0 $25.0  $72.6  $102.7  
2039  1.0 $25.7  $75.8  $106.7  
2040  1.0 $27.6  $78.8  $110.3  
2041  1.0 $28.1  $81.5  $113.6  
2042  1.1 $29.9  $82.8  $116.7  
2043  1.1 $30.2  $85.2  $119.6  
Total  13.9 $338.6  $1,008.3 $1,432.8 
There is an active discussion within government and academia about the role of 
SC-CO 2 in assessing regulations, quantifying avoided climate damages, and the values 
themselves. In January 2017, NASEM  released a report examining potential 
approaches for a comprehensive update to the SC -CO 2 methodology to ensure 
resulting cost estimates reflect the best -available science  (NASEM, 2017) . The NAS EM 
review did not modify the estimated values of the SC -CO 2, but evaluated the models, 
assumptions, handling of uncertainty, and discounting used in the estimati on of the 
SC-CO 2. The report titled, “Valuing Climate Damages: Updating Estimation of the  
82 Social Cost of Carbon Dioxide,” recommends near -term improvements to the existing 
IWG SC -CO 2 as well as long -term comprehensive updates (NASEM, 2017) . CARB  will 
continue to follow updates to the IWG SC -CO 2, outlined in the NASEM  report, and 
incorporate appropriate peer- reviewed modifications to estimates based on the lat est 
available data and science.  
It is important to note that the SC -CO 2, while intended to be a comprehensive 
estimate of the damages caused by carbon globally, does not represent the 
cumulative cost of climate change and air pollution to society. There ar e additional 
costs to society outside of the SC -CO 2, including costs associated with changes in co -
pollutants, the social cost of other GHGs including methane and nitrous oxide, and 
costs that cannot be included due to modeling and data limitations . The 
Intergovernmental Panel on Climate Change ( IPCC) has stated that the IWG SC -CO 2 
estimates are likely underestimated due to the omission of significant impacts that 
cannot be accurately monetized, including important physical, ecological, and 
economic impacts  (IPCC, 2007). CARB will continue engaging with experts to evaluate 
the comprehensive California -specific impacts of climate change and air pollution .  
E. Other Benefits  
In addition to emission reductions, ZEE offer a number of other benefits to operato rs 
when compared to SORE  equipment.  Small off -road equipment creates noise while in 
operation. Th e University of Florida reports that leaf blowers, edgers, hedge trimmers, 
pressure washers, and riding mowers create sound above the threshold  of 85 decibels 
(dB) set by  the Occupational Health and Safety Administration (OSHA)  (University of 
Florida, 2021). OSHA requires employers to implement a hearing conservation 
program when employees may be exposed to noise above this threshold (OSHA , 
2021). According to O SHA, electric lawn mowers expose users to noise from 63 to 
85 dB, depending on the mower. SORE  lawn mowers expose users to 82 to 91 dB, 
depending on the lawn mower, with the vast majority over 85 dB (OSHA, 2018 ). 
Electric chainsaws expose users to 61 to 84 dB, while SORE chainsaws expose users to 
86 to 91 dB (OSHA, 2018) . Chronic occupational exposure to sounds over 80 d B has 
been show n to be correlated with an increased risk for hypertension (Bolm -Audroff et 
al., 2020) . 
Specifically related to gasoline -powered lawn and garden equipment, it has been 
shown that the noise exposure and associated health effects from these will be more pronounced in workers because they will be operating in close proximity to this 
equipment for a significant amount of time, such as an 8-hour work day (Tint et al., 
2012). These workers often lack resources to protect themselves from high noise levels 
such as using hearing protection devices (Tint et al., 2012; Kearney et al., 2017). While 
the people in the community will also be exposed to the noise from lawn equipment, they will be farther away from the source and their exposure will be intermittent (Tint et al., 2012). ZEE  are quieter, which reduces noise at the worksite as well as in the 
community where the equipment is operatin g (Duvauchelle, 2021) . Many local 
jurisdictions such as the City of Los Angeles (1986) , City of San Diego (1991) , City of 
Dana Point  (2020) , and Sacramento  County  (2020) , have noise ordinances that limit  
83 when small off -road equipment can be used.  By choosing ZEE , owners may have more 
flexible working hours with their equipment .  
Further more , SORE equipment are  known to emit CO, PM 2.5, and TACs (Baldauf et al., 
2006). TACs are compounds that may contribute to mortality or adverse human health 
effects. Some TACs known to be emitted by lawnmowers are formaldehyde and 
acetaldehyde (Bal dauf et al., 2006). Formaldehyde  is a probable human carcinogen 
and can have eye and lung impacts upon acute exposure (CARB and Office of 
Environmental Health Hazard Assessment, 1992). Acetaldehyde is also a probable human carcinogen and acute exposure may be related to reproductive and developmental effects ( CARB and Office of Environmental Health Hazard Assessment, 
1993) . By choosing  ZEE, users of these equipment types would  have less  expos ure to 
TACs.  CO poisoning deaths from inhalation of SORE equipment exhaust c ould also be 
prevented by an increased  adoption of ZEE . CO poisoning can occur when users 
follow manufacturers’ instructions.  CO poisoning can also  occur from improper use of 
SORE equipment , including using the equipment indoors.  The Consumer Product 
Safety Commission notes that from 2015  through 20 17 there were an average of  97 
CO poisoning deaths nationally from engine -driven tools  per year, includ ing some 
from preempt equipment. Eighty -five percent of these deaths were attributed to the 
use of a generator  (Hnatov, 20 20).  
V. Environmental  Analysis  
A. Introduction 
This chapter provides the basis for CARB’s determination that no subsequent or supplem ental environmental analysis is required for the Proposed Amendments.   
CARB’s regulatory program, which involves the adoption, approval, amendment, or 
repeal of emission standards, rules, regulations, or plans for the protection and 
enhancement of the State’s ambient air quality, has been certified by the California 
Secretary for Natural Resources under Public Resources Code section 21080.5 of the California Environmental Quality Act (CEQA) (14 CCR 15251(d)).  Public agencies with 
certified regulatory progra ms are exempt from certain CEQA requirements, including 
but not limited to, preparing environmental impact reports, negative declarations, and initial studies.  Instead, CARB, as a lead agency, prepares a substitute environmental 
document (referred to as an  “Environmental Analysis” or “EA”) as part of the Staff 
Report to comply with CEQA (17 CCR 60000 -60008).  This chapter constitutes that EA.  
CARB’s regulatory program provides that CARB prepare an addendum to a certified EA for a proposed project if CARB det ermines that the circumstances set forth in the 
CEQA Guidelines, T itle 14 of the California Code of Regulations, section 15164 
(hereafter, “Section 15164”) apply to the proposed project (17 CCR 60004(b)(1)(B)) . 
Section 15164 provides that a “lead agency  … shall prepare an addendum to a 
previously certified [EA] if some changes or additions are necessary [to make to the underlying EA] but none of the conditions described in [ Title 14 CCR] section 15162  
84 [hereafter, “Section 15162”] calling for preparation of a subsequent [EA] have 
occurred.”   
The Proposed Amendments are substantively similar to a regulatory concept measure previously included within the 2016 State SIP Strategy ( CARB, 2017 b) for SORE  
(hereafter, “SORE SIP Measures”).  In its approval of the 2016  State SIP Strategy, CARB 
certified an EA, entitled Final Environmental Analysis for the Revised Proposed 2016 
State Strategy for the State Implementation Plan, (CARB, 2017 b) or Final EA, that 
evaluated the impacts associated with the SORE  SIP M easures and  mitigated those 
impacts, to the extent feasible, evaluated overarching alternatives to the 2016 State 
SIP Strategy and adopted a statement of overriding circumstances for impacts deemed significant and unavoidable.  While the Proposed Amendments fill in mo re 
detail with respect to specifying the more stringent emission standards and eventual 
emission standards of zero, the additional detail does not change the potential 
compliance responses identified in the Final EA. Rather, the only change triggered by the Proposed Amendments that warrants an addendum to the Final EA is the need to 
add the Proposed Amendments ’ detail to the project description of the SORE SIP 
Measures. Therefore, and for additional reasons in the following paragraphs, since the 
Final EA ad equately evaluated impacts, mitigation and alternatives associated with the 
SORE SIP Measures and the Proposed Amendments are substantively similar to the 
SORE SIP Measures, the Proposed Amendments do not trigger the need to prepare a subsequent EA.  
Secti on B of this chapter  V discusses the Final EA and its conclusions with respect to 
the SORE SIP M easure s. Section C briefly summarizes the Proposed Amendments and 
how they fit within the SORE SIP Strategy measure.  
B. Prior Environmental Analysis  
In March 20 17, the Board adopted the 2016 State SIP Strategy.  Generally, t he 2016 
State SIP Strategy is designed to reduce emissions of ozone -forming pollutants and 
PM2.5 and describes the programmatic and regulatory mechanisms of the federal 
Clean Air Act requirements to meet federal air quality standards.  CARB’s 2016 State 
SIP Strategy describes 27 specific measures and CARB’s commitment to achieve the 
mobile source and consumer products emission reductions needed to meet  NAAQS . 
The SORE SIP M easures included in the 2016 State SIP Strategy would:  
• Establish more stringent engine performance standards for cleaner combustion 
technologies (Low -NO
x Engine Standard);  
• Ensure that emissions control systems remain durable over the lifetime of the vehicle (Lower In -Use Emission Performance Level);  
• Increase the penetration of near -zero- and zero- emission technology across a 
range of applications;  
• Expand the requirements for cleaner Low -Emission Diesel fuels;  
• Conduct pilot studies to demonstrate new technologies;   
85 • Incent ivize the turnover of equipment and fleets to the cleanest technologies;  
• Increase system efficiencies; and  
• Reduce emissions from consumer products.  
When CARB staff proposed the 2016 State SIP Strategy  for the Board ’s consideration 
in March 2017, it include d an EA prepared under CARB’s certified regulatory program, 
referred to here as the Final EA  (as mentioned in s ection A of this Chapter V ). The 
Final EA provided a programmatic analysis of the potentially significant adverse and 
beneficial environmental im pacts resulting from implementation of the 27  measures in 
the 2016 State SIP Strategy, and their associated reasonably foreseeable compliance 
responses.   
The Final EA was based on the reasonably foreseeable compliance responses of the regulated  entities th at would be affected, in some manner,  by the aforementioned SIP 
measures, including the SORE SIP Measures. The Final EA concluded that 
implementation of the SIP measures could result in long -term beneficial impacts to air 
quality, energy demand, and GHGs . It further concluded that the proposed measures 
would result in less- than-significant impacts to: energy demand, long -term hazards and 
hazardous materials, land use and planning, mineral resources, population and 
housing, public services, and recreational services.  
The Final EA also concluded that, taking the 27 proposed measures together,  there 
could be potentially significant and unavoidable adverse impacts to aesthetics, 
agriculture and forest resources, short -term air quality, biological resources, cult ural 
resources, geology and soils, short -term hazards and hazardous materials, hydrology 
and water quality, noise, transportation/traffic, and utilities and service systems.  
The Final EA identified no direct impacts from the 2016 State SIP Strategy measures. Rather, CARB identified indirect adverse impacts  because the impacts are associated 
with activities that may occur in response to implementing the measures identified in 
the 2016 State SIP Strategy, not from the act of preparing and adopting the regulation 
or from its direct implementation and enforcement by CARB and its staff. As such, the indirect adverse impacts may take place by regulated entities and other third parties 
to comply with the 2016 State SIP Strategy measures . While many of the id entified 
potentially significant adverse impacts could be reduced to a less- than-significant level 
by mitigation,  CARB  lacks legal authority to impose the mitigation measures 
associated with development activities because it has no land -use permitting auth ority 
over those activities.  (Cal. Const., Article XI, section 7 [“ A county or city may make and 
enforce within its limits all local, police, sanitary, and other ordinances and regulations 
not in conflict with general laws. ”]; California Building Industry Assn. v. City of San 
Jose (2015) 61 Cal.4
th 435, 455; Big Creek Lumber Co. v. County of Santa Cruz (2006) 
38 Cal.4th 1139, 1151- 1152; HSC sections 39000- 44474 [CARB’s statutory authority 
provides no authority to regulate local land use permitting].)  Rathe r, the authority to 
determine project- level impacts and require project- level mitigation lies with land use 
and/or  other  permitting agencies for individual projects, causing inherent uncertainty 
in the degree of mitigation that may ultimately be implemented to reduce the  
86 project’s potentially significant indirect impacts  on the environment . Consequently, 
acknowledging this inherent uncertainty, the Final EA took  the conservative approach 
in its post -mitigation significance conclusion s and disclosed that the  project may have 
potentially significant and unavoidable adverse impacts because CARB lacked the 
permitting authority to address those indirect impacts from development  activities 
associated with the compliance responses.  
Even if CARB had authority to mitigate impacts from the 2016 State SIP Strategy, the 
potential impacts from development  activities cannot be quantified in a manner to 
inform mitigation measures.  Generally, in its rulemaking and planning activities, CARB 
staff seeks input from stakeholders on the issue of what stakeholders may have to do 
to comply with a regulation or plan. Since there is a great variety of stakeholders subject to a regulation and stakeholders’ manufacturing and supply chains are so complex,  there is inherent uncertainty relative to the exact compliance activities that 
may occur in response to a CARB regulation. As a result, there is inherent uncertainty 
relative to the scope of potential development  activities that stakeholders may 
undertake to comply with a particular regulation; relative certain ty would likely occur 
after the adoption of the regulation and during compliance periods as stakeholders 
reevaluate their operations to work towards regulatory compliance. With that 
certainty, stakeholders would then pursue necessary land use approvals and address 
adverse impacts through the land use permitting process. As a result, when CARB staff prepares an EA for a regulation or a plan, the indirect adverse impacts from a regulation or plan, such as the 2016 State SIP Strategy, are so ill -defined and relatively 
speculative that it would be nearly impossible to adequately quantify the exact impacts from a regulation for purposes of establishing mitigation. Given this, while the Final EA indicate d that there may be potential adverse environmental impacts from 
the 27 measures in the 2016 State SIP Strategy as a whole , it concluded that these 
impacts are speculative and cannot be precisely quantified until the scope of the measures is defined by actual proposed regulations. Therefore, CARB’s efforts to 
mitigate for ill -defined, speculative impacts in the Final EA necessarily sought to 
address overarching themes of the impacts (i.e. , dust mitigation from construction 
activities or addressing potential cul tural resource issues), but found that it was 
speculative to nail down exact mitigation criteria for unquantified impacts -- essentially, 
lacking the ability to address the “rough proportionality” constitutional metric in a quantified manner, but rather doi ng so in a general manner since the impacts are also 
identified in a broad, general manner.
q 
Collectively, taking into account all components of the 2016 State SIP Strategy across 
all categories, the Final EA concluded that the potential adverse environmen tal 
impacts of the 2016 State SIP Strategy are outweighed by the substantial air quality 
                                            
q As required by the Takings Clause of the 5th Amendment of the U.S. Constitution and codified in the 
CEQA Guidelines as follows: “(4) Mitigation measures must be consistent with all applicable 
constitutional requirements, including the following: ...(B) The mitigation measure must be ‘roughly 
proportional’ to the impacts of the project. Dolan v. City of Tigard , 512 U.S. 374 (1994) ….” (Title 14 
CCR section 15126.4(a)(4)(B).)   
87 benefits that will result from its adoption and implementation.  At its hearing on 
March  23, 2017, the Board adopted Resolution 17- 7 certifying the Final EA, approving 
the written responses to comments on the Final EA, and adopting the findings and 
statement of overriding considerations.  A Notice of Decision was filed with the Office 
of the Secretary of the Natural Resources Agency for public inspection.  
As discussed bel ow, the Proposed Amendments, which  implement the SORE SIP 
Strategy measure , do not require CARB to prepare a Subsequent EA precisely 
because they  merely add to the project description of the SORE SIP Strategy M easure 
and effectively mirrors the scope and u nderlying themes of the SORE SIP Strategy as 
identified in the Final EA. Thus, the Proposed Amendments have the same compliance 
responses, requiring the same generalized impact analysis that CARB conducted in the 
Final EA for the SORE SIP Strategy Measure.   
The SORE SIP Strategy measure summary and the potential compliance responses for it are  included in the following excerpt from the Final EA  (CARB, 2017b). 
1. Small Off -Road Engines  
a. Measure Summary  
This measure would reduce emissions from SORE and increase the penetration of zero- emission technology.  SORE  that are subject to C ARB regulations are used in 
residential and professional  lawn and garden equipment, and other utility applications.  
CARB staff would promote increased use of ZEE, propose tighter exhaust and 
evaporative emission standards, and enhance enforcement of current emissions standards for SORE.  
High failure rates have been observed in evaporative emissions testing of SORE , 
preventing previously -claimed emission reductions from being realized. Exhaust and 
evaporative emissions from SORE would be reduced through enhanced enforcement of the current emission standards, development of tighter emission standards, and increased use of ZEE. Strategies would be developed for transitioning to 
zero-emission technologies, including an initial focus on incentives for use of ZEE , 
coupled with increasingly stringent emission standards for criteria pollutants and GHGs.  
b. Potential Compliance Responses  
Reasonably foreseeable compliance responses under this measure would include an 
increase in manufacturing, production and use of zero -emission technology in SORE . 
This could require the construction or modification of associated manufacturing facilities to increase the supply of zero -emission technology fo r SORE , including 
battery electric- powered equipment . Increased  demand for lithium batteries could 
increase production, along with associated increases in lithium mining and exports 
from source countries or other  states would be anticipated. Disposal of any portion of 
vehicles, including batteries, would be subject to, and be in compliance with existing 
laws and regulations governing solid waste, such as California’s Universal Waste Rule  
88 (Cal. Code Regs. , tit. 22 , Chapter 23). That is, disposal of used batt eries into landfills is 
prohibited; however, they  could be refurbished or re -used . To meet an increased 
demand of refurbishing or reusing batteries, new facilities, or modifications to existing 
facilities, are anticipated to accommodate battery recycling activities.  Equipment 
replacement  may result in recycling or selling old equipment.  
C. The Proposed Amendments  
The Proposed Amendments are di scussed in detail in Chapter s II and XI of this Staff 
Report.  They  include the following elements that implement th e SORE SIP Strategy 
measure:  
1. Exhaust Emissions:  
• Significantly more stringent HC and  NO x exhaust emission standards on existing 
certification cycles :  
o For all equipment, except generators, emission standards will be set to 
0.00 for MY 2024  and subsequent model years ; 
o For generators in MYs 2024 through 2027,  HC and NO x exhaust 
emissions standards will be decreased by 40- 90 percent, depending on 
engine displacement category, and set to 0.00 for  MY 2028  and 
subsequent model years; 
o Continued use of emission reduction credits from the averaging, banking 
and trading program until the credits expire, five years after they are 
generat ed. The maximum FEL s for engine families would be lowered to 
levels equivalent to the current HC + NO x exhaust emission standards.  
• Other amendments to the exhaust emission regulations include: sunsetting the 
voluntary “Blue Sky Standards” after MY  2023r, changes to compliance and 
production line testing procedures, addition of CO to the averaging, banking 
and trading program, and a ne w zero- emission generator credit program; 
• Longer  emission s durability periods for some engines in MY 2024  and 
subsequent model years. 
2. Evaporative Emissions:  
• More stringent evaporative  emission standards.  
o For all equipment, except generators, emission standards will be set to 0.00 for MY 2024  and subsequent model years; 
o For generators, hot soak plus d iurnal emission standards for  MYs 2024 
through 2027 will be approximately 50 percent lower than current diur nal 
emission standards based on certification levels of currently- certified 
                                            
r The Blue Sky Standards were developed to allow manufacturers to receive recognition for certifying to 
lower emission stan dards, but CARB has no record of anyone taking advantage of the program for 
engines, so the proposal includes CARB ending its application after MY 2023.   
89 engines in California and set to 0.00 for MY  2028 and subsequent model 
years; 
o Continued use of emission reduction credits from the averaging, banking 
and trading program until the credits expire, five years after they are generated ; 
• Addition of a zero- emission generator credit program, which will allow more 
flexibility in the regulation s and allow manufacturers who generate  credits to 
trade them to  other  manufacturers;  
• Sunsetting  the optional Blue Sky Standards after MY  2023 due to lack of use by 
manufacturers ; 
• Allowing alternative fuel equipment to qualify for evaporative emission credits;  
• Repeal  the variance provision, which allows manufacturers to certify without 
actually meeting all certification requirement s and is subject to its own CEQA 
review process ; 
• Requirement for fuel cap s and  tether s to prevent fuel spillage during refueling;  
• Minor administrative changes to test procedures, including a tilt test which is 
designed to ac count for  excess emissions that come from fuel leaks when 
equipment is turned on its side for cleaning , transport ation  or storage;  
3. Enhanced Enforcement:  
• Modification of the compliance testing procedures for enforcement purposes. These would  allow CARB t o test “one or more” engines for compliance 
purposes and remove the requirement  to test engines in groups of five.  
D. Comparison of the Proposed Amendment s to the SORE SIP Strategy  
While there is more detail added to the Proposed Amendments as compared t o 
the SORE SIP Strategy measure, the general scope of the Proposed Amendments contains the general scope identified in the SORE SIP Strategy measure described  
above in s ection B of this Chapter V . Specifically, the general scope of the SORE 
SIP Strategy includes: “ Exhaust and evaporative emissions from SORE would be 
reduced through enhanced enforcement of the current emission standards, adoption  of tighter exhaust and evaporative emission standards, and increased use 
of zero- emission equipment.” Steps identified in the SORE SIP Strategy, in the 
quoted language, below, are substantively similar to the Proposed Amendments, 
including the following substantive similarities:  
• SORE SIP Strategy: “Strategies will be developed for transitioning to 
zero- emissions technologies, including an initial focus on incentives for use of 
zero- emission equipment, coupled with increasingly stringent emission 
standards for criteria pollutants ...” 
o Proposed Amendments-  
90  Focus on transitioning sales of small off -road equipment from 
SORE equipment to ZEE ; 
• Addition of a zero- emission generator credit program; 
• Set emission standards to zero for MY 2024 and subsequent 
model years  for all equipment except generators;  
• Set more stringent emission standards for generators for 
MYs 2024 through  2027  and set emission standards to zero 
for MY 2028 and subsequent model years. 
• Allows for the use of credits until they expire, even after the 
emission standards are zero ; 
• Setting both exhaust and evaporative emission standards to  
zero will further enhance the focus on the credit incentive 
to encourage the use of ZEE. 
 Once credits have expired, only ZEE  would be produced for sale  
or lease for use or operation in California, which w ould achieve the 
SORE SIP Strategy goal of transitioning to zero -emissions 
technology.  
• SORE SIP Strategy: “E nhance enforcement of current emissions standards for 
SORE .” 
o Changing regulatory language for compliance testing to allow for broader compliance testing of SORE . This would  reduce the burden on 
CARB’s testing facilitie s and  enable better enforcement of CARB’s SORE 
regulation . 
Additional, administrative and miscellaneous  changes were added in the Proposed 
Amendments (fuel cap tether, tilt test) which are guided by the SORE SIP Strategy 
measure to reduce emissions from SORE.  
E. Analysis  
1. Legal  Standards 
When considering  modifications  to a CEQA project for which  a substitute  document  
equivalent  to an Environmental  Impact Report  (EIR) or negative  declaration  has 
previously  been  prepared,  CARB  looks  to Public Resources Code  (PRC)  section  21166 
and CEQA Guidelines  section  15162  for guidance on the requirements for subsequent  
or supplemental  environmental  review.  
CEQA Guidelines  section 15162 states:  
(a) When an EIR has been certified or a negative declaration adopted for a project, 
no subsequent EIR shall be prepared for that project unless the lead agency 
determines, on the basis of substantial evidence in the light of the whole record, one or more of the following:   
91 (1) Substantial changes are proposed in the project which will require maj or 
revisions of the previous EIR or negative declaration due to the involvement 
of new significant environmental effects or a substantial increase in the 
severity of previously identified significant effects;  
(2) Substantial changes occur with respect to the circumstances under which the project is undertaken which will require major revisions of the previous EIR 
or negative declaration due to the involvement of new significant 
environmental effects or a substantial increase in the severity of previously 
ident ified significant effects; or  
(3) New information of substantial importance, which was not known and could not have been known with the exercise of reasonable diligence at the time 
the previous EIR was certified as complete or the negative declaration was 
adopted, shows any of the following:  
(A) The project will have one or more significant effects not discussed in the previous EIR or negative declaration;  
(B) Significant effects previously examined will be substantially more severe than shown in the previous EIR;  
(C) Mitigation measures or alternatives previously found not to be feasible would in fact be feasible and would substantially reduce one 
or more significant effects of the project, but the project proponents 
decline to adopt the mitigation measure or alternative; or  
(D) Mitigation measures or alternatives which are considerably different from those analyzed in the previous EIR would substantially reduce 
one or more significant effects on the environment, but the project 
proponents decline to adopt the mitigation measure or alternative.  
If a subsequent or supplemental EIR or negative  declaration  is not required,  the lead 
agency  may document  its decision and supporting  evidence in an addendum  (Title 17 
CCR section  60004.4(a);  Title 14 CCR section  15164 (e)). The addendum  and lead 
agency’s  findings should  include a brief explanation, supported  by substantial  
evidence,  of the decision not to prepare  a subsequent  or supplemental  EIR or 
negative  declaration ( Title 14 CCR section 15164(e)).  An addendum need not be 
circulated for public review, but must be considered by the lead agency prior to 
making a decision on the project ( Title 14 CCR section 15164(c), (d)). 
2. Basis for Determination  
CARB staff has determined that the Proposed Amendments do not involve any 
changes that result in any new significant adverse environmental impacts or a substantial increase in the severity of the significant adverse impacts previously 
disclosed in the prior Final EA.  Further, there are no changes in circumstances or new 
information th at would otherwise warrant any subsequent or supplemental  
92 enviro nmental review.  The Final EA adequately addresses the implementation of the 
2016 State SIP  Strategy as modified by the Proposed Amendments  and no additional 
environmental analysis is required.  The basis for CARB staff’s determination that none 
of the conditions requiring further environmental review are triggered by the 
Proposed Amendments is based on the following analysis.  
(1) There are no substantial changes to the measures previously analyzed in the 
Environmental Analysis which require major revisions to the Environmental Analysis involving new significant environmental effects or a substantial increase in the severity of previously identified effects.  
While the Proposed Amendments add more detail to the SORE SIP Strategy measure, 
the changes are not substantial in such a manner that warrants revisions to the Final 
EA. As noted earlier, the SORE SIP Strategy measure and the Proposed Amendment s 
are nearly  identical in scope  and substance , in that they both provide the following: 
exhaust and evaporative emissions from SORE would be reduced through enhanced 
enforcement of the current emission standards, development of tighter emission standards, and increased use of ZEE . While the Proposed Amendments include the 
repeal of the variance provision, the variance provision is an optional procedure  within 
the SORE regulatory program and is subject to a public hearing process and its own 
CEQA review  if CARB receives a variance application ; therefore,  given its optional 
feature  and separate CEQA process during review of a variance application,  repealing 
this provision will not involve new significant environmental effects or a substantial 
increase in the severity of previously identified effects. 
Since both measures are nearly identical in scope and substance as explained above, 
effectively creating a similar project description for both, it is foreseeable that the 
compliance responses identified in the Final EA would be substantially similar to those that may result from implementation of the Proposed Amendments.  The Proposed 
Amendments’ changes to the SORE SIP Strategy measure, while adding detail, are not substantial changes such that it would alter the foreseeable compliance responses. Therefore, since t he Proposed Amendments would not alter the foreseeable 
compliance responses identified in the Final EA for the SORE SIP Strategy measure, 
which constitute the primary means to determine if the Proposed Amendment s may 
have an impact on the environment, then  it stands to reason that the nonsubstantial 
changes to the SORE SIP Strategy measures identified in the Proposed Amendment s 
would not involve new significant environmental effects or a substantial increase in the severity of the previously identified significant effects in the Final  EA.  
The Final EA evaluated the anticipated indirect significant environmental effects from 
the reasonably foreseeable compliance responses to all 27 measures in the 2016 State SIP Strategy planning document. The Final EA included the SORE SIP Strategy’s 
compliance response, identified above, in this impact analysis. As noted, the Final EA 
identified some potential significant and unavoidable impacts in certain resource areas. The Final EA’s impact analysis centered on the potential for certain development that may occur in response to adoption of the 2016 State SIP Strategy 
measures. Specifically, for the SORE SIP Strategy, compliance -response development  
93 that could potentially occur is related to battery development (lithium mi ning, new or 
expanded battery recycling/disposal facilities) and new or expanded facilities to 
accommodate new product lines. As explained above, the Final EA could not, 
however, predict with any accuracy the level of development and associated impacts that could occur when it adopts more stringent emission standards, creates incentives 
for adoption of zero- emission technology, eventual transition to ZEE  and enhanced 
enforcement. As a result, the Final EA took a very conservative approach even though it did  not have a clear picture of specific projects that could occur in response to the 
SORE SIP Strategy measure and other measures, and proposed broadly defined mitigation measures that lead agencies should adopt if the compliance response 
development becomes a reality. However, since CARB has no land use authority to 
require these measures, it found that the impacts from the 2016 State SIP Strategy 
measures were potentially significant and unavoidable, triggering the adoption of a statement of overriding considerations to approve the project.  
Likewise, notwithstanding the Proposed Amendments’ specificity in implementing the general scope of the SORE SIP Strategy measure, the additional specificity does not contribute to an additional understanding of the exact  nature, scope and detail of 
potential compliance response projects and, as a result, does not change the impact 
analysis of the Final EA. CEQA defines significant effect on the environmental as “a 
substantial, or potentially substantial, adverse change in the environment.” (PRC 
section 21068) . A “significant effect on the environment [must] be based on 
substantial evidence in light of the whole record.” (PRC section 21082.2(a) ). 
“Argument, speculation, unsubstantiated opinion or narrative, evidence which i s 
clearly inaccurate or erroneous, or evidence of social or economic impacts which do not contribute to, or are not caused by, physical impacts on the environment, is not substantial evidence. Substantial evidence shall include facts, reasonable assumptions 
predicated upon facts, and expert op inion supported by facts.” 
(PRC  section  21082.2(c) ).  
Based on the record of the Proposed Amendments, CARB finds that there is no 
substantial evidence to support a finding that the Proposed Amendment s will cause 
new effects on the environment or increase the severity of those effects previously identified in the Final EA because the Proposed Amendments have the same compliance responses as those that were analyzed in the Final EA, and thus the impact analysis is the sam e as the impact analysis that evaluated the impacts from the 
compliance response- related development already disclosed in the Final EA.  Notably, 
like the findings on air quality and GHG in the Final EA, there is also an air quality and GHG benefit from the  Proposed Amendments. As discussed in Chapters III and  IV, 
above , the Proposed Amendments will have significant NO
x, ROG , GHG  and TAC 
emission reductions. Additionally, s ince there is no substantial evidence that can 
precisely identify project- specific imp acts from potential compliance -response 
development projects  due to the unknown nature of these projects , the identified 
emissions benefits from the Proposed Amendments cannot be counterweighed , 
without speculation,  against any potential air quality impacts from these projects . 
Therefore, the Proposed Amendments, while adding new detail to the SORE SIP  
94 Strategy Measures, do not involve new significant environmental effects or a 
substantial increase in the severity of previously identified effects in the Final EA.   
 (2) There are no substantial changes with respect to the circumstances under 
which the Proposed Amendments are being undertaken which require major 
revisions to the previous Environmental Analysis involving new significant 
environmental effects  or a substantial increase in the severity of previously 
identified effects.  
There are no substantial changes to the environmental setting or circumstances in 
which the Proposed Amendments are being implemented compared to those 
analyzed in the Final EA of  the 2016 State SIP Strategy. As explained above, the 
Proposed Amendments do not substantially alter the types of compliance responses 
of the regulated entities or result in any changes that significantly affect the physical environment.  
(3) There is no new information of substantial importance, which was not known 
and could not have been known with the exercise of reasonable diligence at the time the previous Environmental Analysis was certified as complete, that changes the conclusions of the Environmental Analysis with regard to impacts, mitigation measures, or alternatives.  
No new information of substantial importance that changes the conclusions of the 
Final EA has become available to CARB staff since the Final EA was certified.  The 
information available at the time the Board certified the  Final EA included the 
proposed SORE regulation concepts in 2016 State SIP Strategy, which, as noted, are 
substantively similar to the Proposed Amendments; thus , the Proposed Amendments 
do not present new information  that was  not already known when the Board certified 
the Final EA . There is likewise no new information of substantial importance that 
would alter  the compliance responses identified in the Final EA  because, due to the 
Proposed Amendments’ substantive  similarity to the SORE regulation identified in the 
2016 State SIP Strategy, the compliance responses for the Proposed Amendments are 
the same as those in the Final EA . Therefore, there is no new information of substantial 
importance that changes the conclusions in the Final EA about the potential environmental impacts to any resource areas, mitigation measures for those impacts or alternatives.  
 In sum, no supplemental or subsequent EA  is required for the Proposed Amendments  
because, as described above, t he Proposed Amendments do not result in any new 
environmental impacts or in a substantial increase in severity to the impacts previously 
disclosed in the Final EA.  Further, there are no changes in circumstances or new 
information that would otherwise warra nt an additional environmental review.   
95 VI. Environmental  Justice  
State law defines environmental justice as the fair treatment and meaningful 
involvement of people of all races, cultures, incomes, and national origins, with respect to the development, adoption, implementation, and enforcement of environmental laws, regulations, and policies (Gov . Code, § 65040.12, subd.  (e)(1)). “’Environmental  
justice ’ includes, but is not limited to, all of the following: (A) The availability of a 
healthy e nvironment for all people . (B) The deterrence, reduction, and elimination of 
pollution burdens for populations and communities experiencing the adverse effects of that pollution, so that the effects of the pollution are not disproportionately borne 
by thos e populatio ns and communities. (C) Governmental entities engaging and 
providing technical assistance to populations and communities most impacted by 
pollution to promote their meaningful participation in all phases of the environmental and land use decision making pr ocess. (D) At a minimum, the meaningful 
consideration of recommendations from populations and communities most impacted by pollution into environmental and land use decisions.”  (Gov . Code, § 65040.12 , 
subd.  (e)(2)). The Board approved its Environmental Justice Policies and Actions 
(Policies) on December 13, 2001, to establish a framework for incorporating 
environmental justice into CARB's programs consistent with the directives of State law 
(CARB , 2001). These P olicies apply to all communities in California , but are intended 
to address the disproportionate environmental exposure burden borne by low -income 
communities and communities of color. Environmental justice is one of CARB’s core 
values and fundamental to achieving its mission.  
Beyond the Policies, California’s 2017 Climate Change Scoping Plan says, “ Equity 
considerations must likewise be part of the deliberate and thoughtful process in the design and implementation of all policies and measures …” It also states, “ CARB must 
ensure that its ongoing engag ement with environmental justice communities will 
continue beyond the development of the Scoping Plan and be included in all aspects of its various air pollution programs .” (CARB , 2017a ). Together, these documents 
demonstrate CARB’s commitment to environmental justice.  
The Proposed Amendments would reduce statewide SORE emissions of NO
x and ROG  
by about half in 2031, compared to the Baseline Scenario . Reducing NO x and ROG  
emissions is an integral part of California reaching its goal of attaining and maintaining 
national  and California ambient air quality standards  for ozone , which  are protective of  
the health and welfare of all California resident s. Consequently, all communities, 
including disadvantaged low- income  communities and communities of color, would 
benefit f rom the P roposed  Amendments.  Staff expect s emission benefits will be 
greatest in areas with the highest emissions, which are likely to include disadvantaged 
communities where equipment users may have the oldest and highest -emitting 
equipment . The Proposed Amendments would help improve the overall health of 
these communities through fewer instances of premature mortality, fewer hospital and 
ER visits, and fewer lost days of work . These health benefits would  result from reduced 
tropospheric ozone and PM production as  NO x and ROG  emissions decreased .  
96 Users of SORE equipment are exposed to CO, PM 2.5, TACs , and other pollutants when 
operating equipment (Baldauf et al., 2006). Frequent users of lawn and garden  
equipment, particularly landscaping professionals, would be exposed to these air 
contaminants less frequently by replacing their SORE equipment  with ZEE. Employees 
of landscap ing businesses typically have  lower income  than an average employee in 
California. T he U.S. Census Bureau estimates  the average an nual salary for a 
landscaping business  employee in California  is $38,318  (U.S. Census Bureau, 2021) . 
This is substantially lower than the median salary of $ 75,235  per year  for the overall 
California population  (U.S . Census Bureau , 2021). Further , 67 percent of landscap ing 
business employees in the CSUF survey were identified as being Hispanic or Latino 
(CSUF SSRC, 2019). These users are disproportionately exposed to  CO, PM 2.5, and 
TACs, as noted above. Replacing SORE equipment with ZEE will reduce these 
exposures and protect the health of users, while offering a potential for  cost-savings to 
businesses.  The Proposed Amendments are consistent with CARB’s environmental 
justic e policy of  reducing exposure to air pollutants and reducing adverse health 
impacts from TACs  in all California communities.  
Sole-proprietorships  and other small business landscapers may be significantly 
affected  by the direct economic impacts of the Proposed Amendments. Small business 
landscapers make up more than 99 percent of landscaping businesses in California  
(U.S. Census Bureau, 2021). U.S . Census Bureau  data indicate  that more than 95 
percent of landscaping businesses have fewer  than five employees and approximately 
85 percent  of landscaping businesses are sole proprietorships (U.S . Census Bureau, 
2021) . Consequently, the higher upfront costs of ZEE  and the batteries needed to 
power the ZEE for a full work  day may be a significan t expense for many landscaping 
businesses. Generally, professional landscapers use a variety of equipment such as 
chainsaws, lawnmowers, leaf  blowers, string trimmers, and hedge trimmers  to 
complete the  majority of their  work  (CSUF SSRC, 2019) . Purchasing all new ZEE in 
addition to the batteries may be burdensome. However, despite larger upfront costs, 
within the first  few years of owning ZEE , net cost savings are expected due to 
decreas ing fuel costs . Also, over time , additional savings are expected from decreased 
maintenance and repair costs because the businesses would  no longer have the cost s 
of routine engine maintenance and repairs . Staff expect s that a landscaping business 
would not  need to purchase a full suite of ZEE at once , thereby avoiding a sig nificant 
one-time cost to transition to ZEE. Rather, staff expect s landscaping businesses would  
replace their equipment with ZEE as it breaks  or is replaced for other reasons . The 
SRIA in Appendix  I of this Staff Report  includes additional discussion of po tential costs 
and savings for small landscaping business es. 
Staff conducted outreach to landscaping professionals through several landscaping 
expos around the state. At these expos, staff had an exhibit table with  representative 
ZEE and literature available  to increase awareness for ZEE . Staff took the opportunity 
to inform participants about the ZEE Roadshow  and the availability of loan s of ZEE 
through that program.  The literature  was made available in both English and Spanish  
to facili tate enhanced accessibility . More information on outreach to landscapers can 
be found in section X.E of this Staff R eport.   
97 Of the 59,342 licensed landscaping companies in California, 50,722 are sole 
proprietorships, meaning the owner is also the only employee. These sole 
proprietorships have an average revenue of $32,000 per year ( U.S. Census Bureau, 
2021). For these companies, the upfront cost of ZEE can be significant, but if they can 
take advantage of incentive programs, they can realize cost- savings.  
Several air districts, including  SCAQMD and SJVAPCD, have existing incentive 
programs for landscapers. These programs allow landscapers to trade in their existing SORE equipment and get a substantial rebate or discount on their purchase of ZEE (SCAQMD, 2021 ; SJVAPCD, 2021).  A full discussion of available incentive programs 
can be found in s ection I.E of this report.  
There is further need for incentives to accelerate  the adoption of  ZEE, particularly for 
professional users and small businesses. Incentives for purchase of ZEE  would help 
these users meet their operational needs.  These users typically operate their 
equipment more frequently and, therefore, need more batteries to power their 
equipment throughout a work day. Batteries account for most of the price d ifferential 
between SORE equipment and ZEE.  Incentives can also play a role in technology 
advancement for those equipment  types , such as generators, for which  additional 
challenges exist in adoption  of zero- emission technologies. This will help achieve the 
goal to transition to  100 percent zero -emission off-road vehicles and equipment by 
2035 where feasible, as set out in EO  N-79-20 (California Executive  Order No. 
N-79-20. September , 2020). 
VII. Standar dized Regulatory Impact Analysis  
Sections 11346.3 and 11346.5 of the Government Code require State agencies to 
assess the potential for adverse economic impacts on California business enterprises and individuals when proposing to adopt or amend any administrative regulation. The 
assessment includes consideration of the impact of the Proposed Amendments on 
California jobs, business expansion, elimination, or creation, and the ability of California businesses to compete. State agencies are also required to estimate the cost or savings to any State or local agency or school districts in accordance with 
instructions adopted by the California Department of Finance (DOF). This estimate is to include any nondiscretionary costs or savings imposed on local agencies and the costs or savings in federal funding to the State.  
Government Code section 11346.3, subsection (c) requires a state agency to perform 
a SRIA before adopting any major regulation. Government Code section 11342.548 
defines a “major regulation” as “any proposed adoption, amendment, or  repeal of a 
regulation subject to review by the Office of Administrative Law  (OAL)  pursuant to 
Article  6 … that will have an economic impact on California business enterprises and 
individuals in an amount exceeding fifty million dollars ($50,000,000), as estimated by the agency.” Because the estimated economic impact of the Proposed Amendments on California business enterprises and individuals exceeds $50 million in at least one  
98 year during the implementation, the Proposed Amendments constitute a major 
regulation and requires CARB to prepare a SRIA.  
This chapter summarizes results that estimate the economic impacts of the Proposed Amendments. Overall, staff expects the Proposed Amendments would have a  net 
direct cost of $ 4.08 billion accrued  over the regul atory horizon . When all benefits are 
considered, the Proposed Amendments would have a cumulative net benefit of $4. 27 
billion and a benefit -cost ratio of 1. 30 over the regulatory horizon  of 2023 through 
2043. Resident ial users of small off -road equipment  are expected to experience a net 
direct cost accrued  through 2043 of $2. 79 billion, and professional users are expected 
to experience a n accrued  net direct cost of $1. 29 billion. T his difference is due to the 
difference in annual equipment use times between residential and professional users.  
Macroeconomic modeling shows a small impact on economic indicators such as gross State product, employment, output, and the personal income of individuals in California, as described in detail in this chapter. Thus, thi s regulatory action would  not 
have a significant adverse economic impact on businesses in California. Details on the calculations and assumptions used to perform this analysis are included in the SRIA, which is in Appendix I of this Staff Report and available on DOF’s website.
s   
A. Changes Since Original ly-submitted  SRIA 
On September 9, 2020, DOF  published the SRIA  for an earlier draft of the Proposed 
Amendments along with its  comments on the document to its  website. Since then, 
staff has updated the Proposed Amendments and the SRIA. An updated version of the 
SRIA can be found on DOF’s website and in Appendix I of  this Staff Report. This 
section  summarizes  the changes in the economic impact analysis that are incorporated  
in the updated SRIA  as well  as a summary of responses to DOF’s comments on the 
original SRIA.  
1. Response to DOF Comments  
DOF generally agreed with the methods and analysis included in the SRIA. The updated SRIA addresses the comments made by DOF staff. Specifically, the following changes were made:  
In response to DOF’s request that annual benefits such as avoided health costs and emission reductions be added, staff has added tables delineating the annual reduction in emissions, reduction in negative health outcomes, and associated benefits for both the Proposed Amendments and considered alternatives.  
In response to DOF’s comment that the SRIA should include a cost and benefit breakdown analysis for each of the nine regulated product categories identified by CARB to identify impacts on representative individuals and businesses that use the equipment , staff has added more discussion of specific equipment types. The reasons 
for and impacts of the largest upfront costs of adopting zero -emission generators and 
                                            
s https://www.dof.ca.gov/Forecasting/Economics/Major_Regulations/Major_Regulations_Table/   
99 pressure washers are now discussed. Further more , staff has added a table that shows 
the length of time it would take a  typical  owner of a piece of ZEE to experience 
cost-savings compared to SORE for each equipment type. This table shows that 
owners of some equipment types are expected to break  even nearly immediately, and 
owners of other equipment types may not break  even within the median  age of the 
equipment. Finally, staff has added more discussion of the differential impacts on 
residential versus professional users.  
2. Summary of  Updated Economic Analysis  
a. Direct Costs  
The Proposed Amendments are estimated to lead to an average annual net direct cost of $194.14  million dollars  and a  net direct cost of  $4.08 b illion accrued  over the 
regulatory horizon . Table VII -1 shows the total  annual  direct costs and cost -savings 
associated with the Proposed Amendments.  The Proposed Amendments would  yield 
annual net cost-savings starting in the year 2037 when the savings in fuel purchases 
and maintenance costs become greater than the increased cost of ZEE.  Figure VII -1 
shows the annual costs, cost -savings and net costs graphically.  
Tables VII -2 and VI I-3 show the total annual  direct costs and cost -savings for 
professional users ( nonlandscaping businesses, landscapers , and government entities) 
and residential users , respectively. Over the regulatory horizon , professional users 
would have a n accrued  net direct cost of $1.29 billion, and residential users would 
have a n accrued  net cost of $2.79 billion. This difference is due to the use time of the 
equipment by professional users. Residential users use their equipment less and keep their equipment longer than professional users, allowing for less turnover to ZEE and 
savings from reduced fuel and maintenance costs. While, overall , the Proposed 
Amendments would result in annual net  cost-saving s starting in 2037, professional 
users would experience annual  net cost-savings starting in 2034, and residential users 
starting  in 2041 . 
100 Table VII -1. Modeled costs to professional and residential users per year under  the 
Proposed Amendments relative to the B aseline Scenario  (million 
2019$) .  
(Negative values indicate cost -savings. Totals may differ slightly due to 
rounding.)  
Year Gasoline 
equipment 
cost Electric 
equipment 
cost Gasoline 
equipment 
maintenance cost Gasoline 
cost Electricity cost Total cost  Total cost -
savings  Net cost  
2023   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2024  -$91.75  $856.21  -$11.81  -$19.63  $3.91  $860.12  -$123.19   $736.93  
2025  -$88.62  $854.03  -$34.31  -$56.55  $10.67  $864.70  -$179.48   $685.22  
2026  -$85.44  $853.02  -$58.40  -$96.07  $18.21  $871.23  -$239.91   $631.32  
2027  -$82.22  $852.02  -$81.61  -$136.00  $25.81  $877.83  -$299.83   $578.00  
2028  -$822.59  $1,504.07  -$103.16  -$178.44  $34.08  $1,538.15  -$1,104.19   $433.96  
2029  -$828.20  $1,508.69  -$123.71  -$240.75  $44.62  $1,553.31  -$1,192.66   $360.65  
2030  -$833.89  $1,514.50  -$142.14  -$301.28  $55.77  $1,570.27  -$1,277.31   $292.96  
2031  -$839.63  $1,524.99  -$157.93  -$359.08  $65.33  $1,590.32  -$1,356.64   $233.68  
2032  -$845.44  $1,535.61  -$171.68  -$412.74  $74.14  $1,609.75  -$1,429.86   $179.89  
2033  -$851.31  $1,546.34  -$183.50  -$461.82  $82.04  $1,628.38  -$1,496.63   $131.75  
2034  -$857.25  $1,557.19  -$193.72  -$506.52  $89.10  $1,646.29  -$1,557.49   $88.80  
2035  -$863.25  $1,568.16  -$202.30  -$546.21  $95.29  $1,663.45  -$1,611.76   $51.69  
2036  -$869.32  $1,579.26  -$209.44  -$580.37  $100.52  $1,679.78  -$1,659.13   $20.65  
2037  -$875.46  $1,590.47  -$215.32  -$609.94  $104.98  $1,695.45  -$1,700.72  -$5.27  
2038  -$881.67  $1,601.81  -$219.92  -$635.31  $108.76  $1,710.57  -$1,736.90  -$26.33  
2039  -$887.95  $1,613.28  -$223.73  -$656.75  $111.92  $1,725.20  -$1,768.43  -$43.23  
2040  -$894.30  $1,624.88  -$226.59  -$674.35  $114.50  $1,739.38  -$1,795.24  -$55.86  
2041  -$900.72  $1,636.60  -$228.95  -$689.23  $116.67  $1,753.27  -$1,818.90  -$65.63  
2042  -$907.21  $1,648.46  -$230.99  -$702.09  $118.54  $1,767.00  -$1,840.29  -$73.29  
2043  -$913.77  $1,660.44  -$232.76  -$713.09  $120.14  $1,780.58  -$1,859.62  -$79.04  
Average  -$677.14  $1,363.33  -$154.86  -$408.39  $71.19  $1,434.53  -$1,240.39  $194.14  
Total -$14,219.99  $28,630.03  -$3,251.97  -$8,576.22  $1,495.00  $30,125.03  -$26,048.18  $4,076.85   
101  
Figure VII -1. Statewide Costs, cost -savings, and overall net costs under  the 
Proposed Amendments . 
(Negative values indicate cost -savings.)
 
102 Table VII -2. Modeled costs to professional users ( nonlandscaping businesses, 
landscapers and government entities) per year under  the Proposed 
Amendments relative to the B aseline Scenario  (million 2019$ ).  
(Negative values indicate cost -savings. Totals may differ slightly due to 
rounding.)  
Year Gasoline 
equipment 
cost Electric 
equipment 
cost Gasoline 
equipment 
maintenance cost Gasoline 
costs  Electricity costs  Total costs  Total cost-
savings  Net costs  
2023   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00  $0.00   $0.00  
2024   $46.63  $356.17  -$5.84  -$11.14  $2.80  $405.60  -$16.98   $388.62  
2025   $48.39  $355.70  -$17.42  -$34.00  $7.70  $411.79  -$51.42   $360.37  
2026   $50.16  $355.66  -$29.74  -$58.15  $13.20  $419.02  -$87.89   $331.13  
2027   $51.97  $355.61  -$41.53  -$82.24  $18.73  $426.31  -$123.77   $302.54  
2028  -$288.10  $549.81  -$52.27  -$105.21  $24.34  $574.15  -$445.58   $128.57  
2029  -$290.35  $551.34  -$62.09  -$133.13  $30.22  $581.56  -$485.57   $95.99  
2030  -$292.64  $553.30  -$70.64  -$157.63  $36.02  $589.32  -$520.91   $68.41  
2031  -$294.94  $556.94  -$77.76  -$180.21  $40.77  $597.71  -$552.91   $44.80  
2032  -$297.27  $560.63  -$83.81  -$200.31  $44.99  $605.62  -$581.39   $24.23  
2033  -$299.63  $564.35  -$88.90  -$218.08  $48.61  $612.96  -$606.61   $6.35  
2034  -$302.02  $568.11  -$93.21  -$233.83  $51.72  $619.83  -$629.06  -$9.23  
2035  -$304.43  $571.92  -$96.76  -$247.46  $54.35  $626.27  -$648.65  -$22.38  
2036  -$306.87  $575.76  -$99.67  -$258.97  $56.50  $632.26  -$665.51  -$33.25  
2037  -$309.34  $579.64  -$101.99  -$268.74  $58.27  $637.91  -$680.07  -$42.16  
2038  -$311.84  $583.56  -$103.74  -$276.85  $59.72  $643.28  -$692.43  -$49.15  
2039  -$314.36  $587.52  -$105.15  -$283.62  $60.91  $648.43  -$703.13  -$54.70  
2040  -$316.92  $591.52  -$106.16  -$289.07  $61.87  $653.39  -$712.15  -$58.76  
2041  -$319.50  $595.56  -$106.97  -$293.64  $62.68  $658.24  -$720.11  -$61.87  
2042  -$322.11  $599.65  -$107.64  -$297.58  $63.38  $663.03  -$727.33  -$64.30  
2043  -$324.75  $603.78  -$108.21  -$300.96  $63.98  $667.76  -$733.92  -$66.16  
Average  -$223.71  $505.55  -$74.26  -$187.18  $40.99  $555.93  -$494.54   $61.38  
Total -$4,697.92  $10,616.53  -$1,559.50  -$3,930.82  $860.76  $11,674.44  -$10,385.39   $1,289.05   
103 Table VII -3. Modeled costs to residential users per year under  the Proposed 
Amendments relative to the B aseline Scenario  (million 2019 $).  
(Negative values indicate cost -savings. Totals  may differ slightly due to 
rounding.)  
Year Gasoline 
equipment cost Electric equipment cost Gasoline equipment maintenance cost Gasoline costs  Electricity costs  Total costs  Total cost -
savings  Net costs  
2023   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00  $0.00  $0.00  
2024  -$138.38  $500.04  -$5.97  -$8.49  $1.11  $501.15  -$152.84  $348.31  
2025  -$137.01  $498.34  -$16.89  -$22.56  $2.97  $501.31  -$176.46  $324.85  
2026  -$135.61  $497.37  -$28.66  -$37.92  $5.01  $502.38  -$202.19  $300.19  
2027  -$134.19  $496.41  -$40.08  -$53.76  $7.08  $503.49  -$228.03  $275.46  
2028  -$534.49  $954.26  -$50.89  -$73.23  $9.74  $964.00  -$658.61  $305.39  
2029  -$537.85  $957.35  -$61.62  -$107.63  $14.40  $971.75  -$707.10  $264.65  
2030  -$541.25  $961.20  -$71.50  -$143.65  $19.76  $980.96  -$756.40  $224.56  
2031  -$544.69  $968.05  -$80.17  -$178.87  $24.57  $992.62  -$803.73  $188.89  
2032  -$548.16  $974.98  -$87.86  -$212.43  $29.15  $1,004.13  -$848.45  $155.68  
2033  -$551.68  $981.99  -$94.60  -$243.74  $33.43  $1,015.42  -$890.02  $125.40  
2034  -$555.23  $989.08  -$100.51  -$272.68  $37.38  $1,026.46  -$928.42  $98.04  
2035  -$558.82  $996.25  -$105.54  -$298.75  $40.94  $1,037.19  -$963.11  $74.08  
2036  -$562.45  $1,003.50  -$109.79  -$321.40  $44.02  $1,047.52  -$993.64  $53.88  
2037  -$566.12  $1,010.84  -$113.33  -$341.20  $46.70  $1,057.54  -$1,020.65  $36.89  
2038  -$569.83  $1,018.26  -$116.19  -$358.45  $49.03  $1,067.29  -$1,044.47  $22.82  
2039  -$573.59  $1,025.76  -$118.57  -$373.13  $51.01  $1,076.77  -$1,065.29  $11.48  
2040  -$577.38  $1,033.36  -$120.43  -$385.28  $52.63  $1,085.99  -$1,083.09  $2.90  
2041  -$581.22  $1,041.04  -$121.99  -$395.59  $53.99  $1,095.03  -$1,098.80  -$3.77  
2042  -$585.09  $1,048.81  -$123.34  -$404.51  $55.16  $1,103.97  -$1,112.94  -$8.97  
2043  -$589.02  $1,056.66  -$124.54  -$412.12  $56.16  $1,112.82  -$1,125.68  -$12.86  
Average  -$453.43  $857.79  -$80.59  -$221.21  $30.20  $887.99  -$755.23  $132.76  
Total -$9,522.06  $18,013.55  -$1,692.47  -$4,645.39  $634.24  $18,647.79  -$15,859.92  $2,787.87   
104 b. Costs to Professional Users  
Table VII -4 shows the upfront and ongoing costs along with the break -even point for 
professional users opting for ZEE over SORE  at 2023 prices. The prices and 
assumptions used in the ca lculation of costs can be fou nd in the SRIA in Appendix I. 
For most small off -road equipment categories, professional users ( nonlandscaping 
businesses, landscapers, and government entities) can experience cost-savings from 
purchasing ZEE instead of SORE eq uipment within five years  of purchasing the 
equipment. ZEE batteries can outlive the equipment for which they are purchased. By 
keeping the batteries from the previous equipment, a second purchase of a piece of ZEE would cost less. A professional user woul d reach cost- savings sooner  in such a 
scenario . 
Table VII -4. Upfront and annual ongoing costs for professional-grade SORE and 
ZEE, at 2023 prices . 
(Negative values indicate cost -savings.)  
Type of equipment 
 SORE upfront cost 
 ZEE upfront cost 
 SORE annual ongoing cost 
 ZEE annual ongoing cost
 Number of years of ownership before cost-savings 
with ZEE
 
Chainsaw  $390.55  $689.69  $139.47  $13.56  2 
Generator Set  $5,304.57  $6,818.88  $347.61  $34.79  5 
Lawn Mower  $1,409.42  $1,016.46  $220.13  $45.41  1 
Leaf Blower / 
Vacuum  $477.39  $1,723.11  $358.81  $22.80  4 
Corded Pressure 
Washer  $1,170.82  $3,036.92  $95.81  $91.11  N/At 
Pump < 2 hp  $454.62  $589.76  $98.69  $5.30  1 
Riding Mower  $11,337.17  $20,879.35  $952.17  $135.46  12 
Snow blower  $1,626.42  $1,431.81  $40.30  $7.89  1 
Trimmer/Edger/ Brush Cutter  $368.85  $860.11  $177.68  $14.21  3 
There are two notable exceptions to professional users  achieving cost -savings within 
five years . First, a typical  professional corded ZEE pressure washer owner would not 
break  even within the unit’s lifetime solely as a result of ongoing cost -savings. The 
                                            
t A typical professional user may not see cost -savings within the lifetime of a professional -grade corded 
or cordless pressure washer.   
105 same is true of a cordless unit which has an even higher upfront cost. As described in 
section C.1.c.v of the SRIA in Appendix I the average frequency of use of a 
professional -grade pressure washer is less than once per week, which would lead to 
minimal opportunities for savings through operational cost -savings. It is likely that the 
price of professional -grade ZEE pressure washers would decrease as a result of the 
Proposed Ame ndments, due to more manufacturers entering the ZEE pressure washer 
market. It is likely that a typical  professional user of a pressure washer would have a 
more economically favorable outcome if they were to rent a pressure washer when 
needed as opposed to  purchasing one. Furthermore, staff assume s that owners of 
professional -grade cordless pressure washers use their equipment at the average 
professional rate. It is likely that a professional user  that requires a cordless 
professional -grade pressure washer uses it more frequently than once a week, and will 
likely see savings much sooner than a typical  user.  
Second,  the break -even  point  for professional  ZEE riding mowers  would  be 12 years,  
which  is longer  than the five-year median  age in the CSUF  survey.  It is likely that more  
manufacturers  may enter  the market due to the Proposed  Amendments,  thereby 
driving  down  the upfront  cost.   
The SRIA describes the potential for typical and small businesses, including 
landscapers, to realize overall cost -savings due to the Proposed Amendments. A 
sole-proprietorship landscaping business could realize a savings of over $2,600 after 
five years of ownership of a suite of zero -emission lawn and garden equipment as 
compared to SORE equipment , assuming all such equipment was purchased at once.  
In 2024, all professional users of small off -road equipment on a statewide level are 
expected to incur a $403 million increase in upfront costs (cost to purchase ZEE  and 
SORE  equipment)  under the Proposed Amendments (Table VII -2). This would account 
for 53  percent of the total statewide upfront costs in 2024 associated with buying new 
ZEE despite professional -grade equipment accounting for less than 10  percent of the 
total equipme nt population. This cost is due to the fact that the incremental cost for 
opting for professional -grade ZEE is higher than the incremental cost for residential -
grade ZEE. This upfront cost would increase each year until 2028, when it would 
decrease to $262 million. This decrease in cost is a result of the emission standard  
being zero for MY 2028 . The price of a MY  2024 compliant generator is nearly twice as 
much as the price for an equivalent professional -grade zero -emission generator 
estimated for this ana lysis. The  annual  net upfront cost would increase with each 
following year until 2043 when it would be $279 million.  
In 2024, professional users are predicted to have statewide savings of $14.18 million in ongoing operational costs for small off -road equipment as a result of avoided SORE 
maintenance and gasoline costs under the Proposed Amendments. Professional users would realize 45 percent of the total statewide ongoing operational cost -savings 
despite accounting for less than 10 percent of the total equipment population due to their higher usage of equipment. The savings in ongoing operational costs would 
increase each year through 2043 and reach a maximum of $345 million.   
106 Professional users would realize an overall statewide annual  net cost -savings under the 
Proposed Amendments starting in 2034 due to savings in ongoing operational costs 
(Table  VII-2). Many professional users, especially those who do not use generators or 
pressure washers, may realize net cost -savings within a few years of purchasing ZEE . It 
is unlikely that the typical small landscaping business has one of these items. It is 
possible that a small business landscaper could purchase a small residential -grade 
zero- emission generator to help charge spare batteries during the workday. Such a  
generator would cost significantly less than the professional -grade zero -emission 
generator included in this analysis.  
c. Costs to Residential Users  
Table VII -5 shows the upfront and ongoing costs along with the break -even point for 
residential  users optin g for ZEE over SORE . Residential users would see on average 
longer ownership times before they reach net cost- savings from lower ongoing costs 
to offset the increased upfront cost.  CSUF survey data showed that residential users 
often keep their small off -road equipment for more than  10 years. With  lifetimes that 
long, cost -savings from adopting ZEE can be realized for most equipment types.  
Table VII -5. Upfront and annual ongoing costs for  residential users of small 
off-road equipment . 
(Negative values indicate cost- savings.)  
Type of equipment SORE upfront cost  ZEE upfront cost  SORE annual ongoing cost  ZEE annual ongoing cost Number of years of ownership before cost-savings 
with ZEE 
Chainsaw  $156.24  $586.19  $30.97  $1.50  15 
Generator Set  $861.49  $2,138.69  $115.41  $13.95  13 
Lawn Mower  $303.79  $424.26  $13.39  $1.47  10 
Leaf Blower/ 
Vacuum  $161.67  $318.64  $23.83  $1.20  7 
Pressure Washer  $400.37  $349.05  $32.78  $3.04  1 
Pump < 2 hp  $243.15  $264.28  $6.10  $0.35  4 
Riding Mower  $2,633.60  $3,253.92  $136.52  $8.17  5 
Snow Blower  $432.72  $429.04  $0.77  $0.14  1 
Trimmer/Edger/  
Brush Cutter  $165.03  $213.85  $16.22  $1.29  3 
 
Two equipment types for which residential users may not realize cost -savings are 
chainsaws and generators.  SORE c hainsaws are small, currently inexpensive, and  
107 typically used infrequently by residents, making it unlikely that cost -savings would be 
realized by residential users purchasing zero- emission chainsaws. For the reasons 
discussed in section I.E.3.b , zero- emission generators currently often have a higher 
purchase price than SORE generators. While the cost to purchase  a zero- emission 
generator may decrease in the coming years, it will likely still be significantly higher 
than an equivalent SORE generator. While a 13- year period to break  even is beyond 
the median age for residential generators, many users keep their generators for at least 13 years. Of residential generator owners in the CSUF survey, 39 percent said their generator was at least 10  years o ld.  
In 2024, residential users of small off -road equipment on a statewide level would be 
expected to incur a $362 million increase in upfront cost under the Proposed 
Amendments (Table VII -3). This would account for 47 percent of the total statewide 
costs in 2024  associated with buying new equipment despite residential  equipment 
accounting for over 90 percent of the total population of equipment. This cost is due 
to the higher purchase price of residential -grade ZEE relative to SORE equipment. 
This upfront cost would increase slightly until 2028, when it would increase 
significantly to $420 million. This increase in cost is due to the generator emission standards being zero starting in MY 2028. The price of a MY  2024 residential -grade 
emission- compliant generator is lower than that of a zero -emission generator. The 
annual  net upfront cost would increase slightly with each following year through 2043, 
when it would be $468 million.  
In 2024, residential users are expected to have statewide savings of $13.35 million in 
ongoing operational costs for small off -road equipment as a result of avoided SORE 
maintenance and gasoline costs under the Proposed Amendments. The savings in ongoing operational costs would increase each year through 2043 and reach a maximum of $481 million. 
Residential users would realize an annual  statewide net cost -savings under the 
Proposed Amendments starting in 2041 due to savings in ongoing operational costs 
(Table  VII-3). This is seven years after professional users are expected to experience a 
statewide  annual  net cost -savings. This delay is due to the longer period residential 
users keep their equipment and the lower rate at which they use it. Residential users often keep their small off -road equipment for more than 10 years. CSUF survey  data 
show that they typically choo se not to replace it until it breaks. Therefore, even though 
ZEE is more prevalent in residential use today than in professional use, it will take 
much longer for many residential users to adopt ZEE.  
Statewide, over the  regulatory horizon  analyzed in the SRIA  attached as Appendix I , 
resident ial user s would  experience an accrued  net cost of $2.79 billion due to the 
Proposed Amendments. Per U.S. Census data, there are 13,072,122 occupied housing units in California  (U.S. Census Bureau, 2018 a). From CSUF survey data, only 44 
percent of California households own powered lawn and garden equipment, and 40 
percent own some other type of small off -road equipment. Assuming that 50 percent 
of the households in California own at least one piece of small off -road equipment, the 
net cost of the Proposed Amendments would amount to $21.34 per household per  
108 year over the period 2024 through 2043 . Per U.S. Census data, the median income of 
California ho useholds before taxes is $75,277  (U.S. Census Bureau, 2018a ). The 
incremental cost would therefore be less than 1/10th of one percent of their pre -tax 
income. This indicates that a demand response to the slightly increased prices under 
the Proposed Amendments would be minimal and is not expec ted to have a 
significant effect on the results presented in this section.  
d. Cost-Effectiveness  
The metric to quantify cost- effectiveness of the Proposed Amendments is the ratio of 
total monetized benefits divided by total monetized costs. A  comparison of  this type is 
an appropriate cost- effectiveness measure because the harm associated with 
increased emissions is captured in the estimates of monetized health impacts. A benefit -cost ratio greater than one implies that the benefits of the scenario are greater  
than its costs. Benefits include both health benefits and cost -savings after subtracting 
tax and fee revenue impacts to state and local governments. Table VII -6 indicates that 
the Proposed Amendments would have a cumulative net benefit of $4.27 billion and a 
benefit -cost ratio of 1. 30, meaning benefits would be  greater than costs during the 
regulatory horizon .  
Table VII -6. Cost-benefit analysis of the Proposed Amendments (billion 2019$) . 
Scenario  Total 
costs  Health benefits  Cost-
savings (benefit)  Tax & fee revenue  Total benefit  Net benefit  Benefit-cost ratio 
Proposed 
Amendments $14.41  $8.82  $10.33  -$0.47  $18.68  $4.27  1.30  
 
e. Emission Reduction Credit Sensitivity Analysis  
To demonstrate that differences in the total amount of banked emission reduction 
credits would  not significantly change the outcome of the economic analyses, a 
sensitivity analysis was performed. Two scenarios were modeled —one with no banked 
credits, and one with twice the amount of banked credits that manufacturers held at 
the end of MY 2018.  
For the scenario  with no banked credits, all new equipment purchased starting in 2024 
were  assumed to be compliant with the more stringent emission standards. In this 
scenario, the net direct cost would be $4.18 billion over the regulatory horizon , 
$104.26 million more than in the Proposed Amendments scenario.  
For the scenario  with twice the amount of banked credits that manufacturers held at 
the end of MY 2018, all banked credits were assumed to be fully used between MY s 
2024 and 2027 for generators. It was assumed that 12.6 percent of new generator sales would be generators with the same price as that of currently compliant 
generators . This would yield a net direct cost  of $3.97 billion over the regulatory 
horizon , $104.27 million less than in the Proposed Amendments scenario.   
109 B. Discussion of Macroeconomic Modeling Results  
This section describes the estimated total impact of the Proposed Amendments on the 
California ec onomy. The Proposed Amendments will result in incremental cost s and 
cost-savings for businesses to comply with the regulations . These costs result in direct 
changes in expenditures in the economy as these costs are passed on to professional 
and residential  users . These changes in expenditures by users will indirectly affect 
employment, output, and investment in sectors that supply goods and provide services to affected businesses. These direct and indirect effects lead to induced effects, such as changes in  personal income that affect consumer expenditures across 
other spending categories. The total economic impact is the sum of these effects and 
is presented in this section.  
1. Macroeconomic Model and Inputs  
The total economic impact of the Proposed Amendments is simulated relative to the 
Baseline Scenario using the cost estimates described in SRIA Chapter C. The analysis 
focuses on the changes in major macroeconomic indicators from 202 3 through 2043, 
includin g employment, output, personal income, and gross state product. The years of 
the analysis are used to simulate the Proposed Amendments through more than 12 months post full implementation.  
Regional Economic Models, Inc. (REMI) Policy Insight Plus  Version 2.4 is used to 
estimate the macroeconomic impacts of the Proposed Amendments on the California 
economy. REMI is a structural economic forecasting and policy analysis model that 
integrates input -output, computable general equilibrium, econometric a nd economic 
geography methodologies.
u  REMI Policy Insight Plus provides year -by-year estimates 
of the total economic impacts of the Proposed Amendments, pursuant to the 
requirements of SB 617 and the California Department of Finance.v CARB uses the 
REMI s ingle- region, 160- sector model. Several adjustments were made to the model 
reference case to reflect the impacts of COVID -19 and to reflect the Department of 
Finance conforming forecasts. First, the REMI model’s National Control was updated with a short -term national forecast based on the U.S. Economic Outlook for 2020- 2022 
from the University of Michigan’s Research Seminar in Quantitative Economics (RSQE)
w 
release on April 9, 2020, which was made available in the latest REMI model. Second, the National and  Regional Controls in REMI were updated to reflect the most recent 
Department of Finance conforming forecasts which include population projections 
dated January 2020 and U.S. real GDP forecasts, and California civilian employment 
growth numbers Dated May 2 020. Because the Department of Finance forecasts only 
                                            
u For further information and model documentation see: https://www.remi.com/model/pi/ .  
v Senate Bill 617 (Calderon, Stats. of 2011, Ch. 496; amending Gov. Code §§ 11346.2, 11346.3, 
11346.5, 11346.9, 11347.3, 1139.1, 13401, 13402, 13403, 13404, 13405, 13406, 13407 and adding Gov. 
Code §§  11342.548, 11346.36, 11349.1.5); Department of Finance Standardized Regulatory Impact 
Assessment For Major Regulations, Cal. Code Regs., tit. 1, §§ 2000 et seq.  
w This update assumes that the economic contraction is severe but that aggressive federal response to 
the pandemic maintains the possibility of a vigorous recovery: https://lsa.umich.edu/econ/rsqe.html .  
110 extended to 2023, CARB staff assumed that post -2023, U.S. income and employment 
would continue to grow at the same rate as projected in the RSQE forecast, while 
California civilian employment would continue to recover at the rate forecasted by the 
Department of Finance, until it returned to baseline levels.  
The results from the REMI model provide estimates of the impact of the Proposed Amendments on the California economy. The California economy is forec asted to 
grow post -2020. Therefore, negative impacts reported here should be interpreted as a 
slowing of growth and positive impacts as an acceleration of growth resulting from the Proposed Amendments. The results are reported in VII.B.2 in four -year intervals from 
2023 through 2043.  
2. Creation and Elimination of Jobs within the State of California  
Table VII -7 presents the impact of the Proposed Amendments on total employment in 
California across all private industries and the public sector. Employment comprises estimates of the number of jobs, full -time plus part- time, by place of work for all 
industries. Full -time and part- time jobs are counted at equal weight. Employees, sole 
proprietors, and active partners are included, but unpaid family workers and volunteers are not included. The employment impacts represent the net change in 
employment across the economy, which is composed of positive impacts for some 
industries and negative impacts for others. The Proposed Amendments are estimated 
to result in an initial decrease in employment growth that is less than 0.03 percent of 
baseline employment  that diminishes towards the end of the regulatory horizon.  
Table VII-7. California employment impacts under  the Proposed Amendments. 
 Metric  2023  2027  2031  2035  2039  2043  
California 
Employment  22,603,913  24,725,694  24,765,385  25,011,315  25,539,578  26,209,650  
% Change  0.00%  -0.02%  -0.01%  0.00%  0.00%  0.00%  
Change in Total Jobs  0 -4,908  -1,465  -836 -614 -453 
The total employment impacts presented above are net of changes at the industry 
level. Table VII -8 show s the changes in employment by industries that are directly 
impacted by the Proposed Amendments. As the requirements of the Proposed 
Amendments go into effect , the industries generally realizing reductions in production 
cost or increases in final demand see an increase in employment growth. There is 
initially a decrease in job growth that corresponds with the higher equipment  cost 
from the emission standards of zero  that is not immediately offset by fuel savings . 
Over time , as the  operational savings from  zero-emission equipment accrue,  
landscaping businesses begin to realize gasoline fuel cost -savings and other 
operational savings that more than offset the incremental equipment cost . These 
gasoline fuel savings result in lower production costs, diminishing t he negative initial 
impact on job growth over the regulatory period. The oil and gas extraction industry  
111 and personal and household goods repair and maintenance industry see a decreased 
employment growth rate due to a reduction in final demand for their go ods and 
services. The reduced fuel consumption also reduces tax revenues, resulting in lower state and local government spending and employment  as seen in Table VII -8. 
Table VII -8. Job impacts by primary and s econdary industries under  the Proposed 
Amendmen ts. 
Industry  Unit 2023  2027  2031  2035  2039  2043  
Electric power generation, 
distribution (2211)  % Change  0.00%  0.03%  0.11%  0.15%  0.17%  0.17%  
Electric power generation, distribution (2211)  Change in Jobs  0 12 41 58 64 65 
Petroleum and coal products manufacturing 
(324)  % Change  0.00%  -0.11%  -0.24%  -0.33%  -0.36%  -0.35%  
Petroleum and coal products manufacturing (324)  Change in Jobs  0 -15 -31 -40 -42 -40 
Agriculture, construction, and mining machinery manufacturing (3331)  % Change  0.00%  0.06%  0.08%  0.08%  0.08%  0.08%  
Agriculture, construction, and mining machinery manufacturing (3331)  Change in Jobs  0 2 3 3 3 3 
Retail trade (44- 45) % Change  0.00%  0.01%  0.02%  0.01%  0.01%  0.01%  
Retail trade (44- 45) Change in Jobs  0 134 372 302 262 248 
Services to buildings and dwellings (5617)  % Change  0.00%  -0.03%  0.00%  0.02%  0.02%  0.02%  
Services to buildings and dwellings (5617)  Change in Jobs  0 -92 12 64 90 100 
Personal and household goods repair and maintenance (8114)  % Change  0.00%  -1.65%  -3.13%  -3.97%  -4.31%  -4.40%  
Personal and household goods repair and maintenance (8114)  Change in Jobs  0 -325 -593 -723 -762 -757 
State & Local Government  % Change  0.00%  0.00%  -0.01%  -0.02%  -0.02%  -0.02%  
State & Local Government  Change in Jobs  0 -81 -246 -387 -462 -479 
3. Impacts on  Business Output within the State of California  
Gross output is used as a measure for business impacts because it represents an 
industry’s sales or receipts and tracks the quantity of goods or s ervices produced in a 
given  period. Output is the sum of the amount of production, including all  
112 intermediate goods purchased as well as value added (compensation and profit), 
across all private industries and the public sector. Output is affected by production 
cost and demand changes. As production cost increases or demand decreases, output 
is expected to contract. As production costs decline or demand increases, industry will likely experience output growth.  
The results of the assessment of impacts due to the Propo sed Amendments show a 
decrease in output of $772 million in 2027 and a decrease of $369 million in 2043 as shown in Table  VII-9, representing a change that does not exceed 0.01 percent of 
baseline output. The results for each impacted industry are also shown in Table VII -9. 
Similar to the employment impacts, there is an initial negative impact on the services 
sector that diminishes over time and negative impacts on  petroleum and coal products 
manufacturing, and on  personal and household goods repair and maintenance. The 
public sector also experiences negative impacts as seen in Table VII -9. The negative 
output impact on manufacturing is primarily driven by the petroleum and coal products manufacturing industry, which is estimated to see a sizeable decrease i n final 
demand for gasoline. 
113 Table VII -9. Change in California output growth by industry  under  the Proposed 
Amendments. 
Industry  Metric  2023  2027  2031  2035  2039  2043  
California Economy  Output 
(2019$M)x 4,848,370  5,519,530  5,804,974  6,209,827  6,785,735  7,466,638  
California Economy  % Change  0.00%  -0.01%  -0.01%  -0.01%  -0.01%  0.00%  
California Economy  Change 
(2019$M)  0 -772 -454 -398 -393 -369 
Electric power generation, transmission, and distribution (2211)  % Change  0.00%  0.03%  0.11%  0.15%  0.17%  0.17%  
Electric power generation, transmission, and distribution (2211)  Change (2019$M)   0 13 47 71 84 90 
Petroleum and coal products manufacturing (324)  % Change  0.00%  -0.11%  -0.24%  -0.33%  -0.36%  -0.36%  
Petroleum and coal products manufacturing (324)  Change (2019$M)  0 -116 -258 -369 -432 -460 
Agriculture, construction, and mining machinery manufacturing (3331)  % Change  0.00%  0.06%  0.08%  0.08%  0.08%  0.08%  
Agriculture, construction, and mining machinery manufacturing (3331)  Change (2019$M)  0 2 2 2 2 3 
Retail  trade (44- 45) % Change  0.00%  0.01%  0.02%  0.02%  0.01%  0.01%  
Retail trade (44- 45) Change (2019$M)  0 17 53 48 46 48 
Services to buildings and dwellings (5617)  % Change  0.00%  -0.03%  0.00%  0.02%  0.02%  0.03%  
Services to buildings and dwellings (5617)  Change (2019$M)  0 -7 1 5 8 10 
Personal and household goods repair and maintenance (8114)  % Change  0.00%  -1.65%  -3.15%  -4.01%  -4.36%  -4.45%  
Personal and household goods repair and maintenance (8114)  Change (2019$M)  0 -44 -81 -101 -110 -112 
State & Local Government  % Change  0.00%  0.00%  -0.01%  -0.02%  -0.02%  -0.02%  
State & Local Government  Change (2019$M)  0 -15 -47 -76 -94 -100 
                                            
x Millions of fixed 2019 dollars (2019M$)   
114 4. Creation and Elimination of Businesses within the State of California  
The REMI model cannot directly estimate the creation or elimination of businesses. 
Changes in jobs and output for the California economy can be used to understand 
some potential impacts. The overall jobs and output impacts of the Proposed Amendments are very small relative to the total California economy, representing changes less than 0.03 percent. However, impacts in some specific sectors are larger. 
The trend of decreasing production costs for the services to buildings and dwellings 
industry has the potential to result in an expansion or increase in the number of businesses in this industry if sustained over time. The decreasing trend in demand for gasoline following from the Proposed Amendments has the potential to result in a 
decrease in the number of businesses in this industry if sustained over time. The 
personal and household maintenance and repair industry sees the largest relative decrease in industry employment and output from the Proposed Amendments and may be indicative of potential business cont raction or eliminations. In particular, we 
expect small -engine repair shops to see significant impacts to their business. ZEE do  
not contain an engine and are  expected to need significantly less repair than SORE 
equipment . The remaining revenue for these businesses would likely come from repair 
of equipment other than SORE, such as saws and hand tools, from repair that would 
be conducted on both ZEE and SORE, including blade sharpening, as well as from 
sales of new equipment.  
5. Significant Statewide Adverse Economic Impact Directly Affecting Business  
The Executive Officer has made an initial determination that the proposed regulatory 
action  would not  have a significant statewide adverse economic impact directly 
affecting businesses, including the ability of  California businesses to compete with 
businesses in other states, or on representative private persons.   
6. Competitive Advantage or Disadvantage  
The small off -road equipment manufacturers that must comply with requirements of 
the Proposed Amendments are mostly based outside of California and therefore do 
not present any competitiveness impacts for this industry inside California. Small 
off-road equipment dealers may potentially find themselves at a competitive 
disadvantage as a result of the Proposed Amendments. Businesses, or individuals 
could purchase small off -road equipment out of state and bring it into California for 
use. Due to the small price differences on the household side of the market between 
SORE equipment and ZEE, this is unlikely to happen at the individual level. However, 
the high er upfront costs associated with professional ZEE may make this enticing for 
large businesses. The additional costs of transportation for purchasing and repair may prevent some of this. In contrast, online sales of noncompliant equipment are 
expected to be low, as CARB staff search es for such equipment and has initiated 
enforcement mechanisms against online retailers selling noncompliant SORE. The requirements result in an incremental net savings to professional users of the 
equipment. These net savings are anticipated to be realized generally across 
professional users and are not anticipated to result in any competitive advantages or disadvantages within industries.   
115 7. Impacts on Investments in California  
Private  domestic investment consists of purchases of residential and nonresidential 
structures and of equipment and software by private businesses and nonprofit 
institutions. It is used as a proxy for impacts on investments in California because it provides an indicator of the future productive capacity of the economy.  
The relative changes to growth in private investment for the Proposed Amendments 
are shown in Table VII -10 and show a decrease of private investment by about $231 
million in 2027 and an increase of $41 million in 2043, not exceeding 0.05 percent of 
baseline investment.  
Table VII -10. Change in gross domestic private investment growth under  the 
Proposed Amendments . 
Metric  2023  2027  2031  2035  2039  2043  
Private Investment 
(million 2019$)  360,677  465,577  489,344  525,926  578,181  636,163  
% Change  0.00%  -0.05%  0.00%  0.01%  0.01%  0.01%  
Change 
(million 2019$)  0 -231 13 48 43 41 
8. Incentives for Innovation  
The Proposed Amendments to the SORE regulations are written to give maximum 
flexibility to manufacturers, while still meeting California’s air quality goals. A new  
zero- emission generator  credit program is being added to incentivize an earlier 
adoption of  zero- emission generators by allowing credit ge neration to offset emission s 
from SORE . 
9. Benefits of the Regulation  
Benefits of the Proposed Amendments to public health, worker safety, and the state’s environment are described in detail in Chapter IV. Public health benefits when 
monetized yield a cos t-savings of $8.82 billion. 
VIII. Evaluation  of Regulatory Alternatives  
Government Code section 11346.2, subdivision (b)(4) requires CARB to consider and 
evaluate reasonable alternatives as compared  to the selected alternative, the 
Proposed Amendments,  and provide reasons for rejecting those alternatives. This 
section discusses the alternatives to the Proposed Amendments that CARB evaluated 
and provides the reasons why these alternatives were not ultimately selected or 
included in the Proposed Amendments .   
116 During the development process of the Proposed Amendments, CARB staff solicited 
public input regarding alternatives that would achieve the Proposed Amendments’ 
goals . Staff evaluated several alternatives to the proposal, including suggestions from 
both public and industry stakeholders. CARB staff discussed these potential 
alternatives with stakeholders. Staff has chosen three alternatives to the Proposed 
Amendment s for formal evaluation. T he evaluation of alternatives considered  includes 
an analysis of c ost impacts and health benefits of each alternative using the same 
modeling methods as identified above for the Proposed Amendments and a 
discussion o f reasons for rejection . As explained below, no alternative proposal  was 
found to be less burdensome and equally effective in achieving the purposes of the 
Proposed Amendments in a manner that ensures full compliance with the authorizing 
law being implemented or made specific by the Proposed Amendments. The Board 
has not identified any reasonable alternatives that would lessen any adverse impact on 
small business.  Table VIII- 1 shows a summary of the costs and benefits for each 
alternative considered as compared to the Proposed Amendments.  
Table VIII -1. C ost-benefit comparison  of the Proposed Amendments and 
regulatory alternatives  (billion 2019$) . 
(Totals may differ slightly due to rounding.)  
Scenario  Total 
costs  Health benefits  Cost-
savings (benefit)  Tax & fee revenue  Total benefit  Net benefit  Benefit-cost ratio 
Proposed 
Amendmentsy $14.41  $8.82  $10.33  -$0.47 $18.68  $4.27  1.30 
Alternative 1z $14.06  $9.04  $11.57  -$0.73 $19.89  $5.83  1.41 
Alternative 2aa $14.66  $8.20  $8.77  $0.11 $17.09  $2.43  1.17 
Small Business Alternative
bb $11.73  $6.49  $7.23  $0.70 $14.43  $2.70  1.23 
                                            
y Under the Proposed Amendments, the HC + NO x emission standards would be 0  for MY 2024 and 
subsequent model years for all SORE except generator engines. The HC + NO x emission standards for 
generator engines would be 0 for MY 2028 and subsequent model years. For more detail, see II.A.2.  
z Under Alternative 1, the HC + NO x emission standards would be 0 for MY 2024 and subsequent model 
years for all SORE. For more detail, see VIII.A.1.  
aa Under Alternative 2, the HC + NO x emission standards would be more stringent than the existing 
emission standards for MYs 2024 through 2025 for all  SORE. The HC + NO x emission standards would 
be 0 in MY 2026 and subsequent model years for all SORE except generator engines. The HC + NO x 
emission standards for generator engines would be 0 for MY 2030 and subsequent model years. For 
more detail, see VII I.B.1.  
bb Under the Small Business Alternative, the HC + NO x emission standards would be 0 for MY 2028 and 
subsequent model years for all SORE except generator engines. The HC + NO x emission standards for 
generator engines would be 0 for MY 2032 and subsequent model years. For more detail see VIII.C.1.   
117 A. Alternative 1 
1. Description of Alternative 1  
Alternative 1 would increase the adoption of ZEE  faster  than the Proposed 
Amendments and has been suggested by many environmental organizations  and 
members of the public. This alternative would set the emission standard s to zero for all 
SORE, including generators, for  MY 2024 and subsequent model years.  
No further emission reduction credit generation would be possible after MY 2023 . 
Manufacturers could use their remaining credit banks and would likely do so soon er as 
opposed to holding on to them for several years. The analysis assumed that 
manufacturers would use all of their remaining  credits to produce 4.9 percent of the 
number of engines that would have been produced in the Baseline Scenario in MY 
2024 and still meet the proposed emission standard s of zero. The assumption that 
manufacturers would use all of their banked credits in MY 2024 is the most 
conservative assumption from an economic  perspective. The analysis assumes a ll 
equipment sales in 2025 woul d be ZEE if manufacturers used their banked credits for 
MY 2024. If manufacturers used  their banked credits over several model years, the 
economic impact would be smaller in the years in which they used their credits.  
The fraction of ZEE in the overall po pulation would increase sooner  in Alternative 1 , as 
shown in Figure VIII -1, than with the Proposed Amendments (Figure II-3). Under 
Alternative 1, 94.9 percent of the small off -road equipment population subject to the 
SORE regulations w ould be ZEE  in 2035, as compared to  93.4 percent under the 
Proposed Amendments. EO N-79-20 sets a goal “ to transition to 100 percent zero -
emission off -road vehicles and equipment by 2035 where feasible”. The remaining 5.1 
percent would  continue to transition over the following  years, reaching 99.5 percent 
ZEE in 2043 , as compare d to 99.4 percent under the Proposed Amendments .  
118 Figure VIII -1. Modeled small off -road equipment population statewide under  
Alternative 1 . 
 
2. Costs  
Staff assumed that cost inputs would  be the same as in the Proposed Amendments, as 
the only change is the removal of the delay for gener ator adoption of  ZEE. Table VIII-2 
shows annual cost s for Alternative  1. There is no expected increase in upfront costs in 
2028 in Alternative 1 because emission standards for generators would be zero for MY 
2024 and subsequent model years. Instead, annual  costs would gradually increase  as 
population increases. Annual c ost-savings in Alternative 1 would increase as more ZEE 
is adopted. The rate of change in annual cost-savings would decrease  through 2043. In 
2043, annual cost -savings would be approximately  $1.87 billion. Annual net 
cost-savings would occur statewide starting in the year 2035, two years earlier than 
with the Proposed Amendments. Alternative 1 would have  a net  direct cost of $2. 49 
billion accrued through 2043, which is $ 1.59 billion less  than with the Proposed 
Amendments. Figure VIII- 2 illustrates  the total costs and  cost-savings of Alternative 1.  
For reference, the same graphical representation  of direct costs for the Proposed 
Amendments is Figure VII -1.
 
119 Table VIII -2. Modeled costs to professional and residential users per year under  
Alternative 1 relative to the Baseline Scenario  (millions 2019$ ). 
(Negative values indicate cost -savings. Totals may differ slightly due to 
rounding.)  
Year Gasoline 
equipment costs  Electric equipment costs  Gasoline equipment maintenance costs  Gasoline Costs Electricity costs  Total cost s  Total cost -
savings  Net costs  
2023   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2024  -$761.49  $1,420.20  -$13.69  -$52.21  $7.91  $1,428.11  -$827.39   $600.72  
2025  -$806.10  $1,492.66  -$40.63  -$128.30  $19.78  $1,512.44  -$975.03   $537.41  
2026  -$811.54  $1,496.06  -$64.07  -$160.40  $26.44  $1,522.50  -$1,036.01   $486.49  
2027  -$817.03  $1,499.49  -$90.07  -$233.04  $38.24  $1,537.73  -$1,140.14   $397.59  
2028  -$822.59  $1,504.07  -$113.75  -$299.59  $49.85  $1,553.92  -$1,235.93   $317.99  
2029  -$828.20  $1,508.69  -$134.57  -$366.56  $61.10  $1,569.79  -$1,329.33   $240.46  
2030  -$833.89  $1,514.50  -$152.55  -$420.91  $71.88  $1,586.38  -$1,407.35   $179.03  
2031  -$839.63 $1,524.99  -$167.72  -$471.49  $80.47  $1,605.46  -$1,478.84   $126.62  
2032  -$845.44  $1,535.61  -$180.60  -$515.31  $87.95  $1,623.56  -$1,541.35   $82.21  
2033  -$851.31  $1,546.34  -$191.43  -$552.93  $94.30  $1,640.64  -$1,595.67   $44.97  
2034  -$857.25  $1,557.19  -$200.59  -$585.46  $99.72  $1,656.91  -$1,643.30   $13.61  
2035  -$863.25  $1,568.16  -$208.10  -$612.83  $104.26  $1,672.42  -$1,684.18  -$11.76  
2036  -$869.32  $1,579.26  -$214.23  -$635.41  $107.93  $1,687.19  -$1,718.96  -$31.77  
2037  -$875.46  $1,590.47  -$219.18  -$654.27  $110.95  $1,701.42  -$1,748.91  -$47.49  
2038  -$881.67  $1,601.81  -$222.93  -$669.89  $113.41  $1,715.22  -$1,774.49  -$59.27  
2039  -$887.95  $1,613.28  -$226.00  -$682.93  $115.44  $1,728.72  -$1,796.88  -$68.16  
2040  -$894.30  $1,624.88  -$228.28  -$693.85  $117.12  $1,742.00  -$1,816.43  -$74.43  
2041  -$900.72  $1,636.60  -$230.18  -$703.33  $118.57  $1,755.17  -$1,834.23  -$79.06  
2042  -$907.21  $1,648.46  -$231.84  -$711.92  $119.86  $1,768.32  -$1,850.97  -$82.65  
2043  -$913.77  $1,660.44  -$233.35  -$719.84  $121.05  $1,781.49  -$1,866.96  -$85.47  
Average  -$812.77  $1,482.06  -$160.18  -$470.02  $79.34  $1,561.40  -$1,442.97   $118.43  
Total -$17,068.12  $31,123.16  -$3,363.76  -$9,870.47  $1,666.23  $32,789.39  -$30,302.35   $2,487.04   
120 Figure VIII -2. Statewide costs, cost -savings, and overall net costs under 
Alternative  1. 
(Negative values indicate cost -savings.)  
 
3. Benefits  
For emissions modeling in Alternative 1, staff considered the emissions credit banks as 
discu ssed in VIII.A .1. For MY 2024, staff assumed manufacturers would produce 4.9 
percent of the number of engines that would have been produced in the Baseline 
Scenario with both exhaust and evaporative emissions equal to the emissions of the 
current average engine. This percentage is limited by the current evaporative emission 
credit bank, which allow s for the manufacture of fewer average engines than the 
exhaust emission credit bank. The engines produced in MY 2024 would use the 
remaining evaporative emission credit bank , leaving some exhaust credits unused. To 
account for this, staff assumed that all MY 2023 engines would emit 0.74 g·kWh-1 
excess exhaust emissions above the current emission standards, because manufacturers would be unable to use the remaining exhaust emission credits for MY 2024. Table VIII-3 shows annual emission reductions for ROG , NO
x and CO 2. 
Figures VIII- 3 and VIII -4 show the reductions in NO x and ROG  emissions for each 
modeled year.  In 2031, the emission reductions would be 7.9 tpd and 57.4 tpd for 
NO x and ROG , respectively. These represent 7 and 4 percent greater  emission  
reductions , respectively,  than under  the Proposed Amendments.  
Emission reductions would begin in 2024, which is the same as with  the Proposed 
Amendments. Emissions in 2043 under Alternative 1 would be similar to those with the 
Proposed Amendments, approximately  6.2 tpd and 27 tpd, for NO x and ROG , 
respectively. Over the regulatory horizon , this would  lead to a total of 61,299 tons of 
 
121 NO x emission reductions and 432,979 tons of ROG emission reductions, compared to 
the B aseline Scenario . These reductions are only marginally higher than the emission 
reductions under the Proposed Amendments.  
Table VIII-4 shows the avoided health outcomes and the valuation of these outcomes 
as a result of Alternative 1 for the regulatory horizon . The total incidence of avoided 
health outcomes and their valuation are both slightly higher in Alternative 1 as 
compared to the Proposed Amendments.  
  
122 Table VIII -3. Annual average emission reductions under Alternative 1 . 
(Totals may not add up due to rounding.)  
Year ROG emission 
reductions (tpd) NO x emission 
reductions (tpd) CO 2 emission 
reductions 
(MMT/year ) 
2023  -0.13 -0.02 0.00 
2024   3.2  0.45 0.05 
2025   11.1  1.5 0.17 
2026   20.5  2.6 0.29 
2027   29.9  3.8 0.40 
2028   38.4  5.0 0.51 
2029   45.8  6.0 0.60 
2030   52.1  7.0 0.68 
2031   57.4  7.9 0.74 
2032   61.9  8.6 0.80 
2033   65.9  9.3 0.85 
2034   69.4  9.9 0.89 
2035   72.6  10.5 0.92 
2036   75.5  10.9 0.95 
2037   78.1  11.3 0.98 
2038   80.2  11.6 1.0 
2039   82.1  11.9 1.0 
2040   83.7  12.1 1.0 
2041   85.1  12.3 1.0 
2042   86.3  12.5 1.1 
2043   87.3  12.7 1.1 
Average   56.5  8.0 0.72 
Total  432,979  61,299  15.1 
  
123 Figure VIII -3. Annual average NOx emissions under Alternative 1 and the Baseline 
Scenario.  
 
Figure VIII -4. Annual average ROG emissions under Alternative 1 and the Baseline Scenario.  
 
 
 
124 Table VIII -4. Statewide valuation from avoided health outcomes under  
Alternative  1. 
Outcome Avoided incidents  Valuation 
(million 2019$)  
Premature cardiopulmonary mortality  915 $9,027.08  
Cardiovascular hospitalization  145 $8.45  
Acute respiratory hospitalization  173 $8.79  
ER visit  for asthma  450 $0.38  
Total  1,683 $9,044.70  
4. Cost -Effectiveness  
The metric to quantify cost- effectiveness of the Proposed Amendment s and 
Alternative 1 is the ratio of total monetized benefits divided by total monetized costs. A comparison of this type is an appropriate cost- effectiveness measure because the 
harm associated with increased emissions is captured in the estimates of monetized health impacts. A benefit -cost ratio greater than one implies that the benefits of the 
scenario are greater  than its costs. Benefits include both health benefits and 
cost-savings after subtracting tax and fee revenue impacts to state and local 
governments. Table VIII -5 indicates that the Proposed Amendments would have a n 
accrued  net benefit of $4. 27 billion and a benefit -cost ratio of 1. 30, meaning benefits 
would be  greater than costs during the regu latory horizon  of 2023 through 2043. 
Alternative  1 would have  an accrued  net benefit of $5. 83 billion, and a benefit -cost 
ratio of 1. 41, meaning Alternative 1 would be  more cost- effective than the Proposed 
Amendments.  
Table VIII -5. Cost-benefit comparison of the Proposed Amendments and 
Alternative 1 (billion  2019$) . 
Scenario  Total 
costs  Health benefits  Cost-
savings 
(benefit)  Tax & 
fee 
revenue  Total 
benefit  Net benefit  Benefit-cost 
ratio 
Proposed 
Amendments $14.41  $8.82  $10.33  -$0.47  $18.68  $4.27  1.30 
Alternative 1  $14.06  $9.04  $11.57  -$0.73  $19.89  $5.83  1.41 
5. Reason for Rejecting  
Staff rejected Alternative 1  on technological feasibility grounds. The primary reason 
for not pursuing this alternative is to provide more time for the  zero- emission 
generator market to mature. Currently, as noted in I. E.3.b, the availability and variety 
of zero- emission generators is limited. Manufacturers of zero -emission generators may 
not be poised to meet the entire market demand that could occur if  fewer SORE 
generators were produced starting in MY 2024.  Currently, based on population 
modelling done using the SORE2020 model, demand for generators is relatively  
125 constant, year over year. Requiring zero- emission generators  in MY 2024 could 
increase the price of available zero- emission generators due to demand.  This price 
increase would create added costs for resident ial users  and professional users in the 
state.  
One of the leading companies making zero -emission generators that could be 
considered a replacement for a SORE generator  describes on its website  the time 
involved in developing a zero -emission generator. It took over three years from the  
founding of the business to create its  first zero-emission generator with performance 
equivalent to SORE generators ( Goal Zero, 2021 a). Giving manufacturers an additional 
four years before emission standards of zero are implemented for generators would  
ensure adequate  time for product development, ma nufacturing, and marketing of a 
new product.  
The additional four -year period (MYs 2024 through 2027) allowing sale of SORE 
generators that meet more stringent  emission standard s in the Proposed Amendments 
would ease concerns about the need for generators due to PSPS. Some  small portable 
generators are purchased for home backup power, and zero- emission generators that 
can cover a multi -day power outage have a higher purchase price than SORE 
generators.  
B. Alternative 2  
1. Description of Alternative 2  
Altern ative 2 would allow for a more gradual adoption of ZEE  than the Proposed 
Amendments. Starting in MY 2024, more stringent exhaust and evaporative emission 
standards would be implemented for all SORE. Then, in MY 2026, the emission standards would be zero fo r SORE used in all equipment except generators. The 
emission standards for generator engines would be zero for MY 2030 and subsequent 
model years . This alternative would allow for a slower uptake of ZEE, and allow 
manufacturers who have invested in and are producing lower -emitting SORE to 
continue to do so for a few more model year s. Tables VIII-6 through VIII -9 show the 
emission standards for this alternative.  
Emission reduction credit generation wo uld be allowed for all SORE through MY 2025 
and exclusively for generators through MY 2029.  Based on CARB’s historical records 
of the emission reduction credit banks, the sum of banked credits has remained  
relatively constant over the last several years.  Therefore, to evaluate this alternative 
staff assumed that  the amount of banked credits at the end of MY  2023 would be 
equal  to the amount at the end of MY 2018 and that the banked credits would all be 
used in MY s 2024 through  2025  for all equipment types. S taff d id not assume any 
manufacturer preference for one equipment type over another .  
In terms of emissions modeling, this means that all SORE produced in MYs 2024 
through  2025 could emit slightly above the emission standards, as shown in Tables 
VIII-6 and VIII -8. The cost would be slightly lower than in a scenario in which only 
equipment that met the emission standards were produced . The population of ZEE  
126 would grow more gradually than in the Proposed Amendments, as shown in  Figure 
VIII-5 , given that e mission standards for SORE generators would not be zero until MY 
2030. Under Alternative 2, 89.3 percent of the small off -road equipment population 
subject to the SORE regulations would be ZEE  in 2035, as compared to 93.4 percent 
under the Proposed Amendments . The remaining 1 0.7 percent would  continue to  
turnover to ZEE  over the following years, reaching 98.8 percent ZEE in 2043, as 
compared to 99.4  percent under the Proposed Amendments . 
Table VIII -6. MYs 2024- 2025 SORE exhaust emission standards and emission level s 
assuming complete use of banked credits under  Alternative 2 . 
Displacement  category Emissions 
durability 
period  
(hours) HC + NO x 
emission 
standard  
(g·kWh-1) HC + NO x 
emission level 
with credit use 
(g·kWh-1) 
< 50 cc, handheld  300 20.0 22.5 
50-80 cc, inclusive,  handheld  300 13.0 15.2 
> 80 cc - < 225 cc, handheld  500 6.0 6.4 
< 225 cc, nonhandheld  500 6.0 6.4 
225-825 cc, inclusive  1,000 3.0 3.3 
> 825 cc  1,000 0.80 1.3 
Table VIII -7. MYs 2026- 2029 exhaust emission standards under  Alternative 2 . 
Displacement  category Emissions 
durability period 
(hours) HC + NO
x 
emission standard 
for generators  
(g·kWh-1) HC + NO x 
emission standard for all other SORE  
(g·kWh
-1) 
< 225 cc  500 6.0 0.00 
225-825 cc, inclusive  1,000 3.0 0.00 
> 825 cc  1,000 0.80 0.00  
127 Table VIII -8. MYs 2024- 2025 SORE evaporative emission standards and emission 
levels assuming complete use of banked credits  under  Alternative 2 . 
(Totals may not add up due to rounding.)  
Displacement  
category Hot soak plus 
diurnal 
emission standard 
(g·test
-1) Hot soak plus 
diurnal 
emission level with 
credit use 
(g·test
-1) Hot soak 
emission 
level with 
credit use 
(g·test-1) Diurnal  
emission 
level with 
credit use 
(g·test-1) 
≤ 80 cc  0.50 0.55 0.13 0.42 
> 80 cc - < 225 cc, 
except  walk-behind 
mowers  0.60 0.61 0.06 0.56 
> 80 cc - < 225 cc 
walk-behind 
mowers  0.60 0.61 0.06 0.56 
≥ 225 cc  0.70 0.75 0.11 0.64 
Table VIII -9. MYs 2026- 2029 evaporative emission  standards and emission levels  
under  Alternative 2 . 
Displacement  
category Hot soak plus 
diurnal 
emission standard for generators  
(g·test
-1) Hot soak 
emission level for 
generators  
(g·test
-1) Diurnal 
emission level for 
generators  
(g·test
-1) Hot soak plus 
diurnal emission standard for all other SORE   
(g·test
-1) 
≤ 80 cc  0.50 0.12 0.38 0.00 
> 80 cc - < 225 cc, 
except  walk-behind 
mowers  0.60 0.06 0.54 0.00 
> 80 cc - < 225 cc 
walk-behind 
mowers  0.60 0.06 0.54 0.00 
≥ 225 cc  0.70 0.10 0.60 0.00  
128 Figure VIII -5. Modeled small off -road equipment population statewide under 
Alternative 2. 
 
2. Costs  
For MYs 2024 through  2025, SORE produced for sale  or lease for use or operation in 
California would be required to  meet the more stringent emission standards in Tables 
VIII-6 and VIII -8 in Alternative 2 . Staff used manufacturers’  certificati on data to identify 
existing equipment that meet the se emission standard s. An example unit for each 
SORE  equipment  category was used to estimate  the price of SORE equipment in 2024 
and 2025. The specific equipment used as the representative examples are identified 
in Tables G -5 and G -6 of the SRIA  in Appendix I  of this Staff Report. Snow  blowers  are 
not required to certify to or comply with  the HC + NO x emission standard s as set out 
in the regulations, but are required to meet the CO emission standar ds. The CO 
emission standards  in this alternative would  not change from the existing emission 
standards ; therefore, it is assumed that currently compliant snow  blowers  would not 
be affected . 
As described in VIII.B.1 , staff assumed banked  credits would be completely used for 
MYs 2024 through  2025 engines. Staff calculated that manufacturers would be able to  
use credits  to produce 3.5 percent of the number of engines that would have been 
produced in the Baseline Scenario for MYs 2024 through 2025 a nd still meet the 
emission standards in Alternative 2. This would fully use t he credits bank ed as of the 
end of  MY 2023  if the amount of banked credits were the same  as the amount at the 
end of MY 2018. Therefore, in the cost  analysis for this alternative,  staff assumed that 
the purchase price of 3.5 percent of new engine production in MYs 2024 through 2025 
would be equal to that of  currently compliant equipment  for all categories. S taff 
assumed all generators would compl y with the emission standards  in Tables VIII-7 and 
 
129 VIII-9 for MYs 2026 through 2029 because no credits would remain after MY 2025 . The 
prices used in the SRIA  for the MY s 2026 through 2029 generators in Alternative 2  are 
the same as those used for MY s 2024 through 2025, since the emis sion standard s are 
the same .  
Table VIII- 10 shows the upfront and ongoing costs in Alternative 2 for each year  from 
2023 through 2043. Figure VIII -6 graphically shows the total costs and cost -savings. 
For reference, the same graphical representation of direct costs for the Proposed 
Amendments is Figure VII -1. Assuming that price and continued availability of SORE 
equipment would influence consumers ’ purchases, less ZEE would be purchased over 
the regulatory horizon  under Alternative 2  than under the Proposed Amendments.  
Therefore, annual  cost-savings from purchasing and using ZEE would not be realized 
until 2026, because ZEE would not make any gains in market share relative to the Baseline Scenario if SORE equipment were still readily availa ble. Annual n et 
cost-savings would be realized statewide starting in the year 2039. The  net direct cost 
of this alternative  accrued  through 2043 would be  $5.88 billion. This is $1 .81 billion 
dollars more than the Proposed Amendments would cost over the sam e regulatory 
horizon .  
130 Table VIII -10. Modeled costs to professional and residential users per year under  
Alternative 2 relative to the B aseline Scenario  (millions 2019$) .  
(Negative values indicate cost -savings.  Totals may differ slightly due to 
rounding.)  
Year Gasoline 
equipment costs  Electric equipment costs  Gasoline equipment maintenance costs  Gasoli ne 
costs  Electricity costs  Total costs  Total cost -
savings  Net costs  
2023   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2024   $738.73  $0.00   $0.00   $0.00  $0.00  $738.73   $0.00   $738.73  
2025   $744.77  $0.00   $0.00   $0.00  $0.00  $744.77   $0.00   $744.77  
2026  -$59.22  $853.02  -$11.82  -$19.79  $4.03  $857.05  -$90.83   $766.22  
2027  -$55.69  $852.02  -$34.34  -$57.39  $11.04  $863.06  -$147.42   $715.64  
2028  -$52.11  $851.60  -$58.44  -$97.23  $18.87  $870.47  -$207.78   $662.69  
2029  -$48.48  $851.20  -$81.68  -$137.94  $26.76  $877.96  -$268.10   $609.86  
2030  -$833.89  $1,514.50  -$103.25  -$180.26  $35.40  $1,549.90  -$1,117.40   $432.50  
2031  -$839.63  $1,524.99  -$123.88  -$240.69  $45.72  $1,570.71  -$1,204.20   $366.51  
2032  -$845.44  $1,535.61  -$142.40  -$304.05  $56.26  $1,591.87  -$1,291.89   $299.98  
2033  -$851.31  $1,546.34  -$158.28  -$362.81  $65.96  $1,612.30  -$1,372.40   $239.90  
2034  -$857.25  $1,557.19  -$172.10  -$417.40  $74.91  $1,632.10  -$1,446.75   $185.35  
2035  -$863.25  $1,568.16  -$184.01  -$467.36  $82.93  $1,651.09  -$1,514.62   $136.47  
2036  -$869.32  $1,579.26  -$194.31  -$512.89  $90.11  $1,669.37  -$1,576.52   $92.85  
2037  -$875.46  $1,590.47  -$202.95  -$553.34  $96.40  $1,686.87  -$1,631.75   $55.12  
2038  -$881.67  $1,601.81  -$210.16  -$588.17  $101.72  $1,703.53  -$1,680.00   $23.53  
2039  -$887.95  $1,613.28  -$216.09  -$618.32  $106.26  $1,719.54  -$1,722.36  -$2.82  
2040  -$894.30  $1,624.88  -$220.73  -$644.21  $110.11  $1,734.99  -$1,759.24  -$24.25  
2041  -$900.72  $1,636.60  -$224.58  -$666.10  $113.34  $1,749.94  -$1,791.40  -$41.46  
2042  -$907.21  $1,648.46  -$227.47  -$684.07  $115.96  $1,764.42  -$1,818.75  -$54.33  
2043  -$913.77  $1,660.44  -$229.86  -$699.25  $118.18  $1,778.62  -$1,842.88  -$64.26  
Average  -$521.58  $1,219.52  -$133.16  -$345.30  $60.66  $1,350.82  -$1,070.68   $280.14  
Total -$10,953.17  $25,609.83  -$2,796.35  -$7,251.27  $1,273.96  $28,367.29  -$22,484.29   $5,883.00   
131 Figure VIII -6. Statewide costs, cost -savings, and overall net costs under 
Alternative  2.  
(Negative values indicate cost -savings.)  
 
3. Benefits  
Table VIII-11 shows the annual emission reductions for ROG , NO x, and CO 2 for 
Alternative 2 . Figur es VIII- 7 and VIII -8 show the emission reductions for NO x and ROG  
for each year from 2023  through 2043 . Emission reductions would occur later in 
Alternative 2 compared to the Proposed Amendments. In 2031, the emissions 
reductions would be 6.8 tpd and 50.2 tpd for NO x and ROG , respectively. These 
emission reductions are 9 and 8 percent, respectively,  less than with the Proposed 
Amendments.  
 Over the regulatory horizon , this would  lead to a total of 56,495 tons of NO x 
emissions reductions and 395,438 tons of ROG emissions reductions, compared to the 
Baseline Scenario . These emission reductions are 5 and 7 percent less than the 
emission reductions expected with  the Proposed Amendments for NO x and ROG , 
respectively.  
 
132 Table VIII -11. Annual average emission reductions under  Alternative 2.  
(Totals may not add up due to rounding.)  
Year ROG emission 
reductions (tp d) NO x emission 
reductions (tpd)  CO 2 emission 
reductions ( MMT/year ) 
2023  0.00 0.00 0.00 
2024  1.8 0.26 0.00 
2025  6.1 0.82 0.00 
2026  12.8 1.7 0.05 
2027  21.2 2.8 0.14 
2028  29.7 3.8 0.23 
2029  37.4 4.9 0.32 
2030  44.2 5.8 0.40 
2031  50.2 6.8 0.49 
2032  55.5 7.7 0.58 
2033  60.0 8.5 0.65 
2034  64.0 9.2 0.72 
2035  67.5 9.8 0.78 
2036  70.7 10.3 0.83 
2037  73.6 10.8 0.88 
2038  76.3 11.2 0.92 
2039  78.7 11.6 0.95 
2040  80.9 11.9 0.98 
2041  82.7 12.1 1.0 
2042  84.3 12.4 1.0 
2043  85.8 12.6 1.1 
Average  51.6 7.4 0.57 
Total  395,438  56,495  12.0  
133 Figure VIII-7. Annual average NOx emissions under  Alternative 2 and the Baseline 
Scenario . 
 
Figure VIII -8. Annual average ROG emissions under  Alternative 2 and the Baseline 
Scenario . 
 
 
134 Table VIII-12 shows t he avoided health outco mes under  Alternative 2  and the valuation 
of these outcomes during  the regulatory horizon . The total number of avoided health 
inciden ts and their valuation are both slightly smaller than in the Proposed 
Amendments.  
Table VIII-12. Statewide valuation from avoided health outcomes under  
Alternative 2 . 
Outcome Avoided incidents  Valuation 
(million 2019$)  
Premature cardiopulmonary mortality  830 $8,188.50  
Cardiovascular hospitalization  132 $7.69 
Acute respiratory hospitalization  158 $8.03 
ER visit for asthma  407 $0.34  
Total  1,528 $8,204.56  
4. Cost -Effectiveness  
Table VIII-13 indicates that the Proposed Amendments would have a n accrued net  
benefit of $ 4.27 billion and a benefit -cost ratio of 1. 30, meaning benefits would be  
greater than costs during the regulatory horizon  of 2023 through  2043. Alternative 2 
would have  an accrued  net benefit of $ 2.43 billion, and a benefit -cost ratio of 1. 17, 
meaning that Alternative 2 would be  less c ost-effective than the Proposed 
Amendments.  
Table VIII-13. Cost-benefit comparison of the Proposed Amendments and 
Alternative 2 (billion  2019$) . 
Scenario  Total 
costs  Health benefits  Cost-
savings (benefit)  Tax & fee revenue  Total benefit  Net benefit  Benefit-cost ratio 
Proposed 
Amendments $14.41  $8.82  $10.33  -$0.47  $18.68  $4.27  1.30 
Alternative 2  $14.66  $8.20  $8.77  $0.11  $17.09  $2.43  1.17 
5. Reason for Rejecting  
Staff rejected Alternative 2 for two reasons.  First, Alternative 2 would not be as 
cost-effective as the Proposed Amendments or Alternative 1. Alternative 2 would have 
a $1.81 billion higher direct cost and a lower benefit -cost ratio  than the Proposed 
Amendments. Second, Alternative 2 would make it more difficult for CARB to achieve 
its air q uality goals both under EO  N-79-20 and the 2016 State SIP Strategy. Under  
135 Alternative 2, only 89.3 percent of the small off -road equipment population subject to 
the SORE regulations would  be ZEE  in 2035, as compared to 93.4 percent under the 
Proposed Amend ments . The remaining 10 .7 percent would  continue to turnover to 
ZEE over the following years, reaching 98.8 percent ZEE in 2043. E mission benefits 
under Alternative 2 in 2031 would  be 6.8 tpd and 50.2 tpd of NO x and ROG , 
respectively. These emission reductions are both smaller than those that would occur 
with the Proposed Amendments. While these emission reductions would  meet the 
2016 State SIP Strategy expected emission reductions for SORE, they would fail to 
maximize health benefits that c ould be achieved and would make less progress  toward  
statewide commitments . As provided in CARB’s enabling statutory authority, “[t]he 
control and elimination of  … air pollutants is of prime importance for the protection 
and preservation of the public health a nd well -being, and for the prevention of 
irritation to the senses, interference with visibility, and damage to vegetation and 
property.” (HSC section 43000, subd. (b)) . Therefore, since public health benefits are 
one of the primary purposes of  CARB’s statu tory mandate for adopting and 
implementing regulations, like the Proposed Amendments, Alternative 2’s failure to maximize health benefits to the same extent as the Proposed Amendments would not be consistent with HSC section 43000, sub section  (b), and it must be rejected  for this 
reason and on cost -effectiveness grounds.  
C. Small Business Alternative 
Government Code section 11346.2(b)(4)(B) requires a description of reasonable alternatives to the regulation that would lessen any adverse impact on small 
businesses and the agency's reasons for rejecting those alterna tives. The Proposed 
Amendments to the SORE regulation s could  have an impact on costs to small 
businesses. The primary category of small business directly impacted by the regulation 
would be  landscapers, who would  have a higher upfront cost for ZEE.  
1. Description of Alternative  
The Small Business Alternative would push the increase in adoption of  ZEE to a later 
time than the Proposed Amendments and would avoid the higher upfront cost of 
lower emitting gasoline -powered equipment . Current emission standards would 
remain in place through MY  2027. For MY 2028, the emission standard s would be zero 
for all small off -road equipment, except generators. Beginning in MY 2028, g enerators 
would be subje ct to the same emission  standards as they would in MYs 2024 through 
2027 under  the Proposed Amendments (Tables II- 1 and II -2). These emission standards 
would remain in place  through  MY 2031. For MY 2032, the generator emission 
standard s would be zero.  This alternative would delay the adoption of  ZEE to continue 
to allow for the development of the ZEE market, especially for  professional 
equipment . 
Credit generation c ould continue for all SORE through  MY 2027 and exclusively for 
generators through  MY 2031 . To analyze this alternative, staff assumed that in MY 
2024 and subsequent model years  there would be no excess credit generation ( i.e., no  
136 excess credits would be banked  and credit banks would remain constant ). The amount 
of banked credits at the end of MY 2027 would therefore be equal to the amount of 
banked credits at the end of MY 2018.  This assumption means any generation and use 
of credits during or after  MY 2024 would not affect costs or emissions modeling. It is 
assumed that the credit banks would  be used for MYs 2028 through 2031 generators.  
Use of banked  credits would allow 6.3  percent of all generators produced  between 
MYs 2028 and 2031 to have emission levels equivalent to the current average. The 
price of those 6.3 percent of  generators would  be the same as that of currently 
compliant generators . The rest of the MY s 2028  through  2031 generators were 
assumed to have  the same price as MY s 2024 through 2027 generators under  the 
Proposed Amendments.  The population of ZEE would grow more gradually than in the 
Proposed Amendments, as shown in Figure VIII -9, because emission standards for  
generators would not  be zero until MY 2032 .  
Under the Small Business Alternative , 83.9 percent of equipment  subject to the SORE 
regulations would  be ZEE in 2035 , as compared to 93.4 percent under the Proposed 
Amendments. The remaining 16 .1 percent would  continue to turn over to ZEE over the 
following years, reaching 97 .8 percent ZEE in 2043, as compared to 99.4 percent 
under the Proposed Amendments. 
Figure VIII -9. Modeled small off-road equipment population statewide under  the 
Small Business Alternative. 
 
 
137 2. Costs  
Staff assumed that cost inputs would be the same as in the Proposed Amendments, as 
the only change would be in  the overall timing of  implementation. Table VIII-14 shows 
annual cost s for the Small Business Alternative.  Figure VIII- 10 graphically shows t he 
total costs and cost- savings. For reference, the same graphical representation of direct 
costs for the Proposed Amendments is Figure VII -1. Costs and cost -savings would 
increase and decrease  in a similar manner to those for  the Proposed Amendments. 
Annual n et cost- savings would occur statewide starting in the year 2041, four years 
later than with the Proposed Amendments. The Small Business Alternative w ould have 
a net  direct cost of $ 4.50 billion accrued  through 2043, which is $419 m illion higher 
than the Proposed Amendments . 
  
138 Table VIII -14. Modeled costs to professional and residential users per year under  
the Small Business Alternative relative to the B aseline Scenario  
(millions 2019$). 
(Negative values indicate cost -savings. Totals may differ slightly due to 
rounding.)  
Year Gasoline 
equipment 
costs  Electric 
equipment 
costs  Gasoline 
equipment 
maintenance costs  Gasoline 
Costs Electricity costs  Total costs  Total cost -
savings  Net costs  
2023   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2024   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2025   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2026   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2027   $0.00  $0.00   $0.00   $0.00  $0.00  $0.00   $0.00   $0.00  
2028  -$78.96  $851.60  -$11.83  -$20.04  $4.18  $855.78  -$110.83   $744.95  
2029  -$75.66  $851.20  -$34.36  -$58.21  $11.44  $862.64  -$168.23   $694.41  
2030  -$72.31  $851.39  -$58.49  -$98.14  $19.58  $870.97  -$228.94   $642.03  
2031  -$68.91  $853.93  -$81.74  -$137.50  $27.36  $881.29  -$288.15   $593.14  
2032  -$845.44  $1,535.61  -$103.35  -$181.24  $35.62  $1,571.23  -$1,130.03   $441.20  
2033  -$851.31  $1,546.34  -$124.06  -$242.51  $46.07  $1,592.41  -$1,217.88   $374.53  
2034  -$857.25  $1,557.19  -$142.66  -$306.88  $56.75  $1,613.94  -$1,306.79   $307.15  
2035  -$863.25  $1,568.16  -$158.63  -$366.62  $66.60  $1,634.76  -$1,388.50   $246.26  
2036  -$869.32  $1,579.26  -$172.54  -$422.16  $75.68  $1,654.94  -$1,464.02   $190.92  
2037  -$875.46  $1,590.47  -$184.53  -$473.02  $83.84  $1,674.31  -$1,533.01   $141.30  
2038  -$881.67  $1,601.81  -$194.90  -$519.41  $91.14  $1,692.95  -$1,595.98   $96.97  
2039  -$887.95  $1,613.28  -$203.62  -$560.64  $97.54  $1,710.82  -$1,652.21   $58.61  
2040  -$894.30  $1,624.88  -$210.88  -$596.14  $102.96  $1,727.84  -$1,701.32   $26.52  
2041  -$900.72  $1,636.60  -$216.87  -$626.89  $107.58  $1,744.18  -$1,744.48  -$0.30  
2042  -$907.21  $1,648.46  -$221.56  -$653.31  $111.50  $1,759.96  -$1,782.08  -$22.12  
2043  -$913.77  $1,660.44  -$225.45  -$675.65  $114.79  $1,775.23  -$1,814.87  -$39.64  
Average  -$516.36  $1,074.79  -$111.69  -$282.78  $50.13  $1,124.92  -$910.82  $214.09  
Total -$10,843.49  $22,570.62  -$2,345.47  -$5,938.36  $1,052.63  $23,623.25  -$19,127.32  $4,495.93   
139 Figure VIII -10. Statewide costs, cost-savings, and overall n et costs under  the Small  
Business Alternative. 
(Negative values indicate cost -savings.)  
 
3. Benefits  
Table VIII-15 shows the annual emission reductions f or ROG, NO x, and CO 2, under the 
Small Business Alternative. Figures VIII- 11 and VIII -12 show t he emission reductions for 
NO x and ROG  for each modeled year. Emission reductions would occur late r in the 
Small Business Alternative as compared to the Proposed Amendments. In 2031, the 
emissions reductions would be 3.5 tpd and 28.7 tpd for NO x and ROG , respectively. 
These emission reductions are 53 and 48 percent, respectively,  less than with the 
Proposed Amendments.  Over the regulatory horizon  this would lead to a total of 
42,429 tons of NO x emission reductions, and 303,490 tons of ROG emission 
reductions , compared to the B aseline Scenario . These emission reductions are 
28 percent less than the emission reductions expected with  the Proposed 
Amendments for  both  NO x and ROG . 
 
140 Table VIII -15. Annual average emission reductions under  the Small Business 
Alternative . 
(Totals may not add up due to rounding.)  
Year ROG emission 
reductions (tpd)  NO x emission 
reductions (tpd)  CO 2 emission 
reductions ( MMT/year ) 
2023  0.00 0.00 0.00 
2024  0.00 0.00 0.00 
2025  0.00 0.00 0.00 
2026  0.00 0.00 0.00 
2027  0.00 0.00 0.00 
2028  3.4 0.48 0.05 
2029  11.0 1.4 0.14 
2030  19.9 2.4 0.23 
2031  28.7 3.5 0.32 
2032  36.7 4.6 0.40 
2033  44.0 5.6 0.49 
2034  50.3 6.6 0.58 
2035  55.7 7.6 0.65 
2036  60.5 8.4 0.72 
2037  64.7 9.2 0.78 
2038  68.5 9.8 0.84 
2039  72.0 10.4 0.88 
2040  75.2 11.0 0.93 
2041  78.0 11.4 0.96 
2042  80.5 11.8 0.99 
2043  82.6 12.1 1.02 
Average  39.6 5.5 0.47 
Total  303,490  42,429  10.0  
141 Figure VIII -11. Annual average NOx emissions under the Small Business 
Alternative and the Baseline Scenario . 
 
Figure VIII -12. Annual average ROG emissions under the Small Business 
Alternative and the B aseline Scenario . 
 
 
 
142 Table VIII-16 shows the avoided health outcomes as a result of the Small Business 
Alternative  and the valuation of these o utcomes during  the regulatory horizon . The 
total number of avoided inciden ts and t heir valuation are both  smaller than in the 
Proposed Amendments.  
Table VIII -16. Statewide valuation from avoided health outcomes under  the Small 
Business Alternative. 
Outcome Avoided incidents  Valuation 
(million 2019$)  
Premature cardiopulmonary mortality  657  $6,481.74  
Cardiovascular hospitalization  106  $6.18  
Acute respiratory hospitalization  127  $6.46  
ER visit  for asthma  321  $0.27  
Total  1,211 $6,494. 64 
4.Cost -Effectiveness  
Table VIII-17 indicates that the Proposed Amendments have an accrued  net benefit of 
$4.27 billion and a benefit -cost ratio of 1. 30, meaning benefits would be  greater than 
costs during the regulatory horizon  of 2023 through 2043. The Small Business 
Alternative would have  an accrued  net benefit of $ 2.70 billion, and a benefit -cost ratio 
of 1.23, meaning that the Small Business Alternative would be  less cost -effective than 
the Proposed Amendments.  
Table VIII-17. Cost-benefit comparison of the Proposed Amendments and the 
Small Business Alternative (billion  2019$) . 
Scenario  Total 
costs Health benefits  Cost-
savings (benefit)  Tax & fee revenue  Total benefit  Net benefit  Benefit-cost ratio 
Proposed 
Amendments $14.41  $8.82  $10.33  -$0.47  $18.68  $4.27  1.30 
Small Business Alternative  $11.73  $6.49  $7.23  $0.70  $14.43  $2.70  1.23 
5. Reason for Rejecting  
Staff reject ed the Small Business Alternative due to its  failure to meet expected 
emissions reductions in the 2016 State SIP Strategy. The 2016 State SIP Strategy 
expects  4 tpd of NO x emission reductions and 36 tpd of ROG emission reductions in 
2031 from the SORE category. Emission benefits under the Small Business Alternative 
in 2031 would be 3.5  tpd and 28.7 tpd of NO x and ROG , respectively.  Under the Small  
143 Business Alternative, only 83.9 percent of equipment subject to the SORE regulations 
would  be ZEE  in 2035. Approximately 10 percent less of the small  off-road equipment 
population would be ZEE in 2035 under the Small Business Alternative than with the 
Proposed Amendments. 
The Small Business Alternative would , also,  fail to maximize health benefits that can be 
achieved. As provided in CARB’s enabling st atutory authority, “[t]he control and 
elimination of  … air pollutants is of prime importance for the protection and 
preservation of the public health and well -being, and for the prevention of irritation to 
the senses, interference with visibility, and dama ge to vegetation and property.” 
(HSC  section 43000, subd. (b) ). Therefore, since public health benefits are one of the 
primary purposes of  CARB’s statutory mandate for adopting and implementing 
regulations, like the Proposed Amendments, the Small Business Alternative’ s failure to 
maximize health benefits to the same extent as the Proposed Amendments would not 
be consistent with HSC section 43000, subsection (b) , and it must be rejected for this 
reason, and on the other listed grounds.  
D. Performance Standards in Place of Prescriptive Standards 
Government Code section 11346.2(b)(4)(A) requires that when CARB proposes a regulation that would mandate the use of specific technologies or equipment, or 
prescribe specific actions or procedures, it must consider performance standards as an 
alternative . The Proposed Amendments to the SORE regulation s, which would set  
more stringent  emission standards and increase adoption of ZEE , are performance 
standards, as they do not prescribe the type of technology that must be u sed or 
explicitly require the purchase of a certain type of equipment.  Therefore, the 
requirements of Government Code section 11346.2(b)(4)(A)  do not apply to the 
Proposed Amendments.  
E. Health and Safety Code S ection 57005 Major Regulation Alternatives  
CARB estimates the Proposed Amendments will have an economic impact on the 
state’s business enterprises of more than $10 million in one or more years of implementation . CARB will evaluate alternatives submitted to CARB and consider 
whether there is a less co stly alternative or combination of alternatives that would be 
equally as effective in achieving increments of environmental protection in full compliance with statutory mandates within the same amount of time as the proposed regulatory requirements, as required by HSC  section 57005.  
IX. Justification for Adoption of  Regulations Different f rom Fede ral 
Regulations Contained in the Code of Federal  Regulations 
When California’s SORE exhaust emission standards were adopted in 1990, and when California’s SORE evaporative emission standards were adopted in 2003, no 
comparable federal rules existed. In 1995, U.S. EPA adopted 40 CFR Part 90, to  
144 control exhaust emissions from new nonroad spark -ignition engines at or below 19 
kW, and in 2008, U.S. EPA adopted 40 CFR  Parts 1054 and 1060, to control exhaust 
emissions from new , small nonroad spark -ignition engines and equipment  and 
evaporative emissions from new and in- use nonroad and stationary equipment, 
respectively. Subsequent California rulemakings in 2011 and 2016  helped to align 
California’s exhaust and evaporative test and certification procedures with federal 
requirements, but differences remain between the two sets of regulations.  
Significant additional stringency in California regulations of SORE is justified in light of 
California’s unique air quality concerns. Low rates of  compliance with evaporative 
emission standards in CARB’s validation studies, compliance testing and other testing  
suggest the expected emission reduction benefits of CARB’s regulations have not 
been completely realized.  Replacing new SORE equipment with ZEE would ensure 
emission reductions are achieved , as expected under the 2016 State SIP Strategy . 
California’s SORE exhaust and evaporative emission regulations, as specified in Title 
13, Cal ifornia Code of Regulations, sections 2400- 2409 and 2750- 2774, are already 
equivalent to or mo re stringent than the existing federal standards. However, even 
with equivalent or more stringent  emission standards for SORE, the total contribution 
of NO x and ROG  from SORE in summer in California, approximately 141  tons per day  
in 2021, is approximately equal to the NO x and ROG  emission s from light- duty 
passenger cars, according to the most recent inventories, SORE2020 and EMFAC2021. Furthermore, significant portions of California, particularly the South Coast and San Joaquin Valley a ir basins, remain severe or extreme ozone 
nonattainment areas. The measure defined in the 2016 State  SIP Strategy to add ress 
this continuing nonattainment will require significant reductions of both  NO
x and ROG  
emissions from SORE . These expected emission reductions cannot be achieved , and 
the associated public health and environmental benefits cannot be realized, without 
adopting significantly more strin gent emission standards than the current f ederal 
emission standards.  
Staff’s proposal would deviate from, and be more stringent than federal requirements 
as follows:  
Beginning with MY  2024, the HC+NO x standard for exhaust emissions would be  zero 
grams per kilowatt- hour for all equipment , except generators. Generators would be 
subject to more stringent emission standards for MY s 2024 through 2027. E xhaust 
emission standards for generators would  be zero grams per kilowatt- hour for MY 2028  
and subsequent model years, as described in Table s IX-1 and IX -2. The more stringent 
emission standards are necessary to achieve the greater level of control of exhaust 
emissions needed in California  to meet its SIP commitments .   
145 Table IX-1. Current SORE exhaust emission standards and exhaust emission 
standards under the Proposed Amendments.  
Displacement  
category Current  HC + NO x 
emission 
standardcc  
(g·kWh-1 ) Proposed HC + NO
x emission 
standard for MYs 2024- 2027 
generators
dd 
(g·kWh-1)  Proposed HC + NO
x emission 
standar d for all 
other SORE for 
MY 2024 and later  
(g·kWh-1) 
< 50 cc  50 6.0 0.00 
50-80 cc, inclusive  72 6.0 0.00 
> 80 cc - < 225 cc  10.0 6.0 0.00 
225-825 cc, inclusive  8.0 3.0 0.00 
> 825 cc  8.0 0.80 0.00 
Table IX-2. Current SORE evaporative emission standards and evaporative 
emission standards under the Proposed Amendments. 
Displacement 
category Current diurnal 
emission standard  
(g·day-1) Proposed hot soak plus diurnal emission standard
ee 
for MY s 2024- 2027 
generators (g·test-1) Proposed hot soak plus diurnal emission standard for all other SORE for MY 2024 and later (g·test
-1) 
≤ 80 cc  N/A 0.50 0.00 
> 80 cc - < 225 cc 
except  walk-behind 
mowers  0.95 + 0.056 × 
nominal capacity 
(liters)  0.60 0.00 
> 80 cc - < 225 cc 
walk-behind mowers  1.0 N/A 0.00 
≥ 225 cc  1.20 + 0.056 × 
nominal capacity 
(liters)  0.70 0.00 
                                            
cc g·kWh-1: grams (g) of emissions per kilowatt -hour (kWh). A kilowatt -hour is a unit of energy equal to 
one kilowatt of power sustained for one hour.  
dd For MY 2028 and subsequent model years, the proposed exhaust emission standard s for generators 
are 0.00 g·kWh-1 for HC + NO x. 
ee For MY 2028 and subsequent model years, the proposed evaporative emission standard s for 
generators are 0.00 g·test-1.  
146 CO emission standards for SORE would  also be more stringent for some engines 
beginning with MY  2024, as shown in Table  IX-3. The CO emission standards for 
generators would  be more stringent  beginning with MY  2024.  The CO emission 
standard s for marine generator engines would be 4.5 g ·kWh-1, which are  consistent 
with the CO emission standard s set by U.S.  EPA for marine generators tested with 
California test fuel.  The more stringent emission standards for CO from generators are 
necessary to avoid adverse health outcomes associated with exposure to CO from 
generators . CO emission standards would not change f or engines with displacement 
less than or equal to 825 cc used in  all other equipment . The CO emission standard  for 
engine s with  displacement greater than 825 cc would be  the same as for LSI engines 
with displacement  greater than 825 cc. 
Table IX-3. Current SORE exhaust CO emission standards and exhaust CO emission 
standards under the Proposed Amendments. 
Displacement  
category Current 
CO emission 
standard  
(g·kWh-1) Proposed 
CO emission 
standardff for 
MY 2024 and later 
generators  
(g·kWh-1) Proposed CO emission 
standar d for  
MY 2024 and later   
for all other SORE  
(g·kWh
-1) 
< 50 cc  536 400 536 
50-80 cc, inclusive  536 400 536 
> 80 cc - < 225 cc  549 400 549 
225-825 cc, inclusive  549 200 549 
> 825 cc  549 20.6 20.6 
The California PM exhaust emission standard s for two-stroke generator engines with 
displacement less than or equal to 80 cc  would  continue to be 2.0 grams per 
kilowatt- hour for MYs 2024 t hrough 2027. The California PM exhaust emission 
standard s for two -stroke engines with displacement less than or equal to 80 cc used in 
all other equipment would  be zero beginning with MY  2024. Federal regulations have 
no PM emission standard s for SORE . The more  stringent emission standards are 
necessary to achieve the greater level of exhaust emissions control  needed in 
California. 
Current requirements for Califo rnia include evaporative emission standards for diurnal 
emissions that control all sources of evaporative emissions from SORE, whereas the 
federal requirements only control fuel tank permeation, fuel line permeation, and 
running loss emissions. The Propose d Amendments would change to a hot soak plus 
                                            
ff The proposed exhaust emission standard s for CO for marine gen erator engines are  4.5 g·kWh-1  
147 diurnal emission standard for MY 2024  and sunset fuel tank and fuel line permeation 
emission standards for engines with displacement of  80 cc  or smaller. The more 
stringent emission standards are necessary to ac hieve the greater level of control of 
evaporative emissions needed in California.  
The Proposed  Amendments for California specify that an engine family subject to 
exhaust compliance testing fails if any of the tested engines yields emission results 
above th e applicable emission sta ndard. C omparable federal regulations require a 
certain number of engines be tested  to determine success or failure.  The number of 
engines tested for federal compliance testing depends on the projected family sales 
and the pass or failure rate at each stage. By requiring every tested unit or component 
to comply with emission standards, staff expects that manufacturers will place a 
greater emphasis on quality control and consistently  producing compliant products.  
The more stringent r equirements are necessary to achieve the greater level of control 
of emissions needed in California.  
The differences between the proposed California requirements and existing federal 
requirements are intended to lead to the reduc tion of  NO x and ROG  emissio ns and 
replace ment of  the SORE  equipment  fleet with ZEE as soon as feasible so as to 
alleviate the health and environmental burden of SORE emissions, allow California to 
meet the 2016 State SIP Strategy commitments, and help ensure that SORE 
equipment sold and used in California will comply with the exhaust and evaporative 
emission standards over its useful life. The cost of these regulations is justified by their 
benefit to human health and the environment from ensuring SORE meet the emission 
standards .  
These differences are also authorized by State and federal law . CARB may regulate 
emissions from off -road engines under the authority granted to it by the California 
Legislature in the HSC , and under the provisions of the federal Clean Air Act that 
direct EPA to authorize California to regulate emissions from off -road engines. 
The Proposed Amendments requir ing emission standards of zero for SORE  produced 
for sale or lease for use or operation  in California are technologically feasible.  ZEE are 
commercially available, and their use is economically favorable . Increasing adoption of 
ZEE is desirable to help achieve the expected  emission reductions. Furthermore, 
because the population of small off -road equipme nt includes preempt equipment, i.e.,  
farm and construction vehicles and equipment, over which CARB does not have 
regulatory authority, achieving the expected  emission reductions will ultimately 
require replacing SORE equipment that is not preempt with ZEE . Presently, no f ederal 
regulation  for small off -road equipment  incentivizes or requires the adoption of ZEE.   
148 X. Public  Process for  Development of the Proposed Action 
(Pre-Regulatory Information)  
Consistent with Government Code sections 11346, subdivision (b), and 11346.45, 
subdivision (a), and with the Board’s long -standing practice, CARB staff held public 
workshops and other meetings with interested stakeholders during the development 
of the P roposed Amendments . These informal pre- rulemaking discussions p rovided 
staff with useful information that staff  considered during development of the Proposed 
Amendments that are now available for formal public comment.  This chapter describes 
the history of public process that staff conducted in relationship to the dev elopment 
of this rulemaking.  
A. Survey Development and Informational Update to the Board  
Throughout development of the  survey conducted by CSU F (CSUF SSRC,  2019), 
meetings of the SORE Working Group were held to get feedback on the survey questions. The SORE Working Group consists of interested stakeholders, including manufacturers , trade associations, government agencies, individuals, and 
environmental organizations . At each sta ge of the survey, all parties were invited to 
give feedback on the questions asked , and the survey questionnaires were  improved 
as a result.  
1. October 27, 2017, SORE Working Group Meeting  
The SORE Working Group met via conference call  on October 2 7, 2017, to discuss the 
residential survey questionnaire, among other topics. The discussion included an overview of the survey. CARB staff described the phases of the survey, targeted 
numbers of responses, the method of response collection, a nd the samples from which 
potential respondents would be selected. Stakeholders asked questions and provided 
suggestions for modifications to the survey questionnaire during this meeting. CARB staff provided clarifications in response to questions during the meeting. As a result of 
the feedback provided by stakeholders and further discussions, CARB staff worked 
with CSUF staff to ma ke revisions to the residential survey questionnaire. Those 
revisions included:  
• Adding a question to confirm the respondent lived in California  
• Adding a question to confirm the type of phone line (landline or cellular) the respondent was using  
• Modifying a question regarding who maintains the lawn, garden or landscaped areas at the respondent’s home  
• Modifying questions regarding  the frequency of use of a piece of equipment  
• Modifying questions regarding the age of a piece of equipment  
• Modifying questions regarding the amount of time a respondent expected to keep a piece of equipment   
149 • Modifying questions to ask about “engine maintenance” rather than all types of 
“maintenance” 
• Adding a question to assess whether a respondent who planned to purchase 
electric equipment would purchase corded or cordless electric equipment  
• Modifying questions regarding a respondent’s decision to purchase electric or gasoline- powered equipment to avoid leading respondents tow ard any of the 
response options  
• Modifying a question regarding the age of gas cans  
• Modifying a question regarding the frequency of filling gas cans  
• Adding a section to ensure households were not counted more than once in the 
survey and the respondents were representative of the state population  
2. June 8, 2018, SORE Working Group Meeting  
The SORE Working Group discussed  the business survey questionnaire  and updates to 
the residential survey questionnaire, among other topics , during a meeting  via 
conference call on June 8, 2018. The draft business survey questionnaire discussed in the meeting incorporated revisions to the residential survey questionnaire that 
resulted from the October 27, 2017, working group meeting.  CARB provided updates 
on the status of the residential survey and reminded the working group of  the phases 
of the survey, targeted numbers of responses, the method of response collection, and 
the samples from which potential respondents would be selected. Stakeholders asked 
questions and provided suggestions for modifications to the survey questionnaire 
during this meeting. CARB staff provided clarifications in response to questions during the meeting. As a result of the feedback provided by stakeholders and further 
discussions, CARB staff worked with CSUF staff to make revisions to the business 
survey questionnaire.  
3. January 10, 2019, SORE Working Group Meeting  
The SORE Working Group met via conference call on January 10 , 201 9, to discuss the 
landscap er survey questionnaire and updates on the status of the residential and 
business surveys , among other topics. The draft landscaper  survey questionnaire 
discussed in the meeting incorporated revisions to the business survey questionnaire 
that resulted from the June 8, 2018 , working group meeting . CARB staff worked with 
CSUF staff to make revisions to the landscaper  survey questionnaire based on 
feedback and suggestions from  stakeholders.  
4. April 17, 2019, SORE Working Group Meeting 
The SORE Working Group met on April 17, 2019, via conference call. Topics of discussion included MY 2020 certification and testing. CARB staff provided an update 
on the survey and answered questions from stakeholders.   
150 5. November 2018 Informational Update to the Board 
Staff presented an update to the Board during its public hearing in November 2018 
titled , “Informational Update on Reducing Emissions from Small Off -Road Engines: 
Operator Exposure, Health Risks, and Pathways to Zero Emissions.” The staff update 
included information about  demonstration projects that provide  professional 
landscapers an opportunity to use and test professional -grade battery- operated 
landscaping equipment. Additionally, staff provided information on  cities in California 
that had already replaced  their SORE  municipal landscaping  equipment  with ZEE . Staff 
noted that some  colleges and universities in California are also on the path to adopt  
ZEE to replace their SORE equipment . There was a showcase of ZEE outside the 
meeting room with 8 manufacturers and businesses showing their newest ZEE. A 
similar showcase of ZEE was conducted in the November 2016 Board meeting when 
staff proposed amendments to the SORE evaporative regulations.  
B. Public Workshops 
Staff conducted three public workshops  to discuss the development of the Proposed 
Amendments with stakeholders. All the workshops were announced with the issuance 
of a public workshop notice prior to their occurrence. These notices were posted to  
the program’s website and sent out to over 5 ,000 subscribers to the “SORE Working 
Group” and “Mobile Source Program Mailouts” public email list serves. Each of these 
workshops were open to all members of the public. CARB staff made documents and/or presentations available in advance of the meetings/workshops to help 
stakeholders prepare for the discussions.  
The first  workshop  was held on September 26, 2019 , in person at Sacramento, 
California, with an option for remote participation via  webinar. The workshop 
introduced regulatory concepts and a plan to require new  small off -road equipment  to 
be ZEE . Staff also presented the results of a recently completed statewide survey of 
SORE population and activity conducted by CSUF (CSUF SSRC, 2019).  
 
A second workshop was held on  June 9, 2020, via webinar. Draft regulat ory text was 
released in advance of the workshop on May  29, 2020. At this workshop, staff 
presented  a summary of the draft changes to  the regulations . The staff presentation 
was followed by  a lengthy discussion— some  participants  requested rapid 
implementation of  a zero-emission requirement , while others recommended  a slower 
transition to zero -emissions, either for all SORE equipment, or for specific equipment 
types.  
A third workshop was hel d on March 24, 2021, via webinar. Updated draft regulatory 
text, incorporating the changes made since the June 2020 workshop, was posted 
online to facilitate an informed discussion . The workshop presentation included a 
summary of the potential regulatory c hanges , including an updated  timeline for  
implementation of emission standards  of zero and introduction of the  zero- emission 
generator credit program. Feedback was directly requested  on the zero- emission  
151 generator credit program, which would allow manufacturers to offset emissions from 
generators with emission levels above the potential  emission standards by using 
credits earned from certifying zero -emission generators.  An updated timeline for the 
rulemaking process was also presented .  
C. Solicitation of Alternatives  
On November 19, 2019, CARB staff sent an email to the CARB -maintained listserv for 
the SORE Working Group and the Mobile Source Program Mailouts, soliciting 
alternatives to what was presented in the September 2019 workshop.  Appendix J 
includes a copy of the email text. The SORE Working Group list has approximately 
4,000 subscribers , and the Mobile Source Program Mailouts has approximately 5,000  
subscribers, with many overlapping subscribers between the two.  Thirteen replies 
were re ceived, with most responders asking CARB to require zero -emissions as soon 
as possible. The respondents asking CARB to require zero -emissions as soon as 
possible  included the American Lung Association in California, the Clean Air Coalition, 
the Environmental Council of Sacramento, the Sierra Curtis Neighborhood Association, and several individual residents. OPEI, which represents, “more than 100 manufacturers and their suppliers of gas and electric -powered outdoor power 
equipment and utility vehicles” also submitted comments. OPEI’s comments  offered 
no regulatory alternative, but said, “OPEI estimates that the SORE sector emissions inventory levels will fall through 2031. As a result, OPEI suggests the SIPs original SORE reduction goals may be met without an y new or additional regulations.” No 
data w ere provided to support  this assertion.  
D. Stakeholder Meetings 
During the rulemaking process, s taff held numerous meeting s with stakeholders. Staff 
met with OPEI, Truck and Engine Manufacturers Association ( EMA ), and Air 
Improvement Re source, Inc. on January 8, 2019, to discuss emissions from SORE and 
emission reduction goals. Included in material presented to CARB staff by OPEI and EMA was  the meeting objective, “Establish the foundation for the cooperative and 
open-minded industry / agency relationship necessary for California to achieve its 
goals.” On March 4, 2019, OPEI presented at the Outdoor Power Equipment and Engine Service Association meeting in Miami, Florida. Included in a slide that discussed OPEI’s 2019 priorities was, “Establish public record counter to CA emissions rulemaking.” (OPEI,  2019).  
Shortly after the workshop in September 2019, staff met with EMA , Honda,  and Briggs 
& Stratton to discuss the potential proposals. Staff also met with the Clean Air 
Coalition. Honda and Stihl met separately with staff in January 2020 to discuss the rulemaking. In January 2020, staff also met with Greenworks to discuss zero -emission 
riding mowers and a potential credit program.  
In February 2020, staff met with staf f from the office of Supervisor Katie Rice in Marin 
County to discuss potential SORE rulemaking. S taff briefed staff members from the  
152 State Legislature about SORE and possible rulemaking approaches  that were 
discussed in the public workshops. Manufacturers  of Emission Controls Association 
(MECA) also met with staff to discuss SORE emission control technologies and their 
potential. Finally, staff met with Onyx Solutions, who make propane engines and conversion kits, to discuss the SORE regulations. 
In March 2020, staff met with the American Green Zone Alliance ( AGZA) to talk about 
adoption of  ZEE in place of SORE equipment  and training for landscapers. The Clean 
Air Coalition and other environmental organization s met with staff in May 2020 to 
discuss the rulemaking. After the workshop in June 2020, staff met with Deniz Bolbol to discuss potential 
regulations and Bolbol’s efforts to have his community adopt zero-emission lawn and 
garden equipment. Honda also met with CARB staff to discuss the workshop and their 
suggestions for CARB’s regulatory approach. In July 2020, staff met with MECA to discuss the draft proposal . Staff also met with the RV Industry Associatio n and OPEI 
separately in August 2020 about the potential rulemaking and the June workshop.  
In October 2020, staff met with Onyx Power who produce zero -emission generators. 
The state of zero -emission generators and their future potential were discussed. In 
November 2020, staff met with Wacker Neuson who make both  SORE equipment  and 
ZEE. Their equipment and goals were discussed.  
Staff members from the State Legislature  were  again briefed in February 2021 about 
SORE and the rulemaking  proposal discussed in pub lic workshops .  
Following the March 2021 workshop, staff met with other stakeholder groups. The 
Sacramento area organization , Mow Better, was briefed on the rulemaking workshop. 
Westerbeke and the National Marine Manufacturers Association met with staff ab out 
marine generators. MECA  also met with staff to discuss the draft proposal.  
E. Stakeholder Outreach 
To encourage  faster adoption  of ZEE, in October 2018  CARB began the ZEE  
Roadshow that showcases professional -grade , battery- powered landscaping 
equipment  from eight manufacturers . A CARB trailer was  designed to transport the 
ZEE Roadshow to interested parties such as schools, colleges, state agencies, 
municipalities, and landscapers who would then try out the electric equipment for a 
predetermined period . To date, 20 entities have been able to use and evaluate the 
professional -grade landscaping equipment.  After hosting the ZEE Roadshow, several 
of the participants have purchased ZEE. Of the 7 participants who have responded to 
inquiries, 4 have already purchased ZEE, and 2 have plans to purchase. One 
participant has purchased over 800 pieces of ZEE.  
The City of Ojai held events related to its replacement of its engine -powered 
municipal landscaping equipment with ZEE. The city received funding for ZEE from th e  
153 Ventura County Air Pollution Control District. CARB staff attended a “ribbon -cutting” 
ceremony in August 2018 where city staff and elected officials  highlighted the benefits 
of ZEE for the community. The city grounds crew showcased the equipment. Staff 
attended a celebration marking the one- year anniversary of the acquisition of ZEE for 
the city in April 2019. In December 2019, CARB staff attended a ceremony in which 
the SORE equipment that had been replaced with ZEE was destroyed and recycled. 
CARB staff  spoke at each of these events, congratulating Ojai on its leadership in 
setting an example that ZEE can be used for municipal grounds keeping and 
landscaping work and discussing the benefits of ZEE for operators and others.  Ojai 
built on the success of it s use of ZEE for municipal landscaping work and adopted 
municipal regulations in April 2020 that prohibit the use of leaf blowers, nonriding lawn mowers, string trimmers, hedge trimmers, lawn edgers, pole hedge trimmers, and pole saws powered by internal c ombustion engines anywhere within the city.  
CARB staff has attended four  conventions held for landscapers in California . These 
conventions have provided opportunities for staff to inform  professional landscapers 
about upcoming regulation changes and about ZEE  capabilities and availability . Events 
attended include the Green Schools Summit in Pasadena in November 2018, California Landscape Industry Show in Ontario in February of 2019, Long Beach Landscape Expo 
in October 2019, and the NorCal Landscape Show in February of 2020.  
CARB staff has presented information about zero -emission landscaping equipment 
and the potential for regulatory amendments aimed at transitioning from SORE  
equipment  to ZEE  at several meetings attended by landscapers and local 
decision-m akers in California. Presentations were given to the Pleasanton Committee 
on Energy and the Environment in January 2019, the San Francisco Integrated Pest 
Management Technical Advisory Committee in March 2019, the San Mateo Integrated Pest Management Workshop in April 2019, the San Francisco Commission on the 
Environment in November 2019, and the Tri Valley Air Quality Community Alliance in 
April 2021. 
XI. The Specific  Purpose and Rationale of Each Adoption, Amendment, 
or Repeal  
This chapter provides the specific purpose of each proposed amendment and the 
rationale for CARB staff’s determination of why the P roposed Amendments are 
reasonably necessary to carry out the purpose of the provisions of law they are 
implementing and to address the problems described  in Chapter II. Appendices A  
through G  of this Staff Report provide the full text of the P roposed Amendments 
shown in strikeout and underline formatting.   
154 A. Exhaust Emission Regulations  
This section provides a summary, purpose, and rationale for each Proposed 
Amendment to CCR  Title 13, Division 3, Chapter 9 §§ 2401 through 2408.2. 
Appendix  A of this Staff Report provides the full proposed regulatory language of 
these sections.  
Global Amendments throughout the Exhaust Emission Regulations  
The following proposed global changes provide updated and clarifying text that does 
not alter current requirements for SORE equipment.  
Acronym Change  
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before  “Air Resources Board ,” for consistency with recent CARB 
document style practices designed to improve clarity. 
Rationale . This change reflects the California Air Resources Board’s recent change to, 
and preferred use of, the acronym “CARB” versus the prior acronym, “ARB,” and th e 
entire agency title, “California Air Resources Board.”  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents accessible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines.  
Division Name Change and Address Change 
Purpose. The Proposed Amendments change “ Emissions Compliance, Automotive 
Regulations and Science Division” to “ Emissions Certification and Compliance 
Division, ” and change “Off -Road Certification/Audit  Section” to “Off -Road Spark -
Ignited Engine Certification Section,” throughout the exhaust emission regul ations 
because of the reorganization of divisions within CARB.  In addition, the Proposed 
Amendments change “ 9528 Telstar Avenue, El Monte, California 91731” to 
“4001 Iowa Street, Riverside, CA 92507” to reflect the address of CARB’s new 
Southern California  headquarters.  
Rationale . These change s are necessary because CARB divisions have been 
reorganized  and renamed, and construction of the new Southern California 
headquarters has been completed. The Off-Road Spark -Ignited Engine Certification 
Section  within the Emissions Certification and Compliance Division  now has 
responsibility for reviewing certification applications, so the division and section name s  
155 have been updated.  Division staff and the vehicle emissions testing  laboratories will be 
housed at the new headquarters.  
Description of When Reports Are Submitted  
Purpose. Throughout the regulations, the Proposed Amendments change notations of 
“within XX days of” to “within XX days after” to increase clarity regarding the deadline 
by which documents must be s ubmitted.  
Rationale . Certification holders are required to demonstrate compliance with new 
engine compliance and production line testing provisions and credit provisions after the end of each calendar quarter under § 2407, and to submit reports on sales af ter 
the model year has ended  under §§ 2408 and 2408.1. Changing “of” to “after” better 
describes when reports are due and clarifies that these reports should have complete 
information from the entire calendar quarter or model year.  
“Family Emission Level”  Term Usage  
Purpose. The Proposed Amendments change the term “Family Emission Limit” to 
“Family Emission Level” to restore consistency of term usage throughout the exhaust 
emission regulations. The Proposed Amendments include this change in the following 
sections: 2404(l)(1), 2408(b)(5), 2408(f)(1), 2408(h)(1)(B), 2408.1(b)(4), and 
2408.1(h)(1)(B).  
Rationale . These proposed changes are necessary to prevent confusion for 
manufacturers and other readers and do not affect SORE emission standards nor 
testing requirements. The California SORE regulations traditionally use the term 
“Family Emission Level” while the federal regulations for small nonroad spark -ignition 
engines use the term “Family Emission Limit.” The term “Family Emission Limit” has inadvertently been used interchangeably with “Family Emission Level” because their 
definitions are virtually identical:   
• Per Title  13, California Code of Regulations, § 2401(a): “ “Family emission level” 
or “FEL” means an emission level that is declared by the manufactur er to serve 
for the averaging, banking, and trading program and in lieu of an emission 
standard for certification. The FEL serves as the engine family’s emission standard for emissions compliance efforts. If the manufacturer does not declare 
an FEL for an engine family, the applicable emissions standard must be treated 
as that engine family’s FEL for the purposes of any provision of this Article. ” 
• Per California Part 1054.801:  “Family emission limit (FEL)  means an emission 
level declared by the manufacturer that will be used in the ABT program. The 
family emission level will take the place of an otherwise applicable emission standard. The family emission limit must be expressed to the same number of decimal places as the emission standard it replaces. The fa mily emission limit 
serves as the emission standard for the engine family (exhaust) or emission family (evaporative) with respect to all required testing. ”  
156 • Per federal Part 1054.801: “ Family emission limit (FEL)  means an emission level 
declared by the manu facturer to serve in place of an otherwise applicable 
emission standard under the ABT program in subpart H of this part. The family 
emission limit must be expressed to the same number of decimal places as the 
emission standard it replaces. The family emission limit serves as the emission 
standard for the engine family (exhaust) or emission family (evaporative) with respect to all required testing. ” 
The proposed changes to provide consistent use of the term “Family Emission Level” 
satisfy clarity requirements under  California regulations (Title  1, CCR, § 16(a)(4)).  
§ 2401. Definitions  
§ 2401(a)(12)  
Purpose. The current regulations in § 2401(a)(12) define the meaning and calculation 
of “deterioration factor” and identify the procedures required for its determination as “Part II, Section 3 of the 1995- 2004 Test Procedures, and Subpart B, Section 90.104 of 
the 2005 and Later Test Procedures.” The Proposed Amendments replace the text “2005 and later” with “2005- 2012” to reflect the applicability of Part 90 test 
procedures to MYs  2005 through 2012. To identify the required procedure for 
MY 2013 and subsequent model years, the Proposed Amendments add the text “or 
Subpart C, section 1054.245 of the “California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine -Testing 
Procedures (Part 1054),” adopted October 25, 2012, and amended [insert amended date] , as applicable .” The Proposed Amendments include a placeholder for the 
amended date, “ [insert  amended date] ”, that will be updated to reflect the CARB 
adoption date of the Proposed Amendments.  
Rationale. This change is necessary to update the definition for consistency with 
existing and proposed changes to other SORE regulations. Part II, Section 3 of the 
1995- 2004 Test Procedures and Subpart B of the 2005- 2012 Test Procedures were 
used for earlier model years. The “California Exhaust Emission Standards and Test 
Procedures for New 2013 and Later Small Off -Road Engines; Engine -Testing 
Procedures (Part 1054),” is the updated test procedures that has been used for 
MY 2013 and subsequent engines. Referencing these test procedures in the exhaust 
regulations is necessary to clarify which procedures to use for determining 
deterioration factors. This change  does not alter current requirements for SORE 
equipment.  
§ 2401(a)(15)  
Purpose. The current regulations in § 2401(a)(15) define the meaning of “emissions 
durability period” and provide multiple references from which to select a durability period, including  a reference to a table in §  2403(b) of the exhaust regulations. T he 
Proposed Amendments remove the references to “Part II, Section 1 of the 1995- 2004  
157 Test Procedures and Subpart  B, Section 90.104 of the 2005 and Later Test 
Procedures” and leave only the reference to the table in § 2403(b) because the 
emissions durability periods are listed in the table in § 2403(b).  
Rationale . This change is neces sary to clarify and simplify the definition and to reduce 
the potential for confusion and conflicting instructions.  The 1995- 2004 and 2005- 2012 
Test Procedures were used for earlier model years and have not been used for 
MY 2013 and later model year engines. The reference to “2005 and Later Test 
Procedures” was outdated; the title of those procedures was updated in amendments 
adopted by CARB in 2011, but the reference in this definition was not updated at that time. This change does not alter current requirements for SORE equipment.  
§ 2401(a)(19) [newly proposed definition]  
Purpose. The  Proposed Amendments add a new  definition for “Engine” to clarify what 
qualifies as an engine. The definition specifies that “ Engine” means a complete, 
operational engine , and  that any engine block or kit with the parts necessary to 
assemble an engine block with or without an installed crankshaft is also considered an 
engine. The definition specifically excludes gas turbine engines .  
Rationale . The term engine was not defined in past regulations, which led to the sale 
of complete sets of “replacement parts.” The parts in these kits appear to be 
aftermarket and counterfeit rather than original equipment manufacturer replacement 
parts. The parts can be assembled into a working eng ine that is not certified or 
compliant with the applicable emission standards. The newly proposed definition of 
“engine” is necessary to prevent circumvention of regulation requirements.  
§ 2401(a)(19) [renumbered to (20)]  
Purpose. The current regulations d efine “engine family” as  a subclass of a basic engine 
based on similar emission characteristics  and specifies that the engine family is the 
groupings of engine that is used for the purposes of certification. The Proposed 
Amendments add text to the definition to include “ zero- emission small off -road 
equipment ” in the definition. “Zero -emission small off -road equipment” has the same 
meaning as “zero -emission equipment” or “ZEE” for the purposes of the SORE 
regulations and this Staff Report.  
Rationale . The cha nge is necessary to provide clarity and consistency with §  2400(a)(4), 
which states, “ This article may apply to zero -emission small off -road equipment. ” In 
addition, existing requirements in § 2408.1 and many of the Proposed Amendments to the exhaust emission regulations explicitly or implicitly refer to ZEE. Adding ZEE to the definition of engine family will help prevent confusion for readers.  
§§ 2401(a)(19) through (53)  
Purpose. The Proposed Amendments add seven new definitions to § 2401(a). The 
newly proposed  definitions are numbered 19, 29, 30, 32, 36, 58, and 59 so that they  
158 are in alphabetical order with the previously included definitions. Consequently, the 
Proposed Amendments also renumber the definitions that were previously included in 
this sectio n so that all definitions in this section are in alphabetical order and 
sequentially numbered.  
Rationale . These changes are necessary to maintain a correctly numbered, alphabetical 
list of definitions and to prevent confusion for the reader.  
§§ 2401(a)(29) and (30) [newly proposed definitions]  
Purpose. The Proposed Amendments add definitions for “generator” (as § 2401(a)(29)) 
and “generator engine” (as § 2401(a)(30)) to specify that “generator” means off -road 
equipment that excl usively produces electric power, and “generator engine” means 
an engine installed exclusively in a generator.  
Rationale . These changes are necessary to provide clarity and regulatory certainty 
because the Proposed Amendments to § 2403 include exhaust emission standards for 
generato r engines that differ from emission standards for engines in other types of 
small off -road equipment. In addition, the Proposed Amendments specify a new, 
generator -specific exhaust emission reduction credit program in a new 2408.2 section. 
Failure to specify definitions of the terms generator and generator engine in the 
exhaust emission regulations could result in noncompliant equipment being introduced for sale or lease for use in California, or inappropriate credit generation 
calculations and credit use. Regulatory definitions for these terms are necessary to 
ensure no excess emissions result from improper implementation of the proposed emission standards or credit program. Furthermore, the regulatory definitions help provide a fair and equitable process f or all manufacturers that choose to apply for 
certification under the new emission standards or participate in the credit program.  
§ 2401(a)(32) [newly proposed definition]  
Purpose. The Proposed Amendments add a definition for the term “Handheld” to 
speci fy what types of equipment are considered to be handheld equipment. The 
proposed definition specifies that “handheld” means relating to off -road equipment 
using an engine with displacement less than or equal to 80 cc that meets either of the following crit eria: (A) It is carried by the operator throughout the performance of the 
manufacturer’s intended function. (B) It has a combined engine and equipment dry weight under 16.0 kilograms, has no more than one wheel, and the operator provides 
support or attitud inal control for the equipment throughout the performance of the 
manufacturer’s intended function. Support means to hold a piece of equipment in 
position to prevent it from falling, slipping, or sinking, without carrying it. Attitudinal control involves re gulating the horizontal or vertical position of the equipment.  
Rationale . This change is necessary to provide clarity and regulatory certainty because 
handheld equipment generally has less stringent requirements under the current regulations than other sma ll off-road equipment. Nonhandheld equipment such as  
159 generators and pressure washers can meet more stringent requirements because it is 
not carried or continuously supported by operators during use. Failure to define the 
term “handheld” in the exhaust emission regulations could result in noncompliant 
equipment being introduced for sale or lease for use in California, or inappropriate credit calculation and credit use for manufacturers that participate in the exhaust emission reduction credit program. A regulatory definition with clear criteria is 
necessary to ensure no excess emissions result from improper implementation of the 
emission standards or credit program. Furthermore, a regulatory definition helps provide a fair and equitable process for all manufa cturers that choose to apply for 
certification under the new emission standards or participate in the credit program.  
§ 2401(a)(31) [renumbered to (35)]  
Purpose. The current regulations specify that “model year” means the manufacturer’s 
annual production p eriod that includes January 1 of a calendar year or, if the 
manufacturer has no annual production period, the calendar year. The Proposed Amendments add text that further specifies the allowable date range for any model 
year. The Proposed Amendments specif y that the model year may not begin before 
January 2 of the prior calendar year or extend beyond December 31 of the named 
model year.  
Rationale . This change clarifies existing requirements and is necessary to provide 
consistency and regulatory certainty be cause manufacturer -named model years may 
have annual production periods that extend beyond a given calendar year. For a manufacturer whose annual production period does not coincide with the calendar year, clarifying that the model year may not begin before January 2 of the prior 
calendar year or extend beyond December 31 of the named model year  better 
ensures that no reader would misinterpret the definition of “model year.”  
§ 2401(a)(36) [newly proposed definition]  
Purpose. The Proposed Amendments add a d efinition for the term “NEMA  5-15” to 
specify that it means a receptacle that complies with  the industry standard for 
NEMA  5-15 as established in ANSI/NEMA WD 6- 2016 ( February 11, 2016) , and 
incorporates ANSI/NEMA WD 6 -2016 by reference.   
Rationale . This definition is necessary to provide clarity for a requirement included in 
the Proposed Amendments for the new Zero -Emission Generator Credits Averaging, 
Banking, and Trading Provisions  in the new 2408.2 section. The proposed 
§ 2408.2(b)(4)(D)(1)a. sp ecifies, “A zero- emission generator must have a device 
capable of providing 120 -Volt nominal alternating current power as well as at least one 
NEMA 5 -15 receptacle. ” NEMA 5 -15 is a commonly used industry standard for 
household electrical receptacles. Adding this definition with the incorporated 
reference for ANSI/NEMA WD 6 -2016 will prevent ambiguity when determining 
whether certain equipment can qualify for zero -emission generator credits.   
160 § 2401(a)(58) and (59) [newly proposed definitions]  
Purpose. The Proposed Amendments add definitions for “zero -emission generator” 
(as § 2401(a)(58)) and “z ero-emission generator credits” (as §  2401(a)(59)). The 
proposed definition specifies that “zero -emission generator” means any small off -road 
equipment that generates or stores energy and distributes electrical power while 
producing zero emissions of any criteria pollutant (or precursor pollutant) under any and all possible operational modes and conditions.  The proposed definition specifies 
that “zero -emission generat or credits” means  the amount of emission reductions 
generated by using zero -emission generators in place of small spark -ignition off -road 
equipment , and that ze ro-emission generator credits are calculated pursuant to 
§ 2408.2 and approved by CARB.  
Rational e. This change is necessary to provide clarity and regulatory certainty because 
the Proposed Amendments specify a new, generator -specific exhaust emission 
reduction credit program in a new 2408.2 section. This voluntary program would allow manufacturers to  offset emissions from generators with emission levels above the 
proposed emission standards by using credits generated by zero -emission generators. 
The goal of the proposed credit program is to incentivize manufacturers to increase development and product ion of zero- emission generators, particularly zero -emission 
generators with the greatest energy storage and highest power output. Such incentive 
is needed to increase the availability and reduce the cost of zero -emission generators. 
Failure to specify definitions of the terms “zero -emission generator” and “z ero-
emission generator credits” could result in inappropriate credit generation calculations 
and credit use. Regulatory definitions for these terms are necessary to ensure no 
excess emissions result from  improper implementation of the credit program, and to 
help achieve the goal of the proposed credit program, which is to  increase 
development and production of zero -emission generators. Furthermore, the 
regulatory definitions help provide a fair and equita ble process for all manufacturers 
that choose to participate in the credit program.  
§ 2403. Exhaust Emission Standa rds and Test Procedures – Small Off-Road 
Engines  
§ 2403(b)(1)  
Purpose. The current regulations in § 2403(b)(1)  specify the exhaust emission 
standards for HC + NO x, CO, and PM emissions from SORE, by displacement  
category, produced on and after the model years specified in a multi -part table in that 
section. For the emission standards applied to model year ranges that do not have an end date (e.g., “2005 and subsequent”), the Proposed Amendments replace the “and 
subsequent” text with “through 2023” to limit the applicability of all current emission 
standards to engines manufactured  through MY 2023.  The headings for PM emission 
standards currently read “Particulate.” The Proposed Amendments change these to 
“Particulate Matter.” In addition, the Proposed Amendments expand the current table 
to apply new, more stringent exhaust emission standards for MY  2024 and subsequent  
161 model years. The purpose of the proposed emission standards is to further reduce 
SORE emissions in order to improve air quality in California.  
The proposed  new exhaust  emission standards  for MY 2024 and subsequent  model  
years  differ  from  the current standards  in the following ways:   
• First, the  Proposed Amendments provide two new table sections for the 
proposed emission standards, one for standards for all SORE except generator 
engines, and the second for standards for generator engines. In contrast, the current regulations have one set of emission standards for engines used in all SORE equipment. The Proposed Amendments provide a separate table section for generator engine emission standards to indicate with as much clarity as 
possible for readers that generator engines have requirements different from 
other SORE for MY 2024 and subsequent model years.  
• Second, the Proposed Amendments would set HC + NO
x and PM emission 
standards to zero for all SORE, except generator engines, beginning in 
MY 2024, and for generator engines beginning in MY  2028. The purpose of 
setting these emission standards to zero is to accelerate the adoption of ZEE to 
replace SORE equipment and to achieve the maximum degree of technologically feasible, cost -effective emission reductions from SORE by the 
earliest practicable date. Chapter VIII and Appendix I de scribe  other 
alternatives  considered and provide CARB staff ’s analyses that support the 
conclusion that the se Proposed Amendments would enable the most cost -
effective emission reductions from SORE.  When the HC + NO
x and PM emission 
standards of zero become effective, exhaust emission reduction credits could be used to offset any HC  + NO
x and PM emissions from SORE manufactured for 
sale or lease for use in California. Sections 2408 and  2408.1  contain the current 
regulations f or the voluntary exhaust emission reduction credit programs, and, 
as described later in this chapter, the Proposed Amendments include revisions to those credit programs to further incentivize manufacturers to accelerate their development and production of zero- emission generators and other ZEE.  
• Third, for generator engines in MYs 2024 through 2027,  the Proposed 
Amendments set HC  + NO
x and PM emission standards that are approximately 
40 to 90 percent more stringent  than current emission standards, depending  on 
the engine displacement category. The purpose of these interim emission 
standards for generator engines is to require further emission reductions from 
generator engines, while at the same time, allow more time  to implement the 
proposed emission standards of zero for generator engines.  
• Fourth, the Proposed Amendments establish CO emission standard s of 
4.5 g·kWh-1 for marine generator engines. The Proposed Amendments establish 
a CO emission standard of 20.6 g·kWh-1 for all engines with displacement 
greate r than 825 cc, except marine generator engines. The Proposed 
Amendments also establish two new CO emission standards for generator 
engines other than marine generator engines for the MY  2024 and subsequent  
162 model years, with displacement  less than or equal to 825 cc: a standard of 
400 g·kWh-1 for generator engines with displacement less than 225  cc; and a 
standard of 200 g·kWh-1 for generator engines with displacements between 
225 cc and 825  cc, inclusive. The proposed CO emission standards for all other 
SORE with displacement less than or equal to 825 cc —536  or 549 g·kWh-1, 
depending on the displacement category —are  the same as current emission 
standards for recent model year SORE . 
• Fifth, the Proposed Amendments add a new category in both table sections f or 
engines with displacement greater than 825  cc to align the SORE exhaust 
emission standards  with the current exhaust emission standard s for large spark -
ignition engines ( i.e., engines rated greater than 19 kilowatt s), which have 
different emission standards for engines with displacement greater than 825 cc 
than for those with displacement less than or equal to 825 cc . The delineation 
of the four smaller displacement categories remains the same: < 50 cc; 
50-80 cc, inclusive; > 80 cc - < 225 cc; and 225- 825 cc, inclusive.  
• Sixth, the Proposed Amendments update the emissions durability period values 
in both tables for MY  2024 and subsequent model years. As currently defined 
by § 2401(a)(15), the “ emissions  durability period” is the period that represents 
an engine’s useful life. The durability period is used to determine an engine 
family’s deterioration factors and in the calculation of certification emission 
reduction credits.  The current regulations allow applicants for certification to 
select a durability pe riod for their engines from a range of choices that 
generally reflect “moderate,” “intermediate,” or “extended,” use. The Proposed Amendments would lengthen the emissions durability periods for 
some engines to more accurately reflect the actual lifetime of  SORE equipment, 
and would allow only one option per displacement category. This would 
prevent manufacturers from certifying to unrealistically short emissions durability periods and only meeting the emission standards for a small portion of the equipment’ s lifetime.  
Rationale . These changes are necessary to achieve the maximum degree of 
technologically feasible, cost -effective emission reductions from SORE by the earliest 
practical date, as required by state law. The Proposed Amendments to the  exhaust 
emission standards, along with the Proposed Amendments to the evaporative 
emission standards in § 2754(a) (described in section B of this chapter), are necessary 
to achieve emission reductions expected under the 2016 State SIP Strategy. In 
addition, these changes are a necessary component of the strategy to a chieve 
100 percent zero -emission from off -road vehicles and equipment  operations in the 
State by 2035, as ordered in EO N -79-20. 
As described in section C.2 of Chapter  I of this Staff Report, current SORE r egulations 
will not achieve emission reductions expected under the 2016 State SIP Strategy. The 2016 State SIP Strategy calls for more stringent emission standards and additional 
incentives to accelerate the deployment of ZEE  to prevent SORE emissions from   
163 increasing and ultimately to achieve emission reductions necessary to attain ambient 
air quality standards for ozone by 2031 and protect the health and welfare of all 
California resident s. As described in section B of Chapter  III, SORE emissions 
modelling results indicate implementation of the proposed exhaust and evaporative 
emission standards would result in emission reductions that would fulfill the 2016 State 
SIP Strategy commitments to reduce statewide SORE emissions of ROG by 36 tpd  and 
NO x by 4 tpd  in 2031, as well as emission reduction commitments specific to the South 
Coast and San Joaquin Valley air basins.  
New emission standards for all SORE would apply beginning with MY 2024 to provide the lead time required by the f ederal Clean Air Act § 209 in U.S. Code §  7543. That 
section requires that, “California … adopt such standards at least 2 years before commencement of the period for which the standards take effect.” The two -year lead 
time provides manufacturers with lead time to develop and manufact ure equipment to 
meet the new emission standards in the Proposed Amendments. Implementing 
emission standards at the earliest date would result in greater emission reductions and 
further progress in meeting EO  N-79-20. 
The Proposed  Amendments allow more  time for generators  to meet  emission  
standards  of zero by setting  the exhaust  HC + NO
x and PM emission standards  for 
generator  engines to zero for MY 2028 rather than MY 2024  as is done  for engines in 
other  SORE  equipment.  This is necessary  for two reasons: 
• While zero -emission generators are available to meet users’ demand, there is 
still a need to allow manufacturers more time to continue to innovate and grow 
to meet the future demands of the zero -emission generator market. The 
fraction of all generators currently in use that are ZEE is significantly lower than 
that for lawn and garden equipment, such as lawn mowers and trimmers.  
• One of the main uses of generators is backup power supply. Some people 
depend on generators for power backup during outages. The longer time for 
generators to meet emission standards of zero will allow for these people to 
identify suitable power backup options.  
As a result, the Proposed Amendments include generator -specific exhaust emission 
standards in § 2403(b) , and evaporative emission standards in § 2754(a) , for the 
MYs 2024- 2027 period that are more stringent and comprehensive than the current 
emission standards, but are not zero. These proposed emission standards will enable 
emission reductions to be achieved while allowing m ore time for manufacturers to 
develop additional options for zero- emission generators. Section D.3.b in Chapter  I 
provides additional information that supports the rationale for the necessity to allow 
more time to for generators to meet emission standards of zero. It is important to note 
that the SORE regulations do not apply to stationary generators, which are not moved for equipment operation or storage. These stationary generators are frequently powered by natural gas or propane and usually installed on a concrete pad. To the 
extent that Californians rely on generators subject to CARB’s SORE regulations, the  
164 time between the Board adoption of the Proposed Amendments and the MY  2028 
effective date of the emission standards of zero will provide adequate tim e for 
manufacturers to assess power outages in California, better understand consumer 
needs during these outages, and develop zero -emission generators to better meet 
those needs.   
The selection of a MY 2028 effective date for the emission standards of zero  for 
generator engines is based on, and balances, multiple factors. Manufacturers informed CARB staff following the June 2020 public workshop that an interim period of two 
years for the lower emission standards would not allow time for sufficient sales of 
generators certified t o the  more stringent emission  standards to make back their 
investment to design, certify and produce the lower -emitting generators.  
At the same time, the existing exhaust and evaporative emission reduction credit programs described in  § 2408, §  2408.1,  and §  2754.1, and the proposed expansion of 
the voluntary credit programs to incentivize additional production of zero -emission 
generators (newly proposed §§ 2408.2 and 2754.3 in this section A in this chapter), are 
expected to provide compliance flexibility for manufacturers. Under the current regulations and Proposed Amendments, manufacturers may continue to generate emission reduction credits through MY  2027 through the averaging, banking, and 
trading programs to offset generator emiss ions beyond MY  2027 (up to five years after 
credit generation). This flexibility could make it cost- effective for the manufacturers 
that are able and choose to participate in the programs to sell their new lower -
emitting generators for a longer period, or even to proceed directly to the design and 
production of zero- emission generators.  
Finally, an effective date later than MY  2028 would confound the primary goal of the 
Proposed Amendments: Accelerate the adoption of ZEE in place of SORE equipment 
to achieve the necessary SORE emission reductions by 2031 as expected under the 
2016 State SIP Strategy , and to meet obligations under California EO  N-79-20. The 
2016 State SIP Strategy and EO  N-79-20 are designed to achieve the maximum cost -
effective emission red uctions by the earliest practical date, as required by state law, 
and to meet obligations under the Clean Air Act, all of which are designed to achieve 
emission reductions necessary to attain ambient air quality standards for ozone by 
2031 and protect the health and welfare of all California resident s. The emission 
modelling described in Chapter  III of this Staff Report takes into account both the 
proposed effective dates of the emission standards of zero for generators and other 
SORE equipment, and the potential use of banked credits that could delay the full 
benefit of the emission standards.  
Available information indicates that all of the newly proposed emission standards for SORE in § 2403(b)(1)  and §  2754(a) —emission standards of zero for all SORE exhaust 
and evaporative emissions, and the MY  2024 -2027 exhaust and evaporative emission 
standards for generator engines— are technologically feasible and cost -effective as 
explained below .   
165 Emission standards of zero for exhaust HC + NO x, PM, and evaporati ve emissions: 
Emission standards of zero for SORE have been demonstrated to be feasible as 
evidenced by equipment currently certified for sale or lease for use in California. 
Approximately 52 percent of small off -road equipment in use in California are ZEE  
(CSUF SSRC, 2019). CARB staff’s economic analysis found that consumers could experience net savings with ZEE compared to SORE with certain equipment types, 
and some would experience savings as soon as one year after ZEE purchase. The 
Proposed Amendments would yield statewide cost -savings beginning in 2037 when 
the savings in fuel purchases and maintenance costs become greater than the increased upfront cost to purchase ZEE. In addition, public health benefits would yield 
a cost -savings of $8.82 billion sta tewide over the regulatory time -horizon of 2023 
through 2043. Sections I.E, II.A, IV.B through IV.D, and Appendix I, in this Staff Report 
provide the supporting documentation for these findings.  
MY 2024- 2027 generator- specific standards for exhaust HC + NO
x, CO,  and PM 
emissions and evaporative emissions: These generator -specific emission standards are 
based on engines already certified for sale or lease for use in California  
(CARB,  2021ggg), which indicates they are both technologically feasible and cost -
effective . In each displacement category, except greater than 825  cc, several SORE 
engine families are certified at or below the proposed emission standards, including at least one SORE engine family used in generators. The proposed emission standard s 
and emissions durability period for engines with displacement greater than 825 cc are aligned with the emission standard s and emissions durability period for model year 
2015 and subsequent large spark -ignition engines, i.e., those rated greater  than 19 kW 
and with displacement greater than 825 cc, as established in §  2433 (b). In  addition to 
the generator engines that already meet these emission standards, CARB staff expects that other equipment engines that meet the standards could be adapted for 
generators, whic h would further decrease the cost of compliant generators. It is also 
possible that some of those engine families that meet the proposed emission 
standards are already installed in generators although the manufacturers may not declare such use of the engines in their certification applications.  
                                            
gg CARB staff compiled and evaluated certification data for HC + NO x, CO, and evaporative emissions. 
Ten MY 2020 engine families have HC + NO x certification test emissions lower than the MY 2024 -2027 
generator engine emission levels with credit use listed in Table III -2 and are certified to the longest of 
the current emissions durability periods (ranging from 300 to 1,000 hours, depending on displacement 
category). Of those ten engine families, eight  also have CO certification test emissions lower than the 
proposed MY 2024- 2027 generator engine emission standards listed in Table IX- 3. Nine MY 2020 
evaporative families have hot soak plus diurnal certification test emissions lower than the MY 2024- 2027 
generator engine emission levels with credit use listed in Table III -3. The data are available in the 
following document:  
CARB. 2021g. Technical Support Document: Compilation and Evaluation of Small Off- Road Engine 
Certification Data. Microsoft Excel work book  prepared by staff of the Monitoring and Laboratory 
Division. October 2021.   
166 Carbon monoxide emission standards: Similarly, the proposed new CO  emission 
standards for generator engines (except for marine generator engines) and other 
engines with displacement greater than 825  cc are aligned with the current emission 
standards  for large spark -ignition engines with displacement greater than 825  cc, as 
established in § 2433(b). The proposed new CO  emission standards for generators 
with displacement less than or equal to 825  cc are based on engines already certified 
for sale or lease for  in California . The proposed new CO  emission standards for marine 
generator engines are aligned with the CO  emission standards for marine generator 
engines set by U.S.  EPA in Title 40, Code of Federal Regulations, § 1054.145(n)(2). The 
emission standards set by U.S. EPA have applied since MY 2013 for engine families tested with California’s LEV III certification gasoline. It is necessary to adopt these CO 
emission standards for marine generator engines to ensure CAR B’s emission standards 
for these engines are at least as stringent as U.S.  EPA’s. CARB staff expects that 
adopting these emission standards for marine generator engines will not impose new 
requirements on manufacturers because they already have to certify to these emission 
standards when using LEV III certification gasoline.  
New displacement category: The Proposed Amendments add a new category for 
engines with displacement greater than 825  cc to align the SORE exhaust emission 
standards  with the current exhaust emission standard s for large spark -ignition (LSI) 
engines ( i.e., engines rated greater than 19  kilowatt s) with displacement greater than 
825 cc. In the current regulations, these larger displacement engines are included in 
the “ ≥ 225 cc” displacement category. The proposed change to specify a separate 
category for the large engines is necessary to ensure that SORE with displacement greater than 825 cc are not subject to less stringent emission standards than LSI engines with displacement greater than 825 cc. Some SORE and LSI engines have similar designs and are tuned differently to produce different amounts of power, with 
those producing 19 kW or less meeting the definition of SORE and those producing 
more than 19 kW meeting the definition of LSI engines. Having less stringent emission standards for SORE than for LSI engines may have incentivized the production of large -displacement SORE rather than LSI engines for some applications since 
MY 2015. Aligning the emission standards will ensure the greatest  emission reductions 
because SORE with displacement greater than 825 cc will meet emission standards that have been met by similar LSI engines.  
Emissions durability periods : The proposed new emissions durability periods are also 
based on engines already certified for sale or lease for use in California. The proposed durability period for all SORE with displacement less than or equal to 80 cc other than generator engines is 300 hours. The proposed durability period for generator engines with displacement less than or equal to 80 cc is 500 hours. The proposed durability 
period for engines with displacement greater than 80 cc and less than 225 cc is 
500 hours. The proposed durability period for engines with displacement greater than 
or equal to 225 cc is 1,000 hours.  The emissions durability periods in the Proposed 
Amendments are the longest of the current durability periods for each displacement  
167 category for engines other than generator engines with displacement less than or 
equal to 80 cc.  
Actual  use times, as found in the CSUF survey (CSUF SSRC, 2019), are often much 
longer than the emissions durability periods defined in the current regulations. For 
example, t he 75th percentile age of in- use residential generators is 15 years . A 
generator used at the average residential activity level of 62 hours per year would be 
used for 930 hours in 15 years. The average professional activity rate is 146 hours per 
year, and the 75th percentile age is 15 years. Those generators would be used for 
2,190 hours in 15 years. The longer emissions durability periods would help ensure 
products meet emission standards over their full lifetimes.  
Generators are not handheld equipment and do not have the same limitations of space and weight as handheld eq uipment. Among generators that use engines with 
displacement less than or equal to 80 cc, most have 80 cc engines. The design of many 80 cc engines is closer to that of an engine with displacement greater than 80 cc 
than it is to that of engines used in handheld equipment.  The example in this section 
illustrates that a residential generator with an engine with displacement less than or 
equal to 80 cc used at the average residential activity level may be used well in excess of its current 50 - to 300 -hour dur ability period. A 500 -hour durability period assures 
more residential generators using engines with displacement less than 225 cc will meet the emission standard for their lifetime.  For all displacement categories except 
greater than 825  cc, there are currently engines certified below the proposed emission 
standards at the longest current emissions durability periods. The proposed emission 
standard s and emissions durability period for engines with displacement greater than 
825 cc are aligned with the current emission standards and emissions durability period 
for similar large spark -ignition engines, i.e., those rated greater than 19 kW and with 
displacement greater than 825 cc.  
In addition to actual use time, many manufacturers advertise use of their products for 
longer than the emissions durability period. Honda’s GX120, GX160, and GX200 engines are among the best -selling general purpose utility engines in California. These 
engines are each certified to an emissions durability period of 500 hours. However, t he 
maintenance schedule in the owner’s manual for these engines indicates the cyclone type air filter should be changed for the first time after 2 years or 600  hours of engine 
operation, and every 2 years or 600 hours thereafter. Changing an air filter is a basic maintenance item and is performed on an engine that will continue to be used, not on 
an engine that is beyond its useful life and can no longer be used. The owner’s manual 
for these engines also recommends the combustion chamber be cleaned after ev ery 
500 hours of operation. This is a more extensive maintenance item than changing an 
air filter, as it involves removing the cylinder head from the engine. It would not be 
practical to perform such maintenance on an engine that had reached the end of its 
useful life. Nonetheless, the owner’s manual suggests an owner could perform this 
maintenance at least twice, since it is to be performed after every 500 hours of 
operation (rather than after 500 hours of operation). Westerbeke’s 9.9E, J3 and J4  
168 generator s are each certified to an emissions durability period of 250 hours, but their 
website says, “It is not uncommon to hear that generator sets and engines have run up 
to 10,000 hours with no major repairs.” (Westerbeke, 2016). Echo’s CS- 310 chainsaw is 
certified to an emissions durability period of 50 hours. The operator’s manual 
recommends several maintenance items, such as replacing the air filter and inspecting, 
cleaning, or replacing the spark plug and muffler spark arrestor every 3 months or 
90 hours of operation (Echo, 2020). The operator’s manual for the CS- 310 also 
recommends an operator inspect or replace the fuel filter and replace the fuel cap 
gasket yearly or after 600 hours of operation. Engine manufacturers measure emissions from their engines through the end of the emissions durability period in 
certification testing to demonstrate that their engines will meet the emission standards 
or FELs for the engines’ entire useful life. Emissions are expected to continue to increase as engines are operated  beyond the emissions durability period. The 
discrepancy between the emissions durability periods and the actual number of 
operating hours for engines means the engines may be emitting at levels above the 
emission standards for a large portion of their use time.  
Therefore, based on this better understanding of engines’ actual life in terms of operating hours, the proposed change to emissions durability periods is necessary to 
more accurately reflect the current lifetime use period of engines and to ensure excess 
emissions do not occur over the life of the engines. These durability periods are technologically and economically feasible.  
As discussed further in section F of this chapter, the Proposed Amendments add 
flexibility for manufacturers by allowing them to select a longer emissions durability 
period than what is specified in § 2403(b)(1). This added flexibility could enable 
manufacturers to generate emission reduction credits for engines that are designed to 
have a useful life longer than the 300- , 500 -, or 1,000- hour emissions durability periods 
listed in § 2403(b)(1 ). The proposed emissions durability periods may not ensure all 
engines meet the emission standards throughout their life because some engines are used beyond the proposed emissions durability periods. However, the Proposed Amendments will require every engine to meet the longest of the current ly applicable 
emissions durability periods, which will increase the  portion of engines that are 
expected to meet the emission standards throughout their  life. The proposed 
emissions durability periods also can be implemented more quickly than emissions durability periods that exceed the length of the current options. Further testing would 
be required to determine whether emissions durability periods that exceed the length 
of the current options are technologically feasible . Implementing the proposed 
emissions durability periods will help achieve the maximum technologically -feasible 
emission reductions at the earliest date.  
Improved table headings : The change in the table headings for PM emission standards 
from “Particulate” to “Particulate Matter” is necessary to clarify the existing requirements and does not change the emission standards or their applicability.   
169 § 2403(b)(2)  
Purpose. The current regulations in § 2403(b)(2)  establish voluntary,  more  stringent  
exhaust  HC + NO x and PM emission standards  and other  requirements for engines to 
be designated  “Blue Sky Series”  engines.  The Blue Sky Series  emission s tandards  were  
developed  to allow manufacturers  to receive recognition  for certifying  to lower  
standards,  but CARB  has no record  of any spark -ignition engine  family being  certified  
to meet  these voluntary emission standards.  There are three types  of Proposed  
Amendments to this section:  
• The first amends the applicable model years to sunset these voluntary emission 
standards for engines produced after MY  2023  due to lack of use by 
manufacturers . Under the current regulations, the voluntary emission standards 
do not have an end date. The Proposed Amendments add  the text, “ valid 
through model year 2023,” to the first sentence of §  2403(b)(2) to specify the 
Blue Sky Standards will apply only through MY  2023  for consistency with 
Proposed Amendments to other sections. The Proposed Amendments also replace “and subseq uent” with “through 2023” for the applicable model years 
in the table of voluntary emission standards that follows § 2403(b)(3) to specify 
the Blue Sky Standards will apply only through MY  2023.  
• The second amendment adds the text, “ , and amended [insert amended date] ” 
to the references to the below two test procedures cited in § 2403(b)(2)(B), to 
include the last amended date for each.  
California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines ; Engine -Testing Pr ocedures (Part 1054)  
California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine -Testing Procedures (Part 1065)  
• The third amendment changes the heading for PM emission standards from “Particulate” to “Par ticulate Matter” in the table of voluntary emission 
standards that follows § 2403(b)(3) .  
The Proposed Amendments include a placeholder for the amended date, “ [insert 
amended date] ”, that will be updated to reflect the CARB adoption date of the 
Proposed Am endments to these procedures described in sections F and  G later in this 
chapter, and provided in their entirety in Appendices F and  G. Per current regulations 
in § 2403(b)(2)(B), m anufacturers of zero -emission small off -road equipment applying 
for Blue Sk y Series designation must file an application of certification  and comply with 
the administrative requirements outlined as applicable in these test procedures. The 
Proposed Amendments to these procedures do not affect the administrative 
requirements for th e manufacturers applying for Blue Sky Series designation.  
Rationale . As described in the prior section of this chapter, beginning with MY  2024, 
the Proposed Amendments set the exhaust HC  + NO x and PM emission standards for 
all SORE except generator engines  to zero, and set more stringent emission standards 
for generator engines. The Proposed Amendments set the exhaust emission standards  
170 for generator engines to zero beginning in MY  2028. The Blue Sky Series standards 
will no longer be lower than the exhaust  emission standards once the emission 
standards of zero become effective. These changes obviate the need to certify any 
SORE generators to the Blue Sky Series standards beginning in MY  2028, and any 
other SORE equipment beginning earlier in MY  2024. Staff expects sunsetting the Blue 
Sky Series standards will not have any impacts on manufacturers or individuals because 
no manufacturer has yet certified any SORE to meet the Blue Sky voluntary emission 
standards.  
The changes to the citations to the two test pr ocedures are necessary to provide 
consistency given the Proposed Amendments include changes to the procedures. 
However, the Proposed Changes to the procedures do not affect the requirements for 
manufacturers applying for Blue Sky Series designation.  
The change from “Particulate” to “Particulate Matter” in the PM emission standards column heading in the table of voluntary emission standards is necessary to provide 
consistency with proposed changes to the exhaust emission standards tables in § 2403(b)(2). The change clarifies the existing requirements and does not change the 
voluntary emission standards or their applicability.  
§ 2403(b)(3)  
Purpose. Section  2403(b)(3) currently states: “ In lieu of meeting the requirements of 
subsection 2403(b)(2)(B), manufacturers of zero -emission small off -road equipment 
may obtain zero -emission equipment credits as detailed in section 2408.1.” In the 
current regulations, this section appears before the “Voluntary Emission Standards” table. However, this table is referenced by §  2403(b)(2)(B), which precedes 
§ 2403(b)(3), and § 2403(b)(3) does not reference the table. To fix this sequence error, 
the Proposed Amendments re- locate §  2403(b)(3) text to follow the “Voluntary 
Emission Standards” table.  
Rationale . This chang e is necessary to correct a table placement error made at the 
time the current regulations were adopted, which will improve readability and prevent confusion. This change does not affect any requirements for SORE certification and testing.  
§ 2403(d)  
Purpos e. Current regulations in §  2403(d) set forth applicable test procedures for 
determining compliance with standards for exhaust emissions from new SORE. The Proposed Amendments add the text, “, and amended [insert amended date] ” to the 
references to the bel ow two test procedures cited in §  2403(d), to incorporate the 
amended date for each.  
California Exhaust  Emission Standards  and Test Procedures  for New 2013 and 
Later Small  Off-Road  Engines;  Engine- Testing  Procedures  (Part  1054)   
171 California Exhaust  Emission Standards  and Test Procedures  for New 2013 and 
Later Small  Off-Road  Engines;  Engine- Testing  Procedures  (Part  1065)  
The Proposed Amendments include a placeholder for the amended date, “ [insert 
amended date] ”, that will be updated to reflect the CARB adopti on date of the 
Proposed Amendments to these procedures.  
Rationale . This change is necessary to ensure manufacturers follow the most 
up-to-date testing procedures for SORE. Adding the amendment dates for the test 
procedures clarifies the versions of the te st procedures that must be used. Most 
proposed updates to the test procedures would further harmonize CARB’s test 
procedures with Title 40, Code of Federal Regulations, Part  1054 and Part  1065 
(“federal Part 1054 and Part 1065”) test procedures and incorpo rate updates made to 
federal Part 1054 and Part 1065 since CARB’s test procedures were adopted. Sections F and G later in this chapter describe the purpose and rationale for the Proposed Amendments for Part 1054 and Part 1065, respectively, and Appendices F and G 
provide the Proposed Amendments in their entirety.  
§ 2404. Emission Control Labels and Consumer Information  – 1995 and Later 
Small Off -Road Engines  
§ 2404(c)  
Purpose. The current regulations in § 2404 specify  requirements  for engine  or 
equipment  manufacturers  to affix a label  (or labels) on each  production  engine  (or 
equipment,  as applicable)  to provide : 
• The engine or equipment owner and service mechanic with information 
necessary for the proper maintenance of these parts in customer use; and  
• The potential consumer s with information regarding relative emissions levels.  
Section  2404(c)  specifies requirements  for engine  label  location,  content,  and 
formatting.  There are three types  of Proposed  Amendments to this section:  
• Capitalization. The Proposed Amendments delete the current requirement in 
§ 2404(c)(3) to use block letters, numerals, and upper case characters, t o aid in 
making the label text  accessible to everyone, including people with visual 
impairments and assistive technology users. Engine label information would 
continue to be required to be written using sans serif letters. For the same 
reason, the Proposed Amendments change the capitalization of required label 
headings and content text specified in § 2404(c)(4)(A), (C), (E), and (H), and 
§ 2404(c)(5)(B), from all upper case to mixed case.  
• Organization name change. The Proposed Amendments changes the text “the Society of Automotive Engineers” to “SAE” in § 2404(c)(4)(D) to reflect how 
SAE International (previously known as the Society of Automotive Engineers) now refers to itself and its publications.   
172 • Reference edition update. The Proposed Amendments replaces the text, 
“: April 30, 2002”, April 2002,” in the reference to SAE J1930 in §  2404(c)( 4)(D) 
with the text, “Revised March 2017, and which is incorporated by reference in 
this article.” The March 2017 edition of the SAE Recommended Practice document —“Electrical/Electronic Systems Diagnostic Terms, Definitions, 
Abbreviations and Acronyms - Equivalent to ISO/TR  15031- 2”—is the most 
recent edition of the document and supersedes the April 2002 edition. CARB staff evaluated the differences between the two editions and determined  that 
the 2017 edition do es not relax any  labelling requirements and t herefore is an 
appropriate replacement for the 2002 edition.  CARB staff does not expect any 
cost impacts or other adverse effects to industry as a result of the proposed reference update to the March 2017 edition.  
Rationale. The rationales  for the Proposed  Amendments to § 2404(c)  are as follows:  
• The capitalization changes are necessary to make label text easier to read and 
consistent with current accessibility guidelines. All capital, block lettering is 
more difficult for many people to read. Using a sans s erif font and mixed -case 
letters is most accessible. Removing the requirement to use block letters and numerals will give manufacturers additional flexibility in creating emission control labels that meet the requirements of § 2404.  
• The organization name change is necessary to provide clarity necessary to help ensure the correct document is referenced by manufacturers, given the organization formerly known as the Society of Automotive Engineers is now known as SAE International.  
• The reference edition update is necessary to better enable widely -understood 
label information by incorporating the most recent version of the SAE procedure by reference in the regulations to ensure manufacturers use the most recently updated terms. In addition, industry requested that CARB reference 
the most recent versions of industry standards documents to prevent  potential 
confusion and the additional cost of maintaining and referencing multiple 
editions , given manufacturers typically use the most recent editions of 
standards doc uments in addition to any earlier editions required by regulations.  
§ 2404(l)  
Purpose. The current regulations in § 2404(l) specify requirements for the Air Index 
label content and locations. For engines certified to emission standards subject to an 
emissi ons durability period as set forth in § 2403(b) and for engines used to meet the 
requirements of §2403(c), each engine manufacturer currently must make Air Index and durability period information available to potential consumers. The Air Index for each eng ine family is determined by a formula provided in § 2404(l)(1). The Air Index 
equals the Family Emission Level (or emission standard, if averaging is not being used) 
for the engine multiplied by three (3) and divided by the HC + NO
x emission standard, 
as applicable in § 2403 (b). Section 2404(l)(2) specifies that the emissions durability  
173 period must be indicated by the actual hours, by the descriptive terms shown in the 
table provided in that section, or by both . The table has two sections, one for 
descriptive terms applicable to MYs  2000 through 2004, and the second for 
descriptive terms applicable to MY  2005 and subsequent model years. The Proposed 
Amendments change model year applicability for the second table section from model year “2005 and subsequent,” to “2005 through 2023,” for consistency with other 
Proposed Amendments.  
The Proposed  Amendments also include the following changes:  
• Correct a typographical error in §  2404(l)(3)(A) by deleting a spurious “the,” 
indicated by strikeout in this sentence: “ The Air Index information should be 
conveyed in the general the  form of the following example. ” 
• Change the capitalization of required label content text specified in 
§ 2404(l)(5)(B) from all upper case to mixed case.  
Rationale. The rationales  for the Proposed  Amendments to § 2404(l)  are as follows:  
• The change to the model year applicability is necessary to provide consistency with the Proposed Amendments to emissions durability periods specified in § 2403(b)(1) for MY  2024 and subsequent model years. The proposed emissions 
durability periods are the same for all engines within a displacement class. 
Therefore, using a descriptive term on the emission control label to supplement 
the number of hours in the emissions durability peri od will no longer be 
necessary.  
• The change to correct a typographical error is necessary to provide clarity for readers and does not change any of the labeling requirements.  
• The capitalization change is necessary to make label text easier to read and consistent with current accessibility guidelines. 
§ 2404(m)(1)  
Purpose. The current regulations in § 2404(m)(1) specify requirements for z ero-
emission equipment label content and placement . The Proposed Amendments correct 
a typographical error by changing a  reference from § 2108.1 to § 2408.1 for accuracy. 
The current regulations reference professional -level speci fications for zero -emission 
SORE indicated in “Table  1, subsection 2108.1(b)(4)(D),” but these specifications are in 
Table  1 in § 2408.1.  
Rationale . This change is necessary to ensure manufacturers are able to reference the 
correct specifications .  
174 § 2405. Defects Warranty Requirements for 1995 and Later Small Off -Road 
Engines  
§§ 2405(c)(1) through (c)(3)  
Purpose . The current regulations in § 2405(c) sp ecify how the warranty on emissions -
related parts will be interpreted. Subsections (1), (2), and (3) all reference 
“Subsection (d)” regarding the requirement to furnish with each new engine written 
instructions for the maintenance and use of the engine by the owner. However, their 
reference text contains a typographical error. Subsection (d) specifies requirements for inclusion of an emission warranty parts list with each new engine, while Subsection (e) specifies the requirement to furnish with each new engine written instructions for the 
maintenance and use of the engine by the owner. The Proposed Amendments correct 
the typographical error by changing the reference from Subsection (d) to (e).  
Rationale . This change is necessary to provide clarity for readers and does not change 
any of the warranty requirements . 
§ 2405(f)  
Purpose. The current regulations in § 2405(f) specify that engine manufacturers must 
submit the documents required by “Subsection (d)” with their certification applications, and that the documents are required as a condition of certification. Section 2405(d) specifies requirements for manufacturers to include an emission 
warranty parts list with each new engine. However, §  2405(e) specifies the requirement 
for manufacturers to include written instructions for the maintenance and use of the 
engine by the owner  with each new engine, and further specifies that the instructions 
must be consistent with this article and applicable regulations contained herein.  To 
provide consistency with the requirements of § 2405(e), the Proposed Amendments 
change the “Subsection (d)” references in § 2405(f) to “Subsections (d) and (e)” so 
that the written instructions that are required to be provided to engine owners are also required to be provided to CARB a s a part of the manufacturer’s application for 
certification.  
Rationale . This change is necessary to improve regulatory certainty by correcting an 
oversight in § 2405(f) that occurred at the time the regulations were adopted. Because 
§ 2405(e) requires that the written instructions be “consistent with this article and 
applicable regulations contained herein,” CARB must receive a copy of the instructions to verify compliance. Also, § 1054.205 (i) requires manufacturers to i nclude  
175 the maintenance and warranty instructions they  will give to the ultimate purchaserhh of 
each new engine. 
§ 2405(h)(1)  
Purpose. The current regulations in § 2405(h) specify z ero-emission equipment 
warranty requirements . The Proposed Amendments add text as indicated in underline 
in the following: “ The manufacturer of zero emission small off road equipment that 
wishes to obtain zero emission equipment credits,  as described in section 2408.1 or 
2408.2,  must warrant to the ultimate purchaser, and each subsequent purchaser, that 
the equipment, including batteries and battery chargers, as applicable, is:  …”  
Rationale . This change is necessary to provide consistency with the Proposed 
Amendments that add a new 2408.2 section  to establish a new, generator -specific 
exhaust emission reduction cred it program.  The proposed addition of “ as described in 
section  2408.1 or 2408.2” to §  2405(h)(1) informs the reader that one of two exhaust 
emission reduction credit programs may be applicable.  
§ 2405.3. Ordered Recalls  
§ 2405.3(a)  
Purpose. The current requirements in § 2405.3(a) specify the steps to be taken by a 
manufacturer and CARB i f the Executive Officer determines that a substantial number 
of any class or category of engin es do not conform to the regulations prescribed 
under §§ 2400 through 2409 w hen in actual use throughout their durability period . 
Subsection 2405.3(a)(1)(B) includes provisions that afford the manufacturer and other 
interested persons an opportunity to present their views and evidence in support 
thereof at a public hearing pursuant to Title 17, California Code of Regulations , 
Division 3, Chapter 1 , Subchapter 1.25 , Article 1.  The Proposed Amendments delete 
this reference and add the following reference: “Chapter 15, Title 13, California Code of Regulations, Section 2771.”  
Rational e. This change is necessary to help ensure manufacturers reference the current 
hearing procedures because Article  1 in Title 17, California Code of Regulations, 
Division 3, Chapter 1 , Subchapter 1.25  has been repealed. The provisions in Title 13 
CCR §  2771  and its internal references to the  Administrative Hearing Procedures for 
Petitions for Review of Executive Officer Decisions (T itle 17, California Code of 
Regulations, Division 3 , Chapter 1 , Article 2, commencing with § 60055.1) provide the 
current hearin g procedures.  
                                            
hh “Ultimate purchaser” means the first  person who in good faith purchases a new 
small off -road engine or equipment using such an engine for purposes other than 
resale.   
176 § 2406. Emission Control System Warranty Statement  
§ 2406(a)  
Purpose. The current requirements in § 2406(a) specify text to be included in emission 
control system warranty statements. The Proposed Amendments change the 
capitalization of requi red headings from all upper case to mixed case t o aid in making 
the label text  accessible to everyone, including people with visual impairments and 
assistive technology users. 
Rationale . This change is necessary to make label text easier to read and consistent 
with current accessibility guidelines . 
§ 2407.  New Engine Compliance and Production Line Testing – New Small 
Off-Road Engine Selection, Evaluation, and Enforcement Action  
§ 2407(a)  
Purpose. The current regulations in § 2407(a)  specify  the compliance  test procedures  
for engines and production  line test procedures.  Currently,  engine families can pass 
compliance  testing  even if many of the engines tested  have  emissions that exceed  the 
emission standard  for one or more  pollutants.  The Proposed  Amendm ents include the 
following changes  to improve  compliance  testing  methods , and to increase the pace  
of compliance  testing,  which  would  reduce the number  of engines sold in California 
that exceed  the emission standards .  
• Current regulations in § 2407(a)(1) specify that the Executive Officer may order 
an engine manufacturer to make available for compliance testing and/or 
inspection ”a reasonable number of engines”, or have an engine manufacturer 
compliance test and/or inspect a “a reasonable number of engines”  at the 
engine manufacturer’s facility under the supervision of a CARB Enforcement 
Officer. The current regulations further specify: “ Engines must be selected at 
random from sources specified by the Executive Officer according to a method approved by the Executive Officer, that, insofar as practical, must exclude 
engines that would result in an unreasonable disruption of the engine 
manufacturer’s distribution system.” The Proposed Amendments change the text “a reasonable number of engines” to “one or more engines” to provide consistency with proposed changes to § 2407(a)(9) [renumbered to 
§ 2407(a)(8)], which would allow as few as one engine to be tested.  
• The current regulations in § 2407(a)(8) specify that engines must be tested in 
groups of five until a “Pass” or “Fail” decision is reached, based on the emission test results, the number of engines tested, and an equation and table of threshold values also specified in § 2407(a)(8). The Proposed Amendments 
remove this entire subsection to provide consistenc y with proposed changes to 
§ 2407(a)(9) [renumbered to § 2407(a)(8)].   
177 • The current regulations in § 2407(a)(9) specify the Executive Officer is required 
to make a failing compliance determination based on the use of the equation 
for the calculation of a quantity “U” and thresholds table currently in § 2407(a)(8), which assess whether the emission test results for the tested 
engines are similar and exceed an applicable emission standard. For example, if 
5 engines subject to an HC + NO
x emission standard of 10 g ·kWh-1 were tested 
and yielded results of 100, 100, 100, 100, and 50 g ·kWh-1, respectively, the 
calculation would give U = 2.17. This would not result in a “Fail” determination. The average emission result for these 5 engines would be 90  g·kWh
-1, 9 times  
the emission standard . Another group of 5 engines would be tested before 
calculating U again. The Proposed Amendments remove this requirement, as 
indicated by strikeout and underline in the following sentence in § 2407(a)(9) 
[renumbered to §  2407(a)(8)], and instead require a failing compliance 
determination if any engine test result exceeds an applicable emission standard:  
“The Executive Officer will find that a group of engines has failed the 
compliance testing  pursuant to the above table  if the Executive Officer 
finds that the average emissions of  the any engines within the selected 
engine family or subgroup exceed the applicable calendar model year 
new engine emission standard for at least one pollutant.”  
• The Proposed Amendments also change “calendar year” to “model year” because, while the historical emission standards were applied by calendar year, the current emission standards are applied by model year.  
• The current regulations in § 2407(a)(10) specify that up to 30 engines may need  
to be tested for the Executive Officer to make a failing compliance determination:  
“If no decision can be reached after 20 engines have been tested, the 
Executive Officer will not make a “Fail” decision for the selected engine family or subgroup on the basis of these 20 tests alone. Under these 
circumstances the Executive Officer will elect to test 10 additional 
engines. If the average emissions from the 30 engines tested exceed any one of the exhaust emission standards for which a “Pass” decision has not been previously made, the Executive Officer will render a “Fail” 
decision. ” 
For example, if 20 engines subject  to an HC + NOx  emission standa rd of 10 
g·kWh
-1 were  tested,  9 of those engines yielded  results of 14 g·kWh-1, one 
engine  yielded a result  of 13 g·kWh-1, and the other  10 engines  yielded  results 
of 9 g·kWh-1, the calculation  would  give U = 2. 27. This would  not result  in a 
“Fail” determination.  The average  emission result  for these  20 engines would  
be 11.5 g·kWh-1, 15 percent higher  than the emissio n standard.  Ten additional  
engines would  be tested,  for a total of 30 engines,  before  making  a “Pass” or 
“Fail” determination.  The Proposed  Amendments remove  this requirement  by 
deleting  the entirety of § 2407(a)(10)  to provide  consistency  with the propose d 
changes  to § 2407(a)(9)  [renumbered  to § 2407(a)(8)].   
178 The Proposed  Amendments also include the following changes to improve  clarity,  to 
provide  consistency  with other  exhaust  emission regulations,  and to correct 
typographical  errors:  
• The current regulati ons in § 2407(a)(1) also specify: “A subgroup may be 
selected for compliance testing only if the Executive Officer has reason to 
believe that the emissions characteristics of that subgroup are substantially in 
excess of the emissions of the engine family as a whole.” The Proposed 
Amendments would remove this requirement to facilitate selection of any engine  for testing. 
• Section 2407(a)(4) currently specifies: “Engine service accumulation (i.e., break -in) before testing may be performed on test engines to the same 
extent it is performed on production line testing engines (See subsection (d)). No break in or modifications, adjustments, or special preparation or maintenance will be allowed on engines chosen for compliance testing without 
the written consent of the Executive Officer. ” To provide consistency with this 
requirement, the Proposed Amendments would make the changes to 
§ 2407(a)(5) indicated by strikeout and underline in this sentence: “If the engine 
manufacturer elects to specify a different break -in or adjustments, they  will may 
be performed by the engine manufacturer  only upon written approval by the 
Executive Officer and  under the supervision of C ARB personnel.”  
• Section  2407(a)(7) currently specifies that engines must be randomly chosen 
from the selected engine family or subgroup , and that e ach chosen engine must 
be tested according to one of the  applicable  emission standards and test 
procedures identified in a list in that section to determine its emissions, depending on the model year . The Proposed Amendments delete the 
parenthetical phrase from the reference to the first procedure in that list, “California Exhaust Emission Standards and Test Procedures for 1995- 2004 
Small Off -Road Engines”  (“Emission Standards and Test Procedures”) , adopted 
March 20, 1992, and last amended July 26, 2004.” The purpose of this change 
is to prevent confusion given that all the procedures referenced in that section have “Emission Standards and Test Procedures” in their titles.  
• The Proposed Amendments also add the tex t, “, and amended [insert amended 
date] ” to the references to the below two test procedures cited in § 2407(a)(7), 
to include the last amended date for each.  
California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road E ngines ; Engine -Testing Procedures (Part 1054)  
California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine -Testing Procedures (Part 1065)  
• The Proposed Amendments include a placeholder for the amended date,  
“[insert amended date] ”, that will be updated to reflect the CARB adoption 
date of the Proposed Amendments to these procedures described in sections F  
179 and G later in this chapter, and provided in their entirety in Appendices F 
and G. 
• Section 2407(a)(7) also specifies: “Procedures must be supplied by the engine 
manufacturer within seven days after the request for such special ity hardware or 
personnel. Failure to supply this unique specialty hardware or personnel may not be used by the engine manufacturer as a cause for invalidation of the 
subsequent tests.” The Proposed Amendments correct a typographical error by replacing “speciality” with “specialty.”  
• The Proposed Amendments change the numbering of §§  2407(a)(9), (11) and 
(a)(12) to (8), (9), and (a)(10), respectively, to accommodate the proposed 
removal of §§  2407(a)(8) and (10) and maintain sequential section numbering.  
Rationale . The changes to §§ 2407(a)(1), (8), (9), and (10) are necessary to adequately 
enforce the exhaust emission standards and achieve emission reductions expected 
under the exhaust emission standards specified in §  2403. CARB developed the 
compliance test procedures through a public process that involved manufacturers and 
other stakeholders and adopted the compliance test procedures in 1990. The engine 
selection and test date evaluation methods allow for variation in engine emission control performance, such that, depending on how many engines are tested, one or more engines from a given engine family or subgroup may have one or more em itted 
pollutants exceed applicable emission standard(s) but overall still be considered in 
compliance so long as the average emissions do not exceed the applicable emission 
standards. The current regulations specify that CARB must test engines in groups of  
five and must test up to 30 engines before coming to a determination of 
noncompliance. As illustrated in one of the examples provided in the purpose of the 
changes to § 2407(a), five engines could be tested and all fail, with average results 
many times the emission standard, but not meet the criterion for a “Fail” decision. In the other example, a “Fail” decision could not be made after testing 20 engines with average results 15 percent above the emission standard. These examples demonstrate 
challenges that can occur when conducting compliance testing. In both cases, noncompliance of the engine family would be evident before a “Fail” decision could be made. It is necessary to pre vent excessive testing before making a “Fail” decision 
for a noncompliant engine family to make enforcement of emission standards more 
efficient. With the flexibility to test one or more engines, CARB will be able to make a 
determination whether additional  testing is needed before the Executive Officer finds 
that an engine family has failed compliance testing.  
Recent evaporative emission compliance testing shows a low rate of compliance 
(CARB,  2016b and 2021f; also see section A  in Chapter II). Based on the amount of 
failed compliance tests, there is likely an even greater number of engines that are out 
of compliance with evaporative emission standards, which increases statewide emissions beyond those contemplated under a regulat ory compliance scenario and 
confounds efforts to achieve emission reductions expected under the 2016 State SIP 
Strategy. The low compliance rate with evaporative emission standards suggests poor  
180 quality management of production engines. It may also suggest  that engines tested 
for certification are not representative of production engines. A manufacturer would 
not have an incentive to submit failing compliance test results, because it could not 
obtain certification with failing results. CARB has no guarantee that certification 
engines are not specifically prepared or adjusted to ensure passing results. If manufacturer noncompliance with exhaust emission standards is similar to 
demonstrated noncompliance with evaporative emission standards, excess exhaust 
emissions are far greater than CARB's current estimates. However, without reducing 
the current burden of testing up to 30 engines before determining that an engine family is noncompliant, CARB will not be able to increase the pace of testing needed 
to enforce emission standards and help reduce emissions. 
In addition, the amount of failed evaporative emission compliance tests suggests 
testing so many engines is not necessary to make a determination on compliance. Furthermore, manufacturers are currently required  to test only one engine for 
certification. This one engine is used to demonstrate compliance with the emission standards. The Proposed Amendments would enable CARB to similarly test one engine for compliance. Finally, the current regulations in § 2407(a)( 11)(A) provide a 
process that incorporates additional data evaluation following a CARB determination 
that an engine family exceeds the emission standards for one or more pollutants: 
“Prior to revoking or suspending the Executive Order, or seeking to enjoin an engine 
manufacturer, the Executive Officer will consider production line test results, if any, and any additional test data or other information provided by the engine 
manufacturers and other interested parties, including the availability of emission 
reductions credits to remedy the failure .” This process would ensure that the 
Executive Officer’s decision regarding suspension or revocation of an Executive Order of Certification would be based on all available emission results and other information 
for the engine family. These findings indicate the current requirements for the number 
of engines to test for compliance are overly onerous. To adequately enforce the 
exhaust emission standards, CARB needs to complete compliance testing in a reasonable timeframe. The proposed changes to § 2407(a) are necessary to increase 
the pace of compliance testing, better ensuring enforcement of emission standards through more compliance testing, which will help reduce emissions. This is vital to control emissions from SORE  in California and protect the health of Californians.  
The rationales  for the additional  Proposed  Amendments to §§ 2407(a)  are as follows:  
• The change to § 2407(a)(1) to remove the requirement that a  subgroup be 
selected for compliance testing only if its emissions characteristics are 
substantially in excess of the emissions of the engine family as a whole is 
necessary to provide consistency with other existing regulations and to better ensure excess emissions do not occur . Engine models are grouped into an 
engine family “based on similar emission characteristics,” as described in the definition of “engine family” in § 2401. Section 1054.230 of the “California 
Exhaust Emission Standards and Test Procedures for New 2013 and Later Small  
181 Off-Road Engines; Engine- Testing Procedures (Part 1054),” describes criteria 
for selecting engine families. Any engine the Executive Officer selects for 
compliance testing should represent the emissions characteristics of the engine 
family.  Therefore, it does not matter whether the Executive Officer selects 
engines from one subgroup of an engine family for compliance testing. Limiting the Executive Officer’s discretion in choosing engines for compliance testing would make enforcing the emission standards more difficult. A llowing t he 
Executive Officer to request a subgroup (e.g., a specific engine model ) to test 
without the need for a discussion regarding a “reason to believe that the emissions characteristics of the subgroup are substantially in excess of the emissions of the engine family as a whole” would better enable CARB to enforce the exhaust emission standards and prevent excess emissions.  
• The proposed changes to § 2407(a)(5) to require written approval by the 
Executive Officer is necessary to provide consistency with the req uirements 
stated in § 2407(a)(4) and to prevent confusion for manufacturers. This 
proposed change would not affect current procedural requirements but instead 
improves clarity and regulatory certainty. The current requirement in 
§ 2407(a)(4) for the break -in period to match that used for certification testing 
and production line testing unless otherwise approved by the Executive Officer 
is necessary to ensure compliance testing results can be compared to the 
manufacturer’s certification and production line testing results. If a 
manufacturer requires an exception to the standard break -in period 
requirements or wishes to follow different procedures than those used in 
certification and production line testing, it must receive written approval by the 
Executive O fficer to ensure such an exception is appropriate. Certification 
testing, production line testing, and compliance testing are all intended to 
ensure engines meet emission standards and to produce comparable results. 
Inappropriate changes to break -in or adj ustments could produce emission 
results that could not be compared to certification test results and would not 
represent real world emissions. Approval from the Executive Officer for any 
changes is necessary to prevent an incorrect determination of complia nce, 
which could lead to excess emissions occurring. Providing additional clarity to 
further help ensure any exceptions or alternative procedures are done only with 
Executive Officer approval better helps maintain a level playing field amongst 
manufacturer s. 
• The removal of the briefer title, “ Emission Standards and Test Procedures,” as a 
substitute for the full title, “California Exhaust Emission Standards and Test 
Procedures for 1995- 2004 Small Off - Road Engines ,” is necessary to prevent 
confusion regarding the applicable emission standards and test procedures for 
each model year. Later model years are subject to different emission standards 
and test procedures, which also have “Emission Standards and Test Procedures ” in their titles. The briefer reference to “Emission Standards and 
Test Procedures” should be used only to refer to the group of procedures, not to any individual procedure.   
182 • Including the amendment dates for the “California Exhaust Emission Standards 
and Test Procedures for New 2013 and Later Small Off -Road Engines; 
Engine- Testing Procedures (Part 1054),” and the “California Exhaust Emission 
Standards and Test Procedures for New 2013 and Later Small Off -Road 
Engines; Engine- Testing Procedures (Part 1065),”  is necessary to ensure the 
amended test  procedures are used for compliance testing once they become 
effective. The most up -to-date test procedures must be followed by all 
manufacturers of MY  2013 and subsequent model year engines to ensure SORE 
meet the emission standards. Adding the amendment dates for the test 
procedures clarifies the versions of the test procedures that must be used. Most proposed updates to the test procedures would further harmonize CARB’s test 
procedures with the federal Part 1054 and Part 1065 test procedures and 
incorpor ate updates made to federal Part 1054 and Part 1065since CARB’s test 
procedures were adopted. Sections F and G later in this chapter describe the 
purpose and rationale for the Proposed Amendments to Part 1054 and Part 1065, respectively, and Appendices F a nd G provide the Proposed 
Amendments in their entirety.  
• The correction of the typographical error in §  2407(a)(7) by replacing 
“speciality” with “specialty”  is necessary to improve readability and clarity, and 
does not affect the compliance testing requirements.  
• Changing “calendar year” to “model year” in §  2407(a)(9) [renumbered to 
§ 2407(a)(8)] is necessary to provide consistency with the application of current 
emission standards under § 2403 and prevent confusion for the reader.  
• The change in subsection numbering from §§  2407(a)(9), (11) and (a)(12) to (8), 
(9), and (a)(10), respectively, is necessary to provide consistent numbering  and 
to prevent confusion for the reader.  
All of these Proposed Amendments will help ensure that engines manufactured for 
sale or lease for use in California comply with the exhaust emission standards and 
achieve emission reductions expected under the 2016 State SIP Strategy.  
§ 2407(b)  
Purpose. The current regulations in § 2407(b)  specify  quality- audit  production  line test 
procedures for 1996 and subsequent  calendar  (model) years. The Proposed  
Amendments include capitalization and grammar corrections  for two subsections:  
• The Proposed Amendments correct the capitalization in subsection 2407(b)(3) 
as indicated by underline and str ikeout in the following subsection title text: 
“(3) Alternate Quality Audit Engine Selection Criteria  For The  for the  1996  
Through 1999 Calendar Years.”  
• Subsection 2407(b)(4) specifies the compliance evaluation method and 
notification requirements. Subsec tion 2407(b)(4)(B) specifies: “At the end of the 
quarter, all of the data accumulated during the quarter are evaluated, and the 
compliance of the engine family with the family emission levels or emission  
183 standards, whichever is applicable, is determined. I f a sample size for a 
particular production quarter is less than ten engines, the data from that quarter 
must be combined with all of the data from each successive quarter of the 
calendar year until data from at least ten engines that have been quality aud it 
tested are included in the quarterly evaluation.” The Proposed Amendments replace “less than ten engines” with “fewer than ten engines”  to correct the 
grammar.  
These changes do not affect any of the product line testing, evaluation, or notification 
requirements.  
Rationale . These changes are necessary to correct capitalization and grammar 
mistakes and prevent confusion for readers. Common capitalization convention is to 
not capitalize prepositions and articles, such as “for” and “the,” respectively. Common 
grammar convention is to use the word “fewer” with nouns for countable objects and concepts (discretely quantifiable nouns). Engines are countable objects, so “fewer” is the correct word choice.  
§ 2407(c)  
Purpose. The current regulations in § 2407(c)  specify cumulative  sum production  line 
test procedures  for MY 2000  and subsequent  model years . The Proposed  
Amendments include five changes in four subsections,  § 2407(c)(2)(B)9., 
§ 2407(c)(3)(A)1., § 2407(c)(3)(A)3 ., and § 2407(c)( 4)(A). 
• Subsection 2407(c)( 2) specifies the engine sample selection method 
requirements. Subsection 2407(c)(2)(B)9. specifies: “ Manufacturers may elect to 
test additional randomly chosen engines. All additional randomly chosen 
engines tested in accordance with the testing procedures specified in the 
Emission Standards and Test Procedures must be included in the Sample Size 
and Cumulative Sum equation calculations as defined in paragraphs (B)1 and 
(c)(3)(A)1 of this section, respectively. ” The Proposed Amendments add the 
word “applica ble” before the “Emission Standards and Test Procedures” text, 
and add “ , as set forth in Subsection 2403(d)” after that text, to remind readers 
they will need to select the appropriate procedures from multiple options, 
which are identified in 2403(d).  
• Subsection 2407(c)(3) specifies the procedure and equation for the calculation of the cumulative sum statistic. Subsection  2407(c)(3)(A)1 . provides the 
Cumulative Sum Equation and defines its variables. The Proposed Amendments 
correct a typographical error i n the definition of the variable 
Φ by removing the 
spurious “is” after the equal sign and correcting the capitalization of “the”, indicated by strikeout and underline in this sentence: “
Φ = is the  The sample 
standard deviation and is recalculated after each test. ” 
• Subsection 2407(c)(3)(A)3 . specifies: “ If, at any time during the model year, a 
manufacturer amends the application for certification for an engine family a s 
specified in Part I, Sections 28 and 29 of the 1995- 2004 Emission Standards and  
184 Test Procedures, or Subpart B, §90.120 and §90.122 of the 2005  and Later 
Emission Standards and Test Procedures, as applicable,  by performing an 
engine family modification (i.e. , a change such as a running change involving a 
physical modification to an engine, a change in specification or setting, the 
addition of a new configuration, or the use of a different deterioration factor), all previous sample size and Cumulative Sum statistic calculations for the model year will remain unchanged .” To provide applicable test procedures for all 
model years, the Proposed Amendments change “2005 and Later” in the second reference to “2005- 2012”, and add the following text, “ Subpart C, 
section 1054.225 of the “California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine -Testing 
Procedures (Part 1054),” adopted October 25, 2012, and amended [insert 
amended date].” The Proposed Amendments include a placeholder for the 
amended date, “[insert amended date] ”, that will be updated t o reflect the 
CARB adoption date of the Proposed Amendments to these procedures described in section F later in this chapter, and provided in their entirety in 
Appendix  F. The Proposed Amendments also correct a typographical error by 
replacing “i.e.” with “e.g.,” given the list provided in the parentheses describes examples of potential engine family modifications.  
• Subsection 2407(c)( 4)(A) specifies: “Initial test results are calculated following 
the applicable test procedure specified in “California Exhaust Emission 
Standards and Test Procedures for 1995- 2004 Small Off -Road Engines” or 
“California Exhaust Emission Standards and Test Procedures for 2005 and Later 
Small Off -Road Engines,” as applicable. ” To provide applicable test procedures 
for all model yea rs, the Proposed Amendments change “2005 and Later” in the 
second reference to “2005- 2012”, and add the following text, “or the 
“California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine- Testing Procedures (Part 1054),” adopted 
October 25, 2012, and amended [insert amended date] .” The Proposed 
Amendments include a placeholder for the amended date, “ [insert amended 
date] ”, that will be updated to reflect the CARB adoption date of the Proposed 
Amendments to these procedures described in section F later in this chapter, 
and provided in their entirety in Appendix F.  
Rationale. The rationales  for the Proposed  Amendments to § 2407(c)  are as follows:  
• The addition in § 2407(c)(2)(B)9. of the text “applicable”  and “, as set forth in 
Subsection 2403(d)” before and after “Emission Standards and Test Procedures”, respectively,  is necessary to provide clarity for manufacturers to 
help ensure the correct procedures are followed and all required engine tests 
are included in the sample size and cumulative sum equation calculations. 
Proper inclusion of all engine tests in calculations will help ensure that 
manufacturers identify any noncompliance of their engines.   
185 • The change in § 2407(c)(3)(A)1 . to correct a typographical  error is necessary to 
provide clarity for readers and does not change the calculation method for the 
cumulative sum statistic.  
• The changes in § 2407(c)(3)(A)3. and § 2407(c)(4)(A) to the references for the 
test procedures are necessary to update the references and to ensure 
manufacturers follow the correct procedures for their model year.  
• The change in § 2407(c)(3)(A) 3. to correct a typographical error is necessary to 
provide clarity for readers and does not change the  effect of providing 
examples of amend ments to an application for certification.  
§ 2407(d)  
Purpose. The current regulations in § 2407(d)  specify  the procedures  applicable  to all 
production  line testing . The Proposed  Amendments  include changes in three  
subsections:  
• Subsection 2407(d)(1) specifi es the applicable emission standards and 
procedures for testing. The Proposed Amendments add “applicable” before each mention of the “Emission Standards and Test Procedures” throughout this subsection, and add “as set forth in Subsection 2403(d), ” after th e first mention 
of “Emission Standards and Test Procedures,” to remind readers they will need 
to select the appropriate procedures from multiple options, which are identified 
in 2403(d). This proposed change does not alter current requirements.  
• Subsection 2407(d)(2) specifies that CARB “personnel and mobile laboratories 
must have access to engine or equipment assembly plants, distribution facilities, and test facilities for the purpose of engine selection, testing, and observation. Scheduling of access must  be arranged with the designated engine 
manufacturer’s representative and must not unreasonably disturb normal operations (See Section 31 of the 1995- 2004 Emission Standards and Test 
Procedures or Section  90.126 of the 2005 and Later  Emission Standards and  
Test Procedures, as applicable).” To provide the most recent access requirements, the Proposed Amendments change “2005 and Later” in the second reference to “2005- 2012”, and add the following text, “or section 
1054.821 of the “California Exhaust Emission Standards and Test Procedures for 
New 2013 and Later Small Off -Road Engines; Engine- Testing Procedures (Part 
1054) ,” adopted October  25, 2012, and amended [insert amended date] .” The 
Proposed Amendments include a placeholder for the amended date, “ [insert 
amended date] ”, that will be updated to reflect the CARB adoption date of the 
Proposed Amendments to these procedures are described in section F later in 
this chapter, and provided in their entirety in Appendix  F.  
• Subsection 2407(d)(3) specifies requirements for engine sample selection, § 2407(d)(3)(A) specifies that selected engines must be representative of the 
engine manufacturer’s California sales and describes sample selection 
requirements, and § 2407(d)(3)(B) specifies the type of California sales da ta 
required by model year. Subsection  2407(d)(3)(B)2. specifies: “For the 2000 and  
186 later model years, engine manufacturers must provide actual California sales, or 
other information acceptable to the Executive Officer, including, but not limited 
to, an estimate based on market analysis and federal production or sales.” The 
Proposed Amendments add a new requirement: “Information supporting the manufacturer’s market analysis and any other information forming the basis of a manufacturer’s determination of sales must be provided to the Executive Officer within 30 days upon request.”  
Rationale. The rationales  for the Proposed  Amendments to § 2407(d ) are as follows:  
• The addition in §  2407(d)(1) of the text “applicable” and “, as set forth in 
Subsection 2403(d)” before and after “Emission Standards and Test 
Procedures ,” respectively,  is necessary to provide clarity for manufacturers to 
help ensure the correct procedures are followed  for the model year of each 
engine. This will help ensure that manufacturers identify any noncompliance of 
their engines. The changes in § 2407(d)(2) to the references for the access 
procedures are necessary to update the references and to ensure manufacturers and CARB staff follow the correct procedures.  
• Manufacturers must report sales of  their engines as part of the production line 
testing requirements. This helps to ensure the sample size of engines tested meets the requirements of § 2407. Accurate sales reports are also important for 
purposes of verifying compliance with warranty, emiss ion-related defect 
reporting, recall, and emission reduction credit requirements. Manufacturers are required by the existing regulations to provide actual California sales or other information acceptable to the Executive Officer, including, but not limited  to, 
an estimate based on market analysis and federal production or sales. The 
additional requirement in § 2407(d)(3)(A) to provide supporting information to 
the Executive Officer within 30 days upon request will ensure CARB will receive 
necessary information in a timely manner to enable staff to verify the basis for a manufacturer’s sales figures. Thirty days is a reasonable amount of time to allow for submission of information. This requirement is not expected to have any 
cost impact for manufacturers because manufacturers would not be required to 
create new information. The requirement is merely to provide existing information to the Executive Officer.  
§ 2408. Emission Reduction Credits – Certification Averaging, Banking, and 
Trading Provisions  
§ 2408(a)  and (b)  
Purpose. The current regulations in § 2408( a) describe the applicability of the 
certification averaging, banking, and trading provisions in § 2408, and § 2408( b) 
specifies the general provisions. The provisions currently apply to HC  + NO x (or NMHC  
+ NO x, as applicable) and PM emissions . The Proposed Amendments add CO to the 
list of pollutants for which the provisions apply.   
187 Rationale . The proposed emission standards in § 2403 include more stringent emission 
standards for CO for generator engines and all engines with displacement greater 
than 825 cc. Allowing averaging, banking, and trading of emission reduction credits 
for CO is necessary to facilitate manufacturers’ compliance with the more stringent emission standards. This change will not result in higher overall emissions of CO. It could result in higher emissions of CO from individual engines, but no existing 
provisions in the regulations require CO emissions to be below the emission 
standards. (The requirement is that emissions must not exceed the emission 
standards.) For example, a manufacturer may measure CO emissions of 200 g ·kWh
-1 in 
a certification test, but production engines would not be out of compliance unless 
their emissions exceeded 536 or 549 g ·kWh-1. Allowing averaging, banking, and 
trading of emission reduction credits for CO may also result in manufacturers banking 
a significant amount of credits for future use. Manufacturers have historically banked HC + NO
x credits, as discussed in section A.3 of Chapter III of this Staff Report,  
because they have not used all of the credits they generate in a given model year for averaging or trading. Manufacturers may choose to do the same with CO credits. Banking credits can be used as a strategy to facilitate manufacturers’ compliance with more stringent emission standards that may be adopted at a future date. As a result, 
manufacturers may bank more credits than they need for their engine families and more credits than the market demands for trading. In such a case, credit may expire before th ey are used for averaging or trading. This would result in lower CO  emissions 
from engines on average. The changes to § 2408(b)(6 ) in the Proposed Amendments 
would also prohibit any manufacturer from setting an FEL above the current emission standards to p revent any engine from having higher CO emissions than it does 
currently.  
Under the Proposed Amendments, if manufacturers choose to utilize the proposed 
ABT program for CO, they would be required to demonstrate compliance under the 
averaging, banking, and trading provisions consistent with current requirements for 
the other pollutants. This requirement is necessary for CARB to be able to verify compliance with program requirements, which is necessary to prevent potential 
inappropriate generation and subsequent use of credits that could lead to excess 
emissions. CARB staff expects any potential reporting costs would be negligible and 
would have no impact on costs to consumers because manufacturers would not be required to create new information. Manufacturers are already required to maintain 
and submit sales reports under current regulations for purposes of verifying 
compliance with production line testing, warranty, emission related defect reporting, recall, and emission reduction credit requirements.  
§ 2408(b)(5)  
Purpose. Both exhaust and evaporative emission regulations currently include 
provisions for averaging, banking, and trading programs, also called emission reduction credit programs. The emission reduction credit programs allow manufacturers to gener ate credits when they produce SORE that emit at levels lower  
188 than the current emission standards. These credits may be used to produce SORE that 
emit at higher levels, banked for future years, or traded with other manufacturers. 
Section  2408 provides the requirements for manufacturers’ participation in the 
voluntary certification averaging, banking, and trading program for SORE produced in 
MY 2000 and subsequent  model years .  
The current regulations in § 2408(b)(5)  specify: “A manufacturer may certify engin e 
families at Family Emission Limits (FELs) above or below the applicable emission standard subject to the limitation in paragraph (6) of this section, provided the summation of the manufacturer’s projected balance of credits from all credit transactions f or each engine class in a given model year is greater than or equal to 
zero, as determined under paragraph (f).” The phrase “for each engine class” in the regulations specifies that all exhaust emission credits must be used within the same engine class in which they are generated. The Proposed Amendments remove this requirement by deleting the phrase, “for each engine class,” in order to provide 
additional flexibility for credit usage. In a given model year, the balance of credits from 
all credit transactio ns must be greater or equal to zero across all engine classes. 
Allowing credit calculations across all engine classes increases flexibility for manufacturers.  This proposed change would not impact overall emission reduction 
benefits (i.e., it would not result in excess emissions) because the proposed change does not alter the current requirement that credit balances be greater than or equal to zero.  
Rationale . This change is necessary to incentivize the manufacture of low -emission 
engines and ZEE. The ability to use exhaust emission credits across all engine classes will provide manufacturers more flexibility in planning engine sales to meet California market demand , without increasing overall emissions from SORE equipment. The total 
emissions from credit usage would remain the same, but manufacturers would be able 
to use the credits generated by one engine class for engines in other classes without 
the requirement to maintain a balance of credits that is greater than or equal to zero in each engine class. This flexibility would facilitate compliance with the averaging, banking, and trading provisions when the emission standards are zero for most SORE 
equipment and more stringent for generator engines for MY 2024. Historically, the 
exhaust emission standards for SORE have allowed for relatively high- emitting engines 
to be introduced into California commerce. Requiring the balance of credits from all 
credit transa ctions for each engine class in a given model year to be  greater than or 
equal to zero  has been important to ensure that emission reductions of one class of 
engine do not result in overall higher emissions of engines in other classes. For example, if Class  I walk -behind lawn mower engines had emissions below the emission 
standards and the credits generated by those engines were used to offset higher 
emissions from Class IV string trimmer engines, consumers might be unable to find 
low-emitting string trimmers. Such potential problems would be mitigated under the 
Proposed Amendments by the wide availability of ZEE, the reduction in the maximum FELs in § 2408(b)(6), and the implementation of more stringent emission standards. 
The more stringent emission standards in the Proposed Amendments would reduce  
189 the possibility of extremely high -emitting engines being introduced into California 
commerce. The proposed emission standards also may result in manufacturers 
deciding to phase out high- emitting models or entire classes of engines if it is less 
profitable to produce such engines than to produce different models or classes of 
engines. For example, a manufacturer could determine that using credits to offset emissions from a high- emitting handheld engine that would be  installed in a low -cost 
piece of equipment (e.g., a string trimmer with a retail price of $70) would be less profitable than using those credits to offset emissions from an engine that would be installed in a riding lawn mower with a retail price of $15,0 00. 
§ 2408(b)(6)  
Purpose. Section  § 2408(b)(6)  specifies that no engine family may have  a family 
emission level (FEL)  that is greater than the HC + NO x emission levels  in the table  
provided  in this subsection.  The table  lists the maximum FELs for HC + NO x for each  
displacement  category of engines  by model  year.  As defined  by § 2401(a)(24), “Family 
emission level”  or “FEL”  means  an emission level that is declared  by the manufacturer 
to serve  for the averaging,  banking, and trading  program and in lieu of an emission 
standard  for certification.  The Proposed  Amendments  would  establish new maximum 
HC + NO x and CO emission levels for all SORE  equipment  beginning  with MY 2024  by 
making these changes:  
• For the emission levels applied to model year ranges that do not have an end 
date (e.g., “2005 and subsequent”), the Proposed Amendments replace the 
“and subsequent” text with “through 2023” to limit the applicability of all current emission levels  to model years through 2023.   
• The Proposed Amendments expand the current  table to apply new, more 
stringent maximum emission levels for HC + NO
x and add maximum CO 
emission levels for MY  2024 and subsequent model years. The Proposed 
Amendments set maximum FELs that are approximately 40  to 90 percent more 
stringent  than current maximum FELs for HC + NO x, depending on the engine 
displacement category. The maximum FELs for HC + NO x and CO are equal to 
the applicable current emission standards for each pollutant and displacement category.  
Rationale . Establishing more stringent FELs is necessary to accelerate exhaust emission 
reductions in order to achieve the necessary SORE emission reductions by 2031 as 
expected under the 2016 State SIP Strategy . The new maximum FELs in the Proposed 
Amendments are equal to the current exhaust emission standards for HC + NO x and 
CO. These new, more stringent maximum FELs for HC + NO x would ensure that no 
MY 2024 or subsequent model year engines are introduced for sale or lease for use in 
California with excessive exhaust emissions, while still allowing manufacturers flexibility to use the credits they have generated to sell engines with emissions above the 
proposed, more stringent emission standards in § 2403(b) in the Proposed 
Amendments. The new maximum CO emission levels would ensure that no MY 2024 
or subsequent model year engine introduced into California commerce has emissions  
190 higher than the current applicable CO emission standard. Engines that are currently 
certified to FELs higher than the current emission standards could not be certified for 
introduction into California commerce for MY 2024 or subsequent model years unless 
their emissions were reduced. This will ensure the highest -emitting engines, which 
have the greatest impact on air quality and expose operators to the greatest amounts  
of pollutants, are phased out as soon as possible.  
§ 2408(f)  
Purpose. The current regulations in § 2408(f ) specify the requirements for c redit 
calculation and manufacturer compliance with emission standards.  
Subsection 2408(f )(1) specifies the equation fo r calculation of credits for HC + NO x 
and PM. The Proposed Amendments add CO to the list of pollutants for which credits 
may be calculated.  
Rationale . This change is necessary to provide clarity for manufacturers  and to provide 
consistency with the additio n of CO to the list of pollutants  for which the provisions of 
§ 2408 apply.  Any manufacturer who elects to pa rticipate in the averaging, banking , 
and trading program must do so in compliance with  the regulations set forth in 
§ 2408, including calculating c redits.  
§ 2408(g)(1)(B)  
Purpose. The current regulations in § 2408( g) specify the requirements for certification 
using credits. The current provision in § 2408( g)(1)(B) specifies : “Declare an FEL for 
each engine family for HC+NO x (NMHC+NO x) and Particulate  Matter, if applicable. ” 
The Proposed Amendments add CO to the list of pollutants for which a manufacturer must declare an FEL . 
Rationale . This change is necessary to provide clarity for manufacturers and to provide 
consistency with the addition of CO to the list of pollutants for which the provisions of § 2408 apply.  Any manufacturer who elects to participate in the averaging, banking , 
and trading program must do so in compliance with  the regulations set forth in 
§ 2408, including declaring an FEL for CO . 
§ 2408(g)(1)(E)  
Purpose. The current regulations in § 2408(g) specify the requirements for certification 
using credits. The current provision in §  2408(g)(1)(E) specifies: “Zero emission 
equipment credits can be used to compensate for negative certification emission credits, up to forty percent above the standard. If an engine family has emissions 
higher than forty percent above the standards, certification emission credits can be 
used to account for the remaining emission deficit.” The Proposed  Amendments 
change “Zero emission” to “Zero -emission” and delete the text that limits the usage 
of zero- emission equipment credits to 40 percent to instead allow 100 percent of 
excess emissions from an engine to be offset by zero -emission equipment credits.   
191 Rationale . The change to “Zero -emission” is necessary to provide consistent 
terminology. The compound adjective “zero -emission” is used extensively in the 
regulations when referring to zero -emission equipment. The change to the limit on use 
of zero- emission equipment credits is necessary to further incentivize the manufacture 
of ZEE during the time before emission standards of zero go into effect. The Proposed 
Amendments would encourage the increased manufacture of zero -emission 
equipment by allowing manufacturers to offset all excess emissions above the emission standards, up to the maximum FEL, with zero -emission equipment credits. In 
particular, this would encourage more manufacturers to produce professional -grade 
ZEE, which would grow the mar ket even further and help accelerate the adoption of 
ZEE by professional users. For example, t he fraction of small off -road equipment that 
is ZEE is 6  percent for professional landscapers compared  to 55  percent for residential 
users  (CARB, 2020). This change is needed to achieve emission reductions to ensure 
that California attains its air quality standards as soon as possible.  Only professional -
level ZEE may generate credits under the provisions of § 2408.1. An increase in the 
number of ZEE  engine families  being certified to the requirements of § 2408 .1 will 
increase credit generation, provide flexibility for manufacturers and help to further develop the market for professional -level ZEE.  
§ 2408(h)(5)  
Purpose. The current regulations in § 2408(h) describe requirements for records 
maintenance. Subsection 2408(h)(5) specifies: “Pursuant to a request made by the 
Executive Officer, the manufacturer must submit to the Executive Officer the information that the manufacturer is required to retain. ” The Proposed Ame ndments 
add the text “within 30 days” before “the information” to specify that the manufacturer must submit the information within 30 days of the Executive Officer’s request.  
Rationale . This change is necessary to correct an oversight in §  2408(h)(5) that  
occurred at the time the regulations were adopted. The regulations should have included a deadline for information submission to ensure CARB will receive necessary information in a timely manner to enable staff to verify credit calculations. This change clarifies timing for a manufacturer to submit information pursuant to a request made 
by the Executive Officer. This change is consistent with a comparable requirement in the current SORE regulations for the evaporative emission reduction credit program, which specifies 30 days as the time within which a manufacturer must submit 
information to the Executive Officer upon request. This requirement is in 
§ 2754.1(g)(4) (updated to 2754.1(h)(5) in the Proposed Amendments). Thirty days is a 
reasonable amount of ti me for a manufacturer to provide records it is required to 
retain.  
§ 2408(i)(1)  
Purpose. The current regulations in § 2408(i) specify requirements for end -of-year and 
final reports. Subsection 2408(i)(1) specifies: “ The report must include a calculation of   
192 credit balances to show that the credit summation for each class of engines is equal to 
or greater than zero (or less than zero in cases of negative credit balances as 
permitted in paragraph (f)(3).” The Proposed Amendments remove the text “ for each 
class  of engines”  so that manufacturers would no longer be required to provide credit 
summations by engine class, consistent with the Proposed Amendments to remove 
similar language from §  2408(b)(5) , and to remove §§ 2408.1(c)(3), (c)(4), and (g)(1)(C), 
to allo w manufacturers additional flexibility for credit usage. This proposed change 
would not impact emission reduction benefits (i.e., it would not result in excess emissions) because the proposed change does not alter the current requirement that credit balances be equal to or greater than  zero.  The Proposed Amendments also add 
“)” at the end of the sentence to close the parenthetical phrase, “(or less than zero in cases of negative credit balances as permitted in paragraph (f)(3) .” 
Rationale . The first change is necessary to incentivize the manufacture of a wider 
range of ZEE  in all equipment categories for professional users. The flexibility to use 
exhaust emission credits across all engine classes will allow manufacturers more flexibility in planning engine s ales to meet California market demand, without 
increasing overall emissions from SORE equipment. The total emissions from credit usage would remain the same, but manufacturers would be able to use the credits 
generated by one engine class for engines in other classes without the requirement to 
maintain a balance of credits that is greater than or equal to zero in each engine class. This flexibility would facilitate compliance with the averaging, banking, and trading provisions when the emission standards are zero for most SORE and more stringent 
for generator engines for MY 2024.  
The second change is necessary to correct a typographical error where a parenthesis 
was accidentally not included.  
§ 2408(i)(2)  
Purpose. The current regulations in § 2408(i)  describ e requirements for participants in 
the credit program for end -of-year and final reports. The current regulations in 
§ 2408(i)(2) specify: “The calculation of eligible sales (as defined in section 2401) for 
end-of-year and final reports must be based on the location of the point of first retail 
sale (for example, retail customer or dealer) also called the final product purchase 
location.”  The definition of “p oint of first retail sale” in §  2401(a) is  “the point that the 
engine is first sold directly to the ultimate purchaser.”  The current text of §  2408(i)(2) 
provides “retail customer or dealer” as examples of “the location of the point of first retail sale,” which is incorrect per the adopted definition in § 2401(a). The Proposed 
Amendments remove this examp le text to provide consistency with the definitions and 
calculation methods in §  2401(a).   
Rationale . This change corrects a mistake made in the regulations at the time of their 
adoption, which is necessary to provide consistency with the existing requirem ent to 
calculate eligible sales based on the location of the point of first retail sale. The terms “sales,” “point of first retail sale,” and “ultimate purchaser” are defined in § 2401,  
193 enabling manufacturers to accurately calculate sales in compliance with the 
requirements of this section. The examples provided in this subsection did not add 
clarity. Removing them will ensure the term “point of first retail sale” will be 
interpreted as defined in § 2401.  
§ 2408(i)(6)  
Purpose. This subsection provides that errors discovered by either CARB or the 
manufacturer in the end -of-year report, including errors in credit calculation, may be 
corrected in the final report. The Proposed Amendments change “may” to “must” to require that any errors in credit calculations that are discovered by either CARB or by the manufacturer must be corrected in the final report.  
Rationale . This change is necessary to correct a mistake made when the credit 
program requirements were adopted. This correction is necessary to ensure correct records maintenance and reporting, which in turn is necessary to ensure no excess emissions result from implementation of the credit program.  
§ 2408.1. Emission Reduction Credits – Zero-Emission Equipment Credits 
Averaging, Banking, and Trading Provisions  
§ 2408.1(b)(4)  
Purpose. The current regulations in § 2408.1 identify zero- emission equipment  credits  
averaging,  banking,  and trading  provisions  specific to small  off-road equipment  
produced  in the 2010 and later model  years.  Subsection 2408.1(b)(4)  specifi es that a 
manufacturer of zero- emission small  off-road equipment  that wishes to generate  zero 
emission equipment  credits  must  certify zero- emission equipment  engine families at 
FELs of zero grams  per kilowatt- hour.  The Proposed  Amendments include changes  to 
§ 2408.1(b)(4)  and two of its subsections:  
• The Proposed Amendments change “ zero emission equipment credits ” to 
“zero-emission equipment credits ” because “zero -emission equipment credits” 
is used throughout the regulations.  
• Subsection 2408.1(b)(4)(D) specifies the minimum professional -level 
requirements for zero -emission small off -road equipment, and 
§ 2408.1(b)(4)(D)1. requires an engine family certified as a zero -emission 
equipment engine family to be able to operate continuously, allowing for any 
battery exchanges, for a minimum of one hour and meet the minimum 
specifications indicated in Table 1 in that section. The title of Table 1 is 
“Minimum Professional Level Requirements for Zero -Emission Equipment 
Eligibility. ” Table  1 includes, as applicable,  durability test power load, minimum 
supplied battery capacity, minimum cutter speed and other performance 
requirements or parameters for each equipment type. The Proposed 
Amendments correct a typographical error by replacing “For” with “for” in the 
table title, and remove the minimum cutter speed of 6,500 revolutions per 
minute for edgers and for split boom systems.   
194 • Subsection 2408.1(b)(4)(H) contains two requirements: “1. Batteries in an 
equipment manufacturer’s original standard battery package must be identified 
with unique part numbers that differ from the part numbers of any applicable replacement batteries” and “2. Replacement batteries cannot be used to generate zero -emission equipment credits.” The Proposed Amendments 
remove the first requirement entirely so that there is no longer a requirement to 
differentiate between batteries sold with the equipment and replacement 
batteries by different part numbers. The Proposed Amendments also remove “2.” from the second requirement because under the Proposed  Amendments, 
there would be only one requirement in this subsection and no longer a need for the numbering.  
Rationale. The rationales  for the Proposed  Amendments to § 2408.1(b)(4)  are as 
follows:  
• The change to “ zero-emission equipment credits ” is necessary  to provide  
consistent  terminology. The compound adjective “zero -emission” is used 
extensively in the regulations when referring to zero -emission equipment  or 
zero- emission equipment credits.  
• The correction in §  2408.1(b)(4)(D)1. of the typographical error in the Table 1 
title is necessary to improve readability. The removal of the minimum cutter speed of 6,500 revolutions per minute for edgers and for split boom systems in Table  1 is necessary for Table 1 requirements to better represent the actual 
require ments for performing tasks with professional -level equipment, and to 
enable equipment that performs at the required level to qualify for zero -
emission equipment credits. Removal of the minimum cutter speed would help further incentivize ZEE production and increase the rate of ZEE adoption. Electric equipment often generates more torque than gasoline- powered 
equipment with comparable power. Although edgers and split boom systems that use SORE may need a cutter speed of 6,500 revolutions per minute to 
prevent  the engine from stalling when cutting through thick grass, such high 
cutter speed is not needed for electric equipment. Therefore, the cutter speed 
requirement is not as important for electric equipment. Manufacturers have informed CARB staff that the speed requirement does not represent the true requirements for performing tasks with professional -level equipment. 
Additionally, CARB staff received feedback from users of zero -emission edgers 
and split boom systems that the equipment performs at the required  level 
although it does not qualify for zero -emission equipment credits.  
• The change to § 2408.1(b)(4)(H) is necessary to remove an impediment to 
implementing a portion of the exhaust emission reduction credit program, which is necessary to further encourag e participation in the ZEE credit program 
and encourage increased manufacturing of ZEE. Most professional -grade ZEE is 
sold a la carte (i.e., the tool, batteries, and chargers are sold separately). Differentiating between batteries that are sold as part of  an equipment 
manufacturer’s original standard battery package  and replacement batteries  
195 represents a challenge for manufacturers. Manufacturers and retailers would be 
required to produce and stock uniquely labeled batteries for original purchase 
and repla cement, even though those batteries would be the same product. 
Manufacturers have expressed that this would be infeasible for them. The 
proposed change would encourage and support additional participation in the ZEE credit program.  
§ 2408.1(c)  
Purpose. The current regulations in § 2408.1(c)  specify  four provisions  for averaging:  
“(1) Fifty percent of negative credits from engine families with FELs above the 
applicable emission standard may be offset by positive zero -emission 
equipment credits, as allowed under the provisions of section 2408.1. The 
remaining negative credits must be offset by positive certification emission 
credits. Averaging of credits in this manner is used to determine compliance 
under subsection 2408(f)(2).  
(2) Subject to the limitations  above, zero- emission equipment credits used in 
averaging for a given model year may be obtained from zero -emission 
equipment credits banked in previous model years, or zero -emission equipment 
credits of previous model years obtained through trading.  
(3) Zero- emission equipment credits generated from zero -emission small off -
road equipment that performs equivalently to professional -level spark -ignition 
engine powered equipment, with a displacement of 80cc or less, may only be used to offset emissions from other gasoline -powered equipment with a 
displacement of 80cc or less.  
(4) Zero -emission equipment credits generated from zero -emission small off -
road equipment that performs equivalently to spark -ignition engine powered 
equipment, with a displacement between 80cc and 225cc, may only be used to 
offset emissions from other gasoline- powered equipment with a displacement 
between 80cc and 225cc.”  
In § 2408.1(c)(1), the Proposed Amendments change the text “Fifty percent” to “One hundred percent” in the first sentence, and delete the entire second sentence, so that 100 percent of negative credits from engine families with FELs above the applicable 
emission standard  may be offset by zero- emission equipment credits. In addition, the 
Proposed Amendments remove subsections (c)(3) and (c)(4) to allow manufacturers to utilize zero -emission equipment credits to offset emissions from SORE of any engine 
displacement.  
Rationale . The changes to § 2408.1(c)(1) are necessary to increase flexibility for 
manufacturers, which is necessary to further incentivize the manufacture of ZEE. The Proposed Amendments remove an existing limit for how much of the negative credits from engine families with FELs above the applicable emission standard may be offset by positive zero -emission equip ment credits. In particular, this will encourage more  
196 manufacturers to produce professional -grade ZEE, further developing the market and 
giving professional users more ZEE options. For example, t he fraction of small off -road 
equipment that is ZEE is 6  percent for professional landscapers compared  to 
55 percent for residential users  (CARB, 2020).  This change is needed to help 
accelerate the adoption of ZEE in place of SORE equipment by  professional users, 
such as professional landscapers, to  achieve emission reductions and ensure that 
California attains its air quality standards as soon as possible.  Only professional -level 
ZEE may generate credits under the provisions of § 2408.1. An increase in the number 
of ZEE engine families being certified to the requirements of § 2408.1 will increase 
credit generation, providing flexibility for manufacturers and helping to further 
develop  the market for professional -level ZEE.  
The r emoval of subsections (c)(3) and (c)(4) is necessary to further incentivize the 
manufacture of more ZEE options in all equipment categories for professional users. 
The flexibility to use exhaust emission credits across displacement categories will allow 
manuf acturers more flexibility in planning engine sales to meet California market 
demand , without increasing overall emissions from SORE equipment. The total 
emissions from credit usage would remain the same, but manufacturers would be able 
to use the credits generated by one engine displacement category for engines in 
other displacement categories. This flexibility would facilitate compliance with the 
averaging, banking, and trading provisions when the emission standards are zero for most SORE and more stringent for generator engines for MY  2024. These changes are 
similar to those in § 2408 (b)(5), and the rationale for the changes is also similar.  
§ 2408.1(g)(1)  
Purpose. The current regulations in § 2408.1(g) specify the requirements for 
certification using zero -emission equipment credits. The current provision in 
§ 2408.1(g)(1)(C) specifies that, i n the application for certification, a manufacturer 
using zero -emission equipment credits must : “Indicate that the zero -emission 
equipment credits used came from the s ame displacement category as those needed 
for the engine family. ” The Proposed Amendments remove subsection (g)(1)(C) to 
provide consistency with the Proposed Amendments to § 2408.1(c) that would allow 
manufacturers to utilize zero -emission equipment credi ts to offset emissions from 
SORE of any engine displacement. The Proposed Amendments also change the subsection letters for subsequent subsections from (D) and (E) to (C) and (D), respectively, to accommodate the removal of subsection (C)  and maintain sequential 
section lettering.  
Rationale . The removal of the requirement specified by §  2408.1(g)(1)(C) is necessary 
to provide consistency with Proposed Amendments to § 2408.1(c), which are 
necessary to further incentivize the manufacture of ZEE before emission standards of zero go into effect. The rationale for the proposed removal of § 2408.1(g)(1)(C) is the 
same as the rationale for the Proposed Amendments to remove §§ 2408.1 (c)(3) and (4) 
described above in the prior section of this chapter.  The change in subsection  
197 lettering from (D) and (E) to (C) and (D), respectively, is necessary to provide  consistent 
lettering and to prevent confusion for the reader.  
§ 2408.1(g)(2)  
Purpose. The current regulations in §2408.1(g)(2) specify: “The manufacturer of zero-
emission small off -road equipment may supply the information required in 
subsections  2408.1(g)(1)(C), 2408.1(g)(1)(D), and 2408.1(g)(1)(E), by use of an electronic 
spreadsheet detailing the manufacturer's annual production plans, and the zero -
emission equipment credits generated by each zero -emission equipment engine 
family.” The Proposed Amendments add the text “2408.1(g)(1)(B),” before 
“2408.1(g)(1)(C)” to specify that the information required by § 2408.1(g)(1)(B) also may 
be supplied by use of an electronic spreadsheet. The Proposed Amendments also 
remove the reference to § 2408.1(g)(1)(E) to provide consistency with the proposed 
removal of § 2408.1(g)(1)(C)  and proposed re -lettering of the subsections following 
§ 2408.1(g)(1)(C) . 
Rationale . The addi tion of the reference to §  2408.1(g)(1)(B) is necessary to correct an 
oversight in §2408.1(g)(2) that occurred at the time the regulations were adopted. A 
reference to §  2408.1(g)(1)(B) should have been included because § 2408.1(g)(1)(B) is 
projected sales volume, which is important in the calculation of total credits and may 
be easier to submit by use of an electronic spreadsheet. Removing the reference to 
§ 2408.1(g)(1)(E) is necessary to update the references to reflect the proposed 
changes to § 2408.1(g )(1) and prevent confusion for the reader. These changes allow 
for the use of a spreadsheet to supply similar information to that listed in § 2408(g)(2), 
which includes information from three subsections of § 2408(g)(1).  
§ 2408.1(h)(5)  
Purpose. The current  regulations in § 2408.1(h)  describe requirements for records 
maintenance. Subsection 2408.1(h)(5) specifies: “ Pursuant to a request made by the 
Executive Officer, the manufacturer must submit to the Executive Officer the information that the manufacturer is required to retain.” The Proposed Amendments 
add the text “within 30 days” before “the information” to specify that the 
manufacturer must submit the information within 30 days of the Executive Officer’s request.  
Rationale . This change is necessary to c orrect an oversight in §  2408.1(h)(5) that 
occurred at the time the regulations were adopted. The regulations should have included a deadline for information submission to ensure CARB will receive necessary information in a timely manner to enable staff to  verify credit calculations. This change 
clarifies timing for a manufacturer to submit information pursuant to a request made 
by the Executive Officer. This change is consistent with a comparable requirement in 
the current SORE regulations for the evaporat ive emission reduction credit program, 
which specifies 30 days as the time within which a manufacturer must submit information to the Executive Officer upon request. This requirement is in  
198 § 2754.1(g)(4) (updated to 2754.1(h)(5) in the Proposed Amendments) . Thirty days is a 
reasonable amount of time for a manufacturer to provide records it is required to 
retain.  
§ 2408.1(i)(1)  
Purpose. The current regulations in § 2408.1(i)  specify requirements for end -of-year 
and final reports. Subsection  2408.1(i)(1) spe cifies: “ The report must include a 
calculation of zero -emission equipment credit balances to show that the zero -emission 
equipment credit summation for each class of engines is equal to or greater than 
zero.” The Proposed Amendments remove the text “for ea ch class of engines”  so that 
manufacturers would no longer be required to provide credit summations by engine class, consistent with the Proposed Amendments to remove the same language from 
§ 2408(b)(5) , and to remove §§ 2408.1(c)(3), (c)(4), and (g)(1)(C), to allow manufacturers 
additional flexibility for credit usage. This proposed change would not impact emission 
reduction benefits (i.e., would not result in excess emissions) because the proposed change does not alter the current requirement that c redit balances be equal to or 
greater than  zero.  
Rationale . This change is necessary to incentivize the manufacture of a wider range of 
ZEE in all equipment categories for professional users. The flexibility to use exhaust 
emission credits across all engine classes will allow manufacturers more flexibility in 
planning engine sales to meet California market demand, without increasing overall emissions from SORE equipment. The total emissions from credit usage would remain the same, but manufacturers would be able to use the credits generated by one engine class for engines in other classes without the requirement to maintain a 
balance of credits that is greater than or equal to zero in each engine class. This 
flexibility would facilitate compliance with the averaging, banking, and trading provisions when the emission standards are zero for most SORE and more stringent for generator engines for MY 2024.  
§ 2408.1(i)(2)  
Purpose. The current regulations in § 2408.1(i)(2) specify: “The calculation of eligible 
sales, as defined in section 2401, for end -of-year and final reports, must be based on 
the location of the point of first retail sale  (for example, retail customer or dealer), 
which is also called the final product purchase location.”  The definition of “p oint of 
first retail sale” in §  2401(a) is “ the point that the engine is first sold directly to the 
ultimate purchaser.”  The current text of §  2408.1(i)(2) provides “retail customer or 
dealer” as examples of “the location of the point of first retail sale,” which is incorrect per the adopted definition in § 2401(a). The Proposed Amendments remove this 
example text to provide consistency with the definition s and calculation methods in 
§ 2401(a).  
Rationale . This change corrects a mistake made in the regulations at the time of their 
adoption, which is necessary to provide consistency with the existing requirement to  
199 calculate eligible sales based on the location of the point of first retail sale. The terms 
“sales,” “point of first retail sale,” and “ultimate purchaser” are defined in § 2401, 
enabling manufacturers to accurately calculate sales in compliance with the requirements of this section. The examples provided in this subsection did not add clarity. Removing them will ensure the term “point of first retail sale” will be interpreted as defined in § 2401.  
§ 2408.1(i)(5)  
Purpose. This subsection provides that errors discovered by either CARB or the 
manufacturer in the end -of-year report, including errors in zero -emission equipment 
credit calculation, may be corrected in the final report. The Proposed Amendments change “may” to “must” to require that any errors in credit calculations that are 
discovered by either CARB or by the manufacturer must be corrected in the final 
report.  
Rationale . This change is necessary to correct a mistake made when the credit 
program requirements were adopted.  This correction is necessary to ensure correct 
records maintenance and  reporting, which in turn is necessary to ensure no excess 
emissions result from implementation of the credit program.  
§ 2408.2.  Emission Reduction Credits – Zero-Emission Generator Credits 
Averaging, Banking, and Trading Provisions  
Purpose. The Proposed Amendments add a new 2408.2  section to establish a new, 
generator -specific exhaust emission reduction credit program.  This voluntary program 
would allow manufacturers to offset emissions from generators with emission levels 
above the proposed exhaust emission standards by using credits earned by  zero-
emission generators. All SORE, including generator engines, may be included in 
engine families participating in the  certification  averaging, banking , and trading 
program described in § 2408. Zero -emission genera tors, however, are not among the 
equipment types included in the zero -emission equipment credits averaging, banking , 
and trading program described in §  2408 .1. The program in § 2408.1  prioritized lawn 
and garden equipment because professional landscapers use such equipment extensively. The emission inventory calculated with SORE2020 indicates that 
generators produce the highest statewide emissions of any small off -road equipment 
type. In 2020, generators account ed for approximately 14 percent of the total 
population of SORE equipment, and 19 percent of all ROG and  NO
x emissions from 
SORE (CARB, 2020).  Generators also operate somewhat differently from other 
equipment types. Because their function is to provide electrical power rather than 
perform mechanical work (as lawn and garden equipment does), zero -emission 
generators often do not contain an electric motor. Instead, zero -emission generators 
often convert chemical energy to electrical energy without the use of an electric 
motor. Th is makes incorporation of zero -emission generators into the same zero -
emission equipment credits averaging, banking, and trading provisions as lawn and 
garden equipment less straightforward.   
200 The Proposed Amendments add a new and separate program for zero -emission 
generators for simplicity. The program is tiered, granting more emission reduction 
credits for zero -emission generators with greater energy storage and power delivery 
than for those with less energy storage and power delivery. The purpose of the ti er 
system is to provide the greatest credit benefits to manufacturers who develop zero -
emission generators in the least developed sector of the market (i.e., zero -emission 
generators with the greatest energy storage and highest power output). The proposed 
zero- emission generator credits would be subject to similar provisions to those in the 
existing emission reduction credit programs, including a five- year limit on banking 
credits.  
Rationale . This change is necessary to incentivize manufacturers to increase 
development and production of zero -emission generators, particularly zero -emission 
generators with the greatest energy storage and highest power output. Currently, the availability of zero -emission generators is limited and their price is often more than 
that of a comparable SORE generator. This credit program aims to decrease the price of zero- emission generators while allowing increased flexibility for manufacturers of 
SORE generators as more models of zero -emission generators enter the market.  
§ 2408.2( a) 
Purpose. The Proposed Amendments define the applicability of the zero -emission 
generator credit program. The Proposed Amendments specify the program requirements are applica ble to all zero- emission generators as defined in §  2401 
produced in MYs  2022 th rough 2026. The Proposed Amendments establish that 
participation is voluntary, but if a manufacturer elects to participate, it must follow all 
provisions set forth in § 2408.2. In addition, t he Proposed Amendments limit the 
provisions of this section 2408. 2 to HC + NO
x (or NMHC  + NO x, as applicable) 
emissions . 
Rationale . This section is necessary to define which manufacturers are eligible to 
participate in the program to prevent confusion. Including a reference to the newly 
proposed  definition of zero -emission generator provided by the Proposed 
Amendments in § 2 401, rather than restating the definition, prevents unnecessary 
redundancy in the regulations. Like the existing credit programs, the proposed 
generator -specific program is voluntary; nonetheless, to prevent confusion, the 
Proposed Amendments explicitly state that while the program is voluntary, there are 
still requirements for participation. The  Proposed Amendments limit the provisions of 
this § 2408.2 to HC + NO x (or NM  HC + NO x, as applicable) emiss ions, which are also 
included in the existing credit programs. CO and PM emissions are not included in the proposed zero- emission generator credit program. Unlike existing credit programs, 
the Proposed Amendments specify that the generator -specific program is limited to 
zero- emission generators in MYs 2022 through 2026. This model year constraint is 
intended to incentivize manufacturers to accelerate their development and production of zero- emission generators. Manufacturers who certify zero -emission genera tors for  
201 MY 2022 will be able to begin generating credits as early as possible and for the 
maximum amount of time. Their early action could accelerate the market by o ffering 
consumers more  zero- emission generator choices as soon as possible. Manufacturers 
may receive additional benefits from the use or trading of credits earned from their early action. There may be significant demand for credits earned in MY 2022 and 2023 to offset emissions from MY 2024 and subsequent model year SORE generators. 
Ending gen eration of zero- emission generator credits at the end of MY 2026 will limit 
the total time that banked zero -emission generator credits may be used to offset 
emissions of SORE generators.  
Under the Proposed Amendments,  the exhaust and evaporative emission s tandards 
for all generators will be zero  for MY 2028 and subsequent model years. However, 
zero- emission generator credits earned in MY 2026 could be used to offset emissions 
from generator engines through MY 2031. Such a timeline could provide both public 
health benefits and economic benefits for manufacturers. Manufacturers could 
generate credits for MY  2022- 2026 zero -emission generators to offset emissions from 
MY 2022- 2031 SORE generators. Generation of additional emission reduction credits 
would lessen the cost impacts for manufacturers (and those purchasing equipment) , 
especially during the early years of a developing generator market. The implementation of a credit market will spread out the cost impact over a longer period 
by allowing manufacturers to  produce SORE generators for a longer time.  Some 
manufacturers may need additional time for design development, particularly those 
developing zero -emission generators with the greatest energy storage and highest 
power output . At the same time, incentivizing manufacturers to produce zero -emission 
generators sooner by allowing them to earn zero -emission generator credits starting in 
MY 2022, before more stringent emission standards are implemented, would enable more rapid reductions in generator emissions and  associated adverse health impacts in 
California. 
§ 2408.2(b)  
Purpose. The Proposed  Amendments establish four general  provisions  for credit use, 
generation,  and calculation:  
• The first requires that zero -emission generator credits may only be used to 
offset  emissions from engine families that only contain generator engines.  
• The second requires that zero -emission generator credit generation be 
calculated based only on zero -emission generators that are sold and used in 
California. 
• The third allows a manufacturer, at its option, to include its entire production of 
an engine family in its calculation of credit usage for a given model year if using 
zero- emission generator credits to compensate for negative certification 
emission credits (i.e., to compensate for emissions above the applicable 
emission standards) for that engine family .  
202 • The fourth  requires a  manufacturer of zero -emission generators that wishes to 
generate zero -emission generator credits to  certify zero -emission generators at 
a FEL of zero grams per k ilowatt- hour, and explicitly states that certification of a 
zero- emission generator engine family may enable the manufacturer to 
generate positive zero -emission generator credits for averaging, banking, or 
trading, or a combination thereof.  Subsections of this provision also establish 
the following requirements for credit generation:  
o Zero- emission generator energy, power and durability requirements for 
different levels (aka “tiers”) of credit eligibility, that grants more emission 
reduction credits for larger zero -emission generators (those with greater 
energ y storage and higher  power output ), as described in the proposed 
Table  1 of §  2408.2(b)(4)(B);  
o Options for credit generation for zero -emission generators that cannot 
achieve the applicable full durabilit y period;  
o Requirements that a small off -road equipment family must meet to be 
eligible for certification as a zero -emission generator family ; 
o Requirements for durability testing to demonstrate compliance with the durability requirements;  
o Requirements for m anufacturers to provide the consumer with all 
equipment and accessories necessary to meet the durability requirements;  
o Requirements for the specific information a manufacturer of zero -
emission generators must include in the certification application about the operational sequence over one deployment of the zero -emission 
generator; and  
o The requirement for manufacturers to demonstrate compliance under 
the averaging, banking, and trading provisions of this §  2408.2 for a 
particular model year within 270 days after the end of the model year.  
Rationale. These provisions  are necessary  to ensure no excess emissions result  from  
implementation  of the credit program.  The second  and third  provisions  are consistent  
with provisions  in the existing credit programs  and, because of their importance,  are 
restated  here rather than simply referenced  to prevent  confusion  for manufacturers.  
The rationales  for the provisions  that differ  from  those in other  credit programs  are as 
follows.  
• The first provision requires zero -emissio n generator credits to be used to offset 
emissions only from generators in order to further incentivize development of 
the zero -emission generator market. As described in section D.2 of Chapter  I, 
there is still a need for innovation and growth in the zero -emission generator 
market, particularly for zero -emission generators with the greatest energy 
storage and highest power output . Requiring too rapid a transition to zero-
emission generators could have unintended negative impacts on power supply  
203 in some regions of California. The Proposed Amendments to add a generator -
specific credit program are intended to increase flexibility for manufacturers 
and reduce cost impacts of the proposed requirements to accelerate the 
deployment of ZEE. Limiting credit use to offset emissions from generators is necessary to help ensure those benefits for manufacturers also work towards addressing the public’s need for reliable and affordable power supply . Using 
credits earned by zero -emission generators to offset emissions from generator 
engines will ensure that the benefits of the credits are used toward the continued availability of SORE generators as the market for zero- emission 
generators continues to mature. Use of zero- emission generator credits for 
other equipment types could limit options for California consumers to use SORE generators in situations where an appropriate zero- emission generator may not 
yet be available or cost- effective as the market matures . 
• The fourth provision establishes a tiered credit eligibility approach that is necessary to incentivize manufacturers to develop additional zero -emission 
generators in the least developed sector of the market: zero -emission 
generators with the greatest energy storage and highest power output. The program would award a greater amount of credits to zero -emission generators 
that store more energy or produce more power. The credit eligibility ranges from 1,500 g of HC + NO
x credits  for a Level 1 zero -emission generator to 
4,700 g of HC + NO x credits for a Level 4 zero -emission generator. The credits 
generated by a zero -emission generator could offset either a portion or all of 
the emissions from a generator engine, depending on the emission level, power, emissions durability period, and displacement of the generator engine.   
• The fourth provision also establishes a suite of certification requirements necessary to ensure manufacturers obtain credits only for equipment that achieves the goal of this new credit prog ram—increase options in the currently 
least developed sector of the ZEE market —without resulting in the 
inappropriate generation and subsequent use of credits that could lead to excess emissions.  
• The requirement for generator  engines to be certified at a F EL of zero grams 
per kilowatt -hour is necessary to provide clarity that this new credit program 
allows credits to be granted only for zero -emission generators and not for low -
emission generator engines.  
• The requirement for a longer durability period (minimum 500 hours) is 
necessary to incentivize manufacturers to develop zero -emission generators 
that address the public’s need for reliable power supply .  
• The energy and power requirements are necessary to ensure only equipment that fulfills the intent of this generator- specific program are certified for credit 
generation. For example, the first requirement for a Level 1 zero -emission 
generator is to supply 2.5 kilowatt -hours of energy over an 8- hour period. This 
would require an average power delivery of 312.5 watts over an 8 -hour period, 
which represents a modest load on a small generator. The second requirement  
204 for a Level 1 zero -emission generator is to supply surge power of 3,000 watts 
for 10 seconds, to power devices that require greater power on startup, such as 
a refrigerator. These requirements would enable a Level 1 zero -emission 
generator to power a small number of devices. The duration would depend on 
a number of factors, including the power consumption of the devices, the energy storage of the zero -emission generator, if any, and the ability to 
generate power using features such as solar panels or hydrogen fuel. The 
energy and power requirements for Level 2, Level 3, and Level 4 zero -emission 
generators would enable them to power a greater number of devices with 
greater power consumption or power devices for a longer  time. These zero -
emission generators could therefore be used in more situations where consumers currently use SORE generators.  
• The minimum requirements for eligibility  for certification as  a zero- emission 
generator family are necessary to ensure only equipment that fulfill the intent of 
this generator -specific program earn credits. The requirement to have a device 
capable of providing 120 -Volt nominal alternating current power as well as at  
least one NEMA 5- 15 receptacle  is necessary to ensure consumers will be able 
to power common electrical devices. The NEMA 5 -15 receptacle is the most 
common electrical receptacle used in California delivering 120- Volt nominal 
alternating current power. Th e requirement to contain a zero -emission power 
generation device, an energy storage device, or any combination of both of 
these devices is necessary to ensure a zero -emission generator will be capable 
of providing power for consumers’ devices. This requirement is technology 
neutral to allow zero -emission generators that 1) store energy and provide 
power, but may not be capable of generating power once the stored energy 
has been depleted; 2)  generate and deliver power, but may not be capable of 
storing sufficient energy to meet the requirements in Table 1 of this § 2408.2; 
or 3) store energy, generate power, and provide power. The requirement for a zero emission generator to  meet the minimum specifications indicated in 
Table  1 of this § 2408.2 is necessary to  provide certainty to manufacturers 
regarding the durability period, energy, and power requirements for each level of zero- emission generator.  
• The option for a small off -road equipment fam ily that is certified as a zero -
emission generator family, but cannot achieve the full durability period, to  
generate 75 percent of the zero -emission generator credits if the zero -emission 
generator can meet a minimum of 75 percent up to 99  percent of the durability 
period  is necessary t o encourage manufacturers to certify zero -emission 
generators at the earliest date . This will help accelerate zero -emission generator 
market development.  
• Requirements for durability testing to demonstrate compliance with the durability requirements are nec essary for CARB to ensure only generator 
engines that can meet the durability requirements are granted credits. Zero -
emission generators must be sufficiently durable to meet the minimum 
requirements in this section for 500 hours to match the expected life of most  
205 generator engines. Although some generator engines are certified to emissions 
durability periods of 1,000 hours, others are certified to emissions durability 
periods of 50 hours. This proposed zero -emission generator credit program sets 
durability periods of 500 hours. This 500- hour durability period is at least as 
long as that for most SORE generators and could enable more zero -emission 
generators to be certified than could be certified to a 1,000- hour durability 
period. It is necessary for durability testing to be performed in a representative 
configuration to ensure that consumers will be able to achieve the performance 
demonstrated in durability testing. Conducting durability testing using a five-mode duty cycle that is also used for generator engines that have no idle mode, as described in the “California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off Road Engines; Engine Testing Procedures 
(Part 1054),” will ensure zero -emission generator durability testing is 
comparable to generator engine durability testing. Using an electrical load bank 
to apply a load to a zero- emission generator is necessary because generators 
provide electric power rather than performing mechanical work, as other 
equipment types do.  
• Requirem ents for manufacturers to provide the consumer with all equipment 
and accessories necessary to meet the durability requirements are necessary to enable in- use generator performance to be comparable to performance at the 
time of certification testing, which  is necessary to address the public’s need for 
reliable power supply . 
• As defined by current regulations in § 2401(a)(13), the operational sequence 
“reflects periods of equipment use, and applicable battery recharging and 
exchanging .” Requirements that spec ify the information about the operational 
sequence to be included in the certification application for this generator -
specific credit program are consistent with provisions in existing credit programs. These requirements are necessary for CARB to assess th e power 
capabilities and durability of a zero -emission generator, which is necessary to 
determine program eligibility and credit amount. A description of an operational sequence will also help CARB staff verify compliance of zero -
emission generators with the requirements of this § 240 8.2. 
• The requirement for manufacturers to demonstrate compliance under the 
averaging, banking, and trading provisions of this §  2408.2 for a particular 
model year within 270 days after the end of the model year is consistent wi th 
requirements for existing credit programs. This requirement is necessary for 
CARB to be able to verify compliance with program requirements, which is necessary to prevent potential inappropriate generation and subsequent use of 
credits that could lead to excess emissions. CARB staff expects any  potential 
reporting costs would be negligible and would have no impact on costs to 
consumers because manufacturers would not be required to create new information. Manufacturers are already required to maintain an d submit sales 
reports under current regulations for purposes of verifying compliance with  
206 production line testing, warranty, emission related defect reporting, recall, and 
emission reduction credit requirements.  
§ 2408.2(c)  
Purpose. The Proposed  Amendment s establish averaging  requirements that: 
• Allow 100 percent of negative credits from engine families with FELs above the applicable emission standard to be offset by positive zero -emission generator 
credits; and  
• Allow zero -emission generator credits used in averaging for a given model year 
to be obtained from zero -emission generator credits banked in previous model 
years, or zero -emission generator credits of previous model years obtained 
through trading.  
Rationale . These averaging requirements are necessary  to support the key goals of the 
zero- emission generator credit program: allow manufacturers flexibility, while reducing 
emissions from generator engines and accelerating market development of zero-
emission generator options in advance of emission standard s of zero for all generators  
for MY 2028 and subsequent model year s. Allowing all excess emissions from 
generator engines to be offset by zero -emission generator credits is necessary to 
provide manufacturers flexibility to produce SORE generators that may emit at levels higher than the more stringent MY 2024- 2027 emission standards as the market for 
zero- emission generators develops further. This flexibility is warranted as it  supports 
the goal of encouraging manufacturers to produce more zero -emission generators. 
These proposed averaging requirements are consistent with existing requirements and the Proposed Amendments to the existing credit programs.  
§ 2408.2(d)  
Purpose. The Proposed  Amendments establish provisions  for banking  that: 
• Beginning with model year 2022, allow manufacturers to bank zero -emission 
generator credits for use in subsequent model years for the purposes of 
averaging and trading ; 
• Allow manufacturers to bank credits only after submission of all final reports and 
verification of the reporti ng by CARB;  
• Require that, during the model year, and before submittal of the end -of-year 
report, credits originally designated in the certification process for banking will be considered reserved, and may be re- designated for trading in the end -of-
year report and final report;  
• Allow zero -emission generator credits to  be banked for up to five years; 
• Require zero- emission generator credits that are unused after five years to 
expire, and no longer allow these expired credits to be used toward offsetting 
negative certification emission credits from other eligible engine families.  
207 Rationale . These provisions are necessary to ensure that any banked credits are 
calculated correctly and use of banked credits in future years does not result in excess 
emissions.  The five- year expiration date for credits prevents credits from being banked 
indefinitely and provides a known timeline for all new generators sold in California to 
be zero -emission generators. These proposed banking requirements are consistent 
with requi rements for existing credit programs.  
§ 2408.2(e)  
Purpose. The Proposed  Amendments establish provisions  for trading  that: 
• Allow a manufacturer to exchange zero -emission generator credits with other 
manufacturers in trading;  
• Allow zero -emission generator credits banked in previous years to be used for 
trading; and  
• Allow traded zero -emission generator credits to be used for averaging or 
banking for up to five years from the time of zero -emission generator credit 
generation.  
Rationale . The first two provisions  are necessary to enable flexibility for manufacturers, 
which supports one of the goals of this credit program: lessen the initial cost impacts 
for manufacturers (and those purchasing equipment) that could result while the zero -
emission generator market develops further. The five year expiration date from the 
time of credit generation  is necessary to prevent credits from being traded and 
banked indefinitely, which is necessary to prevent excess emissions, and to provide a 
known timeline for all new generato rs sold in California to be zero- emission 
generators. These proposed trading requirements are consistent with requirements for 
existing credit programs.  This consistency is necessary to prevent confusion, 
calculation errors, and costs of additional manufacturer time spent on learning and 
maintaining different methods and resolving errors.  
§ 2408.2(f)  
Purpose. The Proposed  Amendments provide  an equation,  steps,  and definitions 
required  to calculate  HC + NO x zero- emission generator  credits  and assess  
manufacturer compliance  with emission standards.  For calculating  the total credits  
earned  for a zero- emission generator engine  family,  the credits  indicated  in Table  1 in 
subsection (b) are multiplied by the sales of that family.  The Proposed  Amendments  
reference  the existing  definition of sales  provided  in § 2401.  Section  2401(a)(37)  [to be 
amended  to (42)] defines sales  as follows:  
““Sales” or “Eligible sales” means the actual or calculated sales of an engine 
family in California for the purposes of averaging, banking or trading. Upon 
Executive Officer approval, an engine manufacturer may calculate its eligible sales through market analysis of actual federal production or sales volume.… 
Actual sales are sales calculated at the end of a model year based on that 
model year’s production, rather than on estimates of production.”   
208 The Proposed Amendments in § 2408.2( f) also specify that a nnual sales projections are 
used to project credit availability for initial certifi cation , and act ual sales volume is used 
in determining actual credits for end -of-year compliance determination.  
Rationale . An equation with detailed steps and definitions is necessary to ensure 
consistency and provide a fair and equitable process for all manufacturers that choose 
to participate in the credit program. In addition, such consistency is necessary to 
ensure use of credits does not result in excess emissions. The proposed equation and 
steps are consistent with requirements for existing credit pro grams.  This consistency is 
necessary to prevent confusion, calculation errors, and costs of additional manufacturer time spent on learning and maintaining different methods and resolving 
errors.  
§ 2408.2(g)  
Purpose. The Proposed  Amendments specify  requirements  for certification  using  zero-
emission generator credits  that: 
• Identify the specific materials that must be submitted in the certification 
application by a manufacturer using zero -emission generator credits, and allows 
information required by §§  2408.2 (g)(1)(C) and 2408.2(g)(1)(D) to be supplied in 
an electronic spreadsheet;  
• Establish a ll Executive Orders of Certification  issued are conditional upon 
manufacturer compliance with the provisions of this § 2408.2 both during and 
after the model year of production , and f ailure to comply with all provisions of 
this section  will be considered to be a failure to satisfy the conditions upon 
which the Executive Order of Certification  was issued ; and  
• Require the manufacturer to bear the burden of establishing t o the satisfaction 
of the Executive Officer that the conditions upon which the Executive Order of Certification was issued were satisfied or waived . 
Rationale . These requirements are necessary to ensure proper documentation of 
zero- emission generator credit use in certification applications, which is necessary for 
CARB to ensure compliance with program requirements and to prevent excess 
emissions from the improper use of credits. The proposed requirements are consistent with requirements for existing credit  programs.  This consistency is necessary to 
prevent confusion, errors, and costs of additional manufacturer time spent on learning 
and maintaining different methods and resolving errors.  
§§ 2408.2(h) and (i)  
Purpose. The Proposed Amendments specify detailed records maintenance 
requirements in § 2408.2(h) and requirements for end -of-year and final reports in 
§ 2408.2(i). The actions required in these subsections for the proposed zero -emission 
generator exhaust emission reduction credit program are identical to actions required 
by existing credit programs.   
209 Rationale . The addition of records maintenance and reporting requirements is 
necessary for CARB to be able to verify credit balances for participants and their 
compliance with emission standards, and to ensure no excess emissions result from 
credit use. Aligning the proposed records maintenance and reporting requirements with the requirements for other credit programs makes them more easily understood by participants in the credit market, and better ensures their effectiveness in 
preventing any excess emissions to result from credit use.  
B. Evaporative Emission Regulations  
This section provides the summary, purpose, and rationale for each Proposed 
Amendment to CCR  Title 13, Division 3, Chapter 15 §§ 2750 through 2774. 
Appendix  B provides the full proposed regulatory language of these sections with 
Proposed Amendments shown in strikeout and underline formatting.  
Global Amendments throughout the Evaporative Emission Regulations  
Acronym Change  
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before “Air Resources Board,” for consistency with recent CARB 
document style practices designed to improve clarity. 
Rationale . This change reflects the California Air Resources Board’s recent change to, 
and preferred use of, the acronym “CARB” versus the prior acronym, “ARB,” and the 
entire agency title, “California Air Resources Board.”  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents accessible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guideline s. 
Division Name Change and Address Change 
Purpose. The Proposed Amendments change “ Emissions Compliance, Automotive 
Regulations and Science Division” to “ Emissions Certification and Compliance 
Division ” throughout the evaporative emission regulations because of the 
reorganization of divisions within CARB.  In addition, the Proposed Amendments 
change “9528 Telstar Avenue, El Monte, California 91731” to “ 4001 Iowa Street, 
Riverside, CA 92507” to reflect the address of CARB’s new Southern California headqu arters.   
210 Rationale . These change s are necessary because CARB  divisions have been 
reorganized and renamed, and construction of the new Southern California 
headquarters has been completed. The Emissions Certification and Compliance 
Division n ow has  responsibi lity for reviewing certification applications, so the division 
name has been updated.  Division staff and the vehicle emissions testing  laboratories 
will be housed at the new headquarters.  
“Actively Purged” to “Actively- Purged” Term Change  
Purpose. The Proposed Amendments change “actively purged carbon canister” to 
“actively- purged carbon canister” in §§ 2754(b)(1) and 2766(b)(1) to improve grammar 
and consistency.  
Rationale . These changes are necessary to correct nonstandard grammar in the 
previously adopted text . California Administrative Law (Title  1, CCR, § 16(a)(4)) 
requires that California regulations be free of grammatical errors. In addition, these changes provide consistency with Proposed Amendments to §§  2752(a)(1) and 
2754(h), TP -902 §§ 2.2 and 2. 4, which use the term “actively -purged carbon canister,” 
and Proposed Amendments to § 2752(a)(22) and TP -902 § 5.2, which use the term 
“passively -purged carbon canister.”  
Description of Timing for Demonstrating Compliance and Submitting 
Documents  
Purpose. Throughout the regulations, the Proposed Amendments change notations of 
“within nnn days of the end of the model year” to “within nnn days after the end of 
the model year” to increase clarity regarding the deadline by which  compliance must 
be demonstrated or documents must be submitted.  
Rationale . Certification holders are required to demonstrate compliance with credit 
provisions and submit production volume reports after the model year has ended. Changing “of” to “after” better describes when reports are due and clarifies that 
these reports should have complete information from the entire model year.  
Update to References to SAE J1737  
Purpose. SAE J1737 is  the SAE Surface Vehicle Recommended Practice document, 
“Test Procedure to Determine the Hydrocarbon Lo sses from Fuel Tubes, Hoses, 
Fittings, and Fuel Line Assemblies by Recirculation.”  The Proposed Amendments 
remove the phrase “( Stabilized May 2013 )” from references to “SAE J1737” because 
SAE J1737 has been updated since May 2013. SAE International published the newest version in August 2019, and this version of the test procedure will be referenced 
throughout the regulations. SAE J1737 is intended for the determination of the 
permeation of emissions through component walls, as well as through "microleaks" at 
interfaces of assembled components such as fuel lines while controlling temperature 
and pressure independently of each other. SAE J1737 was revised to include an 
alternative test method because  the previous methodology was not adequate to  
211 measure the low emission levels of new materials and constructions.  CARB staff 
evaluated these revisions and has determined that these changes do not relax 
certification standards or testing procedures. In addition, any changes do not 
adversely affect industry and do no t have cost impacts.  
Rationale . SAE J1737 is a test procedure used to determine the permeation emissions 
from fuel hoses in SORE. SAE International previously “stabilized” this document  in 
May 2013, indicating that no further changes would likely be made to this test procedure. In August 2019, SAE International updated SAE J1737 to include test methods that reflect the most up to date technology and industry standards. This reference is being changed to allow the use of the most up to date testing methods 
and technology to determine the permeation emissions from fuel hoses used in SORE. 
For example, the revised procedure adds a third practical mean to determine steady 
state which is to allow the use of an isothermal mini - or micro -sealed housing 
evaporative determination to measure weight change after preconditioning. 
Additionally, as discussed in the purpose and rationale for § 275 2 in this section B of 
this chapter, the Proposed Amendments also change the definition of SAE J1737 in the definitions section o f these regulations to reflect this update.  
“Diurnal” Phrase Changes to Incorporate “Hot Soak” Emissions  
Purpose. As described  in Chapter  II of this Staff Report  and detailed in the following 
sections,  the Proposed  Amendments incorporate  “hot soak”  emissions into the 
evaporative  emission standards  for SORE.  “Evaporative  emission standards”  refers  to 
diurnal  emission standards,  permeation  emission standards,  and hot soak plus diurnal  
emission standards,  as diurnal  emissions,  permeation  emissions,  and hot soak 
emissions  are all types  of evaporative  emissions.  To support  the inclusion of the “hot 
soak”  emissions,  the Proposed  Amendments  make  these phrasing  changes  
throughout  the regulations:  
• Change “diurnal emission rate” to “diurnal or hot soak plus diurnal emission 
rate” or “evaporative emission rate” depending on the context of a particular sentence;  
• Change “diurnal emission standard” to “diurnal or hot soak plus diurnal emission standard;”  
• Change “diurnal emission test results” to “diurnal or hot soak  plus diurnal 
emission test results;” and  
• Change “diurnal emissions” to “diurnal or hot soak plus diurnal emissions” or “evaporative emissions” depending on the context of a particular sentence.  
Rationale . As an engine is operated, it builds up heat, which must be dissipated once 
the engine is no longer operating. The residual heat from the engine dissipates in all 
directions, including to the fuel tank and its contents. As the fuel in the fuel tank is 
heated, both the rate at which liquid fuel vaporizes and the rate at which fuel 
permeates through the fuel tank walls increase. The increase in vaporization rate of the  
212 fuel can lead to excess fuel vapors being emitted to the atmosphere through a fuel 
tank vent or though carbon canister breakthrough. The increase in the permeation rate 
can also lead to excess fuel permeating through the fuel tank walls, resulting in excess 
emissions being emitted to the atmosphere.  As described in Chapter II of this Staff 
Report, the evaporative emission test procedure for comp lete engines consists of 
several steps, including running the equipment and putting it into a sealed housing for 
evaporative determination (SHED), where emissions are collected and measured. 
Under the current regulations, the SHED is first held at 95°F for  one hour. This “hot 
soak” period represents placing a hot engine in storage after use on a hot summer day. This is then followed by a period of cooling and the “diurnal cycle,” a 24- hour 
period during which the engine is exposed to a temperature cycle aki n to a typical 
summer day, including typical overnight cooling. Currently, the evaporative emission standards established for complete engines in § 2754 only apply to the 24- hour diurnal 
cycle, and only emissions during that 24- hour period are used to determine 
compliance with the emission standards. However, some engines tested by CARB have met the 24 -hour diurnal emission standard, but had hot soak emissions several 
times higher than the diurnal emission standards. In order to control these emissions that could reduce the expected benefits of the emission standards, it is necessary to 
change § 2754 to incorporate hot soak emissions into the evaporative emission 
standards. The Proposed Amendments update text throughout the regulations to reflect this change . 
§ 2750. Purpose  
§ 2750(b)  
Purpose. The current regulations in § 2750(b) require manufacturers to select one of 
two allowable options for certification of engines and state that the options are 
identified in § 2754(a) and in § 2754(b) . Those options are referred to as “performance 
certification” and “design certification.” Both options require running loss emissions to 
be controlled during engine operation, which result s in greater evaporative emission 
reductions . Under the current reg ulations, both options are available beginning with 
MY 2006. The Proposed Amendments add new text that requires manufacturers to 
certify each evaporative family to meet the hot soak plus diurnal emission standards in 
§ 2754(a) for MY 2024 and subsequent mo del years. Section  2754(a) specifies the 
diurnal emission and design standards for SORE with displacements greater than 80 cc 
in Table  1 and requires that  diurnal emissions from any SORE with displacement 
greater than 80 cc must not exceed those standards.  Section  2754(b ) requires an 
applicant to submit in the certification application : (1) a determination that running 
loss emissions are controlled from being emitted into the atmosphere; and (2)  either 
the Executive Or der of Certification  number approving the fuel lines  pursuant to 
§ 2767.1, or  test data showing that all fuel lines meet the permeation requirement of 
15 grams of ROG per square meter of surface area of the surface in contact with fuel per day  when tested in accordance with one of the procedures specified in § 2754(b ). 
The current regulations in §  2754( c) require a manufacturer to choose (1)  
213 “performance certification,” and provide diurnal emission test data for the engine or 
equipment model in the evaporative family that is expected to exhibit the highest 
diurnal emission rate relative to the applicable diurnal emission standard, in 
accordance with TP -902; or (2) “design certification,” and provide information  in the 
certification application showing that the fuel tank and carbon canister meet the applicable design standards listed in Table 1  of § 2754. Under the Proposed 
Amendments, design certification would not be an allowable option for MY  2024 and 
subsequent model years.  
Rationale . This change is necessary to ensure engines meet the more str ingent 
emission standards and support the effective inclusion of hot soak emissions in the 
emission standards. The Proposed Amendments specify revisions to § 2754(a)  and add 
a new subsection 2754(d ) that, beginning with MY  2024, would require manufacturers 
to demonstrate compliance with evaporative emission standards that incorporate hot 
soak emissions and to submit data showing that hot soak plus diurnal emissions will 
not exceed the new emission standards prior to certification.  
The current design standards cannot be expected to ensure that engines meet the 
proposed hot soak plus diurnal emission standards because the design standards do not account for all sources of emissions during a TP -902 test. The design standards set 
limits for fuel ta nk and fuel line permeation emissions based on the components’ 
internal surface area and require carbon canisters to have vapor storage working capacity that depends on the fuel tank nominal capacity. However, the design standards do not account for emissi ons from carburetors or connections between 
components of the evaporative emission control system. Whether or not an engine meets the diurnal emission standard depends on the emissions from the carburetor and connections, the quality of the components and their assembly, and other factors, in addition to the compliance of the fuel tank, fuel lines, and carbon canister with the 
design standards. Consequently, to better ensure that certification testing captures all 
potential emissions from the test unit, the Proposed Amendments are necessary to 
allow only performance certification for MY 2024 and subsequent model year generators.  
CARB staff solicited information during public workshops and other stakeholder meetings regarding design standards that would enable engines to meet the proposed emission standards in a way that would make design certification effective. CARB staff did not receive such information, but did receive comments indicating that 
manufacturers believed design certification was a valuable option. The perceived value 
of design certification for manufacturers was not supported with sufficient evidence for CARB to determine that design- certified engines meet the proposed hot soak plus 
diurnal emission standards. Consequently, the Proposed Amendments to § 2750 
require manufacturers to use performance certification to certify each evaporative family to meet the hot soak plus diurnal emission standards  for MY 2024 and 
subsequent model years.   
214 § 2752. Definitions  
§ 2752(a)  
Purpose. The Proposed Amendments add four new definitions to §  2752(a). The newly 
proposed  definitions are numbered (1), (3), (22), and (31) so that they are in 
alphabetical order with the previously included definitions. Consequently, the 
Proposed Amendments also renumber the definitions that were previously included in this section so that all definitions in this section are in alphabetical order and 
sequentially numbered.  
Rationale . The changes are necessary to maintain a correctly- numbered, alphabetical 
list of definitions  and to p revent confusion for the reader.  
§ 2752(a)(1) [newly proposed definition]  
Purpose. The Proposed Amendments add a definition for “actively -purged carbon 
canister” to clarify references to carbon canisters. The current regulations and the 
Proposed Amendments discuss two categories of carbon canisters: actively- purged 
and passively -purged carbon canisters. The newly proposed  definition explains how an 
actively- purged carbon canister relies on the operation of the engine to purge the 
carbon canister of trapped vapors. Defining what constitutes an actively -purged 
carbon canister clarifies which regulatory requirements apply to equipment using an actively- purged carbon canister as opposed to regulatory requirements that only apply 
to equipment using passively -purg ed carbon canisters.  
Rationale . Use of an actively -purged carbon canister meeting the requirements of the 
current regulations means approval by the Executive Officer is not required for running loss determination. This new ly proposed definition is necessa ry to clarify which 
manufacturers are required to seek Executive Officer approval for running loss determination and to clarify which procedure in TP -902 is used for purging the carbon 
canister for testing.  
§ 2752(a)(3) [newly proposed definition]  
Purpose. The Proposed Amendments add a definition for ANSI/OPEI B71.10 -2018 and 
incorporate this standards document by reference. ANSI/OPEI B71.10- 2018 provides 
an update to the 2013 version of the American National Standard performance specifications and test procedures for off -road ground -supported outdoor power 
equipment with gasoline fuel systems. The updated version of this document 
recognizes additional equipment types  for which this standard is applicable, fuel tank 
impact resistance testing, as well as many other durability standards that different 
parts of SORE must meet. This definition was added so that equipment manufacturers may certify their equipment using test data that was generated in accordance with this 
new version of the standard. The Proposed Amendments require all fuel lines to  be 
securely connected to prevent fuel leakage throughout the useful life of the 
evaporative emission control system  and require f uel line assembly testing to  be  
215 conducted in accordance with the Fuel line connection tensile test in section 5.5 of 
ANSI/OPEI B71.10 2018 for MY 2024 and subsequent model years .  
Rationale . The current regulations incorporate by reference the 2013 version of this 
standards document. This definition has been  added so that a manufacturer can 
reference this document in a certification application. Since this is the most up to date version of this set of standards, manufacturers may be required by other agencies, 
distributors, or retailers to certify to these standards. In order to prevent requiring 
unnecessary testing, CARB has determined that the most up to date version of these standards may also be referenced. It is also necessary to include a definition for this standards document because § 275 4(g) in the Proposed Amendments requires testing 
according to this standards document for MY 2024 and subsequent model years.  
§ 2752(a)(3) [renumbered to (5)]  
Purpose. The Proposed Amendments update the definition of CARB certification 
procedure CP -902 to reflect proposed changes to the title, from “ Certification 
Procedure for Evaporative Emission Control Systems on Engines w ith Displacement 
Greater Than 80 Cubic Centimeters” to “ Certification Procedure for Evaporative 
Emission Control Systems on Small Off -Road Engines.”  The Proposed Amendments 
include a placeholder for the last amended date, “ [insert amended date] ”, that will be 
updated to reflect the CARB adoption date of the Proposed Amendments to CP -902. 
Rationale . This change to the definition is necessary because the Proposed 
Amendments include changes to the title of CP -902, as described in the “ Applicability 
Change” subsection in  section E of this chapter. The amended title reflects the 
Proposed Amendments to CP -902 that would apply it to all SORE, rather than just  
those with displacement greater than 80 cc.  
§ 2752(a)(8) [renumbered to (10)]  
Purpose. The Proposed Amendments update the definition of “Evaporative Family” by 
adding the new text, “ or zero- emission small off -road equipment grouped together 
based on simil ar performance characteristics ”, to the end of the “Evaporative Family” 
definition’s first sentence, “ “Evaporative Family” means small  off-road engine  or 
equipment  models in the same engine class that are grouped together based on 
similar fuel system characteristics as they relate to evaporative emissions. ” 
Rationale . This change is necessary to help provide consistent use of terms across the 
evaporative emission regulations and facilitate manufacturers’ participation in the emission reduction credit progra ms, which in turn help  accelerate the deployment of 
ZEE. Updating the definition of Evaporative Family to include ZEE would enable continued use of familiar terms in the newly proposed zero- emission generator credit 
program, which would make  it easier for manufacturers to understand the 
requirements than if new terms were created . Use  of familiar terms would make it  
216 easier for manufacturers  to participate effectively in the newly proposed zero -emission 
generator credit program.  
§ 2752(a)(10) [renumbered to  (12)] 
Purpose. The Proposed Amendments change the reference to Table 1 § 2754(a) to 
“Tables 1, 2, or 3” in the definition of “Evaporative Family Emission Differential Limit” 
(EFELD)  because the Proposed Amendments add Tables 2 and 3 to include proposed 
new emission standards.  
Rationale . This change is necessary because, as defined in §  2752(a)(12), the EFELD  is 
calculated by the difference between the evaporative emission standard fo r the model 
of engine or equipment within the evaporative family that is expected to exhibit the 
highest  emission rate relative to the applicable emission standard  and the evaporative  
model  emission l imit (EMEL ) declared for the model . In § 2754(a), the Pr oposed 
Amendments add new evaporative emission standards for MY  2024 and subsequent 
model years. Those emission standards are provided in new Tables 2 and 3 in the section, so this definition has been  updated to reference those tables.  
§ 2752(a)(22) [newly  proposed definition]  
Purpose. The Proposed Amendments add a definition for “passively -purged carbon 
canister” to clarify references to carbon canisters. The current regulations and the Proposed Amendments discuss two categories of carbon canisters: active ly-purged 
and passively -purged carbon canisters. The newly proposed  definition explains how a 
passively -purged carbon canister relies on the natural vacuum created by normal  
diurnal temperature variations to purge the carbon canister of stored compounds. Defining what constitutes a passively -purged carbon canister clarifies which regulatory 
requirements apply to equipment using a passively -purged carbon canister as 
opposed to regulatory requirements that only apply to equipment using actively -
purged carbon canisters.  
Rationale . Use of a passively -purged carbon canister means approval by the Executive 
Officer is required for running loss determination. This newly proposed  definition is 
necessary to clarify which manufacturers are required to seek Executive Of ficer 
approval for running loss determination and to clarify which procedure in TP -902 is 
used for purging the carbon canister for testing . 
§§ 2752(a)(25), (26), (27), and (28) [renumbered to (28), (29), (30), and (32), 
respectively])  
Purpose. The Proposed  Amendments add the text, “ and which is incorporated by 
reference in this Article ,” to each of the definitions for SAE J30, SAE J1527, SAE 
J1737 , and SAE J2996 , to improve clarity and completeness.  
Rationale . This change is necessary to provide clarity by noting earlier in the 
regulations (where terms are defined) that these SAE procedures are incorporated by  
217 reference. These SAE procedures are the test procedures that current regulations 
require manufacturers to use to determine the permeation emissions from fuel hoses 
when applying for a component certification for a fuel hose. The Proposed 
Amendments to the definitions do not alter current requirements for certification and testing of SORE equipment because the current regulations already state that versions of these procedures are incorporated by reference in § 2754(b)(2), and cite these 
procedures in §§ 2752(a)(7), 2753(b)(2)(B), 2754(b)(2), 2755(b), 2758(b)(2)(B)2., and 
2758(b)(3)(B). It is necessary to incorporate the amended version of SAE J1737 beca use it has not previously been incorporated by reference in the SORE regulations. 
The revised procedure adds a third practical mean to determine steady state , which is 
to allow the use of an isothermal mini - or micro -SHED to measure weight change after 
preconditioning  and does not alter requirements for manufacturers.  
§ 2752(a)(31) [newly proposed definition]  
Purpose. The Proposed Amendments add a new definition for the most recent version 
of SAE J1930 and explicitly incorporate it by reference to reflect the reference to this 
standard later in the current regulations.  
Rationale. This change is necessary  to provide  clarity by defining  and explicitly 
incorporati ng this SAE standard  by reference  in the regulations.  SAE J1930 was 
already  implicitly incorporated  by reference  because  the current  regulations  already  
reference  its use in § 2759(c)(4)(C) as a source  for allowable abbreviations  for use on 
evaporative  emission control  system  certification  label s. The proposed  definition for 
SAE J1930 references the most  recent  version of the standard  available,  March  2017,  
to ensure  manufacturers  use the most  recently updated industry standard  terms,  
definitions, abbreviations,  and acronyms  to enable common  terminology for diagnostic  
tools  and publications. The revised  SAE J1930  standard  adds  references to the 
following SAE and ISO publications: 
• SAE J1979 E/E Diagnostic Test Modes; 
• SAE J2012 Diagnostic Trouble Code Definitions; 
• SAE J2012DA Digital Annex of Diagnostic Trouble Code Definitions and Failure 
Type Byte Definitions;  
• ISO 15031- 2:2010 (Ed. 1) Road vehicles -- Communication between vehicle and 
external equipment for emissions- related diagnostics -- Part 2: Gui dance on 
terms, definitions, abbreviations and acronyms; 
• ISO 15031- 5:2015 (Ed. 3) Road vehicles -- Communication between vehicle and 
external equipment for emissions- related diagnostics -- Part 5: Emissions-
related diagnostic services; and  
• ISO 15031- 6:2015 (Ed. 3) Road vehicles -- Communication between vehicle and 
external equipment for emissions- related diagnostics -- Part 6: Diagnostic 
trouble code definitions.  
218 These added references are intended to better enable manufacturers to understand 
appropriate te rminology when using SAE J1930.  
§ 2752(a)(31) [renumbered to (35)]  
Purpose. The Proposed Amendments update the definition of CARB test procedure 
TP-901 to include an updated “last amended date.” The Proposed Amendments 
include a placeholder for the last amended date, “ [insert amended date] ”, that will be 
updated at the completion of the rulemaking process to reflect the CARB adoption 
date of the Proposed Amendments to TP -901. 
Rationale . This change to the definition is necessary because the Proposed 
Amendme nts include changes to TP -901, as described in section C of this chapter.  
§ 2752(a)(32) [renumbered to (36)]  
Purpose. The Proposed Amendments update the definition of CARB test procedure 
TP-902 to reflect proposed changes to the title, from “Test Procedure for Determining 
Diurnal  Emissions from Small Off -Road Engines ” to “ Test Procedure for Determining 
Evaporative  Emissions from Small Off -Road Engines .” The Proposed Amendments 
include a placeholder for the last amended date, “ [insert amended date] ”, that w ill be 
updated to reflect the CARB adoption date of the Proposed Amendments to TP -902. 
Rationale . This change to the definition is necessary because the Proposed 
Amendments include changes to the title of TP -902, as described on in the “ “Diurnal” 
Phrase Changes to Incorporate “Hot Soak” Emissions” subsection of section D of this chapter. The amended title reflects the Proposed Amendments to TP -902 that would 
require the evaluation of both diurnal and hot soak emissions for comparison to the 
emission standar ds, rather than only diurnal emissions.  
§ 2753. Certification Requirements and Procedures  
§ 2753(a)  
Purpose. The current regulations in § 2753(a) specify which versions of certification 
procedures CP-901 or CP -902 manufacturers (“applicants”) must follow to annually 
certify that their SORE evaporative emission control systems comply with the evaporative emission  standards  set out in §§  2754 through 2757. The required 
versions vary by SORE model year.  For MY 2020 and subsequent model years, the 
current regulations require manufacturers  to follow CP -901, as amended 
September  18, 2017, or  CP-902, as amended September 18, 2017, as applicable. The 
Proposed Amendments require all applicants to follow the amended versio n of 
CP-902 described in section E of this chapter  and provided in its entirety in 
Appendix  E (“updated  CP-902”) for MY  2024 and subsequent model years. For MYs 
2022 and 2023, the Proposed Amendments allow applicants the option of using 
CP-901, last amended September 18, 2017, or CP -902, last amended 
September  18, 2017, as applicable, or the updated CP -902. When using the updated  
219 CP-902, applicants must meet the emission standards for MY  2024 and subsequent 
model years, as shown in the proposed Table 2 or  3 of § 2754, as applicable . 
Rationale . As summarized in Chapter II of this Staff Report, and described further in 
later sections of this chapter, the Proposed Amendments establish new and more 
stringent emission standards and test procedures beginning with MY 2024. The 
proposed changes to this section (§ 2753(a)) are necessary to implement the new 
emission standards and test procedures for MY  2024 and subsequent model years, 
while at the same time continuing to allow flexibility for earlier model years.  
§ 2753(b)  
Purpose. The current regulations in § 2753(b) define certification requirements specific 
to engines with displacement greater than 80 cc. The current regulations do not 
specify model years to which the requirements apply, and therefore the requirements 
currently apply to all model years. In addition, the current regulations allow applicants the option to use certain certified components in place of measuring diurnal emissions of a complete engine with evaporative emission control system using TP -902. The 
Proposed Amendments add text that specifies the requirements will apply only through MY  2023. As described later in this chapter, the Proposed Amendments 
provide text in a new subsection 2753(d) that requires all evaporative families in 
MY 2024 and subsequent model years to undergo full evaporative emission testing 
using TP -902, rather than allowing for design certification. Under the Proposed 
Amendments, the option to use certain certified components in place of evaporative emission testing using TP -902 will not be available after MY  2023.  
Rationale . As described in Chapter II and later sections of this chapter, the Proposed 
Amendments set the evaporative emission standards for all SORE except generator engines to zero, and set more stringent emission standards for generator engines, beginning in MY  2024. The proposed changes to this section (§ 2753(a)) are necessary 
to implement the new emission standards and test procedures for MY  2024 and 
subsequent model years, while at the same time continuing to a llow flexibility for 
earlier model years. Under the Proposed Amendments to §  2753(b) and (d), all SORE 
equipment must use evaporative emission testing using TP -902 for certification. For 
equipment other than generators, evaporative emission credits must be used to offset 
evaporative emissions. Certification using evaporative emission credits already requires performance certification. For generators, it is not known what design standards would ensure engines would meet the more stringent emission standards;  
consequently, the proposed change to § 2753(b) is necessary to allow only 
performance certification for MY  2024 generators and subsequent model years.  
§ 2753(c)  
Purpose. The current regulations in § 2753(c) define certification requirements specific 
to en gines with displacement less than or equal to 80 cc.  The current regulations 
require a n application for certification of an evaporative emission control system to the  
220 fuel tank permeation emission standard specified in § 2755 or § 2757 to include fuel 
tank permeation data for the fuel tank in the evaporative family that is expected to 
exhibit the highest permeation rate relative to the applicable permeation emission 
standard. The current regulations also require an application to detail the criteria used 
to determine which fuel tank in the evaporative family is expected to exhibit the highest permeation rate relative to the applicable permeation emission standard.  
The current regulations do not specify model years to which the §  2753(c) 
requirements apply, and therefore the requirements currently apply to all model years. The Proposed Amendments add text that specifies the requirements will apply only through MY 2023, for consistency with Proposed Amendments to other sections. The 
Proposed Amendments provide text in a new subsection 2753(d) that requires all 
evaporative families in MY 2024 and subsequent model years to  obtain c ertification of 
a complete evaporative emission control system, and to use the same test and 
certification procedures, regardless of their displacement category. Under the 
Proposed Amendments, the separate certification procedure for engines less than 80 cc will not be used after MY 2023.  
Rationale . The change to this section (§ 2753(b)) is necessary to implement the 
proposed new emission standards and test procedures for MY 2024 and subsequent 
model years, while at the same time continuing to allow flexibility for earlier model 
years. Under the Proposed Amendments to § 2753(c) and (d), all evaporative families 
must use performance certification, including those evaporative families for engines with displacement less than or equal to 80 cc.  
§ 2753(d) [newly proposed subsection]  
Purpose. The Proposed Amendments add text in a new subsection 2753(d) that 
requires all evaporative families in MY 2024 and subsequent model years to undergo 
evaporative emission testing using TP -902. Testing applies to both diurnal and hot 
soak emissions using the model in the evaporative family that is expected to exhibit 
the highest ho t soak plus diurnal emissions relative to the applicable hot soak plus 
diurnal emission standard. The Proposed Amendments require all evaporative families in MY 2024 and subsequent model years to  conduct testing in accordance with TP -902 
regardless of thei r displacement category.  The purpose of this change is to ensure all 
engines certified meet the proposed, more stringent evaporative emission standards for SORE.  
Rationale . As described in Chapter II and later sections of this chapter, the Proposed 
Amendme nts set the evaporative emission standards for all SORE except generator 
engines to zero, and set more stringent emission standards for generator engines, beginning in MY  2024. The proposed text in the new subsection 2753(d) is necessary 
to implement the p roposed new emission standards and test procedures for MY  2024 
and subsequent model years.  Under the Proposed Amendments, all evaporative 
families must use performance certification. For equipment other than generators, evaporative emission credits must be  used  to offset evaporative emissions.  
221 Certification using evaporative emission credits  requires whole engine certification 
under current regulations.  
The current design standards cannot be expected to ensure that engines meet the 
proposed hot soak plus diurnal emission standards because the design standards do not account for all sources of emissions duri ng a TP -902 test.  The design standards set 
limits for fuel tank and fuel line permeation emissions based on the components’ 
internal surface area and require carbon canisters to have vapor storage working 
capacity that depends on the fuel tank nominal capacity. However, the design standards do not account for emissions from carburetors or connections between components of the evaporative emission control system. Whether or not an engine 
meets the diurnal emission standard depends on the emissions from the carburetor 
and connections, the quality of the components and their assembly, and other factors, in addition to the compliance of the fuel tank, fuel lines, and carbon canister with the 
design standards. Consequently, to better ensure that certification testing captures all 
potential emissions from the test unit, the proposed text in § 2753(d) is necessary to 
allow only performance certification for MY  2024 and subsequent model year 
generators.  
§§ 2753(d), (e), and (f)  
Purpose. The Proposed Amendments change the list lettering of the existing 
subsections (d), (e), and (f), to (e), (f), and (g), respectively, to provide sequential lettering of the subsections.  
Rationale . This change is necessary because the Proposed Amendments add a new 
subsection 2753(d).  
§ 2753(d)(2) [re- lettered to (e)(2)]  
Purpose. The current regulations in § 2753(d)(2) (now § 2753(e)(2) in the Proposed 
Amendments) state the conditions under which modification of a certified evaporative emission control system invalidates the certification of the control system. The current regulations provide a list of the CP -902 versions applicable to different model years 
that a manufacturer must follow to obtain a new certification when any evaporative emission control system’s certification is invalidated due to an unapproved modification . The Proposed Amendments update the list to include CP -902 with an 
updated “last amended” date. The Proposed Amendments include a placeholder for 
the last amended date, “[insert amended date]”, that will be updated at the 
completion of the rulemaking process to reflect the CARB adoption date of the Proposed Amendments to CP -902. 
Rationale . This change is necessary to provide consistency with the Proposed 
Amendments to require compliance with the proposed new test and certification procedures for SORE beginning with model year 2024, as described later in this chapter.   
222 § 2753(f) [re- lettered to (g)]  
Purpose. The current regulations in § 2753(f) (now § 2753(g) in the Proposed 
Regulations) require a manufacturer whose Executive Order of Certification  has been 
suspended or revoked to  submit diurnal emission test results determined using 
TP-902, as described in § 2753(b) , according to a schedule based on the number of 
noncompliance findings. The current regulations specify that the requirements apply 
only to evaporative familie s using engines with displacement greater than 80 cc . The 
Proposed Amendments add “or hot soak plus diurnal” to the emission test results requirement and add an associated reference to § 2753(d) to determine applicability. 
In addition, the Proposed Amendments delete the text that specifies the data submission requirements apply only to evapo rative familie s using engines with 
displacement greater than 80 cc . 
Rationale . These changes are necessary to provide consistency with the Proposed 
Amendments to the regulations in the earlier sections, §§ 2753(b) and (d). A 
manufacturer whose Executive Order of Certification has been suspended or revoked 
could certify evaporative families with displacement greater than 80 cc to meet the 
diurnal emission standards in § 2754  through MY 2023. For MY 2024 and subsequent 
model years, a manufacturer must certify all of its evaporative families to meet the hot 
soak plus diurnal emission standards in § 2754 . This includes evaporative families using 
engines with displacement less than or equal to 80 cc, which are not currently required to meet diurnal or hot soak pl us diurnal emission standards. It is therefore necessary to 
remove the text that refers to evaporative families using engines with displacement greater than 80 cc  so that evaporative families using engines with displacement less 
than or equal to 80 cc will  also be subject to the requirements of this subsection. 
These changes would ensure a manufacturer whose Executive Order of Certification has been suspended would submit evaporative emission test results, determined using TP-902, that correspond to the applicable evaporative emission standards for MY 2024 
and subsequent model years, according to the schedule in this § 2753(g). Section 4.4 of CP -902 allows certification test data of an evaporative family to  be carried over, in 
lieu of new tests, to subsequent model years, provided there have been no changes to the evaporative emission control system or to any evaporative emission control system 
component , subject to approval by the Executive Officer. Approval to carry 
certification test data over to subsequent model years may not be granted to a 
manufacturer whose Executive Order of Certification has been suspended or revoked. For example, an Executive Order of Certification may be suspended or revoked after 
failing a compliance test. Submission of new certifi cation test data for all of a 
manufacturer’s evaporative families each model year according to the schedule in this 
§ 2753(g)  would better ensure that the families meet the hot soak plus diurnal 
emission standards and that no changes have been made that wo uld cause engines 
not to meet the emission standards.   
223 § 2754. Diurnal and Hot Soak Plus Diurnal Emission and Design Standards  
Purpose. The Proposed Amendments change the title of this section from “ Diurnal 
Emission and Design Standards” to “ Diurnal and Hot  Soak Plus Diurnal Emission and 
Design Standards” to incorporate the change in evaporative emission standards to 
include the hot soak period.  
Rationale . This change is necessary for consistency with the Proposed Amendments to 
later subsections that, beginning in MY  2024, include the hot soak period in addition 
to the diurnal period in the evaporative emission standards.  
§ 2754(a)  
Purpose. The current regulations in § 2754(a) specify the diurnal emission and design 
standards for diurnal emissions from SORE w ith displa cements greater than 80 cc on 
and after the model years specified in Table 1. The Proposed Amendments divide the current §  2754(a) text into two new subsections, (a)(1) and (a)(2), for clarity,  and add 
new text to those new subsections to limit t he applicability of the diurnal emission 
standards in Table 1 in § 2754 to model years through MY 2023.  
New subsection (a)(1) also provides clarity for certain LSI engines subject to the diurnal 
emissions regulations. The Proposed Amendments add the senten ce “The standards 
in Table 1 shall continue to apply to large spark -ignit ion engines subject to section 
2433(b)(4)(B) in Title 13, Chapter 9, Article  4.5 of the California Code of Regulations 
after the 2023 model year.” to new subsection (a)(1). Section 2433 (b)(4)(B) in Title 13, 
Chapter 9, Article 4.5 of the California Code of Regulations  (section 2433(b)(4)(B)) 
require s that LSI engines with an engine displacement less than or equal to 1.0 liter 
that run on a volatile liquid fuel ( such as gasoline) , mus t meet the evaporative emission 
requirements for small off -road engines, which are specified in Title 13, Chapter 15, 
Article 1 of the California Code of Regulations. Prior to this rulemaking, CARB adopted the most recent  substantive  updates to the referenced small off -road engine 
evaporative emission requirements in Title 13, Chapter 15, Article 1 of the California 
Code of Regulations in 2017, which became operative January 1, 2018. M anufacturers 
of these LSI engines have thus been complying with the a forementioned and current 
2017/2018 evaporative emission requirements for small off -road engines, as specified 
in Title 13, Chapter 15, Article 1 of the California Code of Regulations. The Proposed Amendments to section 2754(a)(1) are necessary to  remove confu sion as to which 
emission standards the engines subject to section 2433(b)(4)(B)  must meet.   
The Proposed Amendment in subsection (a)(1) related to these LSI engines do es not 
alter the requirements, rights, responsibilities, conditions, or prescriptions contained in 
the existing regulations as adopted by CARB and approved by OAL because, following approval of this change, applicable LSI engine manufacturers will continue to comply with the existing evaporative emission standards  in Title 13, Chapter 15, 
Article 1 of the California Code of Regulations. Therefore, the adoption of the 
Proposed Amendments to subsection (a)(1) related to these LSI engines is not  
224 expected to cause any cost impacts to the LSI engine manufacturers subject to section 
2433(b)(4)(B).  
In addition, the Proposed Amendments add new subsections (a)(3) through (a)(6), and new Tables 2 and  3 in § 2754, to require new,  more stringent hot soak plus diurnal 
emission standards for MY  2024 and subsequent model years for all engine 
displacement cate gories. The new (a)(3) and (a)(4) subsections and Table 2 in § 2754 
establish new hot soak plus diurnal emission standards for all SORE except generator 
engines beginning with MY  2024. These emission standards are 0.00 grams of organic 
material hydrocarbon  equivalent per test for all engine displacement categories.  
The new (a)(5) and (a)(6) subsections and Table 3 in § 2754 establish new diurnal 
emission standards for generator engines. Under the Proposed Amendments, emission standards for MY 2024 through 2027 generator engines will be 0.50 g/test 
for engine displacement less than or equal to 80 cc, 0.60 g/test for engine displacement greater than 80cc  and less than 225 cc, and 0.70 for engine 
displacement greater than or equal to 225 cc. The Proposed Amendments set  diurnal 
emission standards of zero for MY 2028 and subsequent model year  generator 
engines in all engine displacement categories. The purpose of setting these emission standards to zero is to accelerate the production of ZEE in place of SORE equi pment 
and to meet the 2016 State SIP Strategy emission reductions for the SORE sector . 
Chapter  VIII describes other alternatives considered and provides CARB staff’s 
analyses that support the conclusion that the Proposed Amendments would enable the maximum degree of technologically feasible, cost -effective emission reductions 
from SORE.  
Under the Proposed Amendments, beginning with MY 2024 the evaporative emission standards will cover a greater portion of an engine’s evaporative emissions. This will ensure greater control of evaporative emissions from MY 2024 and subsequent model 
year SORE equipment sold or leased for use in California. Currently, the diurnal emission standards only apply to the 24- hour diurnal cycle, while under the Proposed 
Amendments they  would also apply to the hot soak period. As manufacturers are 
already required to measure and report hot soak emissions, this will not add any 
testing burden or cost. The purpose of this change is to eliminate the potential for 
higher -than-expected hot so ak evaporative emissions, which would reduce the actual 
emission reduction benefits of the diurnal emission standards if the certification testing did not account for those hot soak emissions.  
Rationale . The Proposed Amendments to § 2754(a) are necessary to achieve the 
maximum degree of technologically feasible, cost -effective emission reductions from 
SORE by the earliest practicable date as required by state law. The Proposed Amendments to the evaporative emission standards in § 2754(a), along with the 
Proposed Amendments to the exhaust emission standards described in section A of 
this chapter, are also necessary to achieve emission reductions from SORE expected under the 2016  State SIP Strategy. In addition, these changes are a necessary  
225 component of the strategy to a chieve 100 percent zero -emission from off -road 
vehicles and equipment  operations in the State by 2035, as ordered in EO N -79-20. 
The Proposed Amendments to § 2754(a) are also necessary to clarify that the 
evaporative emission standards in Title 13, Chapter 15, Article 1 of the California Code 
of Regulations applicable to LSI engines subject to section 2433(b)(4)(B) are the 
existing evaporative emission standards.  
As described in section C.2 of Chapter  I, current SORE regulations will not achieve 
emission reductions expected under the 2016 State SIP Strategy. The 2016 State SIP 
Strategy calls for more stringent emission standards and additional incentives to accelerate the transition to ZEE  to prevent SORE emissions from increasing and 
ultimately to achieve emission reductions necessary to attain ambient air quality 
standards for ozone by 2031 and protect the health and welfare of all California resident s. As described in section B of Chapter  III, SORE emission modelling results 
indicate implementa tion of the proposed evaporative and exhaust emission standards 
would result in emission reductions that would meet the expected emission reductions in the 2016 State SIP Strategy measure to reduce statewide SORE emissions of ROG by 36 tpd  reduction and NO
x by 4 tpd  in 2031, as well as emission reduction 
commitments specific to the South Coast and San Joaquin Valley air basins.  
The proposed  new emission standards for all SORE would apply beginning with 
MY 2024 to provide the lead time required  by the federa l Clean Air Act section 209 . 
The federal Clean Air Act  states, “California and such State adopt such standards at 
least 2 years before commencement of the period for which the standards take 
effect.” The two -year period  provides manufacturers with lead  time to develop and 
manufacture  equipment to meet new emission standards  in the Proposed 
Amendments. Implementing  emission standards at the earliest date would result in 
greater emission reductions and further progress in meeting EO  N-79-20. 
Available evidence identified throughout this Staff Report indicates all of the proposed new evaporative emission standards for SORE are technologically feasible and cost -
effective, which is further explained in the rationale provided for the proposed exhaust emission standards in § 2403(b)(1)  in section A of this chapter.  
The Proposed Amendments allow more time for generator engines to meet emission standards of zero by setting the evaporative emission standards for generator engines to zero for MY 2028 rather than MY  2024 as done for other SORE equipment. While 
there are ZEE generators currently available to meet users’ demand and most of their 
basic uses, there is still a need to allow manufacturers more time to continue to 
innovate and grow to meet the future demands of the zero -emission generator 
market. The rationale for this finding is provided with the rationale for the proposed MY 2024- 2027 exhaust emission standards for generator engines in § 2403(b)(1)  in 
section  A of this chapter.   
226 § 2754(b)  
Purpose. The current regulations in § 2754 (b) require an applicant certifying engines or 
equipment to comply with the diurnal emission standards in § 2754  to submit a 
determination in the certification application that running loss emissions are controlled 
from being emitted into the atmosphere  and to provide information showing  that all 
fuel lines meet the permeation emission standard  in Table 1 of § 2754( a). The current 
regulations do not specify model years to which the requirements apply, and therefore 
the requirements currently apply to all model years. The Proposed Amendments add 
text that specifies the requirements will apply only through MY 2023. As described in the purpose and rationale for a new  subsection 2754(d) in section B of  this chapter, 
the Proposed Amendments require an applicant certifying engines or equipment to 
comply with the hot soak plus diurnal emission standards to  provide diurnal and hot 
soak emission test data for testing using TP -902. As described in the purpose and 
rationale for a new  subsection 2754(h) in section B of  this chapter,  the Proposed 
Amendments add a procedure to TP -902 to demonstrate that running loss emissions 
are controlled from being emitted into the atmosphere  and retain the requirement to 
obtain Executive Officer approval for such a determination.  
Rationale . As described in Chapter II and the purpose and rationale for the Proposed 
Amendments to § 2754(a) in section B  of this chapter, the Proposed Amendments set 
the evaporative emission standards for all SORE except generator engines to zero, and set more stringent emission standards for generator engines, beginning in MY 2024. The proposed changes to this section (§ 2754(b )) are necessary to 
implement the new emission standards and test procedures for MY 2024 and 
subseq uent model years, while at the same time continuing to allow flexibility for 
earlier model years. Under the Proposed Amendments to § 2754 (d), all SORE 
equipment must use evaporative emission testing using TP -902 for certification. It is 
not necessary to ensure all fuel lines meet the permeation emission standard in Table  1 of § 2754( a) after MY 2023 because design standards would not apply to 
MY 2024 and subsequent model year engines.  
§ 2754(c)  
Purpose. The current regulations in § 2754(c) require applicant s certifying SORE to 
comply with the diurnal emission standards to also choose one of two options: provide diurnal emission test data in accordance with TP -902; or provide information showing 
that the fuel tank and carbon canister  meet  the applicable design standards listed in 
Table 1 of  § 2754. The current regulations do not specify model years to which the 
requirements apply, and therefore the requirements currently apply to all model years. The Proposed Amendments add text that specifies the requirements will apply only 
through MY  2023. As described in the next section of this chapter, the Proposed 
Amendments provide text in a new subsection 2754(d)  that requires manufacturers to 
submit diurnal and hot soak emission test data to demonstrate compliance with t he 
proposed  hot soak plus diurnal emission standard s in accordance with TP -902 for all 
evaporative families in MY  2024 and subsequent model years. Under the Proposed  
227 Amendments, the option to provide test data or Executive Order of Certification 
numbers for the fuel tank and carbon canister  in place of evaporative emission testing 
using TP -902 will not be available after MY  2023.  
Rationale . The proposed changes to this section are necessary to implement the 
proposed, more stringent evaporative emission standards for MY  2024 and 
subsequent model years, while at the same time continuing to allow flexibility for 
earlier model years. The rationale for this change is the same as that for the change 
proposed for §  2753(b), provided in the purpose and rationale section for § 2753(b) in 
this section B of this chapter.  
§ 2754(d) [newly proposed subsection]  
Purpose. The Proposed Amendments add a new subsection 2754(d) that requires all 
applicants to provide hot soak plus diurnal emission test data for the engine or equipment model in the evaporative family that is expected to exhibit the highest  hot 
soak plus diurnal emission rate relative to the applicable hot soak plus diurnal emission standard , in accordance with TP -902, for MY  2024 and subsequent model years. The 
purpose of this change is to ensure that all engines certified will meet the pro posed, 
more stringent evaporative emission standards for SORE.  
Rationale . This new subsection is necessary to implement the proposed, more 
stringent evaporative emission standards for MY  2024 and subsequent model years. 
The rationale for this change is the same as that for the change proposed for 
§ 2753(c), described earlier in this section B of this chapter.  
§ 2754(d) [re- lettered to (e)]  
Purpose. The Proposed Amendments change the list lettering of the current 
subsection (d) to (e) to provide sequential lettering of the subsections.  
Rationale . This change is necessary because the Proposed Amendments add a new 
subsection 2754(d).  
§ 2754(e) [re- lettered to (f)]  
Purpose. The current regulations in this section  set requirements  for SORE  fuel line 
testing  for MY 2020  and subsequent  model  years  in accordance  with the Fuel Line 
Assembly  Tensile Test in section  5.4 of ANSI/OPEI  B71.10- 2013 to ensure fuel lines are 
securely  connected  to prevent  fuel leakage . There are four Proposed  Amendments  to 
this section:  
• The first changes the subsection list lettering from  (e) to (f) to provide 
sequential lettering of the subsections;  
• The second amends the text to specify the fuel line testing requirements per 
ANSI/OPEI B71.10 -2013  will apply only through MY  2023;   
228 • The third deletes the text  that follows the reference to ANSI/OPEI B71.10 -2013, 
“, which is incorporated by reference herein ;” and 
• The fourth adds text to allow applicants the option to conduct testing in 
accordance with the F uel line connection tensile test in section 5.5 of 
ANSI/OPEI B71.10 -2018 . 
Rationale. The rationales  for the Proposed  Amendments to § 2754(e)  are as follows:  
• The change to the subsection list lettering is necessary because the Proposed Amendments add a new subsection 2754(d).  
• The change to apply the requirement to test according to ANSI/OPEI B71.10- 2013 only through MY  2023 is necessary because a more recent version 
of the test is available. Industry requested that CARB reference the most recent version,  given manufacturers typically use the most recent editions of standards 
documents in addition to any earlier editions required by regulations. CARB staff evaluated the differences between the two editions and determined that 
the 2018 edition do es not relax  any standards or testing procedures and 
therefore is an appropriate replacement for the 2013 edition. The changes to the Fuel line connection tensile test in the 2018 edition versus the 2013 edition 
were editorial or provided clarification of the existing  requirements. An 
informative Annex A included in the 2018 edition that provided rationales for 
changes did not mention any changes to the Fuel line connection tensile test.  
• The deletion of the text, “which is incorporated by reference herein,” is necessar y to prevent redundancy, given the definition provided in § 2752(a)(2) 
already states that this document is incorporated by reference.  
• The addition of text to allow applicants the option to test in accordance with 
either ANSI/OPEI B71.10 -2018 or ANSI/OPEI B71.10- 2013 is necessary to allow 
flexibility for manufacturers for earlier model years (e.g., MYs 2022 and 2023) 
with design and testing already underway.  
§ 2754(g) [newly proposed subsection]  
Purpose. The Proposed Amendments add a new subsection 2754(g) that requires all 
applicants to conduct f uel line assembly testing in accordance with the F uel line 
connection tensile test in section 5.5 of ANSI/OPEI B71.10- 2018 for MY 2024 and 
subsequent model years to ensure fuel lines are securely co nnected to preven t fuel 
leakage and associated evaporative emissions.  
Rationale . This change is necessary because a more recent version of the test is 
available. Industry requested that CARB reference the most recent version, given 
manufacturers typically use the most rece nt editions of standards documents in 
addition to any earlier editions required by regulations. CARB staff evaluated the 
differences between the 2013 and 2018 editions and determined that the 2018 edition 
does not relax any  standards or testing procedures and therefore is an appropriate 
replacement for the 2013 edition.  The changes to the Fuel line connection tensile test  
229 in the 2018 edition versus the 2013 edition were editorial or provided clarification of 
the existing requirements. An informative Annex A  included in the 2018 edition that 
provided rationales for changes did not mention the changes to the Fuel line connection tensile test.  
§ 2754(h) [newly proposed subsection]  
Purpose. The Proposed Amendments add a new subsection 2754(h) that requires an 
applicant certifying SORE  to comply with the proposed hot soak plus diurnal emission 
standards to submit a determination that running loss emissions are controlled from 
being emitted to the atmosphere. The proposed determination requires approval from the Ex ecutive Officer unless actively- purged carbon canisters meeting the 
requirements of the regulations  are used . The Proposed Amendments require testing 
in accordance with the procedures specified in TP -902 §  2.4, which are newly added 
by the Proposed Amendments. The purpose of the Proposed Amendments to § 2754(h) and TP -902 is to better ensure that all manufacturers are meeting the 
requirement that running loss evaporative emissions be controlled.  
Rationale . This addition is necessary for consistency with the new testing requirements 
proposed for TP -902 § 2.4, which are described in section D of this chapter. Adding a 
procedure to demonstrate that running loss evaporative emissions are controlled from 
being emitted into the atmosphere  will give manufacturers c ertainty regarding the 
method to use for such demonstrations.  
§ 2754.1. Certification Averaging, Banking, and Trading  
Purpose. Both exhaust and evaporative emission regulations currently include 
provisions for certification averaging, banking, and trading programs, also called 
emission reduction credit programs. The emission reduction credit programs allow 
manufacturers to generate credits when they produce SORE that emit at levels lower 
than the current emission standards. These credits may be used to offset emissions from SORE that emit at higher levels, banked for future years, or traded with other 
manufacturers. Section  2754.1 provides the requirements for manufacturers’ 
participation in the voluntary certification averaging and banking program for SORE 
with complete evaporative emission control systems certified to the  evaporative 
emissions standards specified in § 2754(a) or § 2757. The Proposed Amendments 
change the title of this section from, “Certification Averaging and Banking” to “Certification Ave raging, Banking, and Trading,” and change all references to 
“averaging and banking” in this section to “averaging, banking, and trading.” These 
changes reflect the new trading provisions proposed for the section.  
Rationale . This change is necessary to prov ide clarity and consistency with the 
proposed new trading provisions described in the new subsection 2754.1(e).   
230 § 2754.1(b)(3)  
Purpose. The current regulations in § 2754.1(b)(3) specify that a  manufacturer cannot 
include in its calculation of credit generation any new engines or equipment not 
subject to this Article . As specified in § 2750(a) and §  2751(c), the evaporative 
emission standards apply to gasoline- fueled, spark -ignit ion small off -road engines 
rated at less than  or equal to  19 Kilowatts, and equipment utilizing such engines, and 
do not apply to engines or equipment that use compression- ignition engines, or 
engines or equipment powered with CNG, propane, liquefied petroleum gas (LPG),  or 
liquefied natural gas (LNG) (collectively, “alternative fuel s”). The Proposed 
Amendments add new text to § 2754.1(b)(3) that allows SORE powered by these 
alternative fuels to be certified for evaporative emission credits.  
Rationale . This change is necessary to incentivize the manufacture of low -emission 
engines as the market for ZEE continues to develop further. Current regulations do 
not require manufacturers to certify the evaporative emission control system of 
engines powered by alternative fuels because the alternative fuels are contained in 
sealed, pressurized  tanks that prevent evaporative emissions. The proposed change 
would provide more flexibility in the credit program by allowing manufacturers to 
certify and generate credits for more engines. This change could provide both public health benefits and econom ic benefits for manufacturers. Accrual of additional 
emission reduction credits would lessen the initial cost impacts for manufacturers (and those purchasing equipment) that could result as ZEE increasingly accounts for a greater portion of equipment sales —spread out the cost impact over a longer time —
by allowing manufacturers to produce and sell SORE and equipment powered by 
alternative fuels for longer.  At the same time, incentivizing manufacturers to produce 
more alternative fuel -powered equipment rather  than gasoline- powered equipment 
would enable more rapid reductions in SORE emissions and associated adverse health 
impacts in California . The credits earned for these alternative fuel -powered engines 
will allow manufacturers more flexibility in planning e ngine sales to meet California 
market demand . 
§ 2754.1(b)(5)  
Purpose. The current regulations in this section specify: “ A Holder  shall certify an 
evaporative family to an  EMEL and shall determine an EFELD .” Per §  2752(a)(13) 
[re-numbered to (15) in Appendix B], the Holder is “the person to whom the Executive 
Order of Certification is issued. ” The EFELD is calculated  by a Holder  and can be 
positive or negative subject to the limitation s in subsections (b)(6) and (b)(7) of this 
section, provided the sum of the Holder’s  projected balance of  credits from all credit 
transactions for each engine class in a given model year is greater than or equal to 
zero, as determined under subsection (e) .…” The phrase “for each engine class” in the 
regulations specifies that all evaporative emission credits must be used within the 
same engine class in which they are generated. The Proposed Amendments remove 
this requirement by deleting the phrase, “for each engine class,” in order to provide 
additional flexibility for cre dit usage. This proposed change would not impact overall  
231 emission reduction benefits (i.e., it would not result in excess emissions) because the 
proposed change does not alter the current requirement in § 2754.1(e) (2) 
[§ 2754.1( f)(2) in the Proposed Amendm ents] that the sum of positive and negative 
emission credits a manufacturer holds  be greater than or equal to zero.  
The Proposed Amendments also change the referenced subsection from “subsection (e)” to “subsection (f)” to accommodate the addition of a newly proposed 
subsection 2754.1(e) and maintain sequential section numbering.  
Rationale . This removal of the text “fo r each engine class” is necessary to incentivize 
the manufacture of low emission engines and ZEE as the market for ZEE develops 
further. The flexibility to use evaporative emission credits across all engine classes will 
allow manufacturers more flexibility  in planning engine sales to meet California market 
demand , while also meeting the applicable evaporative emission standards for SORE 
equipment. The total emissions from credit usage would remain the same, but 
manufacturers would be able to use the credits generated by one engine class for 
engines in other classes without the requirement to maintain a balance of credits that is greater than or equal to zero in each engine class. This flexibility would facilitate compliance with the averaging, banking, and trading provisions when the emission standards are zero for most SORE and more stringent for generator engines for 
MY 2024. The current diurnal emission standards depend on the fuel tank nominal 
capacity ( the volume of fuel indicated by the manufacturer that represents the 
maximum recommended fill level , as defined in § 2752). This results in the diurnal 
emission standard for an engine with greater fuel tank nominal capacity being higher than for an engine with smaller fuel tank nominal capacity. For example, a model using 
an engine with displacement greater than or equal to 225 cc (Class II) with a 120- liter 
(32-gallon) nominal capacity would have a diurnal emission standard of approximately 
8 grams per day. Such a model could have an EMEL of 24 grams per day, which is 
24 times the diurnal emission standard for a walk -behind lawn mower with a Class I 
engine. Requiring the balance of credits from all credit transactions for each engine 
class in a given model year to be greater than or equal to zero has been im portant to 
ensure that emission reductions of one class of engine do not result in overall higher emissions of engines in other classes. For example, if Class I walk -behind lawn mower 
engines had emissions below the emission standards and the credits gener ated by 
those engines were used to offset higher emissions from Class II generator engines, 
consumer s might be unable to find low -emitting generators . Such potential problems 
would be mitigated under the Proposed Amendments by the increased availability of  
ZEE, the reduction in the maximum EM ELs in §§ 2754.1 (b)(6)  and (7) , and the 
implementation of more stringent emission standards. The more stringent emission 
standards in the Proposed Amendments would reduce the possibility of extremely 
high-emitting engines being introduced into California commerce. The proposed 
emission standards also may result in manufacturers deciding to phase out high-
emitting models or entire classes of engines if it is less profitable to produce such engines than to produce different models or classes of engines. For example, a 
manufacturer could determine that using credits to offset emissions from a high - 
232 emitting handheld engine that would be installed in a low -cost piece of equipment 
(e.g., a string trimmer with a retail price of $70) would be less profitable than using 
those credits to offset emissions from an engine that would be installed in a riding 
lawn mower with a retail price of $15,000.  
Changing the letter of the subsection reference is necessary to provide consistent 
lettering and to prevent confusion for the reader.  
§§ 2754.1(b)(6) and (b)(7)  
Purpose. The Proposed Amendments would establish new EMELs for all SORE 
equipment beginning with MY  2024. As defined by § 2752(a)(9) [§ 2752(a)(11) in the 
Proposed Amendments], an EM EL is the evaporative emission rate declared by the 
manufacturer for a model within an evaporative family. The declared rate must be 
based on evaporative emissions test results for the model of engine or equipment 
within the evaporative family that is expe cted to exhibit the highest diurnal 
evaporative emission rate relative to the applicable diurnal or hot soak plus diurnal emission standard, obtained by following TP -902. The current regulations in §§ 
2754.1(b)(6) and (b)(7)  set EMELs that are a multiple of the current emission standard: 
1.5 times the emission standard for walk -behind mowers and 3 times the emission 
standard for other equipment. The Proposed Amendments set EMELs for MY  2024 
and subsequent model years equal to 1.5  grams organic material hydrocarbon 
equivalent per test for walk -behind mowers, and 2.1 grams organic material 
hydrocarbon equivalent per test  for other equipment.  
Rationale . This change is necessary because the Proposed Amendments set emission 
standards to zero for all equipment beginning with MY  2024, which would result in an 
EMEL of zero if the regulations are not changed. An EMEL of zero would prevent manufacturers from being allowed to use the credits they have generated, which would defeat the purpose of the emission reduction c redit program. Establishing more 
stringent EMELs is necessary to accelerate evaporative emission reductions in order to 
achieve the necessary SORE emission reductions by 2031 as expected under the 2016 
State SIP Strategy.  The proposed maximum EMEL for MY  2024 and subsequent model 
year walk -behind lawn mowers is numerically equivalent to the current maximum EMEL 
for diurnal emissions. However, the proposed maximum EMEL includes hot soak 
emissions. The proposed maximum EMEL for engines or equipment other than walk-
behind lawn mowers is three times the proposed hot soak plus diurnal emission 
standard for generator engines with displacement greater than or equal to 225 cc. This would allow for evaporative emissions from generator engines with displacement 
greate r than or equal to 225 cc to be up to three times the applicable emission 
standard, comparable to the current requirements.  Engines that are currently certified 
to EMELs higher than the proposed maximum EMELs could not be certified for 
introduction into Ca lifornia commerce for MY 2024 or subsequent model years unless 
their emissions were reduced. This will ensure the highest -emitting engines, which 
have the greatest impact on air quality and expose operators to the greatest amounts  
233 of pollutants, are the first to have their emission levels reduced or be replaced with 
lower -emitting engines or ZEE.  These EMELs will allow manufacturers to use the 
credits they have generated, while preventing the introduction for sale or lease for use in California of new SORE with excessive evaporative emissions.  
§§ 2754.1(c) and (d)  
Purpose. Section  2754.1(c)  specifies provisions  for averaging  of credits,  and 
§ 2754.1(d)  specifies provisions  for banking of credits.  The Proposed  Amendments 
include two types  of changes to provid e consistency  with the addition  of a newly 
proposed  subsection 2754.1(e)  for trading  provisions:  
• The Proposed Amendments change the reference  to “subsection (e) (2)” in 
§ 2754.1(c)(1) to “subsection (f) (2),” and change the reference to 
“subsection (e)(1) ” in § 2754.1(d)(1) to “subsection (f) (1),” to accommodate the 
addition of a new ly proposed  subsection 2754.1(e)  for trading provisions  and 
maintain sequential section numbering.   
• The Proposed Amendments add text to §§ 2754.1(c)(2), (d)(1), (d)(2), and  (d)(3) 
to allow the use of credits obtained through trading to reflect the proposed 
addition of trading to the credit provisions specified in the newly proposed subsection 2754.1(e).  
Rationale . The first type of change, changing the letter of the subsection references, is 
necessary to provide  consistent lettering and to prevent confusion for the reader. The 
second type of change is necessary to enable manufacturers to use credits obta ined 
through trading per the proposed provisions specified in the newly proposed 
subsection 2754.1(e).  
§ 2754.1(e) [newly proposed subsection]  
Purpose. The current evaporative emission regulations contained in § 2754.1 allow 
only averaging and banking of evaporative emission credits. The Proposed 
Amendments add a new subsection 2754.1(e) that expands the credit program to 
allow trading of evaporative emission credits. The newly proposed 
subsection 2754.1(e) provides requirements for the exchange of evaporative emission 
credits between engine manufacturers and the use of traded credits for averaging and 
banking. The proposed trading requirements align with existing trading requirements in the exhaust regulations, which are designed to prevent potential excess emissions that could result from inappropriate use of credits.  
Rationale . This change is necessary to further incentivize the manufacture of low -
emission engines and ZEE and to provide consistency with the exhaust emission regulations. This change will allow more flexibility in the emission reduction credit program and enable manufacturers who are able to earn evaporative emission credits to trade them to manufacturers who cannot, encouraging them to make the lowest-
emitting engines possible. This change could provide both public health benefits and 
economic benefits for manufacturers. Accrual of additional emission reduction credits  
234 would lessen the initial cost impacts for manufacturers (and those purchasing 
equipment) that could result as ZEE increasing ly accounts for a greater portion of 
equipment sales— spread out the cost impact over a longer time —by allowing 
manufacturers to produce and sell SORE and low -emission engines for longer.  At the 
same time, incentivizing manufacturers to produce more low -emission engines and 
ZEE that could generate evaporative emission credits that could in turn be traded to 
other manufacturers would enable more rapid reductions in SORE emissions and 
associated adverse health impacts in California. Furthermore, aligning the p roposed 
trading requirements for evaporative emission credits with the existing requirements for exhaust emission credit trading makes them more easily understood by 
participants in the credit market, and better ensures their effectiveness in preventing 
any excess emissions to result from evaporative emission credit trading.  
§ 2754.1(e)(1) [re- lettered to (f)(1)]  
Purpose. The Proposed Amendments change the subsection list lettering of the 
current subsection (e) to (f) to provide sequential lettering of the subsections, and 
change the reference for the definition of Production Volume from § 2752(a)(21 ) to 
§ 2752(a)( 25). In addition, the Proposed Amendments delete the requirement for 
emission credit calculation results to be rounded to the nearest tenth of a g ram. 
Rationale . The first two changes are necessary because the Proposed Amendments 
add a new subsection 2754.1(e), and new definitions in § 2752(a), which result in the 
need to update subsection lettering and references. The third change is necessary to 
provide consistency with the Proposed Amendments to § 2754(a). The current 
requirement to round credit calculation results to the nearest tenth of a gram will not 
provide an adequate number of significant digits to comply with the second 
requirement in this  subsection, “Consistent units with two significant digits are to be 
used throughout the equations,” once the proposed evaporative emission standard of 
0.00 grams of organic material hydrocarbon equivalent per test becomes effective.  
§ 2754.1(f) [re- lettered to (g)]  
Purpose. The Proposed Amendments change the subsection list lettering of the 
current subsection (f) to (g) to provide sequential lettering of the subsections. The Proposed Amendments also change references to § 2754.1( e) and § 2754.1(f)  within 
the subsection to § 2754.1(f) and § 2754.1( g) to reflect the updated lettering in the 
Proposed Amendments.  
Rationale . These changes are necessary because the Proposed Amendments add a 
new subsection 2754.1(e).  
§ 2754.1(g) [re- lettered to (h)]  
Purpose. The current regulations in § 2754(g) describe requirements for records 
maintenance by Holders of Executive Orders of Certification (Holders). The Proposed Amendments change the subsection list lettering of the current subsection (g) to (h) to  
235 provide sequential lettering of the subsections. The Proposed Amendments also add 
requirements for the maintenance of records for Holders participating in credit trading 
as a newly proposed subsection 2754.1(h)(2). The proposed records maintenance 
requirements  align with existing trading records maintenance requirements in the 
exhaust regulations. The Proposed Amendments change the subsection list numbering 
for the current subsections (2) through (5), to (3) through (6), respectively, to provide 
sequential numb ering.  
Rationale . The changes to subsection lettering and numbering are necessary because 
the Proposed Amendments add new subsections as §  2754.1(e) and § 2754.1(h)(2). 
The addition of records maintenance requirements for credit trading is necessary for CARB to be able to verify credit balances for participants and ensure no excess 
emissions result from credit trading, and to provide consistency with the exhaust 
emission regulations. Aligning the proposed evaporative emission credit trading record maintena nce requirements with the existing requirements for exhaust emission 
credit trading makes them more easily understood by participants in the credit market, and better ensures their effectiveness in preventing any excess emissions to result from evaporative  emission credit trading.  
§ 2754.1(h)  
Purpose. The current regulations in § 2754.1(h)  describe  requirements  for participants  
in the credit program for end-of-year and final reports.  There are seven proposed  
amendments  to this section  that were  not already  described  in the “Global  
Amendments”  section  of this chapter:  
• The first changes the subsection list lettering of the current subsection (h) to (i) 
to provide sequential lettering of the subsections (the remainder of this summary uses the updated lettering );  
• The second changes the reference to subsection (e) to subsection (f) in § 2754.1(i)(1);  
• The third adds newly proposed text to § 2754.1(i)(1) that requires c opies of 
contracts related to credit trading to be included or supplied by the broker, if 
applicable ; 
• The fourth deletes from § 2754.1(i)(1) the requirement that the report show that 
the credit summation for each class of engines or equipment is equal to or greater than zero;  
• The fifth changes the reference for the definition of Production Volume in 
§ 2754.1(i)(2) from § 2752(a)(21) to § 2752(a)(25) ; and  
• The sixth corrects a mistake made when the credit program requirements were adopted, where the text in § 2754.1(i)(6) mistakenly states that errors in 
previously submitted reports “may” be corrected in  the final report, by 
changing “may” to “must.”   
236 • The seventh corrects a second mistake, where the text in § 2754.1(h)(7) 
(re-lettered to (i)(7)) mistakenly states that e rroneous positive credits will be 
void except as provided  in “subsection (h)” of this section  instead of in 
“subsection (f) .” Subsection  (f) (re -lettered to (g) by the Proposed Amendments) 
specifies the provisions for certification using credits. To fix this error, the 
Proposed Amendments change the exception reference to “except as provided  
in subsection (g) of this section.”  
Rationale. The rationales  for the Proposed  Amendments to § 2754.1(i)  are as follows:  
• The first, second, and fifth changes are necessary because the Proposed 
Amendments add a new subsection 2754.1(e), and new definitions in §  2752(a), 
which result in the need to update subsequent subsection lettering and 
references.  
• The third change, to require c opies of contracts related to credit trading , is 
necessary for CARB to be able to verify compliance with all credit trading provisions and provides consistency with reporting requirements in the exhaust 
emission regulations. Compliance with all provisions is necessary to ensure no excess emissions result from implementation of the credit program.  
• The fourth change, to delete the requirement that the credit summation for each class be equal to or greater than zero, is necessary for consistency with the proposed change to § 2754.1(b)(5) , which removes the requirement for 
evaporative emission credits to be used within the same engine class in which they are generated. Under the Proposed Amendments, there is no longer a 
regulatory need for credit program participants to provide the summations by 
class.  
• The sixth change, to change “may” to “must,” is nec essary to ensure correct 
reporting, which in turn is necessary to ensure no excess emissions result from implementation of the credit program.  
• The seventh change, to change the exception reference from subsection (h) to (g), is necessary to provide clarity necessary to help ensure the correct 
regulation  is referenced by manufacturers .  
§ 2754.3. Evaporative Emission Reduction Credits – Zero-Emission Generator 
Credits Averaging, Banking, and Trading Provisions  [newly 
proposed section]  
Purpose. The Proposed Amendments add a new subsection 2754.3 to establish a new, 
generator -specific evaporative emission reduction credit program.  This voluntary 
program would allow manufacturers to offset emissions from generators with emission 
levels above the proposed evaporative emission standards by using credits earned by  
zero- emission generators. All SORE, including generator engines, may be included in 
engine families participating in the  certification  averaging, banking and trading 
program described in § 2754.1. The evaporative emission regulations, however, do  
237 not include a zero -emission equipment credits averaging, banking and trading 
program. The emission inventory calculated with SORE2020 indicates that generators 
produce the highest statewide emissions of any small off -road equipment type. In 
2020, g enerators accounted  for approximately 14 percent of the total population of 
SORE equipment, and 19 percent of all ROG and  NO x emissions from SORE (CARB, 
2020).  
The Proposed Amendments add a new emission reduction cr edit program for zero -
emission generators to incentivize further development of the market. The program is 
tiered, granting more emission reduction credits for zero- emission generators with 
greater energy storage and power delivery than for those with less  energy storage and 
power delivery. The purpose of the tier system is to provide the greatest credit benefits to manufacturers who develop zero -emission generators in the least 
developed sector of the market (i.e., zero -emission generators with the greatest 
energy storage and highest power output). The proposed zero -emission generator 
credits would be subject to similar provisions to those in the existing emission reduction credit programs, including a five -year limit on banking credits.  
Rationale . This change is necessary to incentivize manufacturers to increase 
development and production of zero -emission generators, particularly zero -emission 
generators with the greatest energy storage and highest power output. Currently, the availability of zero -emission generators is limited and their price is often more than 
that of a comparable SORE generator. This credit program aims to decrease the price of zero- emission generators while allowing increased flexibility for manufacturers of 
SORE generators as more model s of zero- emission generators enter the market . 
§ 2754.3(a)  
Purpose. The Proposed Amendments define the applicability of the zero -emission 
generator evaporative credit program. The Proposed Amendments specify the program requirements are applica ble to all zero- emission generators as defined in 
§ 2408.2 produced in MYs 2022 through 2026. The Proposed Amendments establish 
that participation is voluntary, but if a manufacturer elects to participate, it must follow all provisions set forth in § 2754.3.  
Rational e. This section is necessary to define which manufacturers are eligible to 
participate in the program to prevent confusion. Including a reference to § 2408.2(a) , 
rather than restating its contents, prevents unnecessary redundancy in the regulations. The Proposed Amendments add a new subsection 2408.2, “Exhaust Emission 
Reduction Credits – Zero- Emission Generator Credits Averaging, Banking, and Trading 
Provisions ”, with applicability defined in §  2408.2(a). Similar to §  2754.3(a), §  2408.2(a) 
specifies the c redit program applies to zero- emission generators produced in 
MYs 2022 through 2026. The rationale for § 2754.3(a)  is the same as the rationale for 
§ 2408.2, provided in section A of this chapter. The ability to earn zero -emission 
generator credits extends through MY 2026 to incentivize further development of the zero- emission generator market sooner. No zero -emission generator credits may be  
238 earned for MY 2027 to ensure that manufacturers introduce new models of zero -
emission generators with greater energy storage and higher power output earlier. This 
limitation on earning zero -emission generator credits will also ensure that banked 
zero- emission generator credits are used by the end of MY 2031 thereby providing a 
known timeline for the use of credits. 
§§ 2754.3(b)(1) through (b)(3)  
Purpose. The Proposed  Amendments establish two general  provisions  for the 
generation and use of zero- emission generator  credits:  
• The first specifies that z ero-emission generator evaporative credits may be used 
to offset emissions for an evaporative family used exclusively in generators.   
• The second explicitly states that a manufacturer of engine families certified for 
zero- emission generator credits under §  2408.2 may generate zero -emission 
generator evaporative credits. S ubsections of this provision also establish 
requirements for credit generation:  
o The first subsection specifies that a manufacturer of zero -emission 
generator engine families certified for zero -emission generator credits 
under §  2408.2 shall earn zero -emission generator evaporative credits in 
accordance with the proposed Table 1 in this § 2754.3 for averaging, 
banking, or trading, or a combination thereof. Table  1 establishes z ero-
emission generator energy, power and useful life  requirements for 
different levels (aka “tiers”) of credit eligibility, that grants more emission 
reduction credits for larger zero -emission generators (those with greater 
energy storage  and higher power output).  
o The second subsection specifies that manufacturers must demonstrate compliance under the averaging, banking, and trading provisions of this § 2754.3 for a particular model year within 270 days after the end of the 
model year.  
Rationale . These provisions are necessary to ensure no excess emissions result from 
implementation of the credit program and to ensure the credit program accomplishes 
the goals specific to generators. The first provision specifies z ero-emission generator 
evaporative credits may be used to offset emissions for an evaporative family used 
exclusively in generators in order to further incentivize development of the zero -
emission generator market. As described in section D.2 of  Chapter  I, there is still a 
need for innovation and growth in the zero -emission generator market, particularly for 
zero- emission generators with the greatest energy storage and highest power output . 
Implementation of zero -emission standards for generators sooner than MY 2028 could 
have unintended negative impacts on power supply in some regions of California . The 
Proposed Amendments add a generator -specific credit program to increase flexibility 
for manufacturers and reduce cost impacts of the proposed req uirements to 
accelerate the deployment of ZEE. Limiting credit use to offsetting emissions from generator engines is necessary to help ensure those benefits for manufacturers also  
239 work towards addressing the public’s need for reliable and affordable power supply . 
Using credits earned by zero -emission generators to offset emissions from generator  
engines will ensure that the benefits of the credits are used toward the continued 
availability of SORE generators as the market for zero -emission generators continues 
to mature. Use of zero -emission generator credits for other equipment types c ould 
limit options for California consumers to use SORE generators in situations where an 
appropriate zero -emission generator may not yet be available or cost- effective as the  
market matures . 
The proposed Table  1 establishes a tiered credit eligibility approach that is necessary 
to incentivize manufacturers to develop additional zero -emission generators in the 
least developed sector of the market: zero -emission generators with the greatest 
energy storage and highest power output. The program would award a greater 
amount of credits to zero -emission generators that store more energy or produce 
more power. The credit eligibility ranges from 0.5 g organic material hydrocarbon 
equivalent·day-1 or 0.5 g organic material hydrocarbon equivalent·test-1 credits for a 
Level 1  or 2 zero- emission generator to 0.6 g organic material hydrocarbon 
equivalent·day-1 or 0.5 g organic material hydrocarbon equivalent·test-1 credits for a 
Level 3 or 4 zero- emission generator. The credits generated by a zero -emission 
generator could offset either a portion or all of the emissions from a generator engine, 
depending on the emission level  and displacement of the generator engine.  The 
power requirements for Levels 1 through 4 in Table 1 are the same as proposed for exhaust credit eligibility in §  2408.2 (b). This consistency is necessary to make the 
requirements easier to understand and prevent confusion and additional administrative work for manufacturers, which in turn helps facilitate participation in the credit program and accelerate the further development of the zero -emission 
generator market.  
The proposed Table  1 specifies a minimum requirement for generator “useful life” of 
5 years to be eligible for credit generation, whereas § 2408.2 (b) specifies a minimum 
requirement for “durability period” of 500  hours. Both requirements are necessary for 
the same reason: to incentivize manufacturers to develop zero -emission generators 
that address the public’s need for reliable power supply . The requirement for 
evaporative credit generation is in terms of useful life and years for consistency with the existing useful life requirements for evaporative emissions for engines in § 
1054.110 and § 1054.112.  Zero- emission generators certified to earn both exhaust and 
evaporative credits would therefore be required to meet the applicable requirements for 500 hours of operation and 5 years.  
The requirement for manufacturers to demonstrate complian ce under the averaging, 
banking, and trading provisions of this § 2754.3 for a particular model year within 
270 days after the end of the model year is consistent with requirements for existing 
credit programs  and the proposed generator -specific exhaust cr edit program. This 
requirement is necessary for CARB to be able to verify compliance with program  
240 requirements, which is necessary to prevent  potential inappropriate accrual and 
subsequent use of credits that could lead to excess emissions.  
§ 2754.3(c)  
Purpose . The Proposed  Amendments establish averaging  requirements that: 
• Allow 100  percent of negative credits from engine families with EMELs above 
the applicable emission standard to be offset by positive zero -emission 
generator credits; and  
• Allow zero -emission generator credits used in averaging for a given model year 
to be obtained from zero -emission generator evaporative credits banked in 
previous model years, or zero -emission generator evaporative credits of 
previous model years obtained through trading.  
Rationale . These averaging requirements are necessary to support the key goals of the 
zero- emission generator credit program: allow manufacturers flexibility, while reducing 
emissions from generators and accelerating market development of zero -emission 
generator options in advance of emission standards of zero for all generators for MY 
2028 and subsequent model years. Allowing all excess emissions to be offset by 
zero- emission generator credits is necessary to provide manufacturers flexibility to 
produce SO RE generators that may emit at levels higher than the more stringent MY 
2024- 2027 emission standards as the market for zero -emission generators develops 
further . This flexibility is warranted as it supports the goal of encouraging 
manufacturers to produce more zero -emission generators. These proposed averaging 
requirements are consistent with existing requirements and proposed amendments for 
existing credit programs.  
§ 2754.3(d)  
Purpose. The Proposed  Amendments establish provisions  for banking  that: 
• Beginn ing with MY  2022, allow manufacturers to bank zero -emission generator 
evaporative credits for use in subsequent model years for the purposes of 
averaging and trading ; 
• Allow manufacturers to bank credits only after submission of all final reports and 
verifi cation of the reporting by CARB;  
• Require that, during the model year, and before submittal of the end -of-year 
report, credits originally designated in the certification process for banking will be considered reserved, and may be re- designated for trading i n the end -of-
year report and final report;  
• Allow zero -emission generator credits to  be banked for up to five years; 
• Require zero- emission generator credits that are unused after five years to 
expire, and no longer allow these expired credits to be used tow ard offsetting 
negative evaporative  emission credits from other eligible evaporative  families.  
241 Rationale . These provisions are necessary to ensure that any banked credits are 
calculated correctly and use of banked credits in future years does not result in  excess 
emissions. The five- year expiration date for credits prevents credits from being banked 
indefinitely and provides a known timeline for all new generators sold or leased for use 
in California to be zero- emission generators. These proposed banking requirements 
are consistent with requirements for existing credit programs and the proposed 
generator -specific exhaust emissions credit program.  
§ 2754.3(e)  
Purpose. The Proposed  Amendments establish provisions  for trading  that: 
• Allow a Holder to exchange zero- emission generator credits with other Holders 
in trading;  
• Allow zero -emission generator credits banked in previous years to be used for 
trading; and  
• Allow traded zero -emission generator credits to be used for averaging or 
banking for up to five years from the time of zero -emission generator credit 
generation.  
Rationale . The first two provisions are necessary to enable flexibility for manufacturers, 
which supports one of the goals of this credit program: lessen the initial cost impacts 
for manufacturers  (and those purchasing equipment) that could result while the zero -
emission generators market develops further. The five- year expiration date from the 
time of credit generation  is necessary to prevent credits from being traded and 
banked indefinitely, which is necessary to prevent excess emissions, and to provide a known timeline for all new generators sold or leased for use in California to be zero- emission generators. These proposed trading requirements are consistent with 
requirements for existing credit  programs  and the proposed generator -specific 
exhaust emissions credit program.  This consistency is necessary to prevent confusion, 
calculation errors, and costs of additional manufacturer time spent on learning and maintaining different methods and resolv ing errors.  
§ 2754.3(f)  
Purpose. The Proposed  Amendments provide  an equation,  steps,  and definitions 
required  to calculate  zero-emission generator evaporative  credits  and assess  
manufacturer compliance  with emission standards.  For calculating  the total credits  
earned  for a zero- emission generator evaporative  family,  the credits  indicated  in 
Table  1 in subsection (b) are multiplied by the sales  of that family.  The Proposed  
Amendments reference  the proposed  § 2408.2  for the definition of “sales,”  and 
§ 2408.2(f) references  the existing  definition of sales  provided  in § 2401.  
Section  2401(a)(37)  [to be amended  to (42)] defines sales  as follows:  
““Sales” or “Eligible sales”  means the actual  or calculated  sales  of an engine 
family in California for the purposes  of averaging,  banking or trading.  Upon  
Executive  Officer  approval,  an engine manufacturer may calculate  its eligible  
242 sales through market analysis of actual  federal  production  or sales volume.  … 
Actual  sales are sales calculated  at the end of a model  year b ased  on that 
model  year’s  production,  rather than on estimates  of production.”  
Section  2408.2( f) also specifies that annual sales projections are used to project credit 
availability for initial certification , and act ual sales volume is used in determining actual 
credits for end -of-year compliance determination.   
Rational e. An equation with detailed steps and definitions is necessary to ensure 
consistency and provide a fair and equitable process for all manufacturers that choose 
to participate in the credit program. In addition, such consistency is necessary to 
ensure use of credits does not result in excess emissions. The proposed equation and steps are consistent with requirements for existing credit programs  and the proposed 
generator -specific exhaust emissions credit program. This consistency is necessary to 
prevent confusion, calculation errors, and costs of additional manufacturer time spent on learning and maintaining different methods and resolving errors.  
§ 2754.3(g)  
The Proposed  Amendments specify  requirements for certification  using  zero- emission  
generator  evaporative  credits  that: 
• Identify the specific materials that must be submitted in the certification 
application by a manufacturer using zero -emission generator evaporative 
credits, and allows inf ormation required by §§  2754.3(g)(1)(B), 2754.3(g)(1)(C), 
and 2 754.3(g)(1)(D) to be supplied in an electronic spreadsheet;  
• Establish a ll Executive Orders of Certification  issued are conditional upon 
manufacturer compliance with the provisions of this § 2 754.3 both during and 
after the model year of production , and f ailure to comply with all provisions of 
this section  will be considered to be a failure to satisfy the conditions upon 
which the Executive Order of Certification  was issued ; and  
• Require the manufacturer to bear the burden of establishing to the satisfaction 
of the Executive Officer that the conditions upon which the Executive Order of Certification was issued were satisfied or waived . 
Rationale . These requirements are necessary to ensure prop er documentation of 
zero- emission generator evaporative credit use in certification applications, which is 
necessary for CARB to ensure compliance with program requirements and to prevent 
excess emissions from the improper use of credits. The proposed requirements are 
consistent with requirements for existing credit programs  and the proposed zero -
emission generator exhaust emission reduction credit program.  This consistency is 
necessary to prevent confusion, errors, and costs of additional manufacturer time 
spent on learning and maintaining different methods and resolving errors.   
243 §§ 2754.3(h) and (i)  
Purpose. The Proposed Amendments specify detailed records maintenance 
requirements in § 2754.3 (h) and requirements for end -of-year and final reports in 
§ 2754.3(i). The actions required in these subsections for the proposed zero -emission 
generator evaporative emission reduction credit program are identical to actions 
required by existing credit programs.  
Rationale . The addition of records maintenance and reporting requirements is 
necessary for CARB to be able to verify credit balances for participants and their compliance with emission standards, and to ensure no excess emissions result from credit use. Aligning the proposed records maintenance and reporting requi rements 
with the requirements for other credit programs makes them more easily understood 
by participants in the credit market, and better ensures their effectiveness in 
preventing any excess emissions resulting from credit use.  
§ 2755. Permeation Emission  Standards  
Purpose. The current regulations in § 2755 establish permeation emission standards 
for fuel tanks and fuel lines in SORE with displacement less than or equal to 80 cc. 
These emission standards are referenced by § 2753(c) as one of two options fo r 
certification of an evaporative emission control system in SORE with displacement less than or equal to 80 cc. The current regulations do not specify an end date for the 
applicability of the emission standards, and therefore the requirements currently ap ply 
to all model years subsequent to the “effective date model year” specified in Table 1 
in § 2755. The Proposed Amendments add text that specifies the requirements will 
apply only through MY 2023  for consistency with Proposed Amendments to other 
sections. This text provides consistency with proposed revisions to § 2753(c), and the 
proposed new subsection 2753(d), that require all engines in MY 2024 and subsequent 
model years to  obtain c ertification of a complete evaporative emission control system, 
and to  use the same test and certification procedures, regardless of their displacement 
category. Under the Proposed Amendments, the separate certification procedure for engines less than 80 cc —and associated permeation emission standards—will not 
apply after MY  2023.  
Rationale . As described in the purpose and rationale for § 2754(a)  in this section B of 
this chapter, the Proposed Amendments set the evaporative emission standards for all SORE except generator engines to zero, and set more stringent emission standards for generator engines, beginning in MY  2024. The proposed changes to this section 
(§ 2755) are necessary to implement the new emission standards and test procedures 
for MY 2024 and subsequent model years, while at the same time continuing to allow 
flexibility for earlier model years, and are necessary to provide consistency with the 
Proposed Amendments to § 2753(c). Under the Proposed Amendments to § 2753(c) 
and (d), beginning with MY  2024, all SORE equipment must use evaporative emission 
testing using TP -902 for certification, including engines with displacement less than  
244 80 cc. This change obviates the need for the permeation emission standards for any 
SORE in MY  2024 and subsequent model years.  
§ 2756. Fuel Cap Performance Standard  
Purpose. The current regulations establish three  fuel cap performance  standards  for 
SORE  with engine displacement  greater than 80 cc. The Proposed  Amendments make  
three  changes  to this section:  
• The first deletes the text, “or equipment that use small off -road engines w ith 
displacements > 80 cc ”, to expand the applicability of the fuel cap standards to 
SORE with small displacement volumes.  
• The second adds new text, “ Fuel cap tether must meet the durability 
requirements in TP -902.” This text establishes a fourth performance standard.  
• The third adds a fourth row to the standards table in § 2756 that establishes the 
applicability of the existing three performance standards to all SORE, and the 
proposed fourth standard, to begin in MY  2024.  
Rationale. The rationales  for the Proposed  Amendments to § 2756 are as follows:  
• The first and third changes are necessary to provide consistency with other Proposed Amendments to the evaporative emission regulations. As described in the purpose and rationale for § 2754(a)  in this section B of this chapter, the 
Proposed Amendments provide text in a new ly proposed  subsection 2753(d) 
that requires all engines in MY 2024 and subsequent model years to obtain certification of a complete evaporative emission control system, and to use the 
same test and certification procedures, regardless of their displacement category. Under the Proposed Amendments, the separate certification procedure for engines less than 80 cc will not apply  after MY 2023.   
• The second change is necessary to remedy a problem found with some types of fuel caps and tethers. As described in section D in Chapter  II of this Staff 
Report, some fuel caps incorporate fuel gauges that extend into the fuel in the fuel tank or otherwise come into contact with liquid fuel inside the fuel tank. 
These tethers and fuel caps can cause fuel to spill or drip when removing a cap 
from the fuel tank. During evaporative emissions compliance testing and other observations of engines, CARB staff have observed fuel spilling or dripping from several pieces  of equipment when the fuel cap was removed. The current 
test procedures do not assess this spillage, which could result in excess 
emissions. This spillage should be assessed to ensure that engines determined to be in compliance with emission standards do not result in excess emissions. 
Consequently, the Proposed Amendments add a new “Fuel Cap and Tether Spill Test ” as § 2.1(f)  in TP -902 (see  the purpose and rationale for § 2.1(f)  in 
section D of  this chapter), and add a new performance standard in § 2756 t hat 
references that test.   
245 § 2757. Optional Evaporative Emission Standards  
Purpose. The current regulations in this section establish optional permeation and 
diurnal emission standards for advanced fuel system designs that reduce or eliminate 
carburetor and  permeation emissions . These optional evaporative emission standards 
are emission targets that are more stringent than the evaporative emission standards set out in §§ 2754 and 2755.  These emission standards are often referred to as the 
“Blue Sky Standards” because a manufacturer certifying to an optional evaporative 
emission standard would be allowed to affix a “Blue Sky Label” on their equipment. The Blue Sky Standards were developed to allow manufacturers to receive recognition for certifying to lower emission standards, but CARB has no record of any 
manufacturer taking advantage of the program for spark -ignition engines.  These 
standards are referenced by § 2753(c) as one of two options for certification of an 
evaporative emission control system in SORE with displacement less than or equal to 80 cc.  
The Proposed Amendments add text that specifies the Blue Sky Standards will apply 
only through MY 2023  for consistency with Proposed Amendments to other sections. 
This text provides consistency with proposed revisions to § 2753(c), and the newly 
proposed subsection 2753(d), that require all engines in MY 2024 and subsequent 
model years to  obtain c ertification of a complete evaporative emission control system, 
and to use the same test and certification procedures, regardless of their displacement category. Under the Proposed Amendments, the separate certification procedure for engines less than 80 cc —and referenced Blue Sky Standards —will not apply after MY 
2023.  
Rationale . As described in the purpose and rationale section for § 2754(a)  in this 
section  B of this chapter, beginning with MY  2024, the Proposed Amendments set the 
evaporative emission standards for all SORE except generator engines to zero, and set 
more stringent emission standards for generator engines. The Proposed Amendments 
set the evaporative emission standards for generator engines to zero for MY  2028 and 
subsequent model years. The proposed changes to this section (§  2757) are necessary 
to implement the proposed new emission standards and test procedures for MY  2024 
and subsequent model years, while at the same time continuing to allow flexibility for earlier model years, and are necessary to provide consistency with the Proposed Amendments t o § 2753(c). Under the Proposed Amendments to § 2753(c) and (d), 
beginning with MY  2024, all SORE equipment must use evaporative emission testing 
using TP -902 for certification, including engines with displacement less than 80 cc. In 
addition, the Blue Sky  Standards do not include hot soak emissions and will no longer 
be lower than the evaporative emission standards in § 2754 once the emission 
standards of zero become effective. These changes obviate the need to certify any 
SORE to the permeation emission standards or Blue Sky Standards beginning in MY 2024.   
246 § 2758. Test Procedures  
§ 2758(a)  
Purpose. The current regulations in § 2758(a)  specify  which  version  of TP-902 
manufacturers  must  follow to determine  compliance  with § 2754. The required  TP-902 
version  vary by SORE  model  year and by which  CP-902 version  is followed.  There are 
three  Proposed  Amendments  to this section:  
• The first changes text in § 2758(a)(3) to limit the applicability of the TP-902 
version  amended May 6, 2019 , to MYs  2020 and 2021;  
• The second adds a new subsection 2758(a)(4) that allows manufacturers for 
MYs 2022 and 2023 to have the option to use the current versions of CP -902 
(last amended September  18, 2017), and TP -902 (last amended May 6, 2019), or 
the proposed versions of CP -902 and T P-902 included in the Proposed 
Amendments; and  
• The third adds a new subsection 2758(a)(5) that requires manufacturers for 
MY 2024 and subsequent model years to follow the proposed version of TP -902 
included in the Proposed Amendments . 
Rationale . The propos ed changes to this section § 2758(a) are necessary to implement 
the proposed changes to TP -902. (Section D in this chapter describes the Proposed 
Amendments for TP -902.) The addition of text to allow applicants the option to follow 
either the current or proposed versions is necessary to allow flexibility and prevent 
unnecessary confusion and costs for manufacturers that could result from changing the reference document editions for MYs 2022 and 2023 with design and testing already underway.  
§§ 2758(b) and ( c) 
Purpose. The current regulations in §§ 2758(b) and (c) specify which test procedures 
manufacturers must follow to determine  compliance with §§  2755 and 2757, 
respectively. The requirements vary by model year. Subsections 2758(b)(3) and (c)(3) 
specify the test procedures for MY  2020 and subsequent model years without an end 
date. The Proposed Amendments add text that specifies the test procedure requirements will apply only through MY 2021 and add new subsections 2758(b)(4) and (c)(4) that provide test procedure requirements for MYs 2022 and 2023 for 
consistency with Proposed Amendments to other sections. The newly proposed 
subsections 2758(b)(4) and (c)(4) retain the existing test procedure options and add 
the proposed version of TP -901 included in the Proposed Amendments as an optional 
test procedure for determining fuel line permeation emissions. This text provides 
consistency with proposed revisions to §  2753(c), and the newly proposed § 2753(d), 
that require all engines in MY 2024 and subsequent model years to  obtain c ertification 
of a complete evaporative emission control system, and to use the same test and certification procedures, regardless of their displacement category. Under the Proposed Amendments, the separate certification procedure for engines with  
247 displacement less than or equal to 80 cc —and associated standards specified in 
§ 2755 and §  2757 and test procedures specified in §§ 2758(b) and (c) —will not apply 
after MY 2023.  
Rationale . As described in the purpose and rationale for § 2754(a)  in this section B of 
this chapter, the Proposed Amendments set the evaporative emission standards for all 
SORE except generator engines to zero, and set more stringent emission standards 
for generator engines, beginning in MY  2024. The Proposed Amendments set the 
evaporative emission standards for generator engines to zero beginning in MY  2024. 
The proposed changes to these sections (§§ 2758(b) and (c) ) are necessary to 
implement the newly proposed emission standards and test procedures for MY  2024 
and subsequent model years, and are necessary to provide consistency with the 
Proposed Amendments to § 2753. For MYs 2022 and 2023, manufacturers may choose 
to use the proposed version of TP -901 included in the Proposed Amendments to 
better ensure their fuel tanks meet the permeation emission standards. Under the 
Proposed Amendments to § 2753(c) and  (d), beginning with MY  2024, all SORE 
equipment must use evaporative emission testing using TP -902 for certification, 
including engines with displacement less than or equal to 80 cc. This change obviates 
the need for the standards specified in § 2755 and § 2757 and associated test 
procedure requirements specified in §§ 2758(b) and (c)  for any SORE in MY  2024 and 
subsequent model years.  
§ 2759. Equipment and Component La beling 
§ 2759(c)(4)  
Purpose. The current regulations in § 2759 specify  equipment  and component  labeling 
requirements  to identify  equipment  that meets  applicable  evaporative  emission 
standards . Section  2759(c)(4)  specifies  the information  a certification  label must  
contain  and its formatting.  There are four Proposed  Amendments to this section:  
• The first changes the capitalization of the text “IMPORTANT EMISSIONS 
INFORMATION” to “Important Emissions Information” in § 2759(c)(4)(A) t o aid 
in making the text accessible  to everyone, including people with visual 
impairments and assistive technology users. 
• The second deletes the text “revised October 2008” that follows SAE  J1930 in 
§ 2759(c)(4)(C) to provide consistency with the proposed definition included as 
§ 2752( a)(31), which incorporates by reference the most recent version available 
(March 2017).  
• The third changes the capitalization of the text “THIS ENGINE MEETS 2006 CALIFORNIA EVP EMISSION REGULATIONS FOR SMALL OFF -ROAD 
ENGINES” to “This e ngine meets 2006 C alifornia ev p emission r egulations for 
small o ff-road engines” in § 2759(c)(4)( E) to aid in making the text accessible to 
everyone, including people with visual impairments and assistive technology users.    
248 • The fourth updates the text in § 2759(c)(4)(F), which lists the different versions 
of Attachment 1 of CP -902 that contain the classification criteria for 
determining an evaporative family, to include a reference to the Attachment 1 
version that is amended by the Proposed Amendments.  
Rationale. The rationales  for the Proposed  Amendments to § 2759 are as follows:  
• The first and third changes are necessary to make label text easier to read and 
consistent with current accessibility guidelines. 
• The second change is necessary to provide consistency with the proposed 
definition included as § 2752( a)(31) and prevent confusion and regulatory 
uncertainty for manufacturers that create the labels.  
• The fourth change is necessary to provide consistency with other Proposed 
Amendments to the evaporative emission regulations. Section E of this chapter 
summarizes the Proposed Amendments to Attachment  1 of CP -902 and 
Appendix E provides Attachment 1 in its entirety with underline/strikeout text 
to illustrate the specific Proposed Amendments.  
§ 2761. Emission- Related Defect and Production Volume Reporting 
Requirements  
§ 2761(f)(6)  
Purpose. The current regulations in § 2761 specify requirements to report emission-
related defects affecting a given evaporative family of 2007 model year and later 
SORE. Section 2761(f) specif ies the requirements for end -of-year and final production 
volume reports, and subsection 2761(f)(6) allows a  report submitted to CARB to meet 
the requirements of section 1054.250 of the “California Exhaust Emission Standards 
and Test Procedures for New 201 3 and Later Small Off -Road Engines; Engine- Testing 
Procedures (Part 1054),” [“Part 1054”] adopted October 25, 2012, for an engine family to be used to meet the requirements of this section for an evaporative family that is 
equivalent to the engine family.  The Proposed Amendments add text to update the 
reference to the Part 1054 version that is amended by the Proposed Amendments.  
Rationale . This change is necessary to provide consistency with other Proposed 
Amendments to the SORE regulations. Section F of this chapter summarizes the Proposed Amendments to Part  1054 and Appendix F provides Part  1054 in its entirety 
with underline/strikeout text to identify the specific Proposed Amendments.  
§ 2764. Evaporative Emission Control System Warranty Statement  
§ 2764(b ) 
Purpose. The current regulations in § 2764 specify requirements for manufacturers to 
provide a California Evaporative Emission Control System Warranty, a copy of which must be included with a ny application for an evaporative emission control system  
249 certification . The Proposed Amendments add new text to the required first paragraph 
of the “Owner’s Warranty Responsibilities” portion of the statement, as indicated by 
underline formatting in the following:  
“As the (equipment  type)  owner,  you are responsible f or performance  of the 
required  maintenance  listed in your owner’s manual.  (Holder’s  name)  
recommends  that you retain  all receipts  covering  maintenance on your 
(equipment  type),  but (Holder’s  name)  cannot  deny  warranty coverage  solely for 
the lack of receip ts or for your failure to ensure  the performance  of all 
scheduled  maintenance.” 
Rationale . This change is necessary to ensure  ultimate purchasers know their warranty 
claims cannot be denied solely for failure to ensure the performance of all scheduled 
main tenance.  If manufacturers improperly deny warranty claims, equipment owners 
may forego repairs at their own expense that should have been repaired at no cost 
under warranty, and instead continue to use defective equipment that exhibit excess 
emissions . This change corrects an oversight at the time the evaporative emission 
regulations were adopted and provides consistency with comparable provisions in the 
SORE exhaust emissions regulations in Title 13, CCR,  § 2406(a) . 
§ 2765. New Equipment Compliance Testing  
§ 2765(a)(7)  
Purpose. The current regulations in § 2765 establish the requirements for new 
equipment compliance testing. As described in § 2765(a)(1), the regulations specify 
that the Executive Officer may order a manufacturer to make available for compliance 
testing and/or inspection five or more fuel lines, carbon canisters, or fuel tanks, or one or more engines or equipment units with complete evaporative emission control systems. Section  2765(a)(1) further specifies that the equipment to be tested “… must 
be selected at random from sources specified by the Executive Officer according to a 
method approved by the Executive Officer…”  Sections 2765(a)(2) through (10) list 
specific additional selection and testing requirements. Section  2765(a)(7) states 
“Engines or equipment must be randomly chosen from the selected evaporative family 
or subgroup.” The Proposed Amendments adds the text “, as designated by the 
Executive Officer” to the end of this sentence to provide clarity and consistency with the requirement in § 2765(a)(1).  
Rationale . This change is necessary to provide clarity and improve regulatory certainty 
by fixing an oversight in § 2765(a)(7) that occurred at the time the regulations were 
adopted. The current text of § 2765(a)(7) does not specify the method for making the 
random selection of equipment for testing. As evidenced by the adopted text in § 2765(a)(1), the intent of the regulations is for the Executive Officer  to be the entity 
responsible for specifying sources of equipment to be tested and methods for the random selection of the equipment. The Proposed Amendments to § 2765(a)(7) are 
consistent with that intent.   
250 § 2766. Exemptions 
§ 2766(b)  
Purpose. The current regulations in § 2766(b) describe the small production volume 
tank exemption for engines or equipment that qualify under §  2752(a)(30) . The current 
regulations in § 2752(a)(30) provide a definition of “small production volume tank” for 
application of the exemption. The Proposed Amendments change the defini tion’s 
reference from §  2752(a)(30)  to § 2752(a)(3 4) to accommodate the Proposed 
Amendments’ addition of new definitions in § 2752(a).  
Rationale . This change is necessary to help ensure manufacturers reference th e correct 
regulation subsection.  
§ 2768. Va riances 
Purpose. The current regulations in § 2768 establish the requirements that must be 
met for a SORE manufacturer to obtain  a variance if the manufacturer cannot meet the 
requirements set forth in §§  2754 through 2757  due to extraordinary reasons beyo nd 
the manufacturer’s reasonable control.  The Proposed Amendments repeal this entire 
section on variances for consistency with other Proposed Amendments to the 
evaporative emission regulations.  
Rationale . This change is necessary to achieve the broader goal of this rulemaking: 
accelerate the manufacture and sale of ZEE in place of SORE equipment to achieve the SORE emission reductions expected under the 2016 State SIP Strategy and  EO N -
79-20. When the variance provision is invoked, excess evaporative emissions can 
occur. As conditions of variances that have been granted, manufacturers have used 
banked evaporative emissions credits or set a higher EMEL to offset those excess 
emissions. Once the proposed emission standards of zero are effective for SORE —
MY 2024 for all SORE except generator engines, and MY  2028 for generator 
engines—having sufficient credits to offset excess emissions will become increasingly more difficult. Allowing excess emissions to occur without adequate offset would 
conflict with, and increase the burden of, already challenging efforts to comply with the 2016 State SIP Strategy and EO E -79-20. Furthermore, ZEE are now available for 
all small off -road equipment categories , and the number and breadth of models is 
expected to continue increasing as it has in recent years.  In addition, while the current 
availability of zero -emission generators is limited, the Proposed Amendments allow 
more time for generators to meet emission standards of zero to provide more time for innovation and growth in the zero -emission generator market. The improvement in 
ZEE availability since the time §  2768 was established, and the schedule for 
implementation of the proposed emission standards of zero, obviate the need for the variance provisions in the evaporative emission regulations.  
Repealing the variance provision  would ensure equity for all manufacturers, because all 
manufacturers would be required to comply with emission standards as set forth in the  
251 regulations. The addition of evaporative emission credit trad ing in the proposed 
§ 2754.1(e)  would also alleviate the need for variances, which would enable all 
manufacturers to certify their engines in a manner consistent with the SORE 
evaporative emission standards; manufacturers who could not meet the emission standards could acquire credits to offset emissions above the emission standards.  As 
discussed in the SRIA in Appendix I, repealing the variance section is not expected to 
have an economic impact. 
C. TP-901, Test Procedure for Determining Permeation Emissions from Small 
Off-Road Engine Fuel Tanks 
This section provides a summary, purpose, and rationale for each Proposed 
Amendment to “Small Off -Road Engine Evaporative Emissions Test Procedure, 
TP-901, Test Procedure for Determining Permeation Emissions from Small Off -Road 
Engine Fuel Tanks” (TP -901). The SORE evaporative emission regulations require the 
use of TP -901 to determine the permeation rate from fuel tanks of spark -ignition small 
off-road engines and equipment.  This test procedure is incorporated by reference in 
Title 13, CCR, § § 2755 a nd 2758. Appendix C of this Staff Report provides the full 
language of this test procedure with Proposed Amendments shown in strikeout and 
underline formatting.  
Global Amendments throughout TP-901 
The following proposed global changes provide updated and c larifying text that does 
not alter current requirements for SORE equipment.  
Acronym Change  
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before  “Air Resources Board ,” for consistency with recent CARB 
document style practices designed to improve clarity. 
Rationale . This change reflects the California Air Resources Board’s recent change to, 
and preferred use of, the acronym “CARB” versus the prior acronym, “ARB,” and the 
entire agency title, “California Air Resour ces Board.”  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents accessible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines.   
252 Table of Contents Change  
Purpose. The Proposed Amendments change the formatting of section titles and text 
in all capital letters to mixed case to aid in making documents accessible to everyone, 
including people with visual impairments and assistive technology users. In addition, 
the Proposed Amendments adjust page numbers to accommodate added or removed text throughout TP-901. Amendments to the Table of Contents reflect these changes.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines. Amending the page numbers is necessary for accuracy and to prevent confusion for the reader.  
Definition of Terms  
Purpose. The Proposed Amendments change “ authorized representative or 
designate” to “ authorized representative or designee” to correct a spell ing mistake in 
the definition of the term “Executive Officer.”  
Rationale . California Administrative Law (Title  1, CCR, § 16(a)(4)) requires that 
California regulations be free of spelling errors. The change to correct the spelling of designee is necessary to provide clarity for readers and does not affect any 
requirements for SORE certification and testing.  
§ 2. Principle and Summary of Test Procedure  
Purpose. The current regulations specify: “ Prior to permeation testing of the fuel 
tanks, durability testing and preconditioning are performed. Durability testing exposes 
the fuel tanks to pressure and vacuum extremes, ultraviolet radiation, fuel sloshing, 
and fuel cap installation cycles. After du rability testing, the fuel tanks are filled with 
fuel and allowed to precondition to maximize the permeation emissions. ” The 
Proposed Amendments add the text “ to nominal capacity” after the current text “ are 
filled with fuel,“ to specify fuel tanks must be  filled to nominal capacity after durability 
testing,  which adds clarity and ensures fuel tanks remain at true nominal capacity for 
the duration of preconditioning.  The definition of “nominal capacity” is specified in 
the SORE evaporative emission regulati ons. Per Title 13, CCR, §  2752, “nominal 
capacity” means the volume of fuel indicated by the manufacturer that represents the 
maximum recommended fill level.  
Rationale . This change is necessary for clarification because f uel tank material may 
expand during  durability testing or fuel may evaporate. A dditional fuel must be added 
so that fuel tanks remain at nominal capacity. Filling the  fuel tank to  nominal capacity 
before  preconditioning ensures the maximum nominal surface area is saturated and 
therefore produces more accurate permeation test emission rates.   
253 § 5. Equipment  
Purpose. There are four Proposed  Amendments to this section:  
• The first r emov es the entirety of  § 5(a), which currently describes materials that 
may be used to seal the fuel tank : “A handhe ld, thermostatically controlled, 
Teflon coated aluminum hot plate (handheld fusion welder) and coupons of the 
same material as the tank. Both the handheld fusion welder and coupons must be of sufficient diameter to completely cover the opening(s) of the ta nk 
(optional) .”  
• The second re- letters s ubsections (b) through (g) to  (a) through (f) , respectively,  
to accommodate the proposed removal of subsection (a)  and maintain 
sequential subsection lettering .  
• The third removes “optional” from the end of §  5(f) [re-lettered  to 5(e)], which 
describes  the relative h umidity measuring instrument .  
• The fourth removes the specified  adoption and amendment dates in the 
reference to TP -902 in § 5(g) [ re-lettered  to 5(f)], as indicated by strikeout in this 
sentence: “ Instru mentation meeting the requirements of section 4 of TP -902, 
adopted July 26, 2004, and last amended May 6, 2019 , (if permeation testing 
will be performed according to section 12 of this test procedure). ”  
Rationale. The rationales  for the Proposed  Amendment s to § 5 are as follows:  
• Removal of  materials that may be used to seal the fuel tank  from the equipment 
list is necessary to provide consistency with the Proposed Amendment to § 10(a) to require  the production volume fuel cap to be used , rather than allow 
the option to seal a tank by fusion welding a coupon over the fuel fill neck 
opening to make a seal . 
• The change in subsection lettering is necessary to provide consistent lettering 
and to prevent confusion for the reader.  
• Removal of the word “optional” for the relative humidity measuring instrument is necessary to provide consistency with the Proposed Amendment to §§ 11(a)(2) and (8) that would require relative humidity to be measured and 
recorded .  
• Remov al of the specific adoption and amendment dates in the reference to 
TP-902 is necessary to ensure instrumentation meets requirements set forth in 
the most current TP -902 test procedure available . 
§ 6. Certification Test Fuel  
Purpose. The current regulations in § 6 provide:  
“The fuel specified  in part II, section  A.100.3.1.1  of the California  2015 and 
Subsequent  Model  Criteria  Pollutant Exhaust  Emission Standards  and Test 
Procedures  and 2017  and Subsequent  Model  Greenhouse Gas Exhaust   
254 Emission Standards  and Test Procedures  for Passenger  Cars,  Light Duty Trucks,  
and Medium -Duty Vehicles,  as last amended  September  2, 2015,  may be used  
as an alternative  test fuel to certify fuel tanks  for use on engines  and equipment  
through  model  year 2019.”  
The Proposed Amendments remove this entire paragraph to provide consistency with 
current regulatory requirements.  
Rationale . This change is necessary to prevent confusion because t he alternative test 
fuel specified above was allowed only through MY 2019, so is no longer applicable.  
§ 7. Calibration Procedure  
Purpose. The current regulations in § 7 specify:  “All instruments and equipment used 
in this procedure shall be calibrated at the interval specified by the manufacturer.  The 
balance listed in section 5(b) shall be calibrated annually per the balance 
manufacturer’s instructions using National Institute of Standards and Technology 
(NIST)- traceable mass standards. The NIST -traceable mass standards shall be 
calibrated annually by an independent organization.” The Proposed Amendments 
change “interval” to “time interval” and add language specifying that instruments and 
equipment shall be calibrated more often as needed per manufacturer instructions, for 
example, when equipment is moved or repaired. The Proposed Amendments also 
change the re ferenc e to § 5(b), from (b) to  (a), in order to refer to the correct 
subsection, given the proposed removal of the current § 5(a) and re -lettering of §  5(b) 
and subsequent subsections. In addition, the Proposed Amendments change the 
requirement to use NIST -traceable mass standards  to instead allow the use of Système 
International  d'Unitésii (SI) traceable mass standards through NIST or another member 
of the Mutual Recognition Arrangement  of the Comité International des Poids et 
Mesuresjj (CIPM  MRA ). 
Ratio nale. The change to specify “time interval” is necessary to avoid confusion for a 
tester. The changes to specify that instruments and equipment shall be calibrated more often as needed per manufacturer instructions are necessary to provide certainty for te sters who need to calibrate instruments or equipment more often and to ensure 
that instruments and equipment are properly calibrated and produce valid data. The change to the reference lettering from (b) to (a) is necessary to provide  consistent 
numbering  and to prevent confusion for the reader. Requiring  SI-traceable standards 
is consistent with current industry practice and is necessary to allow flexibility for 
manufacturers ar ound the world to use other recognized international standards  while 
still main taining the consistency necessary to ensure test data accuracy, precision, and 
comparability to the emission standards, as well as a level playing field amongst 
                                            
ii International System of Units  
jj International Committee for Weights and Measures   
255 manufacturers. Accurate and precise data are necessary to ensure that fuel tanks  
determined to be in compliance with emission standards assessed using TP -901 are 
indeed compliant and do not result in excess emissions.  
§ 8. Durability Demonstration  
§ 8.1 Pressure Test  
Purpose. The Proposed  Amendments to this section  include the following  changes:  
• The first corrects a typographic error by replacing the text “The Pressure test” 
with “A pressure test” in the first sentence of the first paragraph.  
• The second divides the first paragraph into three paragraphs, with the second 
and third paragraphs inset and labeled as subsections (a) and (b) to better delineate the different steps of the pressure test.  
• The third m odifies text to specify the pressure test shall be performed on fuel 
tanks without fuel and prior to any other durability testing or preconditioning . 
The current regulations specify that the pressure test shall be performed prior to any preconditioning of the fuel tank.  
• The fourth provides additional instructions to meet an existing requirement to determine a fuel tank system’s pressure and vacuum limits. The current regulations require a manufacturer to: “Determine the fuel tank system’s design 
pressure and vacuum limits under normal operating and storage conditions 
considering the influence of any associated pressure/vacuum relief components. ” How ever, the current regulations do not specify how to make 
this determination. The Proposed Amendments add the following text to describe the procedural steps and equipment to be used, including steps to 
measure and record  the maximum and minimum pressure li mits of the test fuel 
tank, which is necessary to determine  the pressure and vacuum limits  required 
for the next Proposed Amendment.  
“To do this, measure the pressure limits using a fuel tank from an 
evaporative emission control system that is not used for  any other 
portion of this test procedure by installing a pressure transducer in the 
fuel tank. With the exception of the use of the pressure transducer and connection to a carbon canister, as applicable, the fuel tank and fuel tank configuration used for these pressure measurements shall be identical to those used in the remainder of this test procedure. Using compressed air 
of no less than 21 °C, pressurize the fuel tank with compressed air, seal 
the fuel tank, and measure the pressure every second for 5 minutes. Use a vacuum pump to draw a vacuum in the fuel tank, seal the fuel tank, and measure the pressure every second for 5 minutes. Record the maximum and minimum pressure measurements on the test report. ” 
• The fifth adds a new provision to the newly labeled subsection (a): “Subsection  (b) of this test is not required if the fuel tank pressure does  not  
256 exceed a gauge pressure  of + 1.0 kPa for at least one minute when pressurized 
and the fuel tank vacuum does not exceed a gauge pressure of – 1.0 kPa for at  
least one minute when a vacuum is drawn in the fuel tank .” 
• The sixth removes this current provision from the newly labeled subsection (b): 
“If the fuel tanks have no features that would cause positive or negative 
pressure to accumulate during normal opera tion or storage, then a pressure 
test is not required. ” 
• The seventh removes this current provision at the end of § 8.1: “Tanks that have 
a secondary operation for drilling holes for insertion of fuel line and grommet 
system may have these eliminated for pu rposes of durability and permeation 
testing. ” 
Rationale. The rationales  for the Proposed  Amendments to § 8.1 are as follows:  
• The first and second Proposed Amendments are necessary to improve clarity and prevent confusion for testers, better ensuring correc t completion of the 
procedural steps.  
• The third change, to require p erform ance of  a pressure test without fuel  and 
prior to any other portion of the durability demonstration or preconditioning of the fuel tank , is necessary to further clarify the existing requirement to perform 
a pressure test prior to any preconditioning of the fuel tank. Preconditioning 
starts to occur when fuel is introduced into the fuel tank, so the existing requirement would preclude performance of a pressure test if fuel were in the fuel tank. However, some manufacturers have submitted test reports that 
indicated a pressure test was performed during preconditioning, which 
indicates that those pressure tests were conducted inconsistent with the necessary procedures that ensure accurate  pressure test readings. Thus, this 
change is also necessary because the presence of fuel in the fuel tank could  
interfere with the pressure test. Performing a pressure test with fuel in the fuel 
tank would also result in the repeated introduction of air i nto the fuel tank and 
removal of fuel vapors from the fuel tank. Over the course of the 10,000 cycles required for the test, a significant amount of fuel vapors could be removed from the fuel tank, degrading the fuel and resulting in test results that woul d not 
represent real -world permeation emissions from fuel tanks.  
• The fourth change, to provide additional instructions, is necessary to provide the clarity and consistency necessary to ensure different testers use a consistent approach known to provide accurate test results, which is necessary to ensure 
that fuel tanks determined to be in compliance with emission standards 
assessed using TP -901 are indeed compliant and do not result in excess 
emissions. In addition, adding explicit instructions to measure a nd record the 
pressure limits is necessary to provide the information needed to determine 
whether the pressure test may be omitted, per the Proposed Amendment described next .   
257 • The fifth change is necessary because it improves the reliability of the 
determi nation that a pressure test may be omitted by providing explicit, 
measurable criteria for determining whether a pressure test may be omitted, 
rather than relying on a subjective assessment, which in turn improves safety and the certainty of later test results. If a pressure test is omitted inappropriately (e.g., the visual assessment of the physical fuel tank and its 
design schematics does not detect that a fuel tank indeed has features that 
would cause positive or negative pressure to accumulate), then two  negative 
consequences could occur. First, excess pressurization or vacuum could result in unsafe conditions for testers, and second, permeation test results may not be 
valid. Fuel tanks that pressurize to a greater extent in real -world use than in 
certifi cation tests could have higher permeation or venting emissions. The result 
could be higher emissions from SORE than are expected based on certification test results.  The Proposed Amendments would allow testers to omit the 
pressure test if the fuel tank pre ssure measurements are not higher or lower 
than the gauge pressure range of + 1.0 to – 1.0 kPa for more than one minute. 
This pressure range is based on discussions with manufacturers, who have indicated that fuel tanks that are connected to carbon caniste rs often 
experience minimal pressure changes. The pressure range of + 1.0 to – 1.0 kPa  
would ensure that small fluctuations that naturally occur when measuring pressure are not interpreted to be accumulation of pressure or vacuum. Using 
these criteria woul d enable testers to determine based on pressure 
measurements whether a fuel tank  has any features that would cause positive or 
negative pressure to accumulate during normal storage and operation, rather 
than rely on a subjective visual assessment .  
• The sixth change, to remove the provision “If the fuel tanks have no features that would cause positive or negative pressure to accumulate during normal operation or storage, then a pressure test is not required,” is necessary to avoid unnecessary and redundant effort, and prevent confusion. The fifth change 
described above provides an improved method for determining whether fuel 
tanks have features that would cause positive or negative pressure to accumulate during normal operation or storage . 
• The seventh change,  to remove  the provision  that allows the  elimination of  
holes in the tank before testing,  is necessary to provide  a tank configura tion 
closer to production tanks (i.e., one that better simulates  real-world operating 
and storage conditions),  and therefore p rovide more accurate permeation test 
emission rates, which is necessary to ensure certified equipment does not produce excess emissions. 
§ 8.3. Ultraviolet Radiation Exposure 
Purpose. The current regulations specify: “ A sunlight exposure test shall be perf ormed 
by exposing each fuel tank to an ultraviolet light of at least 24 W·m-2 
(0.40  W·hr·m-2·min-1) on the tank surface for at least 450 hours. Alternatively, each fuel 
tank may be exposed to direct natural sunlight for at least 450 daylight hours.” The  
258 Proposed Amendments add language that specifies a tester must  measure and record 
ultraviolet (UV)  light intensity at least every hour.  
Rationale . This change is necessary because temperature changes in the test area  
throughout the day may cause the UV lig ht intensity to vary. Measuring and recording 
hourly UV intensity values provides documentation of compliance with the existing 
testing requirement for at least 450 hours of UV light exposure above the required 
intensity. In addition, such hourly tracking will better enable testers to make timely 
adjustments as needed to ensure  UV light intensity remains at the appropriate 
intensity throughout each day. This change requires testers to verify they are complying with the existing requirement for UV light intensity. Exposure to sunlight or 
other sources of UV light can degrade materials in the evaporative emission control 
system, reducing their ability to resist permeation. If the intensity of the UV light does not meet the minimum requirement, the effect of the exposure on permeation emissions would be reduced and certification test results would not represent real -
world emissions.  
§ 8.4. Fuel Cap Installation Cycles 
Purpose. The current regulations specify: “ The following test is optional: Installation 
cycles shall be performed with fuel caps intended for use with the fuel tanks by putting 
each fuel cap on and taking it off 300 times. Tighten the fuel cap each time in a way 
that represents typical usage. ” The Proposed Amendments remove the text, “The 
following test is optional,”  to require the fuel cap installation cycles.  
Rationale . This change is necessary for two reasons.  First, it would ensure all testers 
perform the same steps during TP -901 to confirm durability of the fuel cap and its 
ability to maintain a seal under normal operating and storage conditions. For example, 
if only those manufacturers whose fuel caps were designed to be sufficiently durable to maintain an adequate seal for at least 300 installation cycles performed the test in this § 8.4 , the results would not be equitable for the manufacturers performing the 
fuel cap installation cycles. Second, if the fuel cap installation cycles were not performed, poorly- designed  fuel caps may not maintain an adequate seal, which could 
result in excess emissions and confound efforts to achieve emission reductions 
expected under the 2016 State SIP Strategy.  Installing and r emoving  the fuel tank cap 
simulate s typical usage and ensures the tank remains sealed throughout storage and 
normal operation. Ensuring fuel caps are capable of maintaining a seal throughout 
storage and normal operation ensures there are no excess evaporative emissions leaking from the fuel cap.  
§ 8.5. Fuel Cap and Tether Spill Test  
Purpose. The Proposed Amendments add a new subsection 8.5 to set requirements 
for a new fuel cap and tether spill test  with specific instructions for filling the fuel tank, 
installing and loosening the cap, fully extending the tether within a specified  
259 timeframe, and reporting any dripping, spraying or leaking of fuel from any part of the 
fuel cap or tether.  
Rationale . This change is necessary to ensure tether  and fuel cap designs do not cause 
excess evaporative emissions. The evaporative emission regulations in Title 13, 
CCR,  § 2756 require fuel caps for fuel tanks used on engines with displacement 
greater than 80 cc to be secured to the fuel tank, equipment or engine with a tether.  
This prevents fuel caps from falling and becoming damaged or dirty. It also prevents them from being lost, which could lead to excess emissions from the fuel tank if the 
cap is not replaced. S ome fuel  caps are equipped with internal tethers, i.e., with 
tethers that are attached to a location inside the fuel tanks. Other fuel caps 
incorporate fuel gauges that extend into the fuel in the fuel tank or otherwise come into contact with liquid fuel i nside the fuel tank. During evaporative emissions 
compliance testing and other observations of engines, CARB staff have observed fuel spilling or dripping from several pieces of equipment when the fuel cap was removed. Based on these observations, CARB staff concludes that there is greater likelihood that these tethers and fuel caps may cause users of SORE equipment to spill or drip 
fuel when removing a cap from the fuel tank, thereby creating excess emissions 
neither captured in current test procedures nor  reflected in CARB’s emissions 
inventory. Emissions from spillage are difficult to quantify and are not measured in the test procedures because no spillage is permitted by the regulations. Spilled fuel often 
evaporates quickly, but it can also pollute soil  or water, where it may not evaporate 
entirely. Once spilled fuel has evaporated, it can negatively impact air quality. 
Therefore, it is necessary to amend the test procedures to ensure that fuel caps and tethers are designed to prevent fuel spillage. It i s also necessary for certification 
applicants to include information in their applications to show that their engines meet relevant standards.  
This test simulates an equipment user removing the fuel cap to check the fill level or add fuel. Some users might  drop the fuel cap after removing it, allowing it to hang 
from the tether. Others may hold the fuel cap after removing it. However, the 
proposed instructions for this test will ensure a uniform procedure for the varying 
designs of fuel caps and tethers used on SORE fuel tanks.  
§ 9. Preconditioning Procedure  
Purpose. The current regulations in this section specify the steps for preconditioning 
the five fuel tanks that are subject to permeation testing. The current regulations 
include these procedural requirements:  
“After  performing  the durability tests,  fill each  tank to its nominal  capacity with 
the fuel specified  in section  6 of this procedure  and install a production  fuel cap 
expected  to have  permeation  emissions at least  as high as the highest  emitting  
fuel cap that will be used  with fuel tanks  from  the evaporative  family. Place  the 
tanks  in a suitable vented  enclosure.  Record  the preconditioning  start date on 
the data sheet.  Soak  the tanks  at a temperature  that never  falls below  38 °C for 
not less than 140 days.  Accelerated  preconditioning  of the tanks  can be  
260 accomplished  by soaking the tanks  at an elevated  temperature.  Data  
documenting  that permeation  emissions from  the fuel tanks  will not increase 
with further preconditioning  must  be provided  for tanks  soaked  less than 
140 days.  The time of the durability demonstration  in section  8 of this 
procedure  may be counted  as part of the preconditioning  procedure  if the 
ambient  temperature  remains within  the specified  temperature  range,  the same  
fuel cap is used  throughout  the durability demonstration  and preconditioning  
period,  and each  fuel tank is at least  50 percent  full; fuel may be added or 
replaced  as needed  to conduct the specified  durability tests.”  
The Proposed  Amendments detailed  in Appendix  C include eight changes  in this 
section:  
• The first requires the tester to measure and record the preconditioning 
temperature at least every five minutes to ensure fuel tanks are soaked at the appropriate temperature  throughout preconditioning.  
• The second requires the tester to take steps during preconditioning to ensure 
fuel remains at nominal capacity to ensure fuel tanks are soaking at their true 
nominal capacity throughout preconditioning.  
• The third requires accelerated preconditioning to be conducted a minimum of  
70 days to ensure tank walls are saturated with fuel . 
• The fourth a dds instructions necessary  to produce  acceptable permeation data 
that would demonstrate  permeation emissions would not increase with further 
preconditioning, which may be collected gravimetrically or using a flame ionization detector (FID).  
• The fifth makes more specific the reference to § 8 for the time of durability demonstration, by providing the specific sections that are relevant, “section  8.2 
through  8.5”, to clarify applicable subsections of durability testing that may be 
counted as preconditioning.  
• The sixth deletes one of the requirements for counting durability testing time as preconditioning, “the same fuel cap is used throughout the durability 
demonstra tion and preconditioning period,” because its inclusion could create 
confusion g iven the production fuel cap must be used throughout testing 
according to TP -901. 
• The seventh adds the following instructions to provide procedural consistency: 
“Record the fuel fill amount and dates on the test repor t if fuel is added or 
replaced.”  
• The eighth adds the following instructions to ensure fuel tank walls are fully 
saturated with fresh fuel : “Drain the fuel tank and refill with fresh fuel to 
nominal capacity 15 days prior to ending preconditioning. The fuel tank must 
not be empty for more than 1 5 minutes. Record the date and time the fuel tank 
is drained  and refilled with fresh fuel , and record the fuel fill amount on the test 
report. ”  
261 Rationale. These changes are necessary  to ensure  permeation  testing  produces  the 
accurate  results necessary  to prevent  an incorrect determination  of compliance  with 
the evaporative  emission standards.  An incorrect compliance  determination  could  lead 
to excess emissions. The specific rationales  for each  of the Proposed  Amendments  to 
§ 9 are as follows:  
• Requiring temperature measurements every five minutes during 
preconditioning is necessary to ensure temperatures do not fall below required 
thresholds, and is consistent with requirements for permeation testing in § 11(a)(7). Temperature influences evaporation and therefore permeation test 
rates, so in order to verify fuel tanks are soaking at the appropriate temperature 
for the duration of preconditioning, temperature must be measured and 
recorded frequently. Per  § 11(a)(7), current regulations require t emperature to 
be measured and recorded every five minutes during permeation testing, which 
indicates  it is feasible and necessary  to measure and record temperature every 
five minutes during preconditioning  as well . 
• Requiring the tester to take steps during preconditioning to ensure fuel remains at nominal capacity is necessary because fuel tank material may expand during preconditioning or fuel may evaporate , so additional fuel may need to be 
added to ensure fuel tanks remain at true nominal  capacity for the duration of 
preconditioning. This could involve testing staff checking the fill level of fuel 
tanks on a periodic basis.  
• Requiring a minimum soak requirement of 70 days for accelerated 
preconditioning is necessary to  better ensure  precond itioning of the fuel tanks 
will not be stopped prematurely (i.e., before the permeation rate stops increasing ). Many manufacturers attempt to accomplish accelerated 
preconditioning of their fuel tanks to finish testing sooner. Often, this involves measuring the mass loss of the fuel tanks every day, beginning the day that preconditioning starts. Their goal is to end preconditioning as soon as possible. 
Requiring a minimum of 70 days of preconditioning will continue to allow 
accelerated preconditioning while decreasing the likelihood that a tester will 
improperly determine the permeation rate has stopped increasing. U.S. EPA requires a minimum preconditioning period of 70 days for SORE fuel tanks, as described in 40 CFR § 1060.520. CARB requires a minimum preconditioning 
period of 70 days for PFCs, as described in TP -502. The proposed minimum 
preconditioning period for SORE fuel tanks would therefore be consistent with the minimum used for testing the same fuel tanks for U.S. EPA and with CARB’s requirements for PFCs, which are often made of similar materials to those used to manufacture SORE fuel tanks.  
• Specific instructions for how to produce  acceptable permeation data that would 
demonstrate  permeation emissions would not increase with further 
preconditioning  is necessary to improve consistency for those implementing  the 
procedure , which better  ensures adequate preconditioning time is 
accomplished, increase s clarity for those reviewing the data, better ensures  
262 accurate evaporative emission compliance determina tions, and better maintain s 
a level playing field among st manufacturers . CARB staff developed the 
instructions based on data that have been provided by manufacturers to 
document  that permeation emissions from the fuel tanks will not increase with 
further p reconditioning . To allow flexibility for manufacturers, the proposed 
instructions provide two options for data that may be provided to document that permeation emissions from the fuel tanks will not increase with further 
preconditioning : one to be used whe n conducting a permeation test by the 
gravimetric method described in § 11 and one to be used when conducting a 
permeation test by the flame ionization detector method in § 12 of TP -901. 
• A more specific reference to § 8 for the time of the durability demonstration is necessary to clarify applicable subsections of durability testing that may be 
counted as preconditioning, which prevents confusion and saves time for 
testers. The time of the pressure test could not be counted as part of the preconditioning pro cedure because the pressure test must be performed 
before any preconditioning and the fuel tanks would not be at least 50 percent full. 
• Removing one of the requirements for counting durability testing time as part of the preconditioning procedure, “ the sam e fuel cap is used throughout the 
durability demonstra tion and preconditioning period,” is necessary to prevent 
confusion given a production fuel cap would be used throughout testing according to TP -901 under the Proposed Amendments. Using the production 
fuel cap throughout the duration of the test procedure ensures real -world 
storage and operation conditions, which enables test emission rates  that better 
reflect real -world emissions and therefore helps prevent the certification of fuel 
tanks that could pro duce excess emissions .  
• Adding a requirement to record the fuel fill amount and dates during 
preconditioning is necessary for reviewers to verify the procedure is followed correctly and consistently by different testers.  
• Adding a requirement to refill tanks with fresh fuel 15 days prior to ending 
preconditioning is necessary to ensure permeation rates are not suppressed by conditions that do not reflect real -world conditions. As fuel soaks in the tanks, 
the more volatile  constituents evaporate more quick ly, and therefore the fuel 
level and permeation rate change  over time. To ensure fully saturated fuel tank 
walls and emission rates comparable to real -world conditions , fuel should  be 
replaced before ending preconditioning. CARB staff proposes refilling the tank 15 days before the end of preconditioning for two reasons. The first is that it 
represents a periodic replacement of fuel in equipment that would occur as fuel 
is consumed due to its use. The second is that testers at tempting to accomplish 
accelerated preconditioning could conduct two permeation tests separated by 
15 days according to the procedure in § 12 of TP -901 when attempting to 
accomplish accelerated preconditioning. The proposed requirement, “ The fuel 
tank must  not be empty for more than 15  minutes” during the refueling  
263 process, is necessary to ensure fuel tank walls remain fully saturated. The 
proposed 15 -minute maximum time the fuel tank is allowed to be empty is 
consistent with the 15- minute maximum time allowed by the current 
requirements in § 10(a). 
§ 10. Sealing Procedure  
Purpose. The Proposed  Amendments detailed  in Appendix  C include six changes in 
this section:  
• The first removes the requirement for  tanks to be equilibrated to 40 ± 2 °C for a 
minimum of two hours before being sealed. This change would result in tank s 
being tested immediately after sealing.  
• The second adds the text “ (except section 8.1(a)) ” to the requirement to seal 
each tank with the same fuel cap used for the durability demonstration and preconditioning procedure.  
• The third removes the option for testers to seal a test fuel tank “by fusion welding a coupon over the fuel fill neck opening to make a seal .” This change 
would result in  only one option for sealing a test fuel tank:  use of the same fuel 
cap used for the durability demonstration and preconditioning procedure.  
• The fourth removes the text descri bing methods for sealing fuel tanks other 
than with the fuel cap, to ensure a consistent procedure for sealing all fuel tanks for permeation testing. This will also ensure emissions measured in certification tests better represent real -world fuel tank permeation emissions.  
• The fifth makes more specific the existing procedure to prepare a reference 
tank, as indicated by strikeout and underline in the following text  in § 10(b)(2): 
“Fill the reference tank with enough glass beads (or other inert material) so the 
mass of the reference tank is a pproximately the same as the test fuel tanks 
greater than the mass of the lightest test fuel tank and less than the mass of the 
heaviest test fuel tank  when filled with fuel.  Considering the performance 
characteristics of the balance to be used, use good engineering judgment as 
defined in 40 CFR Part 1060.801 to determine how similar the mass of the 
reference tank needs to be to the mass of the test tank. ” 
• The sixth modifies the instructions for sealing the reference tank to require use of a production fuel cap identical to the fuel caps used to seal the test fuel tanks.  
Rationale. These changes are necessary  to ensure  permeation  testing  produces  the 
accurate  results necessary  to prevent  an incorrect determination  of compliance  with 
the evaporative  emission standards.  An incorrect compliance  determinatio n could  lead 
to excess emissions from  certified  engines.  The specific  rationales  for each  of the 
Proposed  Amendments to § 10 are as follows:  
• The first proposed change, removing the requirement for  tanks to be 
equilibrated for two hours, is necessary to prevent inaccurate permeation test  
264 rates. Allowing unsealed tanks filled with fuel to sit at elevated temperature for 
an extended time allows evaporation of the fuel to occur, which may result in an 
inaccurate, lower permeation test emission rate  that does no t reflect real -world 
conditions .  
• The second, third, and fourth proposed changes, which result in only one 
option for sealing the tanks (use of the production fuel cap  used for  the 
durability demonstration (except section 8.1(a)) and preconditioning procedure ), are necessary to ensure more accurate test emission rates. Using 
the production volume fuel cap on the fuel tank for the duration of the test simplifies the procedure and provides testing that better reflects  real-world 
storage and operation conditions, and therefore produces  more accurate test 
emission rates, which is necessary to ensure certified equipment does not result in excess emissions.  Testing fuel tanks in a configuration that more closely 
matches the configuration on a piece of equi pment may improve compliance 
rates of engines with existing diurnal emission standards.  Sealing fuel tanks with 
a coupon of fuel tank material and a fusion welder or another method results in 
liquid or vapor leaks in some cases. Sealing with a fuel cap would prevent such 
problems and enable testing to be completed more quickly.  
• The fifth proposed change, to provide specific constraints for the reference fuel 
tank mass , is necessary to improve clarity and consistency for those 
implementing  the procedure , whi ch increase s clarity for those reviewing the 
data, and better ensures accurate test emission rates and evaporative emission 
compliance determinations . 
• The sixth proposed change, to require a tester to seal the reference tank with  a 
production fuel cap identical to the fuel caps u sed to seal the test fuel tanks, is 
necessary for consistency with the requirement to require all fuel tanks to be sealed with production fuel caps used for the durability demonstration (except 
section 8.1(a)) and preconditioning pr ocedure . 
§ 11. Gravimetric Permeation Test  
Purpose. The Proposed  Amendments detailed  in Appendix  C include four types  of 
changes  in this section:  
• The first removes the  word “optional” in §  11(a)(2) and (8) as it pertains to 
recording relative humidity befo re weighing each seal test fuel tank. The 
change would make it a requirement for testers to measure and record relative humidity.  
• The second modifies the text in §§ 11(a)(2) and (8) regarding how to measure 
and record the mass of the reference tank and ea ch of the test tanks, so that 
the mass of every  fuel ta nk is measured and recorded (rather than differences 
between the reference tank and test tanks).   
265 • The third adds text to §  11(a)(2) to require the tanks to be weighed within 
15 minutes of sealing, compared to the current requirement,  “directly after 
sealing.”  
• The fourth replaces the word “Record” with “Calculate” in the first sentence of 
§ 11(a)(9), “Record the difference in mass between the reference tank and each 
test fuel tank for each daily measurement .” 
Rationale. These changes are necessary  to improve  the test procedure  to better 
ensure the accuracy of permeation  test results,  which  is necessary  to prevent  an 
incorrect determination  of compliance  with the evaporative  emission standards  and 
prevent  excess emissions from  certified  engines.  The specific rationales  for each  of the 
Proposed  Amendments to § 10 are as follows:  
• Because natural moisture in the air can be absorbed and desorbed from fuel 
tank walls, it is necessary  to require that rela tive humidity data be recorded to 
enable the tester and data reviewer to consider all elements that may affect results.  
• Measuring and recording the reference fuel tank and test fuel tank mass (rather 
than differences between the reference tank and test tanks) is necessary to 
simplify the method, improve clarity and accuracy, and  provide information 
necessary for review of the data. For example, it is necessary to record the mass 
of each test fuel tank and the reference tank to confirm the mass of the refer ence tank is greater than the mass of the lightest test fuel tank and less 
than the mass of the heaviest test fuel tank . 
• Providing a specific 15 -minute maximum time for weighing the fuel tanks after 
sealing them is necessary to ensure no excessive delay oc curs between sealing 
the fuel tanks and weighing them. If an excessive delay were to occur, the mass 
measurements could be biased low, which would result in permeation test rates 
that were biased low and certification of engines with emissions that exceed the evaporative emission standards.  The proposed 15- minute maximum time 
allowed to weigh the fuel tanks is consistent with the 15- minute maximum time 
allowed by the current requirements in § 10(a) and proposed for §  9, and allows 
a reasonable amount of tim e for completing procedural tasks without 
introducing an unreasonable amount of uncertainty in the test calculations.  
• Replacing the word “Record” with “Calculate” in the first sentence of § 11(a)(9) 
is necessary to improve the accuracy and clarity of the description of the action 
that must be performed. T he difference in mass between the reference tank 
and each test fuel tank for each daily measurement must be calculated rather 
than only recorded , given how the Proposed Amendments modify the weighing 
proced ure in §§  11(a)(2) and (8). Under the Proposed Amendments to 
§§ 11(a)(2) and (8), the reference tank and test tanks would be weighed each 
day—the balance would not be tared with the reference container on it —and 
the difference in mass between the reference  tank and each test tank would be 
calculated each day.   
266 § 12. Permeation Test with Flame Ionization Detector  
Purpose. The Proposed Amendments add l anguage  to § 12(a)(2), as indicated by 
underlined text in the following sentence, to specify that the fuel tank must be placed 
in the enclosure within 15 minutes of sealing : 
“Place  the fuel tank in an enclosure meeting  the requirements of section  4 of 
TP-902 that is equilibrated to 40 ± 2 °C, and close  the enclosure within  
15 minutes  of sealing the fuel tank as specified  in section  10 of this procedure .”  
Rationale . This change is necessary to ensure no excessive delay occurs between 
sealing the fuel tanks  and placing them in the test enclosure to begin the permeation 
test. If an excessive delay were to occur,  the measurements of react ive organic gas 
emissions from the fuel tank using the flame ionization detector could be biased low, 
which would result in permeation test rates that were biased low and certification of engines with emissions that exceed the evaporative emission standards. The proposed 15-minute maximum time allowed to enclose fuel tanks is consistent with the 
15-minute maximum time allowed by the current requirements in §  10(a) and 
proposed for §§  9 and 11, and allows a reasonable amount of time fo r completing 
procedural tasks without introducing an unreasonable amount of uncertainty in the test calculations.  
§ 16. Figures  
Purpose. The Proposed  Amendments include the following four changes to “Figure 1. 
Data  Sheet.”  
• The first removes the text “ Water  Bath Test (pass/fail): ” 
• The second replaces “weight” with “mass” in the “Full Tank Data” and 
“Reference Tank” table column headings  
• The third removes the weight symbols  from the column headings of both tables  
• The fourth removes the equation for weight l oss at the bottom of the “Full Tank 
Data” table  
Rationale . These changes are necessary to provide consistency with regulatory 
amendments approved in 2016 and to improve accuracy. The Proposed Amendments 
remove the text “ Water Bath Test (pass/fail): ” becau se the water bath test 
requirement was removed from the test procedure by amendments approved in 2016. 
Using the term  “mass” is more accurate  than “weight” and provides  consistency with 
the Proposed Amendments to earlier sections of this test procedure and  other CARB 
procedures. Due to amendments made in 2016, the equation on the data sheet  to 
determine weight loss is obsolete as are  the weight symbols used in the equation and 
table column headings .  
267 D. TP-902, Test Procedure for Determining Diurnal Emissions from Small 
Off-Road Engines  
This section provides a summary, purpose, and rationale for each Proposed 
Amendment to “Small Off -Road Engine Evaporative Emissions Test Procedure, 
TP-902, Test Procedure for Det ermining Diurnal Emissions from Small Off -Road Engine 
Fuel Tanks” (TP -902). The SORE evaporative emission regulations require the use of 
TP-902 to determine the diurnal and resting loss evaporative emissions from small off -
road engines.  This test procedure is incorporated by reference in Title 13, CCR, 
§ 2758. Appendix D of this Staff Report provides the full language of this test 
procedure with Proposed Amendments shown in strikeout and underline formatting.  
Global A mendments throughout TP-902 
Acronym Chan ge 
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before  “Air Resources Board ,” for consistency with recent CARB 
document style practices designed to improve clarity. 
Rationale . This change reflects the California Air Resources Board’s recent change to, 
and preferred use of, the acronym “CARB” versus the prior acronym, “ARB,” and the 
entire agency title, “California Air Resources Board.”  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents accessible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines.  
Table of Contents Change  
Purpose. The Proposed Amendments change the formatting of section titles and text 
in all capital letters to mixed case to aid in making documents accessible for everyone, 
including people with visual impairments and assistive technology users. In addition, the Proposed Amendments adjust p age numbers to accommodate added or removed 
text throughout TP-902. Amendments to the Table of Contents reflect these changes. 
The Proposed Amendments also change “List of Tables and Figures” to “List of 
Table s, Figures,  and Attachments ” for accuracy because there is one of each in the list 
and the list includes an attachment.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines. Amending the page numbers and Table of Contents 
list title is necessary for accuracy and to prevent confusion for the reader.   
268 “Diurn al” Phrase Changes to Incorporate “Hot Soak” Emissions  
Purpo se. As described  in Chapter  II of this Staff Report  and detailed in the following 
sections,  the Proposed  Amendments incorporate  “hot soak”  emissions into the 
evaporative  emission standards  for SORE.  To support  the inclusion of the “hot soak”  
emissions,  the Proposed  Amendments  make  these phrasing  changes throughout  the 
regulations:  
• Change “Diurnal” to “Evaporative” in the title of TP -902, as identified with the 
strikeout and underline text:  
“Test Procedure for Determining  Evaporative  Diurnal  Emissions from 
Small Off -Road Engines”  
• Change “diurnal and resting loss evaporative emissions” to “hot soak, diurnal, 
and resting loss evaporative emissions;”  
• Change “diurnal emission standard” to “hot soak plus diurnal emission standard;”  
• Change “24- hour diurnal” to “hot soak and 24- hour diurnal;”  
• Change “diurnal emission test” to “evaporative emission test;” and  
• Change “diurnal emissions” to “hot soak and diurnal emissions,” or “evaporative emissions,” depending on the context of a particular sentence.  
Rationale . This change is necessary to provide consistency with the Proposed 
Amendments to the evaporative emission standards specified in § 2754. Currently, the 
evaporative emission standards only apply to the 24 -hour diurnal cycle. However, 
some engines tested by CARB have met the 24- hour diurnal emission standard, but 
had hot soak emissions several times higher than the diurnal emission standards. In 
order to control these emissions  that reduce the expected benefits of the emission 
standards, it is necess ary to change §  2754 to incorporate hot soak emissions into the 
evaporative emission standards. The Proposed Amendments update text throughout the regulations, including TP -902, to reflect this change. The purpose and rationale 
section for §  2754(a)  in sec tion B of this chapter provide additional information about 
hot soak emissions and the need for the amendments to the evaporative emission regulations.  
Temperature Change  
Purpose. The Proposed Amendments add temperature “40.6 °C” to references of the 
one-hour hot soak in §§ 3, 5, and 5.2 because it may optionally be performed at 
40.6°C to match the maximum temperature of the diurnal profile  and to provide 
greater purging of passively -purged carbon canisters . 
Rationale . This change is necessary because the a lternative higher hot soak 
temperature enables passively -purged carbon canisters to experience a greater 
amount of purging during the forced cooling. References to the one -hour hot soak  
269 include the alternate temperature to be consistent with the procedure.  The optional 
temperature of 40 .6 °C  for the hot soak test is also consistent with the required 
temperature for the hot soak test for motor vehicles in the “California Evaporative 
Emission Standards and Test Procedures for 2001 and Subsequent Model Motor Vehicles.”  
Definition of Terms  
Purpose. The Proposed Amendments change “ authorized representative or 
designate” to “ authorized representative or designee” to correct a spelling mistake in 
the definition of the term “Executive Officer.”  
Rationale . California  Administrative Law (Title  1, CCR, § 16(a)(4)) requires that 
California regulations be free of spelling errors. The change to correct the spelling of designee is necessary to provide clarity for readers and does not affect any requirements for SORE certifi cation and testing.  
§ 2. Pre-Certification Requirements  
§ 2.1(b). Pressure Test  
Purpose. The Proposed  Amendments to this section  include the following  changes:  
• The first c orrects a typographic error by replacing the text “The Pressure test” 
with “A pressure test” in the first sentence of the first paragraph.  
• The second divides the first paragraph into three paragraphs, with the second 
and third paragraphs inset and labeled as subsections (1) and (2) to better delineate the different steps of the pressure test.  
• The third m odifies text to specify the pressure test shall be performed on fuel 
tanks without fuel and prior to any other durability testing or preconditioning. The current regulations specify that the pressure test shall be performed prior to any preconditioning of the fuel tank.  
• The fourth provides additional instructions to meet an existing requirement to 
determine a fuel tank system’s pressure and vacuum limits. The current regulations require a manufacturer to: “Determine the fuel tank system’s design pressure and vacuum limits under normal operating and storage conditions considering the influence of any associated pressure/vacuum relief components. ” However, the current regulations do not specify how to make 
this determination. The Proposed  Amendments add the following text to 
describe the procedural steps and equipment to be used, including steps to measure and record  the maximum and minimum pressure limits of the test fuel 
tank, which is necessary to determine  the pressure and vacuum limit s required 
for the next Proposed Amendment.  
o “To do this, measure the pressure limits using a fuel tank from an 
evaporative emission control system that is not used for any other  
270 portion of this test procedure by installing a pressure transducer in the 
fuel tank. With the exception of the use of the pressure transducer and 
connection to a carbon canister, as applicable, the fuel tank and fuel tank 
configuration used for these pressure measurements and the evaporative 
emission control system in which it is used shall be identical to those 
used  on the engine tested in the remainder of this test procedure. Using 
compressed air of no less than 21 °C, pressurize the fuel tank with 
compressed air, seal the fuel tank, and measure the pressure every 
second for 5 minutes. Use a vacuum pump to draw a vacuum in the fuel 
tank, seal the fuel tank, and measure the pressure every second for 5 
minutes. Record the maximum and minimum pressure measurements on 
the test report. ” 
• The fifth adds a new provision to the newly labeled  subsection (1): “ Subsection 
(2) of this test is not required if the fuel tank pressure does not exceed a gauge 
pressure of + 1.0 kPa for at least one minute when pressurized and the fuel tank 
vacuum does not exceed a gauge pressure of – 1.0 kPa for at lea st one minute 
when a vacuum is drawn in the fuel tank .” 
• The sixth removes this current provision from the newly labeled subsection (2): 
“If the fuel tank ha s no features that would cause positive or negative pressure 
to accumulate during normal operation o r storage, then a pressure test is not 
required. ” 
Rationale. The rationales  for the Proposed  Amendments to § 2.1(b)  are as follows:  
• The first and second Proposed Amendments are necessary to improve clarity 
and prevent confusion for testers, better ensuring  correct completion of the 
procedural steps.  
• The third change, to require p erform ance of  a pressure test without fuel and 
prior to any other portion of the durability demonstration or preconditioning of the fuel tank, is necessary to further clarify the existing requirement to perform 
a pressure test prior to any preconditioning of the fuel tank. Preconditioning starts to occur when fuel is introduced into the fuel tank, so the existing requirement would preclude performance of a pressure test if fuel were in the fuel tank. However, some manufacturers have submitted test reports that 
indicated a pressure test was performed during preconditioning, which 
indicates that those pressure tests were conducted inconsistent with the necessary procedures that ensure accurate pressure test readings. Thus, this change is also necessary because the presence of fuel in the fuel tank could interfere with the pressure test. Performing a pressure test with fuel in the fuel 
tank would also result in the repeated introduction of air into the fuel tank and 
removal of fuel vapors from the fuel tank. Over the course of the 10,000 cycles required for the test, a significant amount of fuel vapors could be removed from the fuel tank, degrading the fuel and resulting in test results that would not represent real -world permeation emissions from fuel tanks.   
271 • The fourth change, to provide additional instructions, is necessary to provide 
the clarity and consistency necessary to ensure different testers use a consistent 
approach known to pro vide accurate test results, which is necessary to ensure 
that engines determined to be in compliance with emission standards assessed using TP -902 are indeed compliant and do not result in excess emissions. In 
addition, adding explicit instructions to meas ure and record the pressure limits 
is necessary to provide the information needed to determine whether the pressure test may be omitted, per the Proposed Amendment described next .  
• The fifth change is necessary because it improves the reliability of the 
determination that a pressure test may be omitted by providing explicit, 
measurable criteria for determining whether a pressure test may be omitted, 
rather than relying on a subjective assessment, which in turn improves safety and the certainty of later test  results. If a pressure test is omitted 
inappropriately (e.g., the visual assessment of the physical fuel tank and its 
design schematics does not detect that a fuel tank indeed has features that 
would cause positive or negative pressure to accumulate), the n two negative 
consequences could occur. First, excess pressurization or vacuum could result in unsafe conditions for testers, and second, hot soak and diurnal emission test 
results may not be valid. Fuel tanks that pressurize to a greater extent in real -
world use than in certification tests could have higher permeation or venting 
emissions. The result could be higher emissions from SORE than are expected based on certification test results.  The Proposed Amendments would allow 
testers to omit the pressure test if the fuel tank pressure measurements are not higher or lower than the gauge pressure range of + 1.0 to – 1.0 kPa for more 
than one minute. This pressure range is based on discussions with manufacturers, who have indicated that fuel tanks that are connected to carbon canisters often experience minimal pressure changes. Using these criteria would enable testers to determine based on pressure measurements whether a fuel tank has any features that would cause positive or negative pressure to 
accumulate  during normal storage and operation, rather than rely on a 
subjective visual assessment .  
• The sixth change, remove the provision “If the fuel tank ha s no features that 
would cause positive or negative pressure to accumulate during normal 
operation or storage, then a pressure test is not required,” is necessary to avoid 
unnecessary and redundant effort, and prevent confusion. The fifth change described a bove provides an improved method for determining whether a fuel 
tank ha s features that would cause positive or negative pressure to accumulate 
during normal operation or storage . 
§ 2.1(e). Ultraviolet Radiation Exposure 
Purpose. The current regulations specify: “ A sunlight -exposure test shall be performed 
by exposing each test engine or equipment unit to an ultraviolet light of at least 
24 W·m-2 (0.40 W·hr·m-2·min-1) for at least 450 hours. Alternatively, each test engine or 
equipment unit may be exposed to  direct na tural sunlight for at least 450 daylight  
272 hours. ” The Proposed Amendments add language that specifies a tester must 
measure and record ultraviolet (UV) light intensity at least every hour .  
Rationale . This change is necessary because t emperature changes in the test area 
throughout the day may cause the UV light intensity to vary. Measuring and recording 
hourly UV intensity values provides documentation of compliance with the testing 
requirement for at least 450 hours of UV light exposure above the required intensity. In addition, such hourly tracking will better enable testers to make timely adjustments as needed to ensure UV light intensity remains at the appropriate intensity throughout 
each day . This change requires testers to verify they are complying with the existing 
requirement for UV light intensity. Exposure to sunlight or other sources of UV light can degrade materials in the evaporative emission control system, reducing their ability to resist permeation. If the intensity of the UV light d oes not meet the minimum 
requirement, the effect of the exposure on permeation emissions would be reduced and certification test results would not represent real -world emissions.  
§ 2.1(f). Fuel Cap and Tether Spill Test  
Purpose. The Proposed Amendments add a new subsection 2.1(f) to set requirements 
for a new fuel cap and tether spill test  with specific instructions for filling the fuel tank, 
installing and loosening the cap, fully extending the tether within a specified 
timeframe, and reporting any drip ping, spraying or leaking of fuel from any part of the 
fuel cap or tether.  
Rationale . This change is necessary to ensure tether  and fuel cap designs do not cause 
excess evaporative emissions. The evaporative emission regulations in Title 13, CCR, 
§ 2756 r equire fuel caps for fuel tanks used on engines with displacement greater than 
80 cc  to be secured to the fuel tank, equipment or engine with a tether.  This prevents 
fuel caps from falling and becoming damaged or dirty. It also prevents them from 
being los t, which could lead to excess emissions from the fuel tank if the cap is not 
replaced. Some fuel  caps are equipped with internal tethers, i.e., with tethers that are 
attached to a location inside the fuel tanks. Other fuel caps incorporate fuel gauges that extend into the fuel in the fuel tank or otherwise come into contact with liquid 
fuel inside the fuel tank. During evaporative emissions compliance testing and other observations of engines, CARB staff have observed fuel spilling or dripping from 
several pieces of equipment when the fuel cap was removed. Based on these 
observations, CARB staff concludes that there is greater likelihood that these tethers 
and fuel caps may cause users of SORE equipment to spill or drip fuel when removing a cap from the fuel  tank, thereby creating excess emissions neither captured in current 
test procedures nor reflected in CARB’s emissions inventory. Emissions from spillage are not measured in the test procedures because no spillage is permitted by the regulations. Spilled f uel often evaporates quickly, but it can also pollute soil or water, 
where it may not evaporate entirely. Once spilled fuel has evaporated, it can 
negatively impact air quality. Therefore, it is necessary to amend the test procedures 
to ensure that fuel caps and tethers are designed to prevent fuel spillage. It is also  
273 necessary for certification applicants to include information in their applications to 
show that their engines meet relevant standards.  
This test simulates an equipment user removing the fuel  cap to check the fill level or 
add fuel. Some users might drop the fuel cap after removing it, allowing it to hang 
from the tether. Others may hold the fuel cap after removing it. However, the 
proposed instructions for this test will ensure a uniform proc edure for the varying 
designs of fuel caps and tethers used on SORE fuel tanks.  
§ 2.2. Canister Working Capacity  
Purpose. The current regulations specify: “ For evaporative emission control systems 
that use a carbon canister and do not pressurize the fuel t ank, the carbon canister 
must have a working capacity of at least 1.4 grams of vapor storage capacity per liter of fuel tank nominal capacity for tanks greater than o r equal to 3.78 liters, and 
1.0 grams of vapor storage capacity per liter of fuel tank nominal capacity for tanks 
less than 3.78 liters. ”  
The Proposed Amendments change “nominal capacity” to  “total capacity” to require 
that the total capacity of the fuel tank  must be used for calculating carbon canister 
working capacity for these types of evap orative emission control systems. Per Title  13, 
CCR, § 2752, “nominal capacity” means the volume of fuel indicated by the manufacturer that represents the maximum recommended fill level.  In contrast, total 
capacity is the total internal volume of the fuel tank, which includes space occupied by fuel vapor.  
Rationale . This change is necessary to  ensure carbon canisters are sized properly to 
account for the total  vapor space in the fuel tanks, particularly in cases where the total 
capacity of the fuel tank is significantly larger than the nominal capacity.  An 
insufficiently- sized carbon canister may not control venting emissions from a fuel tank 
effectively. CARB staff demonstrated the effective control of venting emissions using carbon canisters with 2.0 grams  of vapor storage capacity per liter of fuel tank total 
capacity, as described in the 2003 Staff Report for the adoption of the current SORE 
emission standards (CARB, 2003). The working capacity requirements proposed in 
2003 were modified based on input from manufacturers. Those modifications resulted in the current working capacity requirements. The nominal capacity and total capacity of a fuel tank are often equivalent or nearly equivalent. However, in some cases, the 
total capacity is significantly greater than the nominal capacity. In such a case, the 
carbon canister may not sufficiently control venting emissions. CARB staff have found that the nominal capacity indicated by manufacturers in a certification application often does not match the recommended  fill level in the user’s manual for the engine, 
which can increase the likelihood that the carbon canister will not effectively control venting emissions.   
274 § 2.4. Running Loss Emission Control Test [newly proposed section]  
Purpose. The Proposed Amendments add a new subsection, “2.4 Running Loss 
Emission Control Test,” to specify instructions for the existing requirement for 
certification applicants to demonstrate that running loss emissions are controlled from 
being emitted into the atmosphere. Per Title  13, CCR, § 2752(a)(27), “running l oss 
emissions” means evaporative emissions from a small off -road engine that occur while 
it is being operated.  The Proposed Amendments would allow certification applicants 
to select one of two methods to demonstrate that running loss emissions are controlled from being emitted into the atmosphere . 
Rationale . This change is necessary to provide clear and consistent directions for 
applicants for how to demonstrate control of running loss emissions, and  to simplify 
CARB review of applications. The SORE evaporative emission regulations in § 2754(b)(1) already require applicants certifying engines or equipment to comply with 
the diurnal emission standards to submit a determination in the certification 
application that running loss emissions are controlled from being emitted into the 
atmosphere , but do not specify a test procedure . In addition, the current version of 
TP-902 does not provide a test sequence for demonstrating control of running loss 
emissions.  The Proposed Amendments to § 2754 would require applicants to follow 
one of the two methods in this newly proposed procedure in § 2.4 for their  
demonstration. The two methods in this procedure are based on methods manufacturers have used to demonstrate running loss emission control.  
§ 3. General Summary of Test Procedure  
Purpose. The current regulations in § 3 refer to Title  13, CCR, “section 2752 (a)(7)” for 
the definition of “evaporative e missi on control s ystem.” The Proposed Amendments 
change the subsec tion r eference number from (7) to (9) so that the text continues to 
refer to the definition of “evaporative e missi on control system.”  
Rationale . This change is necessary to provide consistency with the Proposed 
Amendments to § 2752(a)(7), which change the subsection number of the 
“evaporative e missi on control s ystem”  definition from (7) to (9) to accommodate the 
proposed addition of two new definitions earlier in §  2752(a) .  
§ 4. Instrumentation  
Purpose. The Proposed  Amendments to this section  include the following  changes:  
• Add “Title 40 of the Code of Federal Regulations” to define the acronym 
“CFR”  in the first paragraph of §  4. 
• Add “40 CFR” before the text “§86.117- 90(a)(1) through (a)(6)”  in § 4.2.1.  
• Add a space between each temperature value and “ °F” where currently there is 
no space in the second, third, and fifth paragraphs in § 4.1.   
275 • Add a  space between “±” and “2.0 inches” at the end of the sixth paragraph in 
§ 4.1. 
• Add a new subsection, “4.3 Other Instruments and Equipment ,” to establish 
require ments for equipment calibration frequency and minimum balance 
sensitivity, specified by the following text:  
“All instruments and equipment used in this Test Procedure, TP -902, 
shall be calibrated at the time interval specified by the manufacturer or 
more o ften as needed per manufacturer instructions (e.g., if equipment 
undergoes repair).  
For mass measurements more than 6,200 grams, the minimum sensitivity of the balance must be 0.1 grams. For mass measurement between 1,000 and 6,200 grams, the minimum sensi tivity of the balance must be 
0.01 grams. For mass measurements less than 1,000 grams, the minimum 
sensitivity of the balance must be 0.001 grams.  
The balance shall be calibrated annually per the balance manufacturer’s 
instructions, or more often as needed per the manufacturer instructions 
(e.g., if the balance is moved), using Système International  d'Unités  (SI)-
traceable mass standards through National Institute of Standards and 
Technology (NIST) or another member of the Mutual Recognition 
Arrangement of  the Comité International des Poids et Mesures 
(CIPM  MRA). The SI -traceable mass standards shall be calibrated annually 
by an independent organization or more often as needed.”  
Rationale. The rationales  for the Proposed  Amendments to § 2.1(b)  are as follow s: 
• Addition of the definition of “Title 40 of the Code of Federal Regulations” at the beginning of § 4, and “ 40 CFR” before the section number in § 4.21, is 
necessary to provide the full reference information needed by testers and to provide consistency wi th reference formatting elsewhere in the test procedure.  
• Addition of a space between “±” and “2.0 inches” in §  4.1 is necessary to 
provide consistent formatting throughout the procedure, which improves readability for testers.  
• Addition of requirements for  equipment calibration frequency and minimum 
balance sensitivity is necessary to ensure test data accuracy and precision. 
Specifying that instruments and equipment shall be calibrated more often as 
needed per manufacturer instructions is  necessary to provide certainty for 
testers who need to calibrate instruments or equipment more often and to 
ensure that instruments and equipment are properly calibrated and produce valid data. Accurate and precise data are necessary to ensure that engines 
determined to be in compliance with emission standards assessed using TP -902 
are indeed compliant and do not result in excess emissions. Calibration and 
sensitivity requirements specific to balances are necessary because the Proposed Amendments that add instructions for ap plicants to demonstrate  
276 control of running loss emissions (in a newly proposed section 2.4) require the 
use of a balance with sensitivity adequate to determine whether the mass of a 
carbon canister increases during the running loss test. Including SI -trace able 
standards provides consistency with current practice.  The requirements to use 
SI-traceable mass standards, and for annual calibration of those standards by an 
independent organization, is consistent with current industry practice and is 
necessary to allow flexibility for manufacturers around the wo rld to use other 
recognized international standards while still maintaining the consistency necessary to ensure test data accuracy, precision, and comparability to the emission standards, as well as a level p laying field amongst manufacturers. 
These instructions are based on those in TP -901 and Attachment  1 to TP -902 
and are consistent with standard laboratory practices to ensure collection of valid data.  
§ 5. Test Procedure  
Purpose. The Proposed Amendments remove the following sentence from the first 
paragraph of §  5: “The equipment shall be approximately level during all phases of the 
test sequence to prevent abnormal fuel distribution. ” 
Rationale . This change is necessary to avoid confusion for testers and  to provide 
consistency with t he Proposed Amendments to § 5.2 that would require a tilt test. A 
slosh test  involves rocking the engine 15 degrees back and forth, so equipment will 
not remain level throughout testing. The proposed tilt test involves tilting  the test unit 
90 degrees in each of three directions.  
§ 5.1. Evaporative Emission Control System Precond itioning  
Purpose. The current regulations in this section  specify  the steps for preconditioning  
the evaporative  emission control  system  prior to the hot soak and diurnal  emission 
tests.  The current regulations include these procedural  requirements:  
“The  purpose  of the preconditioning  period  is to introduce  gasoline into the 
evaporative  emission control  system  and precondition  all evaporative  emission  
control  system  components.  Precondition  the evaporative  emission control  
system  by filling the fuel tank to its nominal  capacity with fresh  test fuel as 
specified  in Section  6 of this procedure.  After  filling the tank,  start the engine  
and allow it to run at maximum governed  speed  (unloaded  or blade  load)  for 
approximately five minutes.  Stop  the engine  and add fuel to fill the fuel tank to 
its nominal  capacity.  Soak  the evaporative  emission control  system  at 
30 ± 10°C  for not less than 140 days.  As an alternative,  accelerated  
preconditioning  of the evaporative  emission control  system  can be 
accomplished  by soaking at an elevated  temperature.  Data  documenting  that 
the diurnal  emissions will not increase  with further  preconditioning  must  be 
provided  for tanks  soaked  less than 140 days.  The period  of slosh  testing  and 
ultraviolet radiation  exposure may be considered  part of the preconditioning  
period  provided  the ambient  temperature  remains within  the specified   
277 temperature  range  and each  fuel tank is at least  50 percent full; fuel may be 
added or replaced  as needed  to conduct the specified  durability tests.”  
The Proposed  Amendments detailed  in Appendix  D include six changes in this section:  
• The first requires the tester to measure and record the preconditioning 
temperature at least every five minutes to ensure test units  are soaked at the 
appropriate temperature  throughout preconditioning.  
• The second requires the tester to take steps during preconditioning to ensure fuel remains at nominal capacity to ensure test units  are soaking at their true 
nominal capacity throughout preconditioning.  
• The third requires accelerated preconditioning to be conducted a minimum of 70 days to ensure evaporative emission control system components  are 
saturated with fuel . 
• The fourth a dds instructions necessary to produce acceptable emission data 
that would demonstrate emissions would not increase with further preconditioning, which may be accomplished by performing two hot soak and diurnal tests with hot soak and diurnal emissions measured in the second test no higher than in the first test.  
• The fifth adds the following instructions to provide procedural consistency: 
“Record the fuel fill amount and dates on the test repor t if fuel is added or 
replaced.”  
• The sixth adds the following instructions  to ensure fuel tank walls are fully 
saturated with fresh fuel : “Drain the fuel tank and refill with fresh fuel to 
nominal capacity 15 days prior to ending preconditioning. The fuel tank must 
not be empty for more than 15 minutes. Record the date and time the fuel tank 
is drain ed and refilled with fresh fuel , and record the fuel fill amount  on the test 
report. ” 
Rationale. These changes are necessary  to ensure  hot soak and diurnal  emission  
testing  produce  the accurate  results necessary  to prevent  an incorrect determination  
of compliance  with the evaporative  emission standards.  An incorrect compliance  
determination  could  lead to excess emissions . The specific rationales  for each  of the 
Proposed  Amendments to § 5.1 are as follows:  
• Requiring temperature measurements every five minutes during preconditioning is necessary to ensure temperatures do not fall below required 
thresholds, and is similar to current requirements for the SHED used in hot soak 
and diurnal emission testing, as de scribed in  § 4.1. Temperature influences 
evaporation and therefore evaporative emissions, so in order to verify test units  
are soaking at the appropriate temperature for the duration of preconditioning, 
temperature must be measured and recorded frequently.  Per TP-902 § 4.1, 
current regulations require t emperature to be  measured and recorded every 30 
seconds during hot soak and diurnal emission testing, which indicates it is  
278 feasible and necessary  to measure and record temperature every five minutes 
during preconditioning  as well . CARB staff also expect testers measure and 
record temperature during preconditioning when testing according to the 
current version of TP -902. 
• Requiring the tester to take steps during preconditioning to ensure fuel remains at nominal capacity is necessary because fuel tank material may expand during 
preconditioning or fuel may evaporate , so additional fuel may need to be 
added to ensure fuel tanks remain at true nominal capacity for the duration of 
preconditioning. This could involv e testing staff checking the fill level of fuel 
tanks on a periodic basis.  
• Requiring a minimum soak requirement of 70 days for accelerated 
preconditioning is necessary to  better ensure  preconditioning of the test units 
will not be stopped prematurely (i.e. , before hot soak and diurnal emissions 
stop increasing ). Many manufacturers attempt to accomplish accelerated 
preconditioning of their test units to finish testing sooner. Often, t his involve s 
performing hot soak and diurnal emission tests beginning withi n one month of 
the day that preconditioning starts. Their goal is to end preconditioning as soon as possible. Requiring a minimum of 70 days of preconditioning will continue to allow accelerated preconditioning while decreasing the likelihood that a tester  
will improperly determine hot soak and diurnal emissions have stopped 
increasing. U.S. EPA requires a minimum preconditioning period of 70 days for SORE fuel tanks, as described in 40 CFR §  1060.520. CARB requires a minimum 
preconditioning period of 70 days for PFCs, as described in TP -502. The 
proposed minimum preconditioning period for SORE would therefore be 
consistent with the minimum used for testing fuel tanks for U.S. EPA , with 
CARB’s requirements for PFCs, and with the Proposed Amendments to TP -901. 
• Specific instructions for how to produce  acceptable test data that would 
demonstrate hot soak and diurnal  emissions would not increase with further 
preconditioning is necessary to improve consistency for those implementing  the 
procedure , which better  ensures adequate preconditioning time is 
accomplished, increase s clarity for those reviewing the data, better ensures 
accurate emission standards compliance determinations, and better maintain s a 
level playing field among st manufacturers . CARB staff developed  the 
instructions based on data that have been provided by manufacturers to 
document that diurnal  emissions from the engines will not increase with further 
preconditioning.  
• Adding a requirement to record the fuel fill amount  dates during 
preconditioning is necessary for reviewers to verify the procedure is followed correctly and consistently by different testers.  
• Adding a requirement to refill tanks with fresh fuel 15 days prior to ending 
preconditioning is necessary to ensure hot soak and diurnal emission rates are 
not suppressed by conditions that do not reflect real -world conditions. As fuel 
soaks in the test units, the more volatile constituents evaporate more quickly,  
279 and therefore the fuel level and emission  rates change over time. To ensure 
fully saturated evaporative emission control system components  and emission 
rates comparable to real -world conditions, fuel should be replaced before 
ending preconditioning. CARB staff proposes refilling the tank 15 days before 
the end of preconditioning for two reasons. The first is that it represents a 
periodic replacement of fuel in equipment that would occur as fuel is consumed due to its use. The second is that testers attempting to accomplish accelerated 
preconditioning could conduct two  test sequences separated by 15 days 
according to the procedure in TP -902 § 5.2 through § 5.4 when attempting to 
accomplish accelerated preconditioning.  The proposed requirement, “The fuel 
tank must not be empty for more than 15  minutes” during the refueling 
process, is necessary to ensure evaporative emission control system components  remain fully saturated. The proposed 15- minute maximum time the 
fuel tank is allowed to be empty is consistent with the 15- minute maximum time 
allowed by the current  requirements in TP -901 § 10(a).  
§ 5.2. Refueling and Hot Soak  
Purpose. The current regulations in this section  specify  refueling  and hot soak test 
steps.  As defined  by Title 13, CCR,  § 2752(a),  “hot soak emissions”  are evaporative  
emissions  that occur for the one-hour period  following the termination  of engine 
operation . The current  regulations include these procedural  requirements:  
“Following the preconditioning  period,  drain  the fuel tank and refill to 
50 percent of its nominal  capacity with test fuel. For evaporative  emission 
control  systems  that use a carbon  canister,  the canister  must  be purged 
following the preconditioning  period  but prior  to initiating the hot soak test. 
Purging  consists of drawing 400 bed volumes  of nitrogen  or dry air through  the 
canister  at the canister  manufacturer’s  recommended  purge  rate. Operate  the 
engine  at its maximum  governed  speed  for fifteen  minutes.  Immediately place  
the engine in the SHED  enclosure preheated  to 35 °C. Perform a one-hour hot 
soak at a constant  35 °C.” 
The Proposed  Amendments detailed  in Appendix  D include six changes in this section:  
• Add language to specify the timing for refilling the fuel tank and require the 
tester to record the fuel fill amount, date and time on the test report.  
• Add language  to specify different steps for  the purging procedure for 
actively- and passively -purged carbon canisters. Actively- purged carbon 
canisters would be purged with 400  bed volumes of air. Passively -purged 
carbon canisters would  not be manually purged before testing. Instead, 
passively -purged carbon canisters would be purged due to vacuum created in 
the fuel tank when the engine is run in § 5.2 and during forced cooling in § 5.3 
of TP -902. Carbon canisters would be weighed before and aft er purging.  
• Add requirements that establish a new t ilt test. The tilt test consists of tipping a 
piece of equipment 90 degrees in three directions, without tilting toward the  
280 carburetor, and monitoring for leaking fuel. The Proposed Amendments specify 
that the tilt test may be omitted for a test unit with displacement greater than 
or equal to 225 cc if engines from the evaporative family will not be used in 
equipment that is designed to be tilted during operation, transport , 
maintenance,  or storage. Any fuel leaking from any part of the engine or 
evaporative emission control system would constitute a test failure . 
• Add instructions for what to do if e ngines run out of fuel while running at 
maximum governed speed for 15 minutes. The instructions specify the tester  
must restart the test procedure with the fuel tank filled to nominal capacity rather than 50 percent of nominal capacity.  
• Add t emperature specifications for  the SHED enclosure during the hot soak to 
further specify  allowable range  for temperature  variability .  
• Add a  requirement to place the equipment in the enclosure within 180 seconds 
(3 minutes) of engine shutdown to ensure all evaporative emissions are 
captured by the enclosure.  
Rationale. These changes are necessary  to ensure  testing  produces  the accurate  
results necessary  to prevent  an incorrect determination  of compliance  with the 
evaporative  emission standards.  An incorrect compliance  determination  could  lead to 
excess  emissions. In addition,  some  of these  changes are necessary  to eliminate exce ss 
emissions  that come  from  fuel leaks than can occur when some  engines are tilted.  The 
specific rationales  for each  of the Proposed  Amendments to § 5.2 are as follows:  
• The proposed requirement, “The fuel tank must not be empty for more than 
15 minutes” during the refueling process, is necessary to ensure evaporative 
emission control system components  remain fully saturated. The proposed 
15 minute maximum time the fuel tank is allowed to be empty is consistent with 
the 15- minute maximum time allowed by the current requirements in TP -901 
§ 10(a). Adding a requirement to record the fuel fill amount, date and time 
when the fuel tank is drained and refilled  is necessary for reviewers to verify the 
procedure is followed correctly and consistently by different tes ters. 
• Having different steps for  purging actively- and passively -purged carbon 
canisters  is necessary to produce accurate test results given the different 
characteristics of actively- and passively -purged carbon canisters.  The change to 
specify that actively- purged carbon canisters would be purged with “air” rather 
than “nitrogen or dry air” is necessary to account for different canister designs 
and ensure the test procedure allows for purging canisters by drawing ambient 
air into the purge port, as engines do when carbon canisters are installed. 
Passively -purged canisters are designed to purge during normal operation and 
during cooling of the engine. The Proposed Amendments to § 5 of TP -902 
would result in purging  passively -purged carbon canisters in the way that is 
consistent with their design during the test. Measuring the carbon canister mass 
before and after purging is necessary to provide information regarding the  
281 ability of carbon canisters to capture and store venting  emissions until they are 
purged.  
• The addition of a tilt test is necessary to eliminate excess emissions that come 
from fuel leaks when equipment is turned on its side for cleaning, transportation, or storage . CARB staff have observed during testing that f uel 
can spill when equipment is tilted during typical activities, and found that, when 
equipment is tilted , fuel can contact the carbon canister, which must be 
prevented.  Owner’s manuals for some equipment direct users to tilt equipment 
or turn it on its side for certain activities. For example, for a Honda HRC216HXA lawn mower, the owner’s manual directs a user to tilt the mower to the right side for various activities, including blade inspection, oil changes, and cleaning, 
and indicates a loading ramp may  be used to load the mower on a transport 
vehicle (Honda, 2021). Ramps are often used by landscapers to load lawn 
mowers into the beds of pickup trucks. Because it is not practical to store loading ramps that are longer than the bed of a pickup truck, the angle of ramps used by landscapers when leaned against the tailgate is often steep, resulting in significant tilting of the mower as it is pushed up the ramp.  
Other  products,  such as portable  generators  and pressure washers,  are 
designed  to be tilted  for transport.  A user may determine  that it is easier  or 
more  secure to tilt a pressure washer  on its side,  front,  or back  when  securing  it 
in a vehicle.  This could  result  in prolonged  tilting of a piece  of equipment  
without  any fuel spillage. However,  the carbon canister  may be exposed  to 
liquid fuel, or evaporative  emissions could  otherwise increase  without  a user 
having  an indication  other  than the unpleasant  odor  of gasoline.  Some  
equipment,  including  some  models  of lawn mowers,  are designed  to be tilted  
for storage  to save space  in a storage  area.  Handheld  equipment  is often  
designed  to function  in a range  of orientations,  including  upside  down.   
Aside  from  these examples of tilting that is intended  by manufacturers,  users 
are likely to tilt their equipment  for other  reasons,  intentionally  or 
unintentionally,  during  operation,  transport,  maintenance,  or storage.  By its 
nature,  handheld  equipment  is unlikely to be affected  by the tilt test. The tilt 
test may increase  evaporative  emissions of nonhandheld  equipm ent that is not 
properly designed  to meet  the existing requirement  in § 2754(d)  [re-lettered  
to (e) in the Proposed  Amendments]  of the evaporative  emission regulations  to 
install carbon  canisters  in a way that prevents  exposing  the carbon  to water or 
liquid fuel. The proposed  tilt test steps simulate momentary tilting of 
equipment  that a user might perform when operating,  transporting,  
maintaining, or storing  equipment,  and incorporate  feedback  from  
manufacturers.  Leaving  the test unit in each  position  for five minutes would  
ensure momentary tilting would  not cause  fuel to spill or result  in evaporative  
emissions  that exceed  the applicable  emission standard.  The Proposed  
Amendments do not require the tester  to tilt the engine  in the direction  which  
results in the air inlet of the engine pointing downward, because rotating  in this 
direction  is known  to result  in extensive  fuel leakage  for engines that use  
282 float-type carburetors.  The Proposed  Amendments would  require this new tilt 
test for evaporative  families that include models  that may be tilted  during  
typical  activities,  as specified  by the proposed  addition  of this sentence:  “This 
tilt sequence may be omitted  for a test unit with displacement  greater than or 
equal  to 225 cc if engines from  the evaporative  family will not be used  in 
equipment  that is designed  to be tilted  during  operation,  transport, 
maintenance,  or storage. ” This text is carefully  worded to account for the 
existence of equipment  using  engines with displacement  greater  than or equal  
to 225 cc that may be operated  at an angle,  such as mowing  grass  on a slope , 
or may otherwise be tilted . For example, Figure II-4 in Chapter  II of this Staff 
Report  shows an individual  cleaning  under  a riding mower  that has been tilted  
using  a hydraulic jack.  
The current regulations  include requirements  that are expected  to ensure 
emission control  systems  would  not be negatively affected  by momentary tilting 
of the engine.  An example is the requirement  in § 2754(d)  [re-lettered  to (e) in 
the Proposed  Amendments]  of the evaporative  emission  regulations to install 
carbon  canisters  in a way that prevents  exposing the carbon  to water  or liquid 
fuel. 
• The instructions for what to do if e ngines run out of fuel when preparing for the 
hot soak test are necessary to account f or engines with small fuel tanks that may 
have run times of less than 15 minutes at maximum governed speed .  
• The addition of t emperature range specifications for the SHED enclosure during 
the hot soak is necessary to correct an oversight that occurred when  TP-902 
was adopted. TP -902 includes temperature range specifications for all testing. 
However, the hot soak test is performed at a higher temperature than typical 
room temperature. When the SHED door is opened to place the test unit inside, the temperature inside the SHED can drop.  The proposed hot soak 
temperature specifications match those for the hot soak  test for motor vehicles . 
The tolerance for temperature is higher for a hot soak test than for a diurnal 
emission test because of the elevated temperature. The tolerance is highest for 
the first five minutes after the SHED is sealed because the temperature inside the SHED typically decreases after the door is opened.  
• The addition of a  specified maximum time allowed to place  the equipment in 
the SHED enclosure after engine shutdown is necessary  to ensure all 
evaporative emissions during the hot soak period are captured by the 
enclosure. This change is necessary because the Proposed Amendments to 
§ 2754 include hot soak emissions along with diurnal emissions when assessing 
compliance with the evaporative emission standard s.  
§ 5.4. 24- Hour Diurnal Test  
Purpose. The Proposed Amendments add a sentence to the tester to: “ Measure and 
record the carbon canister mass after the diurnal test on the test report.”    
283 Rationale . This change is necessary to provide information regarding the ability of 
carbon canisters to capture and store venting emissions until they are purged.  A 
carbon canister that does not gain significant mass during the diurnal emission test 
may not be functioning properly. That could, for example, be due to exposure of the 
carbon to liquid fuel. If the carbon canister were not weighed after the diurnal emission test, a tester would not have potentially useful information on the 
performance of the  carbon canister.  
§ 6. Test Fuel  
Purpose. The current regulations in § 6 provide:   
“Testing  according  to this procedure  shall be conducted  using  1) LEV III 
Certification  Gasoline as defined  in part II, section  A.100.3.1.2 of the California 
2015 and Subsequent  Model  Criteria  Pollutant Exhaust  Emission Standards  and 
Test Procedures  and 2017 and Subsequent  Model  Greenhouse Gas Exhaust  
Emission Standards  and Test Procedures  for Passenger  Cars,  Light Duty Trucks,  
and Medium -Duty Vehicles , as last amended  Septem ber 2, 2015,  or 2) the fuel 
defined  in 40 CFR Part 1065.710(b)  for general  testing . 
The fuel specified  in part II, section  A.100.3.1.1  of the California 2015 and 
Subsequent  Model  Criteria  Pollutant Exhaust  Emission Standards  and Test 
Procedures  and 2017  and Subsequent  Model  Greenhouse Gas Exhaust  
Emission Standards  and Test Procedures  for Passenger  Cars,  Light Duty Trucks,  
and Medium -Duty Vehicles,  as last amended  September  2, 2015,  may be used  
as an alternative  test fuel to certify fuel tanks  for use on engines  and equipment  
through  model  year 2019. ” 
The Proposed Amendments include two changes to § 6 as follows:  
• Delete the entire second paragraph to provide consistency with current 
regulatory requirements.  
• Add a new unnumbered paragraph with the following text:  
“For engines that are not gasoline- fueled  and that are powered with 
compressed  natural  gas (CNG), propane,  liquefied  petroleum  gas (LPG), or 
liquefied  natural  gas (LNG), testing  according  to this procedure  shall be 
conducted  using  a fuel meeting  the requirements of section  1065.701  of the 
“California Exhaust  Emission Standards  and Test Procedures  for New 2013 and 
Later Small  Off-Road  Engines;  Engine- Testing  Procedures  (Part  1065),”  adopted 
October  25, 2012,  and amended  [insert  amended  date]. ” 
Rationale. The rationales  for the Proposed  Amendments to § 6 are as follows:  
• The first change is necessary to prevent confusion because t he alternative test 
fuel specified in the current regulations was allowed only through MY 2019, so 
is no longer applicable.   
284 • The second change is necessary to specify test fuels for engines that are not 
gasoline- fueled and that are powered with CNG, propane, LPG, or LNG  
because the Proposed Amendments to § 2754.1(b)(3)  allow such  engines to be 
certified to earn evaporative emission credits. Those engines must be tested 
according to TP -902 to be eligible to earn evaporative emission credits, and 
TP-902 does not currently include a fuel option to test them. This change will 
ensure proper selection of test fuels for all engines that are tested according to TP-902. 
Attachment 1 . Procedure for Determining Carbon Canister Performance: 
Durability Demonstration and Working Capacity  
The test p rocedure specified by Attachment 1 is used to evaluate the durability and 
working capacity of carbon canisters used to control evaporative emissions from 
SORE. Working capacity is a defining parameter expressing the mass of organic  
material hydrocarbon equivalent that can be stored in the canister under  controlled 
conditions.  
§ 5. Equipment Calibrations  
Purpose. There are three Proposed  Amendments to this section:  
• Change the coefficient of determination notation from “R2” to “r2” in the first 
paragraph of the section.  
• Chang e the requirement to calibrate the balance using N IST-traceable 
standards to using SI -traceable standards  in the second paragraph of this 
section.  
• Remove the percent symbols (%) from this sentence in the second paragraph: 
“At minimum, the accuracy shall be checked at approximately 80 % percent , 
100% percent, and 120% percent  of the canister’s expected test mass.   
Rationale. The rationales  for the Proposed  Amendments to § 5 in Attachment 1 are as 
follows:  
• Changing the notation from “R2” to “r2” is necessary to reflect common 
convention f or describing the  coefficient of determination  and to provide 
consistency with other CARB test procedures, which helps prevent confusion for 
testers . This change does not affect the current calibration requirements.  
• Requiring SI -traceable standards (which  include NIST -traceable standards) is 
consistent with current industry practice and is necessary to allow flexibility for manufacturers around the world to use other recognized international standards 
while still maintaining the consistency necessary to ensure test data accuracy, 
precision, and comparability to the emission standards, as well as a level playing field amongst manufacturers. Accurate and precise data are necessary to ensure that engines determined to be in compliance with emission standards a ssessed 
using TP -902 are indeed compliant and do not result in excess emissions.   
285 • Removing the percent symbols is necessary to improve readability because 
each percent symbol is followed by the word “percent,” and is therefore 
redundant  and not necessary . Using the word “percent” rather than the symbol 
provides consistency with recent CARB document style practices designed to improve clarity. 
§ 6. Carbon Canister Working Capacity Determination  
Purpose. Section  6 specifies  the testing  steps to establish the canister’s  working 
capacity by repeated  canister  loading and purging.  This procedure  involves  multiple 
cycle s that each  include a 400 bed volume  purge  (specified  in § 6.2), a five minute  
pause (specified  in § 6.3), weighing  the canister (specified  in § 6.4), and then loading 
the canister  with butane mixed 50/50 by volume  with air or nitrogen  to a measured  
breakthrough  (specified in § 6.5). There  are two types  of proposed  changes  to this 
section , and both  are for specifications  in § 6.5. The current regulations in § 6.5 
specify:  
“Load  the test canister  with butane  mixed 50/50  by volume  with air or nitrogen  
until the specified  breakthrough  criterion  has been  met. The canister  load is 
accomplished  by flowing the butane mixture  into the canister  via the tank 
fitting.  The butane  load rates  and breakthrough  criteria  are determined  by 
canister’s  bed volume.  In order  to accommodate  the expected  wide  range  of 
canister  bed volumes  expected  in small  off-road engines,  four ranges of canister  
loading and breakthrough  criteria  are defined:  small (< 99cc),  medium  
(100 to 249cc)  large  (249 to 550cc)  and extra  large  (> 550cc).  The load and 
breakthrough  criteria  are defined  as follows:  
Carbon Canister Bed 
Volume  Small  
< 99cc  Medium  
100 to 
249cc  Large  
 249cc to 
550 Extra Large  
>550  
Butane Load Rate [grams 
C4H10 / hour]  5.0 10.0 15.0 15.0 
Breakthrough limit 
[grams](*)  2.0 2.0 2.0 2.0 
(*) If the canister shows mass loss prior to the 2.0 grams breakthrough then 
an alternate lower breakthrough limit can be used. ”  
The Proposed  Amendments detailed  in Appendix  D include the following  changes  to 
§ 6.5 in Attachment 1: 
• Add the following sentence to specify a tolerance (i.e., allowable range or 
margin of error) for butane load rate of 10  percent  of the specified load rate in 
the above  table provided in §  6.5: “The butane load rate must be within 
± 10 percent o f the specified load rate below .” 
• Improve the notation and spacing in the carbon canister bed volume categories  
in the paragraph text and table in §  6.5 by changing t he small category from  
286 “< 99cc” to “<  100 cc,” the medium category from “100 to 249cc” to 
“≥ 100 cc and <  250 cc,” the large category from “24 9 to 550 cc” [in the 
paragraph text] and “24 9cc to 550”  [in the table]  to “≥ 250  cc and ≤ 550cc ,” 
and the extra  large category from “>  550cc” [in the paragraph text] and 
“>550cc”  [in the table]  to “>  550 cc.” 
• Improve the grammar of the list of carbon canister bed volume categories  in the 
paragraph text by adding a comma after the medium and large categories.  
Rationale. The specific rationales  for each  of the Proposed  Amendments to § 6.5 in 
Attachment 1 are as follows: 
• Specifying a butane load rate tolerance is necessary to minimize the error in the 
calculation of the canister’s working capacity and to ensure the specified load 
rates can be achieved consi stently. Attachment 1 was proposed by industry to 
replace the procedure proposed by CARB staff in 2003 for determining carbon canister working capacity. Unlike other procedures for determining carbon 
canister working capacity, Attachment 1 does not specify a tolerance for load 
rate. Manufacturers have requested the addition of butane load rate tolerance. 
Test reports indicate manufacturers are able to meet the required load rates. However, some manufacturers have indicated difficulty in meeting the load rates. The proposed tolerance would enable testers to consistently meet the required load rates, while minimizing error.  
• Improving the notation and spacing of the carbon canister bed volume categories  in the paragraph text and table, and improving the grammar of the 
category list in the paragraph text, are necessary to better delineate each category, eliminate  ambiguity, and improve readability.  
§ 7. Calculating Results  
Purpose. Section  7 contains only two sentences. The current regulations in §  7 specify: 
“The working capacity is the lower test canister weight gain in grams determined from 
the last two load cycles. The resultant working capacity is expressed in grams of 
C4H10.” The Proposed Amendments add the following new sentence, equation, and 
definitions of the equation variables, before the existing sentences to specify how to 
calculate the butane load rate:  
“The  following equation  shall be used  to calculate  butane  load rate: 
Qb = 3,600 × (mf−mi) + mb
t 
where:  
Qb = butane load  rate (grams  C4H10 per hour)  
3,600  = the number of seconds in one hour  
mf = final carbon canister mass (grams)  
mi = initial carbon canister mass (grams)   
287 mb = breakthrough mass (grams)  
t = duration of load cycle (seconds) ” 
 
Rationale . This change is necessary to provide specificity, en sure consistency, and 
prevent calculation errors. The proposed equation is based on basic physical principl es 
and algebra, along with a conversion factor (3600 seconds per hour) to convert flow 
rate in grams per second to grams per hour. The symbols used in the proposed equation are those used in Figure 1, the Canister Data Sheet, of Attachment  1. This 
change does not affect the calculation of butane load rate, because the method 
specified in the proposed equation is used by testers when determining carbon 
canister working capacity according to Attachment 1. 
§ 9. Figures  
Purpose. Section 9 contains Figure 1, the Canister Data Sheet. The Proposed 
Amendments add the symbol “t” for the column “Duration [seconds]” in the Canister Purge Data and Canister Load Dat a tables and change a column heading from 
“Butane Rate Q
b [g/hr]” to “Butane Load Rate Q b [g/hr].” 
Rationale . These changes are necessary to provide specificity, ensure consistency, and 
prevent calculation errors. The symbol “t” is used in the equation included in the Proposed Amendments to § 7 of Attachment 1. The rate specified in the table in § 6.5 
and calculated in § 7 of Attachment 1 is butane load rate.  
E. CP-902, Certification Procedure for Evaporative Emission Control Systems 
on Small Off -Road Engines  
This section provides a summary, purpose, and rationale for each Proposed 
Amendment to “ Small Off -Road Engine Evaporative Emission Control System 
Certification Procedure, CP -902, Certification Procedure for Evaporative Emissi on 
Control Systems on Engines With Displacement Greater Than 80 Cubic Centimeters” 
(CP-902). The SORE evaporative emission regulations require the use of CP -902 to 
evaluate and certify evaporative emission control systems on SORE to evaporative 
emission standards. This certification procedure is incorporated by reference in Title 13, CCR, § 2753. Appendix E of this Staff Report provides the full language of 
this certification procedure with Proposed Amendments shown in strikeout and 
underline formatting.  
Global Amendments throughout CP -902 
Acronym Change  
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before “Air Resources Board,” for consistency with recent CARB 
document style practices designed to improve clarity.  
288 Rationale . This change reflects the California Air Resources Board’s recent change to, 
and preferred use of, the acronym “CARB” versus the prior acronym, “ARB,” and the 
entire agency title, “California Air Resources Board.”  
“Engine” Phrase Change to Incorp orate “Small Off -Road”  
Purpose. The Proposed Amendments add “small off -road” before “engines” in the 
title to ensure the title accurately represents the procedure.  
Rationale . This change is necessary because a dding “small off -road” before “engines” 
clarifi es that the procedure is for small off -road engines.   
Applicability Change  
Purpose. The current title and text of CP -902 reference engines “with displacement 
greater than 80 cubic centimeters” to differentiate between the applicability of 
CP-901 and CP -902. The Proposed Amendments remove this reference throughout 
CP-902, and add a fourth displacement category to § 4.1 in CP -902 for engines with 
displacement less than or equal to 80 cc, to  include all SORE displacements.  
Rationale . This change is necessary to provide consistency with Proposed 
Amendments to Title  13, CCR, §  2753. Under the Proposed Amendments to § 2753, 
CP-902 would apply to all SORE for MY  2024 and subsequent model years, including 
SORE with displacement less than or equal to 80 cc.  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents accessible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale. Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines.  
Table of Contents Change  
Purpose. The Proposed Amendments change the formatting of section titles and text 
in all capital letters to mixed case t o aid in making documents accessible to everyone, 
including people with visual impairments and assistive technology users. In addition, the Proposed Amendments adjust p age numbers to accommodate added or removed 
text throughout TP-902. Amendments to the Table of  Contents reflect these changes.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines. Amending the page numbers is necessary for accuracy and to avoid confusion for the reader.   
289 “Diurnal” Phrase Changes to Incorporate “Hot Soak” Emissions  
Purpose. As described  in Chapter  II of this Staff Report  and detailed in the following 
sections,  the Proposed  Amendments incorporate  “hot soak”  emissions into the 
evaporative  emission standards  for SORE.  To suppo rt the inclusion of the “hot soak”  
emissions,  the Proposed  Amendments  make  these phrasing  changes throughout  the 
regulations:  
• Change “diurnal emission and design standards” to “evaporative emission 
standards;”  
• Change “diurnal emission rates ” to “hot soak a nd diurnal emission rates”  or 
“hot soak plus diurnal emission rate s,” depending on the context of a particular 
sentence; 
• Change “diurnal emission rate” to “hot soak plus diurnal emission rate;” 
• Change “diurnal emission standard” to “hot soak plus diurnal emission standard ;” 
• Change “diurnal emission standards” to “hot soak plus diurnal emission standards” or “ evaporative emission standards,” depending on the context of a 
particular sentence;  and 
• Change “diurnal emission testing” to “hot soak and diurnal emission testing .” 
Rationale . This change is necessary to provide consistency with the Proposed 
Amendments to the evaporative emission standards specified in § 2753. Currently, the 
evaporative emission standards only apply to the 24 -hour diurnal cycle. However, 
some engines tested by CARB have met the 24- hour diurnal emission standard, but 
had hot soak emissions several times higher than the diurnal emission standards. In 
order to control these emissions  that reduce the expected benefits of the emission 
standards, it is necessary to change § 2753 to incorporate hot soak emissions into the 
evaporative emission standards. The Proposed Amendments update text throughout the regulations, including CP -902, to reflect this change. Section B in this chapter 
provi des additional information about hot soak emissions and the need for the 
amendments to the evaporative emission regulations.  
Design Certification Option Removed  
Purpose. The current regulations in Title 13, CCR, § 2750(b) require manufacturers to 
select one of two allowable options for certification of engines  and state that the 
options are identified in § 2754(a) and in § 2754(b) . Those options are referred to as 
“performance certification” and “design certification. ” Both options require running 
loss emis sions to be  controlled during engine operation, which result s in greater 
evaporative emission reductions. Section  2754(a) specifies the diurnal emi ssion and 
design standards for SORE with displacements greater than 80 cc in Table  1 and 
requires that  diurna l emissions from any SORE with displacement greater than 80 cc 
must not exceed those standards. Section  2754(b ) requires an applicant to submit in  
290 the certification application : (1) a determination that running loss emissions are 
controlled from being emitted into the atmosphere; and (2) either the Executive Or der 
of Certification number approving the fuel lines  pursuant to § 2767.1, or  test data 
showing that all fuel lines meet the permeation requirement of 15 grams of ROG per 
square meter of surface area of the surface in contact with fuel per day  when tested in 
accordance with one of the procedures specified in § 2754(b ). The current regulations 
in § 2754(c) require a manufacturer to choose (1) “performance certification,” and provide diurnal emission test data for the engine or equipment model in the evaporative family that is expected to exhibit the highest diurnal emission rate relative to the applicable diurnal emission standard, in accordance with TP -902; or (2) “design 
certification,” and provide information in the certification application showing that the fuel tank and carbon canister meet the applicable design standards listed in Table 1 of § 2754.  
Under  the Proposed  Amendments,  design certification  would  not be an allowable 
option  for MY 2024 a nd subsequent  model  years  because no design standards  are 
proposed  for MY 2024  and subsequent  model  years.  Consequently,  for consistency  
with these proposed  changes,  the Proposed  Amendments remove  language  
throughout  CP-902 that is specific  to the “design certification”  option . As detailed in 
Appendix  E, the Proposed  Amendments  make  the following changes:  
• Remove text from §  4.1 and § 6 that specifies applicants must submit test 
results (whether or not they were collected according to TP -901, SAE J1737 
(Stab ilized May 20 13), SAE J30, SAE J1527, and  SAE J2996) or Executive Order 
of Certification numbers for fuel tanks, fuel lines, and carbon canisters.  
• Remove text from §  5.6 that specifies the following are among test procedures 
used to determine compliance with the evaporative emission standards: SAE 
J1737 (Stabilized May 2013), SAE J30, SAE J1527, or, only for fuel lines with inner diameter 4.75 mm or less, SAE J2996, and TP-901. 
• Remove text from §  6 that specifies applicants must  include Executive Order of 
Certification numbers applicable to fuel tank model s, fuel line models, and 
carbon canister model s in the evaporative family description s required to be 
included in certification applications, and move text that requires the following information about  each component model : 
For each  fuel tank model:  
o Tank materials, including pigments, plasticizers, UV inhibitors, or other 
additives that are expected to affect control of emissions  
o Gasket material  
o Production method  
o Permeation  barrier 
o Engineering drawings  
For each  fuel line model:   
291 o Materials and methods used to construct the line  
o Permeation barrier 
o Engineering drawings  
The § 6 list of information  required  for carbon  canisters does  not need  
amendment  because it is configured  in a way that list the necessary  information  
even when  the Executive  Order  of Certification  number  option  is removed.  
• Remove the word “certified” from the following text included in the §  7 list of 
items required in the Executive Order of Certification: “ A list of components 
certified  for use with the evaporative family including component 
specifications. ” 
• Remove these three items included in the § 7 list of items  required in the 
Executive Order of Certification:  
o Highest tested final permeation rate (g ROG·m-2·day-1) of the fuel tank 
samples t ested for certification, as calculated in section 14 of TP -901, if 
applicable.  
o Highest tested permeation rate (g ROG·m-2·day-1) of the fuel line samples 
tested for certification, as calculated in SAE J1737 (Stabilized May 2013), 
SAE J30, SAE J1527, or SAE J2996, if applicable.  
o Working capacity (g organic material hydrocarbon equivalent) of the carbon canister as measured in Attachment 1 to TP -902. 
R
ationale . The proposed changes are necessary to provide consistency with the 
Proposed Amendments to § 2750(b),  which are necessary to support the effective 
inclusion of hot soak emissions in the emission standards. The Proposed Amendments 
specify revisions to § 2754(a)  and add a new subsection 2754(d ) that, beginning with 
MY 2024, would require manufacturers to demonstrate compliance with evaporative 
emission standards that incorporate hot soak emissions and to submit data showing 
that hot soak plus diurnal emissions will not exceed the new standards prior to 
certification. Howe ver, the existing design standards in Table 1 of § 2754 have not 
been demonstrated to ensure that hot soak plus diurnal emissions would not exceed 
the newly proposed emission standards. CARB staff solicited information during public 
workshops and other stakeholder meetings regarding design standards that would 
enable engines to meet the proposed emission standards in a way that would make 
design certification effective. CARB staff did not receive such information, but did 
receive comments indicating that ma nufacturers believed design certifi cation was a 
valuable option. The perceived value of design certification for manufacturers did not 
suggest that certifying to design standards would provide sufficient evidence for 
CARB to determine that engines meet the proposed hot soak plus diurnal emi ssion 
standards. Consequently, the Proposed Amendments to § 2750 require manufacturers 
to use performance certification to certify each evaporative family to meet the hot 
soak plus diurnal emission standards for MY 2024 and subsequent model years, and  
292 the Proposed Amendments to CP -902 remove requirements specific to the design 
certification option. Under the Proposed Amendments to §  2753 Certification 
Requirements, manufacturers may continue to follow the current regulations as 
specified in CP -902, amended September  18, 2017, or earlier editions, as applicable, 
for MY 2023 and earlier model years.  
Definition of Terms  
Purpose. The Proposed Amendments change “ authorized representative or 
designate” to “ authorized representative or designee” to correct a spelli ng error in 
the definition of the term “Executive Officer.”  
Rationale . California Administrative Law (Title  1, CCR, § 16(a)(4)) requires that 
California regulations be free of spelling errors. The change to correct the spelling of 
designee is necessary to provide clarity for readers and does not affect any requirements for SORE certification and testing.  
§ 1. General Information and Applicability  
Purpose. The Proposed Amendments change “a” to “an” in the beginning of the first 
sentence of § 1.1, “ Certification of a evaporative emission control system…,” to 
improve grammar.  
Rationale . This change is necessary to correct nonstandard grammar in the previously 
adopted text . California Administrative Law (Title  1, CCR, § 16(a)(4) ) requires that 
California regulat ions be free of grammatical errors. The correction is necessary to 
provide clarity for readers and does not affect any requirements for SORE certification 
and testing.  
§ 3. Optional Evaporative Emission Standar ds 
Purpose. The Proposed Amendments add “through Model Year 2023” to the title of 
this section to specify optional evaporative emission standards would be  available only 
through MY 2023.  
Rationale . This change is necessary to provide consistency with proposed revisions to 
Title 13, CCR, §  2757, which specify the optional evaporative emission standards will 
apply only through MY 2023  for consistency with Proposed Amendments to other 
sections.  As described in the purpose and rationale for § 2754(a)  in section  B of this 
chapter, the Proposed Amendments set the evaporative emission standards for all 
SORE except generator engines to zero for MY 2024 and subsequent model years, and set more stringent emission standards for generator engines. The Proposed 
Amendments set the evaporative emission standards for generator engines to zero for 
MY 2028 and subsequent model years. The proposed changes to this section of CP -
902 and to Title 13, CCR, §  2757 are necessary to implement the newly proposed 
emission standards and test procedures for MY  2024 and subsequent model years, 
while at the same time continuing to allow flexibility for earlier model years, and are  
293 necessary to provide consistency with the Proposed Amendments to § 2753(c). Under 
the Proposed Amendments to § 2753(c) and (d), beginning with MY  2024, all 
evaporative families must be tested in accordance with TP -902 for certification. In 
addition, the optional evaporative emission standards will no longer be more stringent 
than the evaporative emission standards once the emission standards of zero becom e 
effective. These changes obviate the need to certify any SORE to the optional 
evaporative emission standards beginning in MY  2024.  
§ 5. General Instructions – Evaporative Emission Control System Certification  
§ 5.1. Where to  Submit Applications for Certi fication  
Purpose. The Proposed Amendments change the “ Emissions Compliance, Automotive 
Regulations and Science Division” to the “ Emissions Certification and Compliance 
Division ” because of reorganization of divisions within CARB.  In addition, the 
Proposed Amendments change “9528 Telstar Avenue, El Monte, California 91731” to 
“4001 Iowa Street, Riverside, CA 92507” to reflect the address of CARB’s new 
Southern California headquarters.  
Rationale . These change s are necessary because CARB  divisions have been 
reorganized and renamed,  and construction of the new Southern California 
headquarters has been completed. The Emissions Certification and Compliance 
Division n ow has  responsibility for reviewing certification applications, so the division 
name has been updated. Division staff and the vehicle emissions testing  laboratories 
will be housed at the new headquarters.  
§ 5.2. Letter of Intent  
Purpose. The Proposed Amendments add the text, “ , and amended [insert amended 
date] ” to the reference for “ California Exhaust Emission Standards and Test 
Procedures for New 2013 and Later Small Off -Road Engi nes; Engine- Testing 
Procedures (Part 1054).”  The Proposed Amendments include a placeholder for the 
amended date, “[insert amended date] ”, that will be updated to reflect the CARB 
adoption date of the Proposed Amendments to these procedures described in 
sections F and  G later in this chapter, and provided in their entirety in Appendices  F 
and G.  
Rationale . This change is necessary to ensure manufacturers follow the most 
up-to-date testing procedures for SORE. Adding the amendment date for the test 
procedures clarifies the versions of the test procedures that must be used. Most 
proposed updates to the test procedures would further harmonize CARB’s test procedures with federal Part 1054 test procedures and incorporate updates made to 
federal Part 1054 since CARB’s test procedures were adopted. Section F later in this 
chapter describes the purpose and rationale for the Proposed Amendments for Part 1054, and Appendix F provides the Proposed Amendments in their entirety. 
Combining letters of intent for exhaust and evaporative emission certification may be  
294 convenient for manufacturers. In order to enable manufacturers to continue combining 
their letters of intent, it is necessary to specify the amended exhaust test procedures 
in this section.  
§ 6. Application Format Instructions  
Purpose. The current regulations in § 6 specify the types of information required to be 
included in certification applications. The information items are identified in a bulleted list. The Proposed Amendments add  a new bulleted item, “List of equipment brands 
using engines from the evaporative family, if known.”  
Rationale . This change is necessary to enable CARB staff to identify the Executive 
Order of Certification  Holder of SORE equipment in California commerce . CARB use 
this information to  help verify that products sold in California use certified engines.  In 
addition, i nformation on the brands of equipment using engines from an evaporative 
family is often requested by CARB when conducting testing. Inclusion of equipment 
brands using engines from the evaporative family  in the certification application will 
streamline future data requests.  
§ 7. Documentation of Certification  
Purpose. The current regulations in § 7 specify the items required to be included in 
Executive Orders of Certification. The items are identified in a bulleted list. Some of 
the bullets end with a period and others do not. The Proposed Amendments remove all the periods from the bullets. 
Rationale . This change is necessary to provide consistency and improve readability.  
Attachment 1 . SORE Evaporative Family Classification Criteria  
Purpose. The Proposed Amendments define the acronym “HDPE” by adding the text, 
“High -density polyethylene. ”  
Rationale . This change is necessary to provide  clarity because the term was not 
defined in CP -902. 
F. California Exhaust Emission Standards and Test Procedures for New 2013 
and Later Small Off -Road Engines; Engine -Testing Procedures ( Part 1054) 
This section provides a summary, purpose, and rationale for the Proposed 
Amendments to the California Exhaust Emission Standards and Test Procedures for New 2013 and Later Small Off -Road Engines; Engine- Testing Procedures ( Part 1054  ), 
referred to herein as “Part  1054”. These standards and test procedures are 
incorporated by reference in Title  13, CCR, § 2403. Appendix  F of this Staff Report 
provides the full proposed regulatory language of these standards and test procedures  with Proposed Amendments shown in strikeout and underline formatting.   
295 Global Amendments throughout Part  1054  
“ARB” to “CARB” Acronym Change  
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before  “Air Resources Board ,” for consistency with recent CARB 
document style practices designed to improve clarity. 
Rationale . This change reflects the California Air Resources Board’s recent change to, 
and preferred use of, the acronym “ CARB” versus the prior acronym, “ARB,” and the 
entire agency title, “California Air Resources Board.”  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents acces sible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines.  
Grammar Change to “Owner’s Manual”  
Purpose. The Proposed Amendments change t he phrase  “owners manual” to 
“owner’s manual” by adding an apostrophe in §§  1054.115(c), 1054.120(e), 
1054.125(a)(2), 1054.125(d), 1054.125(h), and 1054.801.  
Rationale . This change is necessary to correct nonstandard grammar in the previously 
adopted text. T he term “owner’s manual,” with the possessive apostrophe, is the 
correct grammar for referencing the document . California Administrative Law (Title  1, 
CCR, § 16(a)(4) ) requires that California regulations be free of grammatica l errors, 
which may create confusion or ambiguity or undermine the perceived 
authoritativeness of the regulation text. It is essential to satisfying the purpose of this regulation and addressing the identified problem that there be no such real or 
perceive d ambiguity or error in language use in the regulatory text.  
Table of Contents Change  
Purpose. The Proposed Amendments adjust p age numbers to accommodate added or 
removed text throughout  Part 1054. Amendments to the Table of Contents reflect 
these changes.  
Rationale . Amending the page numbers is necessary for accuracy and to prevent 
confusion for the reader.  
“Reserved” Placeholder Added  
Purpose. The Proposed Amendments add the placeholder text “[Reserved ]” to the 
following sections : §§ 1054.1(b), 1054.15(a ), 1054.15(c), 1054 .101(c -e), 1054.120(d),  
296 1054.145(a -i), 1054.145(k -o), 1054.201(d), 1054.201(h), 1054.205 (c), 1054.205(w), 
1054.230(d), 1054.230(f), 1054.825(e)(1)(i -iii), 1054.825(e)(1)(v -vi), 1054.825(e)(1)(vi ii), 
1054.825(e)(2), 1054.825(e)( 4), and Appendix I . The Proposed Amendments delete the 
subsection text, “(l)  [Reserved]” under § 1054.145. The purpose of these changes is to 
prevent gaps in the numbering and lettering of provisions while ensuring that 
provisions within Part 1054 that are similar o r analogous to provisions within Title 40, 
Code of Federal Regulations, Part  1054 (“federal Part 1054” or “federal text”)  have 
the same numbering  and lettering.  
Rationale . These changes are necessary to maintain sequential section numbering and 
lettering in order to improve readability and prevent confusion for readers. The 
incorporation of  Part 1054 into the California Code of Regulations in 2012, and the 
Proposed  Amendments, include a number of changes to text in the federal Part 1054 
necessary to addres s California -specific emission standards, production- line testing 
requirements, credit- generation allowances, and other regulations that  support 
California’s unique air quality programs . Some of these changes involved the deletion 
of portions  of the federa l text  that contain  provisions that are  redundant with, or in 
conflict with, other California SORE regulations.  In some cases, the subsection was 
deleted but subsequent items at the same numbering level were retained . The 
resulting gaps in numbering of pro visions would make the regulation more difficult to 
follow. R enumbering those provisions adopted or retained to eliminate gaps would 
result in similar provisions within the federal and California regulations being referred 
to by different subsection or paragraph numbers. The insertion of the “[Reserved]” 
placeholder preserves the similar numbering while removing any gaps in sequential 
numbering of provisions. It is essential to satisfying the purpose of this regulation that 
it be understandable and accessible to all stakeholders, and that similar designation of 
similar provisions bet ween California and federal text be preserved to avoid confusion 
on the part of regulated parties.  
Improvements to References  to California Code of Regulations  
Purpose. The Proposed  Amendments make  the following changes to references to 
regulations:  
• Change t he abbreviation “CCR”  to spell out “Title 13, California Code of 
Regulations”  or “California Code of Regulations” in §§ 1054.1(a)(4), 1054. 120, 
1054.2 01, 1054.205(p)(1), and 1054.205(u) .  
• Add the phrase “California Code of Regulations” where p reviously implied 
between “Title 13” and a section number in §§ 1054. 5, 1054.601(c)(1)  and 
1054.660.  
• Add “Title  13” where previously implied before  “California Code of 
Regulations” and a section number in §§ 1054.1(a)(4), 1054.205(u), and 
1054.230.   
297 Rationale . These changes are necessary to better identify the body of regulations t o 
which these subsections refer, to satisfy the clarity requirements under  California 
Administrative Law (Title 1, CCR, § 16), and to better differentiate them from the 
federal regulations. “CCR” is used in some places within this part, “California Code of 
Regulations” in others, and “Title 13” without elaboration in others still. Although the existing references are sufficient to identify the regulations, the use of different forms 
of reference could confuse  parties subject to the regulation s, as it may create the 
impression that these are different reference s. It is essential to satisfying the purpose 
of the regulations and addressing the identified problem that they be understandable 
to the regulated parties, including where references are made to other regulation s, 
and that there is no real or perceived ambiguity in such references.  
“EPA” to “CARB” Term Chan ge, “Certificate of Conformity” to “Executive 
Order” Term Change, and I mprovements to References to Parts  1054 
and 1065  
Purpose. The Proposed  Amendments make  the following changes throughout  
Part 1054:  
• Change “ EPA” to “CARB”  in §§  1054.30 (d), 1054.205(z), 1054.250 (section 
title), and 1054.255 (section title) . 
• Remove the definition and abbreviation entries for “EPA” in §§ 1054.801 and 
1054.805.  
• Change “certificate of conformity” and “certificate” to “Executive Order” in 
§§ 1054. 10(c), 1054. 30(d), 1054. 107(b), 1054.201, 1054.225, 1054.250(b)(5), 
1054.2 55, and 1054.640.  
• Remove the definition entry for “certificate of conformity” in §  1054.801.  
• Change references to “40 CFR 1054” to refer to “this part 1054” in 
§§ 1054.20(c), 1054.255(a), 1054.255(b), 1054.255(c)(4)(i), 1054.255(c)(7), 
1054.2 55(d), and 1054.645 . 
• Add t he word “section” to the  reference to “1054.205(r)” in § 1054.115.  
• Change “Part 1065” in § 1054.15(b)  to “The “ California Exhaust Emission 
Standards and Test Procedures for New 2013 Small Off Road Engines; Engine-
Testing Procedures (Part 1065),”  adopted October 25, 2012, and amended 
[insert amended date].” The Proposed Amendments include a placeholder for the amended date, “[insert amended date]”, that will be updated to reflect the CARB adoption date of the Proposed Amendments to Part  1065, which are 
described in section G later in this chapter, and provided in their entirety in Appendix G.  
• Change references  to “Part 1065 of this chapter,” “40 CFR part 1065,” 
“40 CRF 1065,” and “40 CFR 1065” to refer to “Part 10 65” in §§ 1054.15(b), 
1054.115(a)(1)(i), 1054.115(c), 1054.125, 1054.140 (a), 1054.205(g), 
1054.205(p)(1), 1054.230(e), 1054.235, 1054.235(a), 1054.235(f), 1054.235(g),  
298 1054.250(b)(3)(iv), 1054.501(b), 1054.501(b )(1), 1054.501(b)(2), 1054.501(b)(3), 
1054.501(b)(3)(i), 1054.501(b)(3)(ii), 1054.501(b)(4), 1054.501(b)(7), 
1054.501(b)(8)(ii), 1054.501(b)(8)(iii), 1054.501(b)(10)(ii), 1054.501(c), 
1054.501(c)(1), 1054.501(d), 1054.505(a)(1)(i), 1054.505(a)(2), 1054.505(b), 1054.505(b)(1)(iii), 1054.505(b)(2), 1054.505(d)(2), 1054.505(d)(4), 1054.505(e), 1054.650(a), 1054.801, and 1054 Appendix II.  
Rationale . These cha nges are necessary to  improve clarity and regulatory certainty. 
In 2012, CARB modified the SORE regulat ions to adopt portions of U.S. EPA’s Title 40, 
Code of Federal Regulations, Parts 1054 and 1065 (“federal Part 1054 and Part  1065” 
or “federal text”), to improve alignment of the certification and testing requirements 
without any changes in the stringency of the emission standards and associated test procedures, and without any cost impacts. Certain sections, section titles, subsections, or paragraphs, which were adopted without making other changes, contain references 
to U.S. EPA  and certificate of conformity carried over from the origi nal federal text. 
U.S. EPA uses  the term “certificate of conformity,” shortened to “certificate .” CARB  
uses the term “Executive Order” to refer to the certification document for an engine 
family for sale or lease for use  in California. In the 2012 adoption this was dealt with by 
adding definition entr ies clarifying that the terms “EPA” and “certificate of 
conformity” or “certificate”  should be understood to refer to CARB and Executive 
Order, respectively, for the purposes of California’s Part 1054. However, as much of 
the document must be reviewed before one reaches these definition entr ies, a 
potential for confusion still exists. This  proposed amendment ensures that the 
intended meaning of these references is immediately clear  to regulated parties and 
other stakeholders. Changing “EPA” to “CARB” and removing the definition for U.S. EPA are necessary to provide consistency with the incorporation of federal 
regulations into California’s SORE regulations and to  clarify that the Ca lifornia Air 
Resources Board is the agency having jurisdiction and decision- making authority under 
these regulation s and is the agency to which reports must be submitted.  It is essential 
to satisfying the purpose of the regulations and addressing the ident ified problem that 
there be no real or perceived ambiguity regarding the fact that the California Air Resources Board is the agency having jurisdiction and decision- making authority under 
this part, and the agency to which reports must be submitted.  Changi ng “certificate of 
conformity” and “certificate” to “Executive Order” and removing the definition for 
“certificate of conformity” would provide consistent use of California -specific 
terminology throughout the regulations, which better distinguishes them fr om the 
federal regulations and prevents confusion for manufacturers and other readers. These 
Proposed Amendments do not change any of the standards and test procedures.  
In addition, t he current regulations in California’s Part 1054 refer to the f ederal 
Part 1054 and Part 1065 in some places, and to Part 1054 and Part 1065 as adopted 
by CARB  in others, due to text carried over from the federal regulations during the 
2012 adoption process . This may create  confusion and the potential for apparently 
conflicting instructions , where differences between California’s Part 1054 and Part 
1065, and the federal  Part 1054 and Part 1065 exist . There is an additional potential  
299 for conflict if the federal  Part 1054 or Part 1065 is revised subsequent to the adoption 
of its text by CARB . The Proposed Amendments clarify that the referenced test 
procedures and other requirements are those specified in  California’s  Part 1054 and 
Part 1065, rather than the same- numbered paragraphs in the similar f ederal 
procedures.  The test procedures and other requirements in California’s Part 1054 and 
Part 1065 are the ones that properly apply to testing to address California 
requirements. Providing explicit references  to the California SORE  regulations in all 
places where the test procedures and other requirements contained therein are 
referenced prevents  ambiguity and potential conflict. It is essential to satisfying the 
purpose of the regulations and addressing the identified problem that the test 
procedures and other requirements referenced  here be consistent and understandable 
to the regulated parties, including where references are made to other regulation, and 
that there is no real or perceived ambiguity or conflict in regulatory instructions to regulated parties.  
Furthermore, the change to “Part 1065” the first place it is specified is necessary to 
ensure the amended test procedures are used for certification and compliance testing once they become effective. The most up -to-date test procedures must be followed 
by all manufacturers of MY  2013 and subsequent model year engines to ensure SORE 
meet the emission standards. Adding the amendment dates for the test procedures clarifies the versions of the test procedures that must be used.  
“Family Emission Limit” to “Family Emission Level” Term Change  
Purpose. The Proposed Amendments change the term “family emission limit” to 
“family emission level” to provide consistency of term usage throughout the SORE 
regulations. The Proposed Amendments include this change in §§ 1054.230(b)(9), 
1054.801, and  1054.805.  
The Proposed  Amendments also change  the definition in § 1054.801 to direct the 
reader  to the California -specific regulations,  as indicated  by strikeout  and underline  
formatting  in the following: 
Family emission  limit  level (FEL)  has the meaning given in Title 13, California 
Code of Regulations, Section 2401.  means an emission level declared by the 
manufacturer that will be used in the ABT program. The family emission level 
will take the place of an otherwise applicable emission standard. The fami ly 
emission limit must be expressed to the same number of decimal places as the 
emission standard it replaces. The family emission limit serves as the emission 
standard for the engine family (exhaust) or emission family (evaporative) with 
respect to all re quired testing.  
Rationale. These proposed  changes are necessary  to prevent  confusion  for 
manufacturers  and other  readers  and do not affect  SORE  emission standards  nor 
testing  requirements.  The California SORE  regulations traditionally use the term  
“Family Emission Level”  while the federal  regulations for small  nonroad  spark -ignition  
300 engines use the term “Family Emission Limit.” The California and federal  definitions 
are virtually identical:  
• Per Title  13, California Code of Regulations, § 2401(a): “ “Family emission level” 
or “FEL” means an emission level that is declared by the manufacturer to serve 
for the averaging, banking, and trading program and in lieu of an emission standard for certification. The FEL serves as the engine family’s emission 
standard for emissions compliance efforts. If the manufacturer does not declare 
an FEL for an engine family, the applicable emissions standard must be treated as that engine family’s FEL for the purposes of any provision of this Article. ” 
• Per federal Part 1054.801: “ Family emission limit (FEL)  means an emission level 
declared by the manufacturer to serve in place of an otherwise applicable emission standard under the ABT program in subpart H of this part. The family emission limit must be expressed to the same number of decimal places as the 
emission standard it replaces. The family emission limit serves as the emission 
standard for the engine family (exhaust) or emission family (evaporative) with respect to all required testing. ” 
In addition,  California Part 1054 Subp art H already  references  California regulatio ns 
for ABT program requirements,  as follows:  
Subpart H – Averaging, Banking, and Trading for Certification  
§ 1054.701 General provisions.  
“Each manufacturer must comply with all provisions of the averaging, bank ing, 
and trading program outlined in Title 13, California Code of Regulations, 
Sections 2408- 2409, for each engine family participating in that program.”  
However, as much of the document must be reviewed before one reaches 
§§ 1054.701 and 1054.801, a poten tial for confusion still exists. The proposed changes 
to provide consistent use of the term “Family Emission Level” satisfy clarity 
requirements under  California regulations (Title  1, CCR, § 16(a)(4)).  
Updates to Harmonize with Amended Federal Text  
Purpose. Subsequent to CARB’s adoption of Part 1054 into the California Code of 
Regulations, U.S.  EPA has made a number of terminology changes and other 
amendments to the federal Part 1054. The Proposed Amendments  revise  portions of 
California’s Part 1054 to prov ide consistency with (i.e., “harmonize”) these recent 
changes made to the wording of corresponding provisions in the f ederal Part 1054. 
These proposed harmonization amendments reflect changes U.S.  EPA made to the  
301 federal regulations after November 8, 2010,kk up to and including U.S.  EPA’s final 
regulatory amendments, “Improvements for Heavy- Duty Engine and Vehicle Test 
Procedures, and Other Technical Amendments,” published in the Federal Register on 
June 29, 2021.ll  
There are two types of proposed harmonization amendments to California’s Part 1054: (1) Amendments that provide the exact same words and organizational changes as 
U.S. EPA’s recent amendments to the federal Part 1054; and (2) Amendments that 
provide U.S. EPA’s recent amendments with one or more mo difications to incorporate 
California- specific changes necessary to maintain the stringency of California emission 
standards, provide consistency with existing California SORE regulations or other 
Proposed Amendments described in this staff report, or prevent confusion. T he 
proposed harmonization  amendments that include one or more California -specific 
modifications each have their own separate purpose and rationale descriptions that, 
along with the purpose and rationale descriptions for other Proposed Amend ments to 
California’s Part 1054, follow the “Global Amendments” subsection of this section F in 
the order in which they occur in the regulations. The following list identifies the 
sections, subsections, and paragraphs of California’s Part 1054 with proposed harmonization amendments that provide the exact same words  and organizational 
changes  as U.S. EPA’s recent amendments to the federal Part  1054.  
• Divide §  1054.2 into subsections 1054.2(a) and 1054.2(b).  
• Add to §  1054.125(c) a provision that allows maintenance of low -use engines to 
be specified in terms of calendar month intervals as well as in terms of 
operating life, and an example clarifying that engines may not be designed to 
require special maintenance for specific types of expected operation.  
• In § 1054.130(b)(5), change the text “ Describe any limits on the range of 
applications needed to ensure that the engine remains in its certified configuration after installation. ” to “Describe how your certification is limited 
for any type of application. ” Add the text “in this subpart” as indicated by 
underline in the following: “Also, if your wintertime engines are not certified to the otherwise applicable HC+NO
x standards  in this subpart, tell equipment 
manufacturers that the engines must be installed in equipment that is used only in wintertime. ” 
                                            
kk CARB incorporated portions of the federal Part 1054 into the California Code of Regulations in 
October 2012. The California Part 1054 adopted in 2012 is  based on the federal text as of 
November  8, 2010.  
ll U.S. EPA. 2021. Improvements for Heavy -Duty Engine and Vehicle Test Procedures, and Other 
Technical Amendments (Final Rule). Federal Register , Vol. 86, No. 122 , June 29, 2021, 
pages  34,308-34,590 (to be codified at 40 CFR Parts 9, 59, 60, 85, 86, 88, 89, 90, 91, 92, 94, 1027, 
1033, 1036, 1037, 1039, 1042, 1043, 1045, 1048, 1051, 1054, 1060, 1065, 1066, 1068, and 1074).   
302 • In § 1054.145, add the text “interim” to the first sentence as indicated by 
underline in the following: “ The interim provisions in this section apply instead 
of other provisions in this part. This section describes how and when these 
interim provisions apply. ” 
• In § 1054.205(p)(1), change the text “Include test results from invalid tests and 
from any other tests” to  “Indicate whether there are test results from invalid 
tests and or from any other tests of the emission -data engine,” and add a 
provision indicating that the regulatory agency may require these additional 
tests to be reported.  
• In § 1054.225(b), change the text “send the Designated Compliance Officer the 
following information” to  “send the following relev ant information to the 
Designated Compliance Officer.”  
• In § 1054.225(b) (2), add the text “in this part” to the end of each of the two 
sentences in this subsection.  
• In § 1054.225(b), add a new subsection, “(4)  Include any other information 
needed to make y our application correct and complete.”  
• In § 1054.235, change the section title from “ What exhaust emission testing 
must I perform for my application for a certificate of conformity?” to “What 
testing requirements apply for certification?”  
• In § 1054.235(a),  add the text indicated in underline: “Select a configuration 
and set adjustable parameters in a way  that is most likely to exceed the 
HC + NO x standard  in subpart B of this part , using good  engineering 
judgment .” 
• In § 1054.235(b), change the text “…you may ask us to exclude fuel mixtures 
that you can show are not likely to occur in use” to  “…you may ask us to 
instead perform tests with both fuels separately if you can show that intermediate mixtures are not likely to occur in use.”  
• In § 1054.235(d)(1),  change the text as indicated in underline  and strikeout: 
“The emission family from the previous model year differs from the current 
emission family only with respect to model year, items identified in 
§ 1054.225(a),  or other characteristics unrelated to emissions. You may also ask 
to add a configuration subject to §1054.225.  We may waive this criterion for 
differences we determine not to be relevant. ” 
• In § 1054.235(d)(3), add “of this part” to the first sentence, as indicated by 
underline in the following: “The data show that the emission data engine would 
meet all the requirements of this part  that apply to the emission family covered 
by the application for certification.” D elete the provision: “For engines 
originally tested under the provisions of 40 CFR part 90, you may consider 
those test procedures to be equivalent to the procedures we specify in subpart F of this part.”   
303 • In § 1054.240(a), change the text “This includes all test points over the course 
of the durabili ty demonstration” to  “This paragraph (a) also applies for all test 
points for emission- data engines within the family used to establish 
deterioration factors.”  
• In § 1054.240(b), change the text “…test results showing a deteriorated 
emission level for any p ollutant that is above an applicable emission standard ” 
to “…test results showing an official emission result or  a deteriorated emission 
level for any pollutant  that is above an applicable emission standard  in subpart 
B of this part.”  
• In § 1054.240(b), change the text “This includes all test points over the course 
of the durability demonstration” to  “This paragraph (b) also applies for all test 
points for emission- data engines within the family used to establish 
deterioration factors.”  
• In § 1054.240(c), add  the text indicated in underline in the following: 
“Determine a deterioration factor to compare emission levels from the 
emission- data engine with the applicable emission standards in subpart B of this 
part.”  At the end of the paragraph, add the sentence: “In the case of dual fuel 
and flexible fuel engines, apply deterioration factors separately for each fuel type.”  
• In § 1054.240(d), change the text “Adjust the official emission results for each 
tested engine at the low -hour test point by multiplying the me asured emissions 
by the deterioration factor, then rounding the adjusted figure to the same 
number of decimal places as the emission standard” to  “Determine the official 
emission result for each pollutant to at least one more decimal place than the 
applica ble standard  in subpart B of this part . Apply the deterioration factor to 
the official emission result, as described in §1054.245(e), then round the 
adjusted figure to the same number of decimal places as the emission standard.”  
• In § 1054.250(b)(3)(iv), change the text “All your emission tests, including 
documentation on routine and standard tests, as specified” to  “All your 
emission tests (valid and invalid), including the date and purpose of each test and documentation of test parameters as specified ,” and delete the text “and 
the date and purpose of each test ” from the end of the paragraph.  
• In § 1054.255(e), after the current provision, “We may void your certificate if we 
find that you intentionally submitted false or incomplete information,” add the 
sentence, “This includes doing anything after submitting your application that 
causes the submitted information to be false or incomplete.”  
• In § 1054.501(b)(2), change the text “meeting the specifications described in 
40 CFR 1065.710” to  “specified” in the initial paragraph , delete the sentence 
“You may alternatively use gasoline blended with ethanol as follows:” at the 
end of the initial paragraph, and delete the numbered paragraphs  (i) 
through  (iv).  
304 • In § 1054.505(a)(1), delete the text “In each mode, operate the engine for at 
least 5 minutes, then sample emissions for at least 1 minute .” 
• In § 1054.505( b)(2), make the following changes:  
o Change the text  “Control engine speeds and torques during idle mode 
as specified in paragraph (c) of this section and during full-load operating 
mode s as specified in paragraph (d) of this section. For all other modes, 
control torque as needed to meet the cycle -validation criteria” to 
“Control engine speeds and torques during idle mode as specified in 
paragraph (c) of this secti on. Control engine speed during the full -load 
operating modes as specified in paragraph (d) of this section. For all 
other modes, control the engine speed to within 5 percent of the nominal speed specified in paragraph (d) of this section or let the installed governor (in the production configuration) control engine 
speed. For all modes except idle, control torque as needed to meet the 
cycle -validation criteria .”  
o Delete the text  “control the engine speed to within 5 percent of the 
nominal speed specified in paragraph (d) of this section or let the installed governor (in the production configuration) control engine speed .” 
o In § 1054.601, add a new subsection: “(d)  Subpart C of this part 
describes how to test and certify dual fuel and flexible fuel engi nes. 
Some multi fuel engines may not fit either of those defined terms. For such engines, we will determine whether it is most appropriate to treat 
them as single fuel engines, dual fuel engines, or flexible fuel engines 
based on the range of possible and expected fuel mixtures.”  
• § In 1054.801, make the following changes:  
o Add to the definition of “ Dual-fuel engine ” the text” (see §1054.601(d)). 
For purposes of this part, such an engine remains a dual -fuel engine even 
if it is designed for operation on three or more different fuels.”  
o In the definition of “Engine configuration, ” change the text  “differ only 
with respect to normal production variability” to “differ only with respect to normal production variability or factors unrelated to emissions . 
o Add to the definition of “Flexible -fuel engine”  the text  “(see 
§1054.601(d) .”  
o In the definition of “Nonmethane hydrocarbon (NMHC) ,” change the 
text “means the sum of all hydrocarbon species except methane. Refer 
to §1065.660 for NMHC determination” to  “has the meani ng given in 
Part 1065.1001. This generally means the difference between the emitted mass of total hydrocarbon and the emitted mass of methane.”   
305 o In the definition of “Placed into service, ” add the text  “Engines and 
equipment  do not qualify as being “placed into service” based on 
incidental use by a manufacturer or dealer .”  
o In the definition of “Total hydrocarbon (THC) ,” change the text  “means 
the combined mass of organic compounds measured by the specified 
procedure for measuring total hydrocarbon, expressed as a hydrocarbon with a hydrogen -to-carbon mass ratio of 1.85:1” to  “has the meaning 
given in Part 1065.1001. This generally means the combined mass of organic compounds measured by the specified procedure for measuring total hydrocarbon, expressed as an atomic hydrocarbon with an atomic 
hydrogen -to-carbon ratio of 1.85:1.”   
o In the definition of “Total hydrocarbon equivalent (THCE) ,” change the 
text “means the sum of the carbon mass contributions of 
non-oxygenated hydrocarbons, alcohols and aldehydes, or other organic 
compounds that are measured separately as contained in a gas sample, 
expressed as exhaust hydrocarbon from petroleum -fueled engines. The 
hydrogen -to-carbon ratio of the equivalent hydrocarbon is 1.85:1” to 
“has the meaning given in Part 1065.1001. This generally means the sum 
of the carbon mass contributions of non- oxygenated hydrocarbon, 
alcohols and aldehydes, or other organic compounds that are measured separately as contained in a gas sample, expressed as exhaust hydrocarbon from petroleum- fueled engines. The atomic 
hydrogen -to-carbon ratio of the equivalent hydrocarbon is 1.85:1.”  
Rationale. These changes are necessary to provide consistency with  comparable 
provisions in the federal regulations for small nonroad engines, as applicable. Wit hout 
such consistency , manufacturers could be required  to satisfy additional requirements 
and/or certify separate engine families in California at considerable extra cost without 
a corresponding increase in emission benefits. The proposed changes are ident ical to 
the changes in the equivalent sections, subsections, and paragraphs of the f ederal 
Part 1054 due to amendments adopted by U.S.  EPA since  the adoption of California’s 
Part 1054. The Proposed Amendments would result in a more efficient certification process for engine and equipment manufacturers, consistent with the rationale for CARB’s incorporation of the federal regulations into the California Code of Regulations in 2012. These proposed changes would align CCR requirements with 
federal requirements that manufacturers already must follow, as applicable.  
Changes to Provide Consistency with Proposed “Handheld” Definition 
Purpose. The Proposed  Amendments make  the following changes to four sections of 
California’s Part 1054 —§§ 1054.115(c) , 1054. 205(r) , 1054.505(a) , and 1054.801—to  
provide  consistency  with the newly  proposed  definition for “handheld”  in Title 13 CCR 
§ 2401(a):  
• Change the definition of “handheld” in § 1054.801 from “Handheld means 
equipment that contains an engine with a displacement of less than 80cc” to  
306 “Handheld  has the meaning given in Title 13, California Code of Regulations, 
Section  2401. ” 
• Change the text “engines with displacements ≤80 cc” in §  1054.115(c) , and the 
text “ engines with a displacement of less than or equal to eighty cub ic 
centimeters ” in §  1054.505(a) , to “handheld engines.”  
• Change the text “engines with displacements >80 cc” in §  1054.115(c),  the text 
“engines with a displ acement of greater than 80  cc” in §§ 1054.205(r),  and the 
text “engines with a displacement of grea ter than eighty cubic centimeters” in 
§ 1054.505(a)  to “nonhandheld engines.”  
The current regulations in § 1054.115(c) specify requirements for engines that need 
altitude adjustments and include the following:  “Engines must meet applicable 
emission standar ds for valid tests conducted under the ambient conditions specified in 
40 CRF <sic> 1065.520. Engines must meet applicable emission standards at all 
specified atmospheric pressures except: (i)  engines with displacements ≤80 cc for 
atmospheric pressures below 96.0 kPa; and, (ii) engines with displacements >80 cc 
may rely on an altitude kit for atmospheric pressures below 94.0 kPa if you meet the requirements specified in 1054.205(r). ” The proposed changes to § 1054.115(c) would 
establish that only handheld engines, and not other engines with displacement less 
than or equal to  80 cubic centimeters, are exempt from meeting the emission 
standards at lower  atmospheric pressure, as occurs at higher altitudes, and that 
nonhandheld  engines may rely on an altitude kit to meet the standard at reduced 
atmospheric pressure even if their  displacement is 80 cc or less.  
The current regulations in § 1054.205 describe the information a manufacturer must 
include in a certification application , and subsection 1054.205(r)  specifies: “ Describe 
how your engines with a displacement of greater than 80 cc engines comply with 
emission standards at varying atmospheric pressures. Include a description of altitude kits you designed to comply with the req uirements of §1054.115(c). ” The proposed 
change to § 1054.205(r) would establish that manufacturers of all nonhandheld 
engines, and not just those with a displacement greater than  80 cubic centimeters,  
would be required to describe how their engines comply with emission standards at 
varying atmospheric pressures. 
The current regulations in § 1054.505 (a) describe requirements for how to test engines 
under steady -state conditions , and specifies: “ For engines with a displacement of less 
than or equal to eighty  cubic centimeters you must perform tests with discrete -mode 
sampling. For engines with a displacement of greater than eighty cubic centimeters 
we allow you to perform tests with either discrete -mode or ramped -modal testing 
methods. ” The proposed change to  § 1054.505 (a) would allow  manufacturers of all 
nonhandheld engines, and not just those with a displacement greater than  80 cubic 
centimeters,  to perform tests with either discrete mode or ramped modal testing 
methods .  
307 In addition, the Proposed Amendments add a subsection to § 1054.205 that was not 
included at the time Part 1054 was adopted in the California Code of Regulations:  
“(s) If your engines  are subject  to any handheld  engine provisions  on the basis  
of meeting  the definition of “handheld”  in Title 13, California Code  of 
Regulations,  section  2401,  describe  your analysis  showing  that you meet  the 
applicable  criteria. ” 
The proposed addition of §  1054.205(s) would require manufacturers of such engines 
to include in their certification applications their analyse s showing that they meet the 
applicable criteria  of the proposed definition of handheld.  
Rationale . The proposed changes are necessary to provide consistency with the newly 
proposed definition for “handheld”  in Title 13  CCR §  2401(a) and to ensure no excess 
emissions result from improper implementation of the emission standards or credit 
programs. The definition of “handheld” is currently in § 1054.801. California’s current 
emission standards do not distinguish between handheld and nonhandheld  SORE 
equipment  but rather  are based on displacement category. The  emission standards 
and other  provisions  are generally less stringent for  engines with displacement less 
than or equal to 80 cc, some of which are used in handheld equipment. When CARB 
adopt ed Part  1054 into the California Code of Regulations in 2012, CARB did not 
incorporate the federal definition of “handheld” but instead defined handheld in § 1054.801 as “equipment that contains an engine with a displacement of 
less than 80 cc.”  
However, the emission reduction credit program specified by §  2408.1 currently 
contains requirements specific to handheld equipment. In addition, use of a definition that classifies all equipment that contains an engine with a displacement of less than 
80 cc as “handheld” does not account for the challenges specific to handheld 
equipment that are not relevant for nonhandheld equipment using engines with displacement ≤ 80  cc. The design of some engines with displacement less than or 
equal to 80  cc used in handheld eq uipment may not be conducive to adjustments for 
high altitude. However, staff expects adjustments for high altitude can be made for 
nonhandheld equipment, such as portable generators, that use engines with 
displacement less than or equal to 80 cc. Therefor e, the broader exemption in 
§ 1054.115(c) adopted in 2012 is not appropriate for nonhandheld engines within this 
size range, and could prevent the full realization of the expected emission reduction 
benefits from California’s SORE exhaust standards.  
The Proposed Amendments to Part  1054 to provide consistency with the proposed 
“handheld” definition  in § 2401 are not expected to result in cost impacts to 
manufacturers because the proposed definition and associated changes more closely 
align CCR requirements with federal requirements for handheld engines that 
manufacturers already must follow, and available information indicates nonhandheld engines with displacement ≤80 cc  are either preempt from California’s standards 
(i.e., only subject to federal standards ) or are equipment types such as generators that  
308 already have the ability to make use of an altitude kit. Similarly, the federal 
Part 1054.205(s) contains the following text, which is comparable to the text of the 
proposed §  1054.205(s): “ (s) If your engines are subject to handheld emission 
standards on the basis of meeting weight limitations described in the definition of 
“handheld” in §1054.801, describe your analysis showing that you meet the applicable weight -related restrictions. ” Consequently, no cost impacts are expected from the 
proposed addition of the new subsection 1054.205(s) requirements to the California 
SORE regulations.  
Preface  
Purpose. The current regulations include the following preface  text before  and after  
the table  of contents:  
Befo re the table  of contents : 
“Note:  This appendix  shows the entirety of regulatory amendments to the test 
procedures  titled  below,  which  were  approved  by the Air Resources 
Board  on December  16, 2011,  and refined  via subsequent  conforming  
modifications  authorized  under  Resolution 11-41. Incorporated  by 
reference  into these  test procedures  are portions  of Title 40 of the Code  
of Federal  Regulations  (CFR)  Part 1054 – Control  of Emissions from  New,  
Small  Nonroad  Spark -Ignition Engines  and Equipment,  including  
Subpart s A, B, C, D, E, F, G, H and I, as amended  November 8, 2010;  
and, the internally referenced  sections  of Title 40 CFR,  Parts  60, 80, 86, 
90, and 1065.  Sections  that have  been  included  in their entirety are set 
forth  with the section  number  and title. Califo rnia provisions  that replace  
specific federal  language  provisions  are denoted  by the words  “DELETE”  
for the federal  language  and “REPLACE  WITH”  or “ADD”  for the 
California language.  The notation  [ * * * * * ] or [ ... ] means that the 
remainder  of the CFR text for a specific  section  is not shown  in these  
procedures  but has been  incorporated  by reference,  with only the 
printed  text changed.  CFR sections that are not listed are not part of the 
test procedures.  If there  is any conflict between the provisions  of this 
document  and the California Health  and Safety  Code,  Division 26, or 
Title 13 of the California Code  of Regulations  (CCR),  the Health  and 
Safety  Code  and Title 13 apply.  
 This document  is all newly  adopted text.”  
After  the table  of contents : 
“The following provisions  of Part 1054,  Title 40, Code  of Federal  Regulations,  
as proposed  by the United  States  Environmental  Protection  Agency  on the date 
listed, are adopted and incorporated  herein by this reference for 2013 model  
year and later small  off road engines as the California Exhaust  Emission 
Standards  and Test Procedures  for New 2013  and Later Small  Off Road  
Engines,  except  as altered  or replaced  by the provisions  set forth  below. ”  
309 “SOURCE: 75 FR 59259, November 8, 2010, unless otherwise noted ” 
The Proposed  Amendments delete this preface  text and add the following updated 
text before  the table  of contents:  
“Note:  This document provides the entirety of the California Exhaust Emission 
Standards and Test Procedures for New 2013 and Later Small Off -Road 
Engines; Engine- Testing Procedures (Part 1054), as adopted by the 
California Air Resources Board (CARB) on December 16, 2011, with 
additional conforming modifications authorized under Resolution 11- 41 
on October  25, 2012, and amended on [insert amendment date]. These 
standards and test procedures are incorporated by reference in Title 13, 
California Code of Regulations, § 2403. The Part 1054 section numbers, 
titles, and text correspond to same -numbered sections in Title 40 of the 
Code of Federal Regulations (CFR) Part 1054 – Control of Emissions from 
New, Small Nonroad Spark -Ignition Engines and Equipment, with 
California- specific modifications as necessary to maintain the stringency 
of California emission standards and provide consistency with other Califor nia regulations. CFR sections that are not listed herein are not a 
part of this Part 1054. The 2011/2012 CARB  rulemaking incorporated by 
reference portions of Title 40 CFR Part 1054, including Subparts A through I, as amended November 8, 2010; for clarity,  the 2021 CARB 
rulemaking included the entirety of the language from those portions of Title 40 CFR Part 1054, including Subparts A through I, incorporated by 
reference in Part 1054 from the 2011/2012 CARB rulemaking into 
Part 1054. The 2011/2012 CARB rulemaking also incorporated by 
reference the internally referenced sections in Part  1054 to Title 40 CFR 
Part 90 as amended October 30, 2009, Title 40 CFR Part 1051 as 
amended April 30, 2010, Title 40 CFR Part 1060 as amended 
September  16, 2010, Title 40 CFR Part 1065 as amended 
November 8, 2010, and Title 40 CFR Part 1068 as amended 
April  30, 2010. The 2021 CARB rulemaking included those portions of 
Title 40 CFR Part  1054 Subparts A, B, C, and I, as amended between 
November 8, 2010, and June 29, 2021, in Part  1054. The 2021 CARB 
rulemaking incorporated by reference the internally referenced sections 
in Part 1054 to Title 40 CFR Part 1051 as amended June 29, 2021, and 
Part 1068 as amended June 29, 2021. The 2021 CARB rulemaking 
removed the references to 40 CFR Parts 90, 1054, 1060, and 1065, and 
those CFR Parts are no longer incorporated by reference in this Part 
1065. If there is any conflict between the provisions of this document and 
the California Health and Safety Code, Division 26, or Title 13 of the 
California Code of Regulations, the Health and Safety Code and Title 13 
apply. ”  
310 The Proposed Amendments include a placeholder for the amended date, “[insert 
amended date],” that will be updated to reflect the CARB adoption date of the 
Proposed Amendments to Par t 1054 . 
Rationale . An updated preface is necessary for accuracy and clarity because, once the 
Proposed Amendments are approved, California Part  1054 will no longer be 
comprised of “all newly adopted text.” Instead, California Part 1054 will include text adopted by the 2011/2012 rulemaking as amended by the current rulemaking. The 
Proposed Amendments also provide an updated date of publication for the federal 
Part 1054 that is the source material for the Proposed Amendments, and updates the list of other 40 CFR parts internally referenced by the amendments and their 
associated publication dates. Three CFR parts, CFR Parts 60, 80, and 86, were listed in 
the 2011/2012 preface but were not cited later in California Part 1054, and therefore need not be incorporated by reference. The updated publication dates are necessary to maintain CARB’s ability to independently implement or enforce its regulations 
should U.S. EPA make a change that does not support the stringency of California 
emission standards or is otherwis e not consistent with other California SORE 
regulations. Also, Title 1, California Code of Regulations, § 20(c)(3), generally prohibits 
the incorporation by reference of material into California regulations without a date of 
publication or issuance. The 2011/2012 preface text that explains why some federal 
Part 1054 text is not shown is now not necessary because, for clarity, the document  
now includes the entirety of the language from those portions of Title 40 CFR Part 1054 incorporated by reference in Part 1054 by the 2011/2012 rulemaking into 
Part 1054.  
Subpart A – Overview and Applicability  
§ 1054.2  
Purpose. The current regulations specify: “ For provisions related to certification with 
respect to evaporative emissions, this generally means the equipment manufacturer.” 
The Proposed Amendments add the following text to the end of the sentence: 
“(i.e., the Executive Order Holder, as defined in Title 13, California Code of 
Regulations, section  2752) .”  
Rationale . This change is necessary to clarify that the party who holds the Executive 
Order  of Certification  (the Executive Order Holder ) certifying a given evaporative 
family is the party ultimately responsible for that evaporative family’s compliance with 
these requirements, even if ano ther party is considered the equipment manuf acturer. 
Such clarification is needed because i t is common for manufacturers of commercially 
available equipment powered by SORE to purchase engines, fuel system components, assembled fuel systems, or parts for f uel systems and engines from other companies. 
The party who is the Executive Order Holder for a given evaporative emission control 
system  or component may not be the party responsible for the ultimate production 
and assembly of the piece of equipment into which it is incorporated . As the Executive 
Order Holder for an evaporative family, this party is “the equipment manufacturer” for  
311 compliance purposes, and is responsible for the evaporative emission control  system’s 
compliance with the applicable standards  and certification levels . The current 
regulations already contain  text that clarifies that engine manufacturers that assemble 
the engine’s complete fuel system  are considered to be the equipment manufacturer 
with respect to evaporative emissions , but other arrangements may exist. This 
amendment clearly identifies  the parties responsible for compliance and ensures that 
those parties understand their responsibilities under these regulations.  
§ 1054.10(f)  
Purpose. Subsection 1054.10 describes how Part  1054 is organized into different 
subparts and identifies the topics of each. The text of §  1054.10(f) states: “Subpart F 
of this part describes how to test your engines (including references to other parts of 
the Code of Federal Regulations.” The Proposed Amendments add clarifying text, as 
indicated by underline in the following sentence: “Subpart F of this part describes how to test your engines (including references to other parts of the California Code of 
Regulations and specific sections, which are incorporated by reference, of the  Code of 
Federal Regulations). ”  
Rationale . This change is necessary to clarify that references in thi s part are  to other 
parts of the California Code of Regulations, and that individual sections, not entire parts, of the Code of Federal Regulations are incorporated  by reference. T hese 
revisions describe  the scope of references in the subpart, particularly the  provisions 
that refer to California’s specific regulations . The similar provisions in the federal Part 
1054 refer to f edera l regulations .  
§ 1054.10(g)  
Purpose. The text of §  1054.10(g) states: “Subpart G of this part and 40 CFR part  1068  
describe requirements, prohibitions, and other provisions that apply to engine manufacturers, equipment manufacturers, owners, operators, rebuilders, and all others.” The Proposed Amendments add clarifying text, as indicated by strikeout and underline in the following sentence: “ Subpart G of this part and  40 CFR  sections of 
Title 40, Code of Federal Regulations part 1068  as amended October 25t h, 2016, 
which are incorporated by reference , describe requirements…”  
Rationale . These changes are necessary to clarify that only sections of Title 40, Code 
of Federal Regulat ions Part 1068, are incorporated by reference in Subpart G , and to 
specify the version of federal regulations bei ng referenced and incorporated.  Letting 
readers know that the entirety of the federal Part 1068 is not incorporated into the California Code of Regulations helps improve regulatory certainty by indicating that manufacturers  may need to follow other portions of federal Part 1068 in addition to 
the portions incorporated into the California Code of Regulations. Specifying the version, by amendment date, of the Part 1068 that is being incorporated  is necessary 
to prevent conflicts with California SORE regulations should U.S. EPA amend Part 1068 in the future.   
312 § 1054.15  
Purpose. Section  1054.15 has the title, “ Do any other CFR parts apply to me?” The 
Proposed Amendments remove “CFR” from the section title  to clarify that this section 
refers to California SORE regulations and  not federal regulations.   
Rationale . This change is necessary to improve clarity by correcting an oversight that 
occurred at the time the federal Part 1054 regulations were incorporated into the 
Califo rnia Code of Regulations. T he original federal regulation’s section title was 
accidently included in the California Part 1054 regulations at the time of their adoption in 2012. This change is necessary to prevent  confusion for reader regarding the topic 
of the section and does not affect the applicability of the section’s provisions . 
§ 1054.20(d)  
Purpose. Section  1054.20 provides an overview of the requirements that apply to 
SORE equipment. Subsection 1054.20(d) states: “ You must certify your equipment or 
fuel systems as described in Title 13, California Code of R egulations, Chapter 15, 
Article  1.” The Proposed Amendments change the text “equipment or fuel systems” 
to “evaporative emission control systems” to  provide clarity about the regulatory 
scope.   
Rationale . This change is necessary to improve clarity by correcting an oversight that 
occurred at the time the federal Part 1054 regulations were incorporated into the California Code of Regulations. The text “equipment or fuel systems”  should have 
been changed to “evaporative emission control systems”  in 2012 when the California 
Part 1054 regulations were adopted in order to accurately reflect the scope of Title 13, 
California Code of R egulations, Chapter 15, Article 1, which requires any engine 
introduced into California commerce to have a certified and labeled evaporative 
emission control system. This change is necessary to prevent confusion about the scope of the current regulations.  
Subpart B – Emission Standards and Related Requirements  
§ 1054.101(a)(1)  
Purpose. The current regulations in § 1054.101(a)(1)  specify the exhaust emission 
standards for SORE, special provisions for wintertime engines , and voluntary Blue Sky 
Series emission standards, as they were set forth in Title 13, California Code of 
Regulations, Chapter 9, Article 1 § 2403 at the time CARB incorporated Part 1054 into 
the California Code of Regulations. The Proposed Amendments replace the text and tables in § 1054.101(a)(1)  that describe the emission standards and associated 
provisions  with the sentence,  “Exhaust emission standards are specified in Title 13, 
California Code of Regulations, Chapter 9, Article  1,” so  that the exhaust emission 
standards are not duplicated in § 1054.101(a)(1) .   
313 Rationale . This change is necessary to prevent  the occurrence of conflicting 
regulations should, in the future, § 1054.101(a)(1)  not be amended at the same time 
§ 2403(b) is amended. Exhaust emissions from SORE  manufactured for sale, sold, 
offered for sale in California, or that are introduced, delivered or imported into 
California for introduction into commerce, must comply with the standards specified in Title 13, California Code of Regulations, §  2403. Duplicating  standards and other 
provisions already specified in  § 2403 creates unnecessary redunda ncy and complexity 
when amendments to § 2403 are needed , and adds to the length of § 1054.101(a)(1) . 
Specifying  a reference to , ”Title 13, California Code of Regulations, Chapter 9, 
Article  1” ensures that manufacturers and other stakeholders refer to the most recent 
version of applicable exhaust standards. 
§ 1054.107  
Purpose. The current regulations in § 1054.107 describe an engine family’s useful life, 
which is the period during which engines are required to comply with all emission standards that apply.  The Proposed Amendments delete text from the second 
sentence of the initial unnumbered paragraph that currently applies a five- year 
maximum limit to the useful life period, as indicated by strikeout in the following: “ The 
useful life period is f ive years or  a number of hours of operation,  whichever comes 
first, as described in this section. ” 
Rationale . These changes are necessary to provide consistency with current SORE 
exhaust emission regulations in §  2403(b)(1) that specify emissions durability periods,  
and the Proposed Amendments that would update the required period for MY  2024 
and subsequent model year engines. The current § 2403(b)(1) provisions allow 
applicants for certification to select a durability period for their engines from a range of choices  that generally reflect “moderate,” “intermediate,” or “extended,” use. As 
described in section A of this chapter, the Proposed Amendments for § 2403(b)(1) 
would lengthen the emissions durability periods for some engines to more accurately 
reflect the useful lifetime of SORE equipment, and would allow only one durability 
period option per displacement category: 300, 500, or 1,000 hours, depending on the 
displacement category.  Both the current regulations and the Proposed Amendments 
to § 2403(b)(1) define durability periods in terms of minimum number of hours of 
operation, without any maximum period limit in terms of hours or years.  
§ 1054.107(a)(1) and (2)  
Purpose. The current regulations in § 1054.107(a)(1)  specify  the useful  life periods  for 
meeting  exhaust  emission standards  by referencing  “Title 13, California Code  of 
Regulations,  Chapter  9, Article  1, Section  2404 .” The current regulations in § 2404 
specify  requirements  for engine or equipment  manufacturers  to affix a label  (or labels)  
on each  productio n engine (or equipment,  as applicable)  to provide : 
• The engine or equipment owner and service mechanic with information 
necessary for the proper maintenance of these parts in customer use; and   
314 • The potential consumer s with information regarding relative emissions levels.  
The current regulations in § 2404(l) specify requirements for the Air Index label 
content and locations. For engines certified to emission standards subject to an emissions durability period as set forth in § 2403(b) and for engines used  to meet the 
requirements of §2403(c), each engine manufacturer currently must make Air Index 
and durability period information available to potential consumers. Section  2404(l)(2) 
specifies that the emissions durability period must be indicated by the act ual hours, by 
the descriptive terms shown in the table provided in that section, or by both . The 
table has two sections, one for descriptive terms applicable to MYs  2000 through 
2004, and the second for descriptive terms applicable to MY  2005 and subsequent 
model years. The Proposed Amendments change model year applicability for the 
second table section from model year “2005 and subsequent,” to “2005 through 2023,” for consistency with other Proposed Amendments to § 2403. The change to 
the model year applic ability is necessary to provide consistency with the Proposed 
Amendments to emissions durability periods specified in § 2403(b)(1) for MY  2024 and 
subsequent model years. The proposed emissions durability periods are the same for all engines within a displacement class. Therefore, using a descriptive term on the 
emission control label to supplement the number of hours in the emissions durability 
period will no longer be necessary.  
To provide  consistency  with the Proposed  Amendments to §§ 2403  and 2404,  the 
Proposed  Amendments include two changes to § 1054.107(a) : 
• Add the text “ For model years 2013 through 2023, ” to the beginning of 
§ 1054.107(a)(1) to specify that its provisions apply to MYs  2013 through 2022.  
• Add a new paragraph 1054.107(a)(2)  to specify that for MY  2024 and 
subsequent model years, the useful life period for exhaust requirements is 
specified in the table in Title 13, California Code of Regulations, § 2403(b)(1).  
Rationale . These changes are necessary because the P roposed Amendments would 
modify § 2403 such that § 2403(b)(1) specifies new useful life periods (i.e., emissions 
durability periods) for MY 2024 and subsequent model years. The new ly proposed  
subsection 1054.107(a)(2) is necessary to ensure that regulated parties consulting 
Part 1054 are aware of these provisions as amended for MY 2024 and subsequent 
model years and know where to find them . 
§ 1054.107(a)(3) [newly proposed paragraph]  
Purpose. The Proposed Amendments add a new paragraph 1054.107(a)(3) that 
specifies:  
“You may select  a longer  useful  life than that specified in paragraph  (a)(1) 
or (a)(2) of this section  as applicable  in 100-hour increments  not to exceed  
3,000 hours for Class  I, III, IV, and V engines , or 5,000  hours for Class  II engines.  
Engine classes  are defined  in Title 13, California Code  of Regulations,   
315 section  2403.  For engine families generating  emission credits,  you may do this 
only with our approval. ” 
In this proposed text, “you” means the certifying manufacturers, consistent with the 
definition in § 1054.2, and “our” means CARB, consistent with the definition in 
§ 1054.801. As currently defined by §  2403(b)(1), SORE engine classes have the 
following displacement ranges: Class I:  65 cc to <  225 cc; Class II:  ≥ 225 cc; 
Class  III: < 20 cc; Class  IV: 20 cc to <  50 cc; and Class V: ≥ 50 cc to 65  cc. 
Rationale . This change is necessary to allow  manufacturers the flexibility to specify a 
longer useful life period for one or more engine families, while providing CARB discretion to confirm that longer useful lives specified for emission credit- generating 
engine families are appropriate. The federal  Part 1054 contains a similar provision, but 
it was not adopted into the California Code of Regulations by California in 2012 . This 
provision is intended to allow manufacturers fl exibility in design and marketing of 
SORE equipment, particularly handheld equipment, and encourage manufacturers to 
design and market more durable, higher -quality products, that reduc e lifetime 
emissions . At the same time, requiring CARB’s approval for specification of longer 
useful life periods for families that generate emission credits would ensure that 
manufacturers do not claim unrealistically or inappropriately long useful life periods in 
order to maximize credit generation without actually realizing  the expected emission 
benefits. Providing this flexibility, subject to specific oversight in the case of emission 
credit generating families, reduces the burden on manufacturers and facilitates 
compliance while preserving the intended emission reduction benefits of the emission 
standards and emission reduction credit programs.  
The “not to exceed” values of 3,000 hours for Class I, III, IV, and V engines, and  5,000 
hours for Class II engines,  are equivalent to those specified for Class I and II engines, 
respectively, by U.S. EPA in the federal Part 1054.  
§ 1054.115(b)  
Purpose. The current regulations in § 1054.115 identify additional  requirements that 
apply  to engines  that are required  to meet  the emission standards . 
Section  1054.115(b)  specifies requirements  for engines with adjustable  parameters  
and includes the following: 
“Engines that have  adjustable  parameters  must  meet  all the requirements of 
this part for any adjustment  in the physically adjustable  range.  An operating  
parameter is not considered  adjustable  if you permanently seal it or if it is not 
normally accessible using  ordinary tools.  …” 
To provide clarification, the Proposed Amendments delete the text “or if it is not normally accessible using ordinary tools ” and add a new sentence, “ Operating 
parameters that can be adjusted using tools are considered adjustable. ”   
316 Rationale . This change is necessary to remedy unintentional vagueness and confusion 
caused by the current text “normally accessible using ordinary tools.” Providing 
clarification is necessary to maintain the stringency of California ’s emission standards 
and to achieve  the expected emission benefits of the current regulations. In the 
present market environment, even specialized tools can be readily obtained by SORE 
equipment  owners to adjust parameters such as high- and low-speed fuel mixtures. 
Owners may adjust parameters to achieve  performance benefits or for personal 
preference . Therefore,  in practice , SORE may operate with any parameter set to any 
value that can be achieved  with the use of tools, and  such settings must be reflected in 
the range of operating parameter settings used during engine emissions testing 
conducted under this part .  
§ 1054.125  
Purpose. The current regulations in § 1054.125 specify requirements for maint enance 
instructions that manufacturers must give to the consumer (i.e., “ultimate purchaser”) of each new engine and include the following text in the initial unnumbered paragraph: “ The maintenance instructions also apply to service accumulation on your 
emission- data engines as described in §1054.245 and in 40 CFR part 1065. Note that 
for engines with a displacement of less than or equal to 80 cc you may perform 
maintenance on emission- data engines during service accumulation provided that 
exhaust emission tests are performed before and after the maintenance is performed. ”  
As described in the “Global Amendments” section, the Proposed Amendments 
change “40 CFR part 1065” to “Part 1065” in the first sentence. In addition, the 
Proposed Amendments delete the second sentence, “ Note that for engines with a 
displacement of less than or equal to 80 cc you may perform maintenance on 
emission- data engines during service accumulation provided that exhaust emission 
tests are performed before and after the maintenance is performed. ” 
Rationale . The first change is necessary to improve clarity by correcting an oversight 
that occurred at the time certain  federal regulations were incorporated into the 
California Code of Regulations. Changing “40 CFR part 1065 ” to “Part 1065 ” clarifies 
that the referenced test procedures and other requirements are those specified in  
California’s Part 1065, rather than the similar federal procedures.  See the Global 
Amendments subsection, “ “EPA” to “CARB” Term  Change, “Certificate of 
Conformity ” to “Executive Order” Term Change,  and Improvements to References to 
Parts 1054 and 1065,” in this section F for additional explanation.  
The second change, to delete the sentence, “Note that for engines with …,” is 
necessary to harmonize California’s Part  1054 with recent amendments to the federal 
Part 1054. In an amendment published at 86  FR 34517, June 29, 2021, the U.S.  EPA 
deleted the equivalent sentence from the federal Part  1054.125, “ Note that for 
handheld engines subject to Phase 3 standards you ma y perform maintenance on 
emission- data engines during service accumulation as described in 40 CFR part 90. ”   
317 § 1054.125(a)(1)  
Purpose. The current regulations in § 1054.125(a) define what is meant by “critical 
emission- related maintenance” and specify the conditions that must be met for a 
manufacturer to be allowed to schedule maintenance on critical emission- related 
components. Section 1054.125(a)(1) specifies the following condition:  
“You demonstrate  that the maintenance  is reasonably  likely to be done  at the 
recommended  intervals  on in-use engines.  We will accept scheduled  
maintenance as reasonably  likely to occur if you satisfy  any of the following 
conditions:  
(i) You present  data showing  that any lack of maintenance that increases 
emissions  also unaccep tably degrades  the engine's performance.  
(ii) You present  survey  data showing  that at least  80 percent of engines in the 
field get the maintenance you specify  at the recommended  intervals.  If the 
survey  data show  that 60 to 80 percent  of engines in the field get the 
maintenance you specify  at the recommended  intervals,  you may ask us to 
consider  additional  factors  such as the effect  on performance  and emissions.  
For example, we may allow you to schedule fuel injector replacement  as critical  
emission related  maintenance  if you have  survey  data showing  this is done  at 
the recommended  interval  for 65 percent  of engines and you demonstrate  that 
performance  degradation  is roughly  proportional  to the degradation  in 
emission control  for engines  that do not have  their fuel injectors  replaced.  
(iii) You provide  the maintenance free of charge  and clearly say so in your 
maintenance instructions.  
(iv) You otherwise show  us that the maintenance is reasonably  likely to be done  
at the recommended  intervals .” 
The Proposed Amendments change “We will” to “We may” in the second sentence of 
§ 1054.125(a)(1) to enable CARB to have discretion in accepting that scheduled 
maintenance is reasonably likely to occur.  
Rationale . This change is necessary to balance the flexibility that the §  1054.125(a)(1) 
conditions currently allow for certifying manufacturers to demonstrate that maintenance is reasonably likely to be done at the recommended intervals on in- use 
engines. CARB must have the discretion to disagree with a manu facturer’s definition 
of “reasonably likely” when CARB assesses whether data provided in the manufacturer’s demonstration adequately represent r eal-world SORE maintenance 
practices in order to ensure emission data produced by the test procedures are 
repres entative of real -world emissions. This representativeness is necessary to ensure 
that engines determined to be in compliance with Part  1054 are indeed compliant and 
do not result in excess emissions.    
318 § 1054.125(f)  
Purpose. The current regulations in § 1054.125(f) specify requirements for 
maintenance instructions regarding the source of parts or repairs, and specify 
conditions for when a manufacturer is allowed to disregard the requirements. The 
Proposed Amendments add clarifying text, as indicated in the following in underline and strikeout text:  
“You may disregard  the requirements  in this paragraph  (f) for a component  or 
service  if you do one of two things:  
(1) Provide  a the component  or service  without  charge  under  the purchase 
agreement.  
(2) Get us to waive  this prohibition in the public's interest  by convincing  us the 
engine  will work  properly only with the identified component  or service. ” 
Rationale . This change is necessary to improve clarity and consistency within the text 
of this section, which eliminates ambiguity and improves readability for manufacturers. 
The first proposed change § 1054.125(f), addition of the text “ for a component or 
service ,” provides consistency with the wording of § 1054.125(f)(1), which already 
specifies that the conditions apply to  “component or service .” The second proposed 
change, changing “a” to “the,” corrects the grammar for consistency with the first proposed change.  These Proposed Amendments do not make a substantive change to 
any of the current standards and test  procedures.  
§ 1054.130(b)(4)  
Purpose. The Proposed Amendments add “the” to the text in the current regulations, 
“in accordance with t he Executive Order” to correct a grammatical error inadvertently 
included in 2012 when the federal regulations were adopted into the California Code 
of Regulations.  
Rationale . This change is necessary to correct a grammatical mistake and does not 
make a substantive change to any of the current standards and test procedures.  
California Administrative Law (Title  1, CCR, § 16(a) (4)) requires that California 
regulations be free of grammatical errors, which may create confusion or ambiguity or 
undermine the perceived authoritativeness of the regulation text. It is essential to satisfying the purpose of this regulation and addressing the identified problem that 
there be no such real or perceived ambiguity or error in language use in the regulatory 
text.  
319 Subpart C – Certifying Emission Families  
§ 1054.205(t)  
Purpose. The current regulations in § 1054.205 describe the information a 
manufacturer must include in a certification application, and subsection 1054.205( t) 
specifies:  
“(t) State  whether  your certification  is limited for certain  engines.  If this is the 
case,  describe  how you will prevent  use of these engines in applications for 
which  they are not certified.  This applies  for engines such as the following:  
(1) Wintertime  engines  not certified  to the specified  HC+NO x standard.  
(2) Two- stroke  snowthrower  engines using  the provisions  of § 1054.101(d).”  
The Proposed Amendments delete t he entirety of §  1054.205(t)(2)  and revise the 
remaining text to remove the list format, so that the final sentence of the subsection 
would be: “This applies for engines such as wintertime engines not certified to the 
specified HC+NO X standard.”  
Rationale. This change is necessary to prevent confusion for the reader by correcting 
an oversight that occurred at the time the federal Part 1054 regulations were 
incorporated into the California Code of Regulations.  The current text in 
§ 1054.205(t)(2) refers to “ § 1054.101(d).” However, CARB did not adopt 40 CFR 
§ 1054.101(d) into the California Code of Regulations in 2012, and there is no Title 13 
CCR § 1054.101(d).  
§ 1054.205(v)  
Purpose. The current regulations in § 1054.205(v)  require  manufacturers  to include 
good -faith estimates  of California- directed  production  volumes  in their certification  
applications, consistent  with federal  regulations prior  to June 2021,  as specified  by the 
following: 
“(v) Include good -faith estimates  of California -directed  production  volumes.  
Include a justification  for the estimated  production  volumes  if they are 
substantially  different  than actual  production  volumes  in earlier years  for similar 
models.  Also indicate  whether  you expect  the engine family to contain  only 
off-road engines,  only stationary engines,  or both. ” 
Changes made  in U.S. EPA’s  final regulatory amendments,  “Improvements  for Heavy-
Duty Engine and Vehicle Test Procedures,  and Other  Technical  Amendments,”  
published  in the Federal  Register  on June  29, 2021, include additional  requirements,  
as indicated  by strikeout  and underline  in the following text for 40 CFR 
Part 1054.205(v):   
320 “(v) Provide the following information about your plans for producing and selling 
engines:  
(1) Identify the estimated initial and final dates fo r producing engines from the 
engine family for the model year.  
(2) Identify the estimated date for initially introducing certified engines into 
U.S. commerce under this certificate.  
(3) Include good -faith estimates of U.S. -directed production volumes. Include a 
justification for the estimated production volumes if they are substantially 
different than actual production volumes in earlier years for similar models. Also indicate whether you expect the engine family to contain only nonroad 
engines, only stati onary engines, or both.”  
The Proposed  Amendments would  incorporate  the above  underlined  changes into 
California Part 1052.205(v)  to harmonize  the California Code  of Regulations  with the 
recent  federal  regulation  changes,  with two modifications  to make  the changes 
specific to California: 
• In § 1054.205(v)(2), change the federal version of the text “ into U.S. commerce 
under this certificate ” to “ into commerce in California under this Executive 
Order .” 
• In § 1054.205(v)(2), add the sentence “ If your estimates ar e based on 
U.S.-directed p roduction volumes, include U.S. -directed production volumes 
and information or analysis that provides the basis for determini ng your 
estimates of California -directed production volumes. ”  
Rationale . These changes are necessary to provide consistency with (i.e., “harmonize”) 
recent changes made to the corresponding provisions in the federal Part 1054 . The 
proposed changes to incorporate the new federal requirements would not result in 
cost impacts to manufacturers because they align  CCR requirements with federal 
requirements that manufacturers already must follow. The proposed California -specific 
requirement to provide addition information for California -directed production 
volumes  based on U.S. -directed production volumes  is necessa ry for CARB to assess 
the accuracy of projected California sales volume s reported by manufacturers . An 
accurate accounting of projected sales volumes is necessary to ensure no excess emissions result from implementation of the current and proposed credit p rograms 
under Title 13 CCR §§ 2408 through 2408.2, § 2754.1, and § 2754.3. This California -
specific requirement is not expected to have any cost impact for manufacturers because manufacturers would not be required to create new information. The requirement  is merely to provide their existing information or analysis to CARB.  
§ 1054.205(z)  
Purpose. The Proposed  Amendments make  corrections  as indicated  by strikeout  and 
underline in the following:  
321 “Name  an agent  for service  located  in the United  States.  Service  on this agent  
constitutes  service  on you or any of your officers  or employees for any action  by 
EPA CARB  or otherwise by the United  States  State  of California related  to the 
requirements  of this part. ” 
Rationale : These changes are necessary to prevent confusion for the reader by 
correcting an oversight that occurred at the time the federal Part 1054 regulations 
were incorporated into the California Code of Regulations, and to improve clarity and 
regulatory certainty.  
§ 1054.205(aa)  
Purpose.  The Proposed  Amendments make  corrections  as indicated  by strikeout  and 
underline in the following: 
“(aa) For imported  engines or equipment,  identify the following: 
(1) The port(s)  at which  you have  imported  your engines (or equipment  
containing  your engines)  over the previous  12 months.  
(2) The names  and addresses of the agents  you have  authorized  to import your 
engines or equipment.  
(3) The location  of a test facility in the United  States  where you can test your 
engines if we select  them  for compliance  testing  under  a selective  enforcement  
audit,  as specified  in 40 CFR part 1068,  subpart  E Title 13, California  Code  of 
Regulations,  § 2407 .”  
Rationale . This change is necessary to prevent confusion for the reader by correcting 
an oversight that occurred at the time the federal regulations were incorporated into 
the California Code of Regulations in 2012.  Federal regulations use the term “selective 
enforcement audit” to refer to provisions substantially similar to the provisions that 
California SORE regulations describe as “compliance testing ” for in-use test ing and 
validation of engines in § 2407, “New Engine Compliance and Production Line Testing 
– New Small Off Road Engine Selection, Evaluation, and Enforcement Action.”  
However, referencing the federal  regulat ions here, rather than the applicable 
California regulatory provisions , could create regulatory conflicts and confusion. The 
proposed change to reference § 2407 instead of 40 CFR part  1068 would not result in 
cost impacts to manufacturers because manufacturers alrea dy must follow applicable 
CCR § 2407 requirements and applicable 40  CFR part  1068 requirements.  
§ 1054.220(b)  
Purpose. The current regulations in § 1054.220 specify how a manufacturer may 
amend its emission- related maintenance instructions after submitting  a certification 
application. The Proposed Amendments change the text “anytime” to “at any time” in the current text of §  1054.220(b): “… you may distribute the new maintenance 
instructions anytime after you send your request .”   
322 Rationale . This change is n ecessary to correct a grammatical error in the federal 
regulations that CARB inadvertently incorporated into the California Code of 
Regulations in 2012. The change improves readability and is not a substantive change. 
California Administrative Law (Title  1, CCR, § 16(a)(4) ) requires that California 
regulations be free of grammatical errors, which may create confusion or ambiguity or undermine the perceived authoritativeness of the regulation text. It is essential to 
satisfying the purpose of this regulation and addressing the identified problem that 
there be no such real or perceived ambiguity or error in language use in the regulatory 
text. 
§ 1054.225(e)  
Purpose. The current regulations in § 1054.225 specify how a manufacturer may 
amend a certification application to include new or modified engines or fuel systems 
or change an FEL . The Proposed Amendments change the text “anytime” to “at any 
time” in the current text of § 1054.225(e) : “… may start producing the new or 
modified configuration anytime after you send us your amended application. ”  
Rationale . This change is necessary to correct a grammatical error in the federal 
regulations that CARB incorporated into the California Code of Regulations in 2012. The change improves readability and is not a substantive change.  California 
Administrative Law (Title  1, CCR, § 16(a)(4) ) requires that California regulations be free 
of grammatical errors, which may create confusion or ambiguity or undermine the perceived authoritativeness of the regulation text. It is essential to satisfying the purpose of this regulation and addressing the identified problem that there be no such real or perceived ambiguity or error in language use in the regulatory text.  
§ 1054.230(b)  
Purpose. The current regulations in § 1504.230 pro vide instructions to manufacturers 
for how to divide their product line into different engine families. Subsection (b) 
specifies the conditions for grouping engines into the same emission family for exhaust emissions, and subsection (b)(7) specifies the co ndition: “ (7) Engine class, as 
defined in §  1054.801 .” The Proposed Amendments change the text “§ 1054.801” to 
“Title 13, California Code of Regulations, § 2403. ” 
Rationale . This change is necessary to prevent confusion for the reader by correcting 
an over sight that occurred at the time CARB incorporated certain sections of federal 
Part 1054 into the California Code of Regulations in 2012. CARB incorporated the text 
of § 1504.230(b)(7) as written in the federal Part 1054 but did not incorporate the 
federal Part 1054.801 engine class definition. The California SORE regulations define 
engine class in § 2403(b).   
323 § 1054.230(d)  
Purpose. The current regulations in § 1054.230(d)  specify:  
“You  may group  engines that are not identical with respect  to the things listed  
in paragraph  (b) of this section  into the same  emission family,  as follows:  
(3) The provisions  of this paragraph  (d) do not exempt  any engines from  
meeting  all the applicable  standards  and requirements  in subpart  B of this 
part.”  
The Proposed Amendments delete the text of § 1054.230(d), and add the text 
“[Reserved] .”  
Rationale . This change is necessary to correct an oversight that occurred at the time 
CARB incorporated the federal regulations into the California Code of Regulations in 
2012. As noted  in Appendix H of the 2011 ISOR,mm CARB did not incorporate 
40 CFR §1054.230(d)(1) and (d)(2) into the California Code of Regulations. The 
remaining text in Title  13 CCR  § 1054.230(d)( 3) is meaningless without any preceding 
provisions. Consequently, the Proposed Amendments remove the text to prevent confusion for the reader, and add the text “[Reserved]” to maintain the sequential lettering of the provisions in § 1054.230 and ensure that provisions analog ous to 
provisions within f ederal Part 1054 have the same lettering.  
§ 1054.230(f)  
Purpose. The current regulations in § 1054.230(f)  specify:  
“You may combine  engines from  different  classes into a single emission family 
under  paragraph  (d)(1)  of this section  if you certify the emission family to the 
more  stringent  set of standards  from  the two classes in that model  year. ” 
The Proposed Amendments delete the text of § 1054.230(f), and add the text 
“[Reserved] .” 
Rationale . This change is necessary to correct an oversight that occurred at the time 
CARB incorporated the federal regulations into the California Code of Regulations in 2012. As noted in Appendix H of the 2011 ISOR (CARB, 2011b), CARB did not incorporate 40  CFR §1054.230(d)(1). As a result, the provision in § 1054.230(f) is 
meaningless because it refers to a subsection that does not exist in the California 
                                            
mm CARB. 2011. Staff Report: Initial Statement of Reasons for Proposed Rulemaking - Adoption of The 
Proposed Amendments to California’s Smal l Off-Road Engine and Tier 4 Off- Road Compression -Ignition  
Engine Regulations and Test Procedures; and, Amendments to The Exhaust Emission Certification Test 
Fuel for Off- Road Spark -Ignition Engines, Equipment, and Vehicles. Report prepared by staff of the 
Emission Research and Regulatory Development Branch, Mobile Source Control Division, CARB. October 2011.   
324 Code of Regulations. Consequently, the Proposed Amendments remove the text to 
prevent confusion for the reader, and add the text “ [Reserved]” to maintain the 
sequential lettering of the provisions in § 1054.230 and ensure  that provisions 
analog ous to provisions within federal Part 1054 have the same lettering.   
§§ 1054.245(a), (b), (c), (e)(1) and (e)(2)  
Purpose. Section  1054.245 specifies the different ways a manufacturer can determine 
deterioration factors (DF). A  deterioration factor is the calculated or assigned number 
that represents the certification engine’s emissions change over the emissions durability period. Subsection 1054.245(a) specifies that manufacturers may, at their 
option, use DFs from Tables 1 or 2, which are in §§ 1054.245(b) and 1054.245(c), 
respectively, or calculate DFs according to the process described in  § 1054.245(d), or, 
for technologies that are not addressed in Table 1 or Table 2, the manufacturer may 
ask the Executive Officer to assign a DF  prior to the time of certification . 
Subsections  1054.245(a) through (c) are intended to give small -volume engine 
manufacturers a lower cost option for determining deterioration factors  (CARB, 2011).  
Section  1054.245(d) specifies the f ormula for calculating DFs  for engines with 
aftertreatment, and §  2054.245(e) specifies additional provisions for the determination 
of DFs.  
The Proposed  Amendments include seven  types  of nonsubstantive changes  to 
improve  clarity not already  described  in the “Global  Amendments”  section:  
• First, in § 1054.245(a), change the text “Table 1 or Table 2 of this paragraph 
(a)” to “Table 1 or Table 2 of this section.”  
• Second,  in Table 1 in § 1054.245(b), change the order of the words in the 
Table  1 title, and add “ with displacement ” to the title,  so that the title text 
changes from “ TABLE 1: ENGINES GREATER THAN 80 CC HC+NO
x 
(NMHC+NO x) AND CO ASSIGNED DETERIORATION FACTORS FOR SMALL 
VOLUME ENGINE MANUFACTURERS” to “ Assigned HC+NO x (NMHC+NO x) 
and CO deterioration factors for small volume engine manufacturers for engines 
with displacement greater than 80 cc .” 
• Third, in Table 1 in §  1054.245(b) and Table 2 in § 1054.245(c), correct the 
capitaliz ation of the heading row text so that all words have the first letter 
capitalized. 
• Fourth,  in Table 2 in § 1054.245(c), change the text “MANUFACU TURERS ” to 
“manufacturers ” to correct a typographical error.  
• Fifth, in § 1054.245( d), change the text “Table 1 or Table 2 of this paragraph” 
to “Table 1 or Table 2 of this section. ” 
• Sixth, in §  1054.245(e)(1)  change the text “Selective Enforcement Auditing”  to 
“compliance testing.”   
325 • Seventh, in § 1054.245(e)(2), change the text “Table 1 or Table 2 of 
paragraph  (a) of this section” to “Table 1 or Table 2 of this section.”  
Rationale. The rationales  for the Proposed  Amendments to § 1054.245 are as follows:  
• The first and seventh changes are necessary to improve clarity and readability 
by correcting a reference mistake. The current text in §§ 1054.2 45(a) and (e)(2) 
states that Tables  1 and  2 are in § 1054.24 5(a). However, Table 1 and Table 2 
are in §§ 1054.24 5(b) and  (c), respectively.  
• The second, third, and fourth changes are necessary to improve consistency, 
clarity, and readability.  
• The fifth change is necessary to improve clarity and readability by correcting a 
reference mistake. The current text in § 1054.245( d) states that Tables 1 and 2 
are in § 1054.245( d). However, Table 1 and Table 2 are in §§ 1054.245(b) 
and (c), respectively.  
• The sixth change is necessary to prevent confusion for the reader by correcting 
an oversight that occurred at the time the federal regulations were 
incorporated into the California Code of Regulations in 2012.  Federal 
regulations use the ter m “selective enforcement audit” in 40 CFR Part  1068  to 
refer to provisions substantially similar to the provisions that California SORE  
regulations describe as “compliance testing ” for in-use test ing and validation of 
engines in § 2407. However, using  the federal  regulatory phrase here, rather 
than the California regulatory phrase,  could create confusion. The proposed 
terminology change to §  1054.245(e)(1)  would not affect manufacturer actions 
because manufacturers already must follow applicable CCR  § 2407 
requirements and applicable 40 CFR part  1068 requirements.  
§ 1054.245(e)(3)  
Purpose. The Proposed Amendments change the text “CARB  may reject a DF if it has 
evidence that the DF is not appropriate for that engine family within 30 days of receipt 
from th e manufacturer” to  “CARB may reject a DF if the DF is not appropriate for that 
engine family.”  The purpose of this change is to remove  an arbitrary cutoff period for 
CARB’s r eview of deterioration factors.  
Rationale . This change is necessary because the cutoff period of 30 days may be 
inadequate for such a critical component of the certification evaluation. D eterioration 
factors are used in calculating the lifetime emission impacts of certified engine families . In order to quantify and realize the expecte d emission benefits of the SORE  
regulation s, the deterioration factors used for these calculations for certification must 
be accurate, otherwise excess emissions may occur. CARB must have the authority to 
reject a DF at any time during the certification ap plication review process should 
information come to light that indicates a DF is not appropriate. A manufacturer may 
not be forthcoming with information regarding how its DF was determined. It is therefore necessary for CARB to preserve the right to reject a DF based on a lack of  
326 information that suggests a DF is appropriate for the engine family. The proposed 
change clarifies that the burden is on a manufacturer to demonstrate that a DF is 
appropriate rather than the burden being on CARB to demonstrate that a DF is not 
appropriate.  
§ 1054.245(e)(4)  
Purpose. The Proposed Amendments remove the text “families and” from 
§ 1054.245(e)(4) , as indicated by the strikeout text in the following: “(4) Calculated 
deterioration factors may cover families and  model years  in addition to the one upon 
which they were generated  if the manufacturer submits a justification acceptable  to 
the Executive Officer in advance of certification that the affected engine families can be reasonably expected to have similar emission deterioration characteristics.”   
Rationale . This change is necessary to ensure that a manufacturer’s engines whose 
emission characteristics are sufficiently similar to share a DF are grouped into one engine family rather than being split into two or more engine f amilies. D eterioration 
factors are used in calculating the lifetime emission impacts of certified engine 
families . In order to quantify and realize the expected emission benefits of the SORE  
regulation s, the deterioration factors used for these calculations for certification must 
be accurate, otherwise excess emissions may occur. Any manufacturer who previously 
used a DF from one family for another family could combine those families into one 
family without any significant impact.  
§ 1054.250(a)  
Purpose. The current regulations in § 1054.250 specify the records a manufacturer 
must keep and the reports a manufacturer must send to CARB. Subsection (a) specifies 
the address to which the manufacturer must send information related to its California -
directed p roduction volumes and its end -of-year report describing information about 
engines produced during the model year. The Proposed Amendments change t he text 
“Mobile Source Operations Division”  to “Emissions Certifi cation and Compliance 
Division” because of the reorganization of divisions within CARB . In addition, the 
Proposed Amendments change “9528 Telstar Avenue, El Monte, California 91731” to 
“4001 Iowa Street, Riverside, CA 92507” to reflect the address of CARB’s new 
Southern California headquarters.  
Rationale . These changes are necessary because CARB divisions have been 
reorganized and renamed, and construction of the new Southern California headquarters has been completed. The Emissions Certification and Compliance Division now has  responsibility for re viewing certification  applications , so the division 
name has been updated.  Division staff and the vehicle emissions testing  laboratories 
will be housed at the new headquarters.   
327 § 1054.250(c)  
Purpose. The current regulations in § 1054.250(c)  specify  the following,  consistent  with 
federal  regulations prior  to June 2021:  
“Keep data from  routine  emission tests  (such as test cell temperatures  and 
relative  humidity readings)  for one year after  we issue the associated  certificate  
of conformity.  Keep  all other  information  specified in this section  for eight  years  
after we issue your certificate.”  
U.S. EPA’s  final regulatory amendments,  “Improvements  for Heavy- Duty Engine and 
Vehicle Test Procedures,  and Other  Technical  Amendments,”  published  in the Federal  
Register  on June  29, 2021, includes the following amended  text for 40 CFR Part 
1054.250(c) : 
“Keep  required  data from  emission tests and all other  information  specified  in 
this section  for eight  years  after  we issue your certificate.  If you use the same  
emission data or other  information  for a later model  year,  the eight -year period  
restarts  with each  year that you continue to rely on the information.”  
The Proposed  Amendments would  incorporate  the above  U.S. EPA amendment  into 
California Part 1054.250(c)  to harmonize  the California Code  of Regulations  with the 
recent  federal  regulation  changes,  as indicated by underline and strikeout  in the 
following text: 
“Keep  required  data from  routine  emission tests (such  as test cell temperatures  
and relative  humidity readings)  for one year after we issue the associated  
certificate  of conformity.  Keep  all other  information  specified  in this section  for 
eight  years  after  we issue your certificate  and all other  information  specified  in 
this section  for eight  years  after  we issue your Executive  Order.  If you use the 
same  emission data or other  information  for a later model  year,  the eight -year 
period  restarts  with each  year that you continue to rely on the information . 
The Proposed Amendments include one modification specific to California SORE 
regulations: change “certificate of conformity” to “Executive Order.”  
Rationale . These changes are necessary to provide consistency with (i.e., “harmonize”) 
recent changes made to  the corresponding provisions in the federal Part 1054 . The 
proposed changes would not result in cost impacts to manufacturers because they align CCR requirements with federal requirements that manufacturers already must 
follow. Changing the text “certificate of conformity” to “Executive Order” is necessary 
to prevent confusion for the reader. CARB  uses the term “Executive Order” to refer to 
the certification document for an engin e family for sale  or lease for use in California.  
U.S. EPA uses  the term “certificate of conformity,” shortened to “certificate .” The 
proposed change ensures consistent use of California -specific terminology throughout 
the regulations. See the Global Amendments subsection, “ “EPA” to “CARB” Term 
Change, “Certificate of Conformity” to  “Executive Order” Term Change,  and  
328 Improvements to References to Parts 1054 and 1065,” in this section F for additional 
explanation.  
Subpart I – Definitions and Other Reference Information 
§ 1054.820  
Purpose. Section  1054.820 provides a reference to Subchapter 1.25, Title 17, 
California Code of Regulations , §§ 60040, et seq ., to inform manufacturers and oth er 
interested parties how to request a hearing. The Proposed Amendments delete thi s 
reference and add the following reference: “Chapter 15, Title 13, California Code  of 
Regulations, Section 2771.”  
Rationale . This change is necessary to help ensure manufacturers reference the curren t 
hearing procedures because the referenced provisions in Title 17 have been repealed. 
The provisions in Title 13 CCR § 2771 and its internal references to the A dministrative 
Hearing Procedures for Petitions for Review of Executive Officer Decisions (T itle 17, 
California Code of Regulations, Division 3 , Chapter 1 , Article 2, commencing with 
§ 60055.1) provide the current hearing procedures.  
§ 1054.825  
Purpose. Section  1054.825 in the federal Part  1054 and California’s Part  1054 describe 
reporting and recordkeeping requirements that apply under this part . Because 
U.S. EPA’ s final regulatory amendments published in June 2021 extensively amended 
and reformatted the federal §  1065.825, the Proposed Amendments replace the 
entirety of §  1054.825  with text formatted to mirror the current organization of the 
federal Part 1054.825. The Proposed Amendments include several modifications to 
make the recent federal  amendments specific to California, as described in the 
following in strikeout and underline. The Proposed Amendments omit references to 
federal regulations not adopted by CARB and without a California equivalent, and add 
“[Res erved]” in their place to preserve the numbering continuity and consistency with 
the numbering of the federal 1054.825 subsections.  
“(a) This part includes  various  requirements  to submit  and record  data or other  
information.  Unless we specify  otherwise,  store  required  records  in any format 
and on any media  and keep  them  readily available for eight  years  after  you send  
an associated  application for certification,  or eight  years  after  you generate the 
data if they do not support  an application for certification.  We may request  
these  records  at any time.  You must  promptly give us organized,  written  
records  in English if we ask for them.  This requir ement  to give us records  
applies  whether  or not you rely on someone else to keep  records  on your 
behalf.  We may require you to submit  written  records  in an electronic format.  
(b) The regulations in § 1054.255 and 40 CFR 1068.25 and 1068.101 and in 
Title 13, California Code  of Regulations,  sections 2405- 2409,  describe  your 
obligation to report  truthful  and complete  information.  This includes  
329 information  not related  to certification.  Failing to properly report information  
and keep  the records  we specify  viola tes 40 CFR 1068.101(a)(2),  which  may 
involve  civil or criminal  penalties.  If you fail to properly report information  and 
keep  the records  we specify,  we may suspend,  revoke,  or void the executive  
order  for the engine family involved,  and you may be subject  to civil or criminal  
penalties.  
(c) Send  all reports  and requests for approval  to the Designated  Compliance  
Officer  (see §1054.801).  
(d) Any written  information  we require  you to send  to or receive  from  another  
company is deemed  to be a required  record  under  this section.  Such  records  
are also deemed  to be submissions to EPA CARB . We may require  you to send  
us these  records.  
(e) Under  the Paperwork  Reduction  Act (44 U.S.C. 3501  et seq.,),  the Office  of 
Management  and Budget  approves  the reporting  and recordkeeping  specified  
in the applicable  regulations in this chapter.  The following items  illustrate  the 
kind of reporting  and recordkeeping  we require  for engines  and equipment  
regulated  under  this part:  
(1) We specify  the following requirements  related  to engine  and equipment  
certification  in this part 1054: 
(i-iii) [Reserved]  
(i) In § 1054.20  we require  equipment  manufacturers  to label  their equipment  if 
they are relying  on component  certification.  
(ii) In § 1054.135  we require  engine manufacturers  to keep  certain  records  
related  to duplicate  labels sent to equipment  manufacturers.  
(iii) In § 1054.145  we include various  reporting  and recordkeeping  requirements 
related  to interim provisions.  
(iv) In subpart  C of this part we identify a wide  range  of informatio n required  to 
certify engines.  
(v-vi) [Reserved]  
(v) In §§ 1054.345  and 1054.350 we specify  certain  records  related  to 
production -line testing.  
(vi) [Reserved]   
330 (vii) In subpart  G of this part we identify several  reporting  and recordkeeping  
items  for making demonstrations and getting  approval  related  to various  special  
compliance  provisions.  
(viii) [Reserved]  
(viii) In §§ 1054.725,  1054.730,  and 1054.735 we specify  certain  records  related  
to averaging,  banking,  and trading.  
(2) [Reserved]  
(2) We specify  the following requirements  related  to component  and equipment  
certification  in 40 CFR part 1060:  
(i) In 40 CFR 1060.20 we give an overview  of principles for reporting  
information.  
(ii) In 40 CFR part 1060,  subpart  C, we identify  a wide  range  of information  
required  to certify products.  
(iii) In 40 CFR 1060.301  we require  manufacturers  to keep  records  related  to 
evaluation  of production  samples for verifying  that the products  are as specified  
in the certificate  of conformity.  
(iv) In 40 CFR 1060.310  we require  manufacturers  to make  components,  
engines,  or equipment  available for our testing  if we make  such a request.  
(v) In 40 CFR 1060.505 we specify  information  needs for establishing various  
changes  to published  test procedures.  
(3) We specify  the following requirements  related  to testing  in 40 CFR 
pPart 1065:  
(i) In 40 CFR Part 1065.2  we give an overview  of principles for reporting  
information.  
(ii) In  40 CFR Part 1065.10  and 1065.12 we specify  information  needs  for 
establishing  various changes to published  test procedures.  
(iii) In  40 CFR Part 1065.25  we establish basic  guidelines for storing  test 
information.  
(iv) In 40 CFR Part 1065.695  we identify the specific information  and data items  
to record  when measuring  emissions.  
(4) [Reserved]   
331 (4) We specify  the following requirements  related  to the general  compliance  
provisions  in 40 CFR part 1068:  
(i) In 40 CFR 1068.5  we establish a process  for evaluating  good  engineering  
judgment  related  to testing  and certification.  
(ii) In 40 CFR 1068.25 we describe  general  provisions  related  to sending  and 
keeping  information.   
(iii) In 40 CFR 1068.27 we require  manufacturers  to make  engines  available for 
our testing  or inspection if we make  such a request.   
(iv) In 40 CFR 1068.105  we require  equipment  manufacturers  to keep  certain  
records  related  to duplicate  labels from  engine manufacturers.   
(v) In 40 CFR 1068.120 we specify  recordkeeping  related  to rebuilding engines.   
(vi) In 40 CFR part 1068,  subpart  C, we identify  several  reporting  and 
recordke eping  items  for making demonstrations  and getting  approval  related  
to various  exemptions.   
(vii) In 40 CFR part 1068,  subpart  D, we identify several  reporting  and 
recordkeeping  items  for making demonstrations  and getting  approval  related  
to importing  engines.   
(viii) In 40 CFR 1068.450  and 1068.455 we specify  certain  records  related  to 
testing  production -line engines  in a selective  enforcement  audit.   
(ix) In 40 CFR 1068.501  we specify  certain  records  related  to investigating  and 
reporting  emission- related  defects.  (x) In 40 CFR 1068.525 and 1068.530  we 
specify  certain  records  related  to recalling nonconforming  engines.   
(xi) In 40 CFR part 1068,  subpart  G, we specify  certain  records  for requesting  a 
hearing .” 
Rationale . These changes are necessary to harmonize California’s Part 10 54 with 
amendments to the  federal  Part 10 54 adopted by U.S.  EPA since November 2010, nn 
with modifications  to address California’s specific regulations. The changes listed are 
otherwise identical to the changes in the same- numbered section  of the federal 
Part 1054. These changes are proposed  for the reasons described in the Global 
                                            
nn CARB incorporated portions of the federal Part 1054 into the California Code of Regulations in 
October 2012. The California Part 1054 adopted in 2012 is based on the federal text as of 
November  8, 2010.   
332 Amendments subsection, “ Updates to Harmonize with Amended Federal Text ,” in this 
section  F of this chapter.  
G. California Exhaust Emission Standards and Test Procedures for New 2013 
and Later Small Off -Road Engines; Engine -Testing Procedures ( Part 1065) 
This section provides a summary, purpose, and rationale for each Proposed 
Amendment to the California Exhaust Emission Standards and Test Procedures for 
New 2013 and Later Small Off -Road Engines ; Engine- Testing Procedures ( Part 1065 ), 
referred to herein as “Part  1065”. These standards and test procedures are 
incorporated by reference in Title  13, CCR, § 2403. Appendix G of this Staff Report 
provides the full  proposed regulatory language of these standards and test 
procedures  with Proposed Amendments shown in strikeout and underline formatting.  
Global Amendments throughout Part 1065  
“ARB” to “CARB” Acronym Change  
Purpose. The Proposed Amendments change “ARB” and “the ARB” to “CARB ,” and 
add “California” before  “Air Resources Board ,” for consistency with recent CARB 
document style practices designed to improve clarity. 
Rationale . This change reflects the California Air Resources Board’s recent change to, 
and pr eferred use of, the acronym “CARB” versus the prior acronym, “ARB,” and the 
entire agency title, “California Air Resources Board.”  
Capitalization Change  
Purpose. The Proposed Amendments change the formatting of text in all capital 
letters to mixed case to aid in making documents accessible to everyone, including 
people with visual impairments and assistive technology users.  
Rationale . Mixed case words and sentences are easier to read and consistent with 
current accessibility guidelines.  
Grammar Change to “O wner’s Manual”  
Purpose. The Proposed Amendments change t he phrase  “owners manual” to 
“owner’s manual” by adding an apostrophe in §§  1065.525 and 1065.930.  
Rationale . This change is necessary to correct nonstandard grammar in the previously 
adopted text. T he term “owner’s manual,” with the possessive apostrophe, is the 
correct grammar for referencing the document . California Administrative Law (Title  1, 
CCR, § 16(a)(4) ) requires that California regulations be free of grammatical errors, 
which may create confusion or ambiguity or undermine the perceived 
authoritativeness of the regulation text. It is essential to satisfying the purpose of this  
333 regulation and addressing the identified problem that there be no such real or 
perceived ambiguity or error in language use in the regulatory text.  
Table of Contents C hange  
Purpose. The Proposed Amendments adjust p age numbers to accommodate added or 
removed text throughout  Part 1065. Amendments to the Table of Contents reflect 
these changes.  
Rationale . Amending the pa ge numbers is necessary for accuracy and to prevent 
confusion for the reader.  
“Reserved” Placeholder Added  
Purpose. The Proposed Amendments add the placeholder text “[Reserved ]” to the 
following sections: 1065.122(b), 1065.130(g), f ootnote (c) of Table 1 of 1065.303, 
1065.307(e)(3)(iv), 1065.307(e)(3)(vi), 1065.320(b), 1065.510(g), 1065.530(i), 
1065.602(l)(1), 1065.610(d)(3) , 1065.670(a), 1065.1010(b)(1- 23), 1065.1010(b)(25 -27), 
1065.1010(b)(29- 32), 1065.1010(b)(34), 1065.1010(b)(37- 39), 1065.1010(b)(41- 46), 
1065.1010(c)(2), 1065.1010(d), 1065.1010(e)(1- 14). The purpose of these changes is to 
prevent gaps in the numbering and lettering of provisions while ensuring that 
provisions within Part 1065 that are similar or analogous to pro visions within 
U.S. EPA’s  Title 40, Code of Federal Regulations, Part 10 65 (“federal Part 1065”)  have 
the same numbering  and lettering.  
Rationale . These changes are necessary to maintain sequential section numbering and 
lettering in order to improve readability and prevent confusion for readers.  The 
incorporation of Part 1065  into the California Code of Regulations in 2012, and the 
Proposed  Amendments, include a number of changes to text in the federal Part 10 65 
necessary to address California -specific applicability, emissio n standards, engine 
cooling, PM emission calculations, test fuels, lubricants, and definitions that  support 
California’s unique air quality programs . Some of these changes involved the deletion 
of portions  of the federal text that contain  provisions that a re redundant with, or in 
conflict with, other California SORE regulations.  In some cases, the subsection was 
deleted but subsequent items at the same numbering level were retained . The 
resulting gaps in numbering of provisions would make the regulation mor e difficult to 
follow. R enumbering those provisions adopted or retained to eliminate gaps would 
result in similar provisions within the federal and California regulations being referred 
to by different subsection or paragraph numbers. The insertion of the “[Reserved]” 
placeholder preserves the similar numbering while removing any gaps in sequential 
numbering of provisions. 
Calibration Requirements Change  
Purpose. The Proposed Amendments change the requirement to use National 
Institute of Standards and Technology (NIST) -traceable mass standards  to instead 
allow the use of Système  International  d'Unités (SI)-traceable mass standards through  
334 NIST or another member of the Mutual Recognition Arrangement  of the Comité 
International des Poids et Mesures (CIPM  MRA ), and add a definition for 
“SI-traceable” in §  1065.1001.  
Rationale . Requiring  SI-traceable standards is consistent with current industry practice 
and is necessary to allow flexibility for manufacturers around the world to  use other 
recognized international  standards  while still maintaining the consistency necessary to 
ensure test data accuracy, precision, and comparability to the emission standards, as 
well as a level playing field amongst manufacturers. Accurate and precise data are 
necessary to ensure that engines determined to be in compliance with emission  
standards assessed using Part  1065 are indeed compliant and do not result in excess 
emissions.  
Improvements to References  to California Code of Regulations  
Purpose. The Proposed  Amendments make  the following changes to references to 
regulations:  
• Change the abbreviation “ 13, CCR”  to spell out “Title 13, California Code of 
Regulations” in § 1065.701(a)(2).  
• Re-locate “Title  13” to precede “California Code of Regulations” where it 
currently incorrectly follows that text in § 1065.701(a)(1).  
• Add the text “California Code of Regulations” where previously implied 
between “Title 13” and a section number in § 1065.701(a)(2).  
• Remove “of the” where it occurs between “Title 13” and “California Code of Regulatio ns” in § 1065.1001.  
Rationale . These changes are necessary to better identify the body of regulations to 
which these subsections refer, to satisfy the clarity requirements under  California 
Administrative Law (Title 1, CCR, § 16), and to better differentia te them from the 
federal regulations. “CCR” is used in some places within this part, “California Code of 
Regulations” in others, and “Title 13” without elaboration in others still. Although the 
existing references are sufficient to identify the regulations, t he use of different forms 
of reference could  confuse parties subject to the regulation s, as it may create the 
impression that these are different references. It is essential to satisfying the purpose 
of the regulations and addressing the identified problem that they be understandable 
to the regulated parties, including where references are made to other regulation s, 
and that there is no real or perceived ambiguity in such references.   
335 “EPA” to “CARB” Term Change, “Certificate of Conformity” to “Executive 
Order” Term Change, and Improvements to References to Part 1054 
Purpose. The Proposed  Amendments make  the following changes throughout  
Part 1054:  
• Change “EPA” to “CARB”  in §§ 1065.1(c), 1065.2(a), 1065.2(b), 1065.2(c), and 
1065.5 14(a).   
• Remove the definition for EPA in § 1065.1001 Definitions, “EPA means Air 
Resources Board.”  
• Change “certificates” to “Executive Orders” in §  1065.2(c).  
• Remove the definition entry for “certificate of conformity” in §  1065.1001.  
• Change “40 CFR 1054 ” to “Part 1054” in § 1065.1001. 
• Change “§1054.505” to “Part 1054, § 1054.505” in §  1065.1001 .  
• Change “CFR part 1054” in § 1065.1(d) to “California Exhaust Emission Standards and Test Procedures for New 2013 Small Off -Road Engines; Engine-
Testing Procedures (Part 1054),” adopted October 25, 2012, and amended 
[insert amended date], hereinafter referred to as part 1054.” The Proposed 
Amendments include a placeholder for the amended date, “ [insert amended 
date] ”, that will be updated to reflect the CARB adoption date of the Prop osed 
Amendments to Part 1054, which are described in section F earlier in this 
chapter, and provided in their entirety in Appendix F.  
Rationale . These cha nges are necessary to  improve clarity and regulatory certainty. In 
2012, CARB modified the SORE regula tions to adopt portions of the federal Part 1054 
and Part 1065, to improve alignment of the certification and testing requirements 
without any changes in the stringency of the emission standards and associated test 
procedures, and without any cost impacts.  Certain sections, section titles, subsections, 
or paragraphs, which were adopted without making other changes, contain references 
to U.S.EPA  and certificate of conformity carried over from the origi nal federal text. 
U.S. EPA uses  the term “certificate of conformity,” shortened to “certificate .” CARB  
uses the term “Executive Order” to refer to the certification document for an engine 
family for sale or lease for use  in California. In the 2012 adoption this was dealt with by 
adding definition entr ies clarifying that the terms “EPA” and “certificate of 
conformity” or “certificate”  should be understood to refer to CARB and Executive 
Order, respectively, for the purposes of California’s Part 1054 and Part 1065. 
However, as much of the document must be re viewed before one reaches these 
definition entr ies, a potential for confusion still exists. This proposed  amendment 
ensures that the intended meaning of these references is immediately clear to 
regulated parties and other stakeholders. Changing “EPA” to “C ARB” and removing 
the definition for U.S.  EPA are necessary to provide consistency with the incorporation 
of federal regulations into California’s SORE regulations and to  clarify that the 
California Air Resources Board is the agency having jurisdiction and decision-making  
336 authority under th ese regulation s and is the agency to which reports must be 
submitted.  It is essential to satisfying the purpose of the regulations and addressing 
the identified problem that there be no real or perceived ambiguity regardi ng the fact 
that the California Air Resources Board is the agency having jurisdiction and decision-
making authority under this part, and the agency to which reports must be submitted.  
Changing “certificate of conformity” and “certificate” to “Executive Ord er” and 
removing the definition for “certificate of conformity” would provide consistent use of California- specific terminology throughout the regulations, which better distinguishes 
them from the federal regulations and prevents confusion for manufacturers and other 
readers. These Proposed Amendments do not change any of the standards and test 
procedures.  
In addition, t he current regulations in Californ ia’s Part 1065  refer to Part 1054 in some 
places . The Proposed Amendments clarify that the referenced test procedures and 
other requirements are those specified in California’s Part 1054, rather than the same -
numbered paragraphs in the similar f ederal procedures.  The test procedures and other 
requirements in California’s Part 1054 are the ones that properly a pply to testing to 
address California requirements. Providing explicit referenc es to the California SORE  
regulations in all places where the test procedures and other requirements contained 
therein are referenced prevents  ambiguity and potential conflict. It is essential to 
satisfying the purpose of the regulations and addressing the identified problem that 
the test procedures and other requirements referenced here be consistent and understandable to the regulated parties, including where references are mad e to 
other regulation, and that there is no real or perceived ambiguity or conflict in regulatory instructions to regulated parties.  
Furthermore, the change to “Part 1054” the first place it is specified is necessary to 
ensure the amended test procedures a re used for certification and compliance testing 
once they become effective. The most up -to-date test procedures must be followed 
by all manufacturers of MY  2013 and subsequent model year engines to ensure SORE 
meet the emission standards. Adding the amendment dates for the test procedures clarifies the versions of the test procedures that must be used.  
Updates  to Harmonize with Amended Federal Text  
Purpose. Subsequent to CARB’s adoption of Part 1065 into the California Code of 
Regulations, U.S.  EPA made a number of terminology changes and other amendments 
to the federal Part 1065. The Proposed Amendments revise  portions of California’s 
Part 1065 to provide consistency with (i.e., “harmonize”) these recent changes made 
to the wording of corresponding provisions in the federal Part 1065. These proposed 
harmonization amendments reflect changes made to the federal regulations after  
337 June 28, 2011,oo up to and including U.S.  EPA’s final regulatory amendments, 
“Improvements for Heavy- Duty Engine and Vehicle Test Procedures, and Other 
Technical Amendments,” published in the Federal Register on June  29, 2021.  
There are two types of proposed harmonization amendments to California’s Part 1065 : 
(1) Amendments that provide the exact same words and organizational changes a s 
U.S. EPA’s recent amendments to the federal Part 1065 ; and (2) Amendments that 
provide U.S. EPA’s recent amendments with one or more modifications to incorporate 
California- specific changes necessary to maintain the stringency of California emission 
standards, provide consistency with existing California SORE regulations or other 
Proposed Amendments described in this staff report, or prevent confusion. T he 
proposed harmonization  amendments that include one or more California -specific 
modifications each have their own separate purpose and rationale descriptions that, 
along with the purpose and rationale descriptions for other Proposed Amendments to 
California’s Part 1065, follow the “Global Amendments” subsection of this section G in 
the order in which they  occur in the regulations. The following “Harmonization with 
Document -wide or Repeated Federal Changes” and “Harmonization with Section-
Specific Federal Changes” subsections  identify the sections, subsections, and 
paragraphs of California’s Part 1065 with proposed harmonization amendments that 
provide the exact same words  and organizational changes  as U.S. EPA’s recent 
amendments to the federal Part 1065. 
Harmonization with Document- wide or Repeated Federal Changes 
The Proposed  Ame ndments change the following  terms  in California Part 1065 where  
U.S. EPA made  such changes in the corresponding  federal  Part 1065: 
• Change “water” to “H 2O” in the following sections: 1065.342 (d)(2), 
1065.3 50(d)(2), 1065.350(d)(4), 1065.355(d)(2), 1065.355(d)(4), 1065.370(e)(5), 
1065.3 75(d)(2), 1065.375(d)(4), 1065.376(b), 1065.376(d)(vi), and 
1065.3 76(d)(viii), 1065.655(c)(3).  
• Change “Diluent” to “dilution air” in the following sections: 1065.140(a), 
1065.1 40(b), 1065.140(b)(1), 1065.140(e)(1- 3), and 1065.905(d)(2)(i)(A) . 
• Change “Validate” and its conjugations to “verify” and corresponding conjugations thereof in the following sections: 1065.140(c)(7), 1065.140(d)(3)(v), 1065.1 70(a)(1), and 1065.546.  
• Change “rev/min” to “r/min” in the following sections: 1065.20(a)(1), 1065.6 50(d)(7), 1065.650(e)(4), and 1065.1005.  
                                            
oo CARB incorporated portions of the federal Part 1065 into the California Code of Regulations in 
October 2012. The California Part 1065 adopted in 2012 is  based on the federal text as of 
June 28, 2011.  
338 • Change “Methane” to “CH 4“ in the following sections: 1065.365(b), 
1065.3 65(f), 1065.520(f) (1065.520(g) in the previous text), and 1065.750(a)(2)(v).  
• Change footnote reference marks of the form “1, 2, 3…” to the form “a, b, c…” 
in the following tables: Table 1 of 1065.750, Table 1 of 1065.905, Table 1 of 
1065.9 15, 1065.1005(a), and 1065.1005(f)(2).  
• Change the text “2- stroke” and “4 -stroke” to “two -stroke” and “four -stroke,” 
respectively, and add the text “at or” before “below  kW, i n the following 
paragraphs and sections: 1065.145(c)( 2)(ii), 1065.145(d)(1)(ii), 1065.145( e)(2)(ii), 
1065.145(e)(3)(ii), 1065.230(d)(2), 1065.240(d)(2), and 1065.260(c).  
• Delete trailing zeros, and decimal points followed by zeroes, from specified percentages in the following sections: 1065.341(f)(5) [re- lettered to 
subsection (e) in the Proposed Amendments in Appendix G], Table 2 of 
1065.5 14, and Table 1 of 1065.915.  
The Proposed  Amendments change the following  phrases  in the California P art 1065  
where U.S. EPA made  such changes in the corresponding  federal  Part 1065:  
• Change the text “Linearity checks are required” to  “Linearity verification is 
required” in the following sections: 1065.307(e)(7), 1065.307(e)(7)(ii), 1065.3 07(e)(8), 1065.307(e)(8)(ii). Change the text “linearity checks” to  “linearity 
verification” in the following sections: 1065.307(e)(7)(i), 1065.307(e)(8)(i), and 
1065.695.  
• Change the text ”If the sample is [is not] passed through a dryer” to  “If the 
sample does [does not]  pass through a dryer” in the following sections: 
1065.3 50(d)(2) and 1065.375(d)(2)  
• Change references to an H
2O content "greater than or equal to" or "at least as 
high as" to  "at or above" a specific level in the following sections: 
1065.3 09(d)(2), 1065.350(d)(2), 1065.370(d)(5), and 1065.375(d)(2).  
• Footnote reference marks “1, 2, 3…” to “a, b, c…” in Table 1 of §§  1065.750,  
1065.9 05, 1065.915, and in unnumbered tables in 1065.1005(a)  and 
1065.1005 (f)(2).  
• Change instructions to control the vessel temperature to generate an acceptable H
2O level to  instructions to humidify the test gas to an acceptable 
H2O level in the following sections: 1065.309(d)(2), 1065.350(d)(2), 
1065.3 70(e)(5), and 1065.375(d)(2).  
The Proposed  Amendments also add or delete the following text in multiple sections:  
• In § 1065.201(b), add the text “You may generally use instruments with 
compensation algorithms that are functions of other gaseous measurements and the known or assumed fuel properties for the test fuel. The target value for any compensation algorithm is 0% (that is, no bias high and no bias low), 
regardless of the uncompensated signal's bias.” Delete similar provisions  
339 referring individually to specific analyzer types from the following sections: 
1065.250(b) , 1065.260(b), 1065.270(b), 1065.272(b),  1065.275(b)(1), 
1065.275(b)(2), 1065.3 75(d)(3) [renumbered to (d)(4)], 1065.280(b), 1065.284(b), 
and 1065.295(b).  
• Add text allowing humidification of a gas flow by using a device that introduces distilled H
2O as vapor into a controlled gas flow, as an alternative to 
humidification by bubbling gas through distilled H 2O, to the following sections: 
1065.3 09(d)(2), 1065.350(d)(2), 1065.355(d)(2), 1065.370(e)(5), and 
1065.3 75(d)(2).  
Harmonization with Section -Specific Federal Changes  
Harmonization Updates: Subpart A – Applicability and General Provi sions  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  A: 
• In § 1065.1(g), add the text indicated by underline in the following: “For additional 
information regarding these test procedures  in this part, visit our Web site … .” 
• In § 1065.10(a), change the text  “certain exceptions listed in this section” to 
“certain exceptions noted in this section.”  
• In § 1065.10(c)(6), add the text “This also applies for changes to test procedures 
specified in the standard -setting part to the extent that these changes do not 
correspond to new emission standards .”  
• In § 1065.10(c)(7), change the text, “allowed” to “specified” and add the 
sentence, “We may perform tests with your engines using either the approved alternate procedures or the specified procedures.”  
• Add “Advance approval” as a paragraph title for 1065.10(d).  
• In § 1065.12( a), change the text “based on this information alone, or, as 
described in this section, we may ask you to submit to us in writing  submit 
supplemental in formation ” to “based on this information alone,  whether or not 
it includes all the information specified in this section. Where we determine that 
your original submission does not include enough information for us to 
determine that the alternate procedure is equivalent to the specified procedure, we may ask you to submit supplemental information .” 
• In § 1065.12(d), add text that states  that not all submitted information may be 
necessary for an alternate procedure approval and an example of such a case is given. In addition, change the text, “we may ask you to send the following 
information to fully evaluate your request :” to “we may ask you to send .” 
• In § 1065.12(e),  delete  the first sentence, “ We may give you specific directions 
regarding methods for statist ical analysis, or we may approve  other methods 
that you propose” and add the text “ We may give you specific directions 
regarding methods for statistical analysis, or we may approve other methods  
340 that you propose. Such alternate methods may be more or less stringent than 
those specified in this paragraph (e). In determining the appropriate statistical 
criteria, we will consider the repeatability of measurements made with the 
reference procedure. For example, less stringent statistical criteria may be appropr iate for measuring emission levels being so low that they adversely 
affect the repeatability of reference measurements. ” 
• In §§ 1065.15(a)(2), 1065.15(a)(2)(i) and 1065.15(a)(2)(ii), change “hydrocarbons” 
to “hydrocarbon ” add a new paragraph (iii) relating to nonmethane -nonethane 
hydrocarbon, and renumber paragraphs (iii) and (iv) as paragraphs (iv) and (v), respectively.  
• In § 1065.15(b), add the text, “Note also that the standard -setting part may 
include standards for pollutants not listed in paragraph (a) of this section.” 
• In § 1065.15(c)(2)(ii), change the text “HC, CO, and NO
x” to “NO X, HC, CO, 
CO 2, CH 4, N 2O, and CH 2O.” 
• In § 1065.20(a) , delete the reference details for NIST Special Publication 811 
and the associated web  link, and change the text “Note the following 
exceptions” to “The following exceptions apply.”  
• In § 1065.20(a)(1) , change the text “rotational frequency” to  “angular speed.” 
Change the text “reciprocal seconds” to  “radians per second (rad/s).” Delete 
the sentence addressing symbol choice for rotational frequency.  
• In § 1065.20(a)(3), add the word “generally” to a statement that temperatures 
are designated in degrees Celsius.  
• In § 1065.20(c), add the text “A lways use absolute pressure values for 
multiplying or dividing by pressure.”  
• In § 1065.20(e), change the text “ Unless the standard -setting part specifies 
otherwise, round only final values, not intermediate values. Round values to the 
number of significant digits necessary to match the number of d ecimal places of 
the applicable standard or specification. For information not related to 
standards or specifications, use good engineering judgment to record the 
appropriate number of significant digits. ” to “You are required to round certain 
final values , such as final emission values. You may round intermediate values 
when transferring data as long as you maintain at least six significant digits 
(which requires more than six decimal places for values less than 0.1), or all significant digits if fewer tha n six digits are available. Unless the standard -
setting part specifies otherwise, do not round other intermediate values. Round 
values to the number of significant digits necessary to match the number of 
decimal places of the applicable standard or specifi cation as described in this 
paragraph (e). Note that specifications expressed as percentages have infinite precision (as described in paragraph (e)(7) of this section). Use the following rounding convention, which is consistent with ASTM E29 and NIST SP 81 1:.”  
• In § 1065.20(g) , add the parenthetical  text “dry-to-wet corrected, if applicable .”  
341 • Delete the unnumbered paragraph 1065.25 and add new paragraphs 
designated (a), (b), and (c), which describe recordkeeping and reporting 
requirements.  
Harmonization Updates: Subpart B – Equipment Specifications  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  B: 
• In § 1065.125(e)(1),  change the text,  ”and completely close all drains before 
starting a duty cycle.  Keep the drains closed during the emission test” to  
“Before starting a duty cycle (or preconditioning for a duty cycle), completely close all drains that would normally be closed during in- use operation. Keep 
those drains closed during the emission test.”   
• In § 1065.130(a), add the text,  “We refer to exhaust piping as an exhaust stack; 
this is equivalent to a tailpipe for vehicle configurations. ”  
• In paragraph 1065.130(c)(6) , add recommendations for configuring exhaust 
stacks to ensure mixing for raw or dilute partial -flow emission sampling, and a 
statement that mixing considerations may be disregarded in dilute full -flow 
sampling.  
• In § 1065.130(e), add “in this chapter” to the end of the first sentence. Change 
the text “a chemical balance of fuel, intake a ir, and exhaust according to 
§ 1065.655” to “carbon balance error verification as described in § 1065.543.”  
• In § 1065.140(a), change the text “synthetic air” to  “purified air,” add a 
statement that references in this part to “dilution air” may include ambi ent air, 
purified air, or nitrogen, and add text addressing multi -stage dilution, primary 
dilution, and secondary dilution.   
• In § 1065.140(c)(1), add text that describes where flexible tubing may, or may 
not, be used in dilution tunnel construction.  
• In § 1 065.140(c)(2), delete the phrases “an engine” and “that engine.” 
• In § 1065.140(c)(2),  add the sentence “ If you dilute directly from the exhaust 
stack, the end of the exhaust stack is considered to be the start of the dilution tunnel. ” 
• In § 1065.140(c)(6)(i ), change the text “dew point” to  “dewpoint.”  
• In § 1065.140(c)(6)(ii)(C), delete the parenthetical “i.e. , 2%.”  
• In § 1065.140(c)(6)(ii)(D), delete the parenthetical “i.e. , 0.5% .”  
• In § 1065.140(e)(1), change the text “select a location to measure this 
temperature. We recommend that you measure this temperature as close as practical upstream of the point” to “select a location to measure this 
temperature  that is as close as practical upstream of the point.”   
342 • In § 1065.140(e)(2), revise the instruction reg arding combing dilution air and 
raw exhaust, and change the text “Base this minimum value on the maximum 
engine exhaust flow rate for a given test interval ” to “ Base this minimum value 
on the maximum engine exhaust flow rate during a given duty cycle for discrete -mode testing and on the maximum engine exhaust flow rate during a 
given test interval for other testing. ” 
• In § 1065.140(e)(3), change the residence time values from “1 to 5” to 
“1.0 to 5.0.”   
• In § 1065.145(c)(1), change the term “tailpipe” to “stack.” 
• In § 1065.145(e)(3)(i), change the text “it must be heated to prevent aqueous 
condensation” to “design the sampling system to prevent aqueous condensation.”  
• In § 1065.170(a)(1), add the sentence “ You must exclude from the proportional 
sampling verifica tion any portion of the test where you are not sampling 
emissions because the engine is turned off and the batch samplers are not 
sampling, accounting for exhaust transport delay in the sampling system.” Add 
the text indicated in underline and strikeout in the following: “ For example, do 
not use sample bags for storing emissions if the bags are permeable with respect to emissions or if they  offgas  off gas  emissions to the extent that it 
affects your ability to demonstrate compliance with the applicable gaseous 
emission standards in this chapter . As another example, do not use PM filters 
that irreversibly absorb or adsorb gases to the extent that it affects  your ability 
to demonstrate compliance with the applicable PM emission standard in this 
chapter.” 
• In § 1065.170(b) , change the text “the following table” to “Table 1 of this 
section,” add the text “Sample temperatures must stay within the following 
ranges for each container material:,” and add two new paragraphs, 
1065.1 70(b) (1) and (b)(2), that specify the allowable temperature ranges. The 
Proposed Amendments also include California -specific changes to the federal 
text added as paragraph 1065.170(b) (2), wh ich are described in the 
purpose/rationale subsection specific to paragraph 1065.170(b)(2) . 
• In § 1065.170(c)(1)(i), change “ASTM D2986- 95a” to “ASTM D2986 .” 
Harmonization Updates: Subpart C – Measurement Instruments  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  C: 
• In § 1065.201(d), delete the reference to § 1065.25, and change the text “This 
requirements” to “This requirement.”  
• In § 1065.201(h), change the sentence, “Our decision to follow or not follow a 
given  recommendation when testing your engine is not dependent on whether 
or not you followed it during your testing,” to  “Our decision to follow or not  
343 follow a given recommendation when we perform a test does not depend on 
whether you followed it during your testing.”  
• In § 1065.202, add the sentence, “Set up the measurement and recording 
equipment to avoid aliasing by ensuring that the sampling frequency is at least double that of the signal you are measuring, consistent with good engineering judgment; this may require increasing the sampling rate or filtering the signal. ” 
• In Table 1 of § 1065.202, add § 1065.545 to “Applicable Test Section Protocol” column corresponding to “ Sample flow from a CVS that has a heat exchanger .” 
• In Table 1 of § 1065.202, add footno te (a) reference mark to the “Minimum 
command and control frequency” column heading, footnotes (b) and (c) reference marks to the “Minimum recording frequency” column heading, and footnote (d) reference mark to the “Measured values” column entry for “Dilut ion air flow if actively controlled (for example, a partial flow PM sampling 
system) , along with the following footnote text:  
“
a The specifications for minimum command and control frequency do 
not apply for CFVs that are not using active control.  
b 1 Hz means are data reported from the instrument at a higher 
frequency, but recorded as a series of 1 s mean values at a rate of 1 Hz.  
c For CFVs in a CVS, the minimum recording frequency is 1 Hz. The 
minimum recording frequency does not apply for CFVs used to control sampling from a CVS utilizing CFVs.  
d Dilution air flow specifications do not apply for CVS dilution air.”  
• In § 1065.205, change the text “ in subparts D and F of this part or subpart J of 
this part for using PEMS a nd for performing field testing” to  “elsewhere in this 
part for laboratory testing or field testing, as applicable .”pp Change the text 
“the specifications in Table 1 of this section” to “the specifications in this 
section,” and change the text “in Table 1 of this section” to “in the follow ing 
table:.”  
• In § 1065.210(c) , delete the parenthetical quantity symbols and abbreviations:  
(V), (A), (pf), (VA), (VAR)  and (W) . 
• In § 1065.220(a), change the text, “You may use fuel flow in combination with a 
chemical balance of carbon (or oxygen) between the fuel, inlet air, and raw 
exhaust to calculate raw exhaust flow as described in § 1065.650 as follows:” to  
“You may use fuel flow  meters  in combination with a  chemical balance of fuel, 
intake air, and raw exhaust to calculate raw exhaust flow as describ ed in 
§ 1065.655(f). You may also use fuel flow meters to determine the mass flow 
rate of carbon -carrying fuel streams for performing carbon balance error 
                                            
pp PEMS: Portable em ission measurement system.   
344 verification in §1065.543 and to calculate the mass of those fuel streams as 
described in §1065.643. The following provisions apply for using fuel flow 
meters:”  
• Add a new paragraph 1065.220(a)(1)(iii)  with the text, “For calculating the 
dilution air flow for background correction as described in §1065.667.”  
• In § 1065.225(a), change the text “ You m ay use an intake- air flow meter in 
combination with a chemical balance of carbon (or oxygen) between the fuel, inlet air, and raw exhaust to calculate raw exhaust flow as described in § 1065.650, as follows:” to  “You may use intake- air flow meters in combination 
with a chemical balance of fuel, in take air, and raw exhaust to calculate raw 
exhaust flow as described in § 1065655(f) and (g). You may also use intake- air 
flow meters to determine the amount of intake air input for performing carbon 
balance error verification in §  1065.543 and to calculate the measured amount 
of intake air, n
int, as described in §  1065.643. The following provisions apply for 
using intake air flow meters: ” 
• Add new paragraphs 1065.225(a)(1)(iii) and 1065.225(a)(1)(iv) , stating that 
intake -air flow meters may be used for verifying PM batch sampling dilution and 
calculating dilution air flow for background correction . 
• In § 1065.240(d)(3), change the text, “If cooling causes aqueous condensation, 
do not sample NOX downstream of the cooling unless the cooler meets the performance verification in § 1065.376,” to  “The cooling must not cause 
aqueous condensation, as described in § 1065.140(c)(6).”  
• Delete the entirety of §  1065.240(d)( 4). 
• In the section title of  §1065.250 and in paragraph 1065.250(a), change 
“infra -red” to “infrared.”  
• In the section title of §1065.260 and in paragraph 1065.260(a), change “flame -ionization” to “flame ionization.”  
• In § 1065.260(a), change the text  “Determine methane and nonmethane 
hydrocarbon values as described  in paragraph (e)  of this section” to  “For 
measuring THC or THCE you must use a FID analyzer. For measuring CH
4 you 
must meet the requirements of paragraph (f) of this section. ” 
• In § 1065.260(c) , add the text “measuring THC or THCE from.”  
• Delete the entirety of paragraph 1065.260(e)  and add the following paragraph:  
“NMHC and NMOG. For demonstrating compliance with NMHC 
standards, you may either measure THC or determine NMHC mass as described in §1065.660(b)(1), or you may measure THC and CH
4 and 
determine NMHC as described in §1065.660(b)(2) or (3). You may also use the additive method in § 1065.660(b)(4) for natural gas- fueled  
345 engines as described in § 1065.266. See 40 CFR 1066.635 for methods 
to demonstrate compliance with NMOG standards for vehicle testin g.” 
• Add two new paragraphs to §  1065.260, paragraph 1065.260(f), relating to 
determination of nonmethane- nonethane hydrocarbon, and 
paragraph  1065.260 (g), relating to the measurement of methane.  
• In § 1065.265, change the text “NMHC emission” to “CH 4 or NM HC 
emissions.”  
• Add a new section  1065.266, which contains equipment specifications for 
Fourier -transform infrared (FTIR) analyzers used to measure NMHC and 
NMNEHC for continuous sampling  for engines that run only on natural gas.  
• In § 1065.267(a), change the text “ You may use a gas chromatograph to 
measure CH 4” to “You may use a gas chromatograph  with a flame ionization 
detector (GC -FID) to measure CH 4 and C 2H6.”  
• In § 1065.267(b), change the text “We recommend that you use a gas 
chromatograph that meets the  specifications in Table 1 of § 1065.205, and it 
must also meet the linearity verification in § 1065.307” to “We recommend that you use a  GC-FID that meets the specifications in Table 1 of § 1065.205, and 
that the measurement be done according to SAE J1151 (incorporated by 
reference in §1065.1010). The GC -FID must meet the linearity verification in 
§1065.307. ” 
• Add two new paragraphs, 1065.269(a) and 1065.269(b), containing specifications for photoacoustic analyzers for ethanol and methanol.  
• In § 1065.275(b) (1), change the text “infra -red” to “infrared.”  
• In § 1065.275(b)(2), change the text “infra -red” to “infrared,” and change the 
text “ For example, EPA Test Method 320 is considered a valid method for 
spectral interpretation (see http://www.epa.gov/ ttn/emc/methods/method320.html)” to “For example, 
EPA Test Method 320 (see § 1065.266(b)) and ASTM D6348 (incorporated by 
reference in § 1065.1010) are considered valid methods for spectral 
interpretation.”  
• Renumber paragraphs 1065.275(b)(3) and 1065.275(b )(4) as 1065.275(b)(4) and 
1065.2 75(b)(5), respectively. Add a new paragraph 1065.275(b)(3), which 
provides examples of types of laser infrared analyzers.  
• In § 1065.275(c), add the text “ laser infrared analyzers, .” 
• In § 1065.275(c)(1), change the text “ Note that interference species, with the 
exception of H
2O, are dependent on the N 2O infrared absorption band chosen  
346 by the instrument manufacturer and should be determined dently <sicqq> for 
each analyzer. ” to “Note that interference species, with the exceptio n of H 2O, 
are dependent on the N 2O infrared absorption band chosen by the instrument 
manufacturer. For each analyzer determine the N 2O infrared absorption band. 
For each N 2O infrared absorption band, use good engineering judgment to 
determine which interference gases to use in the verification. ”  
• In § 1065.275(c)(2), add the text “and laser infrared analyzers” to the end of the 
first sentence, and change the text “Note that interference species, with the 
exception of H 2O, are dependent on the N 2O inf rared absorption band chosen 
by the instrument manufacturer and should be determined independently for 
each analyzer. ” to “Note that interference species, with the exception of H 2O, 
are dependent on the N 2O infrared absorption band chosen by the instrument  
manufacturer. For each analyzer determine the N 2O infrared absorption band. 
For each N 2O infrared absorption band, use good engineering judgment to 
determine interference gases to use in the verification.”  
Harmonization Updates: Subpart D – Calibrations a nd Verifications  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  D: 
• In § 1065.305(d)(10)(i), delete the text “ in subparts D, F, an d J of this part, as 
applicable.”  
• In § 1065.307(a), change the text “the table” t o “Table 1 of §  1065.303 ,” delete 
the text “Note that this linearity verification may replace requirements we 
previousl y referred to as “calibrations”,” add the text “accurately and,“  and 
change the text “a linearity verification” to “linearity verificatio n.” 
• In § 1065.307(c)(1), change the text “we use the letter “y” to denote a generic 
measured quantity, the superscript over -bar to denote an arithmetic mean (such 
as ӯ), and the subscript “ ref” to denote  the known or reference quantity being 
measured” to “the letter “y” denotes a generic measured quantity, the 
superscript over- bar denotes an arithmetic mean (such as ӯ ), and the subscript 
“ref” denotes the known or reference quantity being measured. ” 
• In § 1065.307(c)(2), change the text “specified temperatures, pressures, and 
flows” to “normal operating conditions.”  
• In § 1065.307(c)(3), (4), and (5), add the text “If applicable,” to the beginning of 
each paragraph.  
• In § 1065.307(c)(6), change the text “instrument manufacturer recommendations” to “the instrument manufacturer’s recommendations,” 
                                            
qq The text “dently” is a typographical error in the 2011 federal text that was inadvertently carried into 
the California regulation during the 2012 adoption process.   
347 change the text “of the linearity verification” to  “for the linearity verification,” 
and add the text “power, current, voltage, photoacoustic analyzers,” to the list 
of types of linearity verifications where three refere nce values are 
recommended.  
• In § 1065.307(c)(7), change the text “instrument manufacturer 
recommendations” to “the instrument manufacturer’s recommendations,” add 
the text “ and to avoid hysteresis,” change the text “,  or as another example; 
you may select” to “or you may select,” change the text “reference signals, or 
as another example” to “reference signals; or,” and change the text “which 
might incorporate the effects” to  “to incorporate the effects.”  
• In §§ 1065.307(c)(10) and (11), change the text “the reference value” to  “the 
value at the reference condition.”  
• In § 1065.307(c)(11), change the text “ y̅i” to “y̅.” 
• In § 1065.307(c)(12), change the text “Repeat steps” to  “Repeat the steps,” 
and change the text “until all reference quantities are measured” to “until 
measurements are complete at each of the reference conditions.”  
• In § 1065.307(c)(13), change the text “Use the calculations described in 
§ 1065.602 described in § 1065.602” to “Use the calculations for a floating 
intercept described in § 1065.602.”  
• In § 1065.307(d), change the text “otherwise in other sections in this part” to  
“elsewhere in this part.”  
• In § 1065.307(d)(3), change the text “ Electrical power. Use a controlled source 
of current and a watt- hour standard reference meter. Complete calib ration 
systems that contain a current source and a reference watt -hour meter are 
commonly used in the electrical power distribution industry and are therefore 
commercially available”  to “Electrical power, current, and voltage. You must 
perform linearity verification for either electrical power meters, or for current 
and voltage meters. Perform linearity verifications using a reference meter and controlled sources of current and voltage. We recommend using a complete calibration system that is suitable for the electrical power distribution industry. ” 
• In § 1065.307(d)(5)(i), delete the requirement that flow meter calibration be done by the manufacturer.  
• In § 1065.307(d)(7), change the text “use a series of gas cylinders of known gas concentration” to “use a se ries of gas cylinders of known gas concentration 
containing only a single constituent of interest with balance of purified air or purified N
2.” 
• In §§ 1065.307(e)(3)(i) and (ii), change the text “refers to the typical mass of a 
PM filter” to  “is the typical  mass of a PM filter.  
• Add new paragraphs that define the maximum reference values for linearity 
verification for various instruments to subsection  1065.307(e)(3) as follows:  
348 1065.307(e)(3)(iii) for a fuel mass scale, 1065.307(e)(v) for a fuel flow rate met er, 
1065.307(e)(vii) for an intake- air flow rate meter, 1065.307(e)(viii) for a raw 
exhaust flow rate meter, 1065.307(e)(ix) for an electrical -power measurement 
system, 1065.307(e)(x) for an electrical -current measurement system, 
1065.307(e)(xi) for an electrical -voltage measurement system.  
• In § 1065.307(e)(5), change the text “These linearity verifications are optional 
for systems that pass the flow -rate verification for diluted exhaust as described 
in § 1065.341 (the propane check) or for systems that agree within ±2% based 
on a chemical balance of carbon or oxygen of th e intake air, fuel, and exhaust” 
to “Table 2 of this section describes optional verification procedures you may 
perform instead of linearity verification for certain systems. The following 
provisions apply for the alternative verification procedures .”  
• Add two new paragraphs to §  1065.307(e)(5), paragraph 1065.307(e)(5)(i) 
relating to propane check verification frequency and paragraph  1065.307(e)(5)(ii) relating to carbon balance error verif ication 
frequency.  
• In § 1065.307(e)(7)(i)(C), change the text “Dilution air for PM sampling” to  
“Dilution air for gaseous and PM sampling.”  
• In § 1065.307(e)(7)(i)(D), delete the text “if applicable.”  
• In paragraphs  1065.307(e)(7)(i)(E) and 1065.307(e)(8)(i) (E), change the text “ in 
the amount of water calculations in § 1065.645” to “in determining the amount 
of water r emoved from the emission sample.” Change the text “in lieu of the” 
to “instead of.” Change the text “We recommend that you input a reference 
simulated temperature signal below the alarm trip point, increase this signal 
until the high alarm trips, and verify that the alarm trip point value is no less 
than 2.0 °C below the reference value at the trip point” to  “To verify that the 
alarm trip point value is no less than 2.0 °C below the reference value at the trip 
point, we recommend that you input a reference simulated temperature signal 
below the alarm trip point and increase this signal until the high alarm trips. ” 
• Add two new paragraphs, 1065.307 (e)(7)(i)(F) with the text “Transmission oil” 
and 1065.307(e)(7)(i)(G) with the text “Axle gear oil,” as temperature signals requiring linearity verification.  
• In § 1065.307(e)(8)(i)(B), add the text “as required in § 1065.130(h) .” 
• In § 1065.307(e)(8)(i)(D) , add the text “where the raw exhaust enters the 
tunnel.”  
• Create a new subsection 1065.307(f) to contain the current Table 1 of § 1065.307 and make the following changes to Table 1: 
o Delete the “Minimum verification frequency” column in Table 1. 
o Add entries for “Current,” “Voltage,” and “Fuel mass scale.”   
349 o Add a new footnote (a) reference mark to “ Intake air flow rate ,” “Dilution 
air flow rate,” “ Diluted exhaust flow rate,” “ Raw exhaust flow rate ,” and 
“Batch sampler flow rate,” with the footnote text, “ For flow meters that 
determine volumetric flow rate, V ̇std, you may substitute V ̇std for ṅ as the 
quantity and substitute V ̇stdmax for ṅmax¬.” 
• Add a new subsection 1065.307(g) to contain the new Table 2 of §  1065.307, 
describing optional verification to linear ity verification for certain measurement 
systems.  
• In § 1065.308(d)(2), add the text “If you inject the gas at a tee near the outlet of 
the probe, you may correct the transformation time, t 50, for an estimate of the 
transport time from the probe inlet to th e tee.” Change the text, “probe 
sample flow rate,” and the text, “probe flow rate,” to  “sample flow rate.” Add 
the text “ We recommend you use the final, stabilized analyzer reading  as the 
final gas concentration.” Add the text “ The change in gas concentration must 
be at le ast 20% of the analyzer's range.”  
• In § 1065.308, add a new subsection 1065.308(g) with paragraphs (g)(1) through 
(g)(4), describing an optional procedure to use a fast -acting two -way valve to 
switch between zero and span gases, and listing  provisions required for such a 
procedure.  
• In § 1065.309(d)(2):  
o Add the text “If you inject the gas at a tee near the outlet of the probe, you may correct the transformation time, t
50, for an estimate of the 
transport time from the probe inlet to the tee. ”  
o Change the text “probe sample flow rate,” and the text, “probe flow 
rate,” to “sample flow rate.”  
o Add the text “ We recommend you use the final, stabilized analyzer 
reading  as the final gas concentration.”  
o Add the text, “ The change in gas concentration must be at le ast 20% of 
the analyzer's range.”  
o Change the text “purified synthetic air” to  “purified air.”  
o Change the text “ If your system does not use a sample dryer to remove 
water from the sample gas, you must humidify your span gas to the 
highest sam ple H 2O content that you estimate during emission sampling . 
If your system uses a  sample dryer during testing, it must pass the 
sample dryer verification check in § 1065.342” to “If the sample does not 
pass through a dryer during emission testing, humidify  your span gas to 
an H 2O level at or above the maximum expected during emission testing. 
If the sample does not pass through a dryer during emission t esting, it 
must pass the sample dryer verification check in § 1065.342 .”   
350 • Add a new subsection 1065.309(g) , stating that the optional procedures 
described in § 1065.308(g) may be used and that ambient air may be mixed 
with compensating gases for oxygen analyzers.  
• Add new subsections 1065.309(h), with paragraphs 1065.309(h)(1) and 
1065.3 09(h)(2), describing conditions under which span gas humidification may 
be omitted for analyzers with H 2O compensation sampling downstream of a 
sample dryer.  
• In § 1065.310(b), change the text “Recommended procedure” to 
“Recommended procedure  to quantify lever- arm length. Quantify  the lever -arm 
length, SI -traceable within ±0.5% uncertainty. The lever arm's length must be 
measured from the centerline of the dynamometer to the point at which the reference force is measured. The lever arm must be perpendicular to gravity 
(i.e., horizo ntal), and it must be perpendicular to the dynamometer's rotational 
axis. Balance the lever arm's torque or quantify its net hanging torque, SI-traceable within ±1% uncertainty, and account for it as part of the reference 
torque.”  
• Delete subsections 1065. 310(b)(1) and 1065.310(b)(2).  
• At the beginning of § 1065.310(c), add the text “ Recommended procedure to 
quantify reference force. We recommend dead -weight calibration, but you may 
use either of the following procedures to quantify the reference force, SI-traceable within ±0.5% uncertainty. ” 
• Move the currently adopted text of paragraph  1065.310(c), relating to dead 
weight calibration, to  a new paragraph  1065.310(c)(1); replace the instructions 
relating to local gravitational acceleration with a reference to 1065.630; delete the weight’s reference force specified, and the text “using this equation: torque – force – lever arm length.”  
• Change the lettering of paragraph 1065.310(d) , relating to strain gage or proving ring calibration, to paragraph 1065.310(c)(2 ), so that it is identified as 
one of the two procedures allowed under 1065.310(c). Add text to specify that 
1065.3 10(d) [re- lettered to 1065.310(c)(2)] also applies to load transducer 
calibration.  
• Delete the current text of § 1065.320(b) and add the text  “[Reserved].” 
• In paragraph 1065.340(b), add the text “ except as allowed i n paragraph (c) of 
this section.”  
• Change the lettering of paragraph 1065.340(c) to § 1065.340(d).  
• Add a new subsection 1065.340(c), allowing CFV or FFV flow meters to be 
removed from their permanent positions for calibration if certain conditions are met. 
• Change the lettering of subsection 1065.340(d) to 1065.340(e). Change the text 
“Do not use an upstream screen” to  “Calibrate the system with any upstream  
351 screens or other restrictio ns that will be used during testing and that could 
affect the flow ahead of the CVS flow meter, taking appropriate measures to 
minimize the effect on the flow distribution. You may not use any upstream 
screen.” Add the text “ In the case of a free standing SSV reference flow meter, 
you ma y not have any upstream screens.”  
• Change the lettering of subsection 1065.340(e) to  § 1065.340(f).  
• In § 1065.340(e)(8) [re- lettered to § 1065.340(f)(8)], change the text “t he 
minimum expected pressure at the PDP inlet ” to “the minimum expected 
pressure at the PDP inlet or the maximum expected differential (outlet minus inlet) pressure across the PDP during testing.” See also the proposed California -
specific changes described in the purpose and rationale for § 1065.340(f)(8) 
provided later in this section  G.  
• In § 1065.340(e)(13)  [re-lettered to § 1065.340(f)(13)], change the text, “ Do not 
use the PDP below the lowest inlet pressure tested during calibration” to 
“During emission testing ensure that the PDP is not operated either below the 
lowest inlet pressure point or above the highest differential pressure point in the calibration data. ” 
• Move § 1065.340(f) in the current regulation to a new location and re- letter it to 
§ 1065.340(h). Change the text “at the lowest expected static differential 
pressure between the CFV inlet and outlet ” to “up to the highest expected 
pressure ratio, r, according to § 1065.640.” Add a new paragraph as paragraph 
1065.3 40(h)(2), with the text, “Verify that any leaks between the calibration flow 
meter and the CFV are less than 0.3% of the total flow at the highest 
restriction. ” Re-letter paragraphs  1065.340(f)(2) and 1065.340(f)(3) to 
§ 1065.340(h)(3) and 1065.340(h)(4), respectively. Delete the current 
§ 1065.340(f)(4), “Leaks between the calibration flow meter and the CFV must 
be less than 0.3 % of the total flow at the highest restriction. ” 
• Move § 1065.340(g), containing instructions for calibrating a subsonic venturi (SSV) , to before the section describing critical -flow venturi calibration.  
• Change the lettering of subsection 1065.340(h) to 1065.340(i).  
• In paragraphs 1065.340(f)(9) and 1065.340(f)(10) [re- lettered to paragraphs 
1065.3 40(f)(9) and 1065.340(f)(10) in the Proposed Amendments], change 
references to lowest allowable pressure ratios to  references to highest 
allowable pressure ratios.  
• In the title of § 1065.341, change the text “CVS and batch sampler verification” 
to “CVS and PFD flow verification.”  
• In § 1065.341, add the following unnumbered paragraph to the beginning of 
the section as follows: “This section describes two optional methods, using 
propane as a tracer gas, to verify CVS and PFD flow streams. You may use good 
engineering judgment and safe practices to use other tracer gases, such as CO2 or CO. The first method, described in paragraphs (a) through (e) of this section,  
352 applies for the CVS diluted exhaust flow measurement system. It may also apply 
for other single- flow measurement systems as described in Table 2 of 
§1065.307. Paragraph (g) of this section describes a second method you may use to verify flow measurements in a PFD for determining the PFD dilution ratio.”  
• Delete subsection 1065.341(a) and change the lettering of paragraph 1065.3 41(b) to 1065.341(a).  
• Change the lettering of subsection 1065.341(c) to 1065.341(b). Add a provision allowing a prediluted propane tracer gas meeting certain specifications to be 
substituted for pure propane to subparagraph 1065.341(c)(1) (1065.341(b)(1) in 
the Proposed Amendments). In 1065.341(c)(3) (1065.341(b)(3) in the Proposed Amendments), change the text “where you introduce engine exhaust into the 
CVS” to “where you introduce engine exhaust into the CVS or at some point in 
the laboratory exhaust tubing upstream of this lo cation. ” In 1065.341(c)(5) 
(1065.341(b)(5) in the Proposed Amendments), change the text “precool” to  
“pre-cool.”  
• Change the lettering of subsections 1065.341(d), 1065.341(e), and 1065.341(f) to 1065.341(c), 1065.341(d), and 1065.341(e), respectively.  
• In § 1065.341(d) [1065.341(c) in the Proposed Amendments], change the 
reference to 1065.520(g) to  1065.520(f).  
• In § 1065.341(f)(5) [1065.341(e)(5) in the Proposed Amendments], change the reference to 1065.341(a) to  1065.341(f).  
• Add a new subsection 1065.341(f), containing a table listing possible causes of 
failed propane checks and recommended corrective actions.  
• In § 1065.341(g), change the text “ You may repeat the propane check to verify 
a batch sampler, such as a PM secondary dilution system” to  “You may verify 
flow measurements in a PFD (usually dilution air and diluted exhaust streams) for determining the dilution ratio in the PFD using the following method:.” In subsidiary paragraphs (g)(1) through (g)(4), change references to “batch 
samplers,” to references to PFDs; change instructions to “repeat” to “perform” 
the procedure; and specify that the propane should be injected in the same exhaust stream that is being sampled.  
• In paragraph 1065.341(g)(4), change the allowable difference of calculated and 
reference mass from 5% to 2%. Change the text “the batch sampler passes” to  
“all PFD flow measurements for determining PFD dilution ratio pass.” Change 
the reference to subsection 1065.341(a) to reference subsection 1065.341(f). 
Add a statement that for PFDs sampling only for PM, the allowable difference is 5%. 
• Add a new paragraph 1065.341(h) referring to alternatives to propane checks for linearity verification.   
353 • In § 1065.342(d)(2), change the text “Humidify room air, N 2, or purified air by 
bubbling it throu gh distilled water in a sealed vessel that humidifies the gas” to  
“Humidify room air, purified N 2, or purified air by bubbling it through distilled 
H2O in a sealed vessel  or use a device that injects distilled H 2O as vapor into a 
controlled gas flow to hum idify the gas .” 
• In paragraph 1065.345(d)(2), change the text “Supply span gas to the analyzer 
port and verify that it measures the span gas concentration within its expected 
measurement accuracy and repeatability” to  “Supply span gas to the analyzer  
span port and record the measured value. ” 
• In paragraph 1065.345(d)(4), change the text “ within ± 0.5%  of the span gas 
concentration” to “within ± 0.5% of the concentration measured in paragraph 
(d)(2) of this section.”  
• In § 1065.360(a)(3), add the text “ If you d etermine NMNEHC by subtracting 
from measured THC, determine the ethane (C 2H6) response factor after initial 
analyzer installation and after major maintenance as described in paragraph (f) of this section .” Change the text “methane (CH
4) response” to  “C 2H6.” 
• Add a new subsection 1065.360(a)(4) to provide instructions for determining 
methane and ethane response factors for gaseous- fueled engines.  
• In paragraph 1065.360(d)(7), change the text “ Introduce at the sample port of 
the FID analyzer, the CH 4 span gas that you selected under p aragraph (d)(2) of 
this section” to  “Introduce the CH 4 span gas that you selected under paragraph 
(d)(2) of this section into the FID analyzer. ” 
• Renumber paragraph 1065.360(d)(10) to 1065.360(d)(11).  
• Add a new paragraph 1 065.360(d)(10), stating that the procedure in paragraph 
(d) only needs to be performed for one range of the analyzer.  
• Add a new paragraph 1065.360(d)(12), describing the process of determining 
the response factor as a function of molar water concentration.  
• Delete § 1065.360(e), containing prior instructions for THC FID Ch 4 response 
verification, and its subsidiary paragraphs (1 -3).  
• Add a new subsection 1065.360(e) containing new instructions for THC FID CH 4 
response verification with subsidiary paragraphs (1 -5). 
• Add a new paragraph 1065.362(d)(15), stating that the procedure in subsection d only needs to be performed for one range of the analyzer.  
• In § 1065.365(d), add a statement that the method described in that subsection 
is required for gaseous- fueled engines, and add instructions for determining 
penetration fractions and response factors as a function of molar water 
concentration.  
• In § 1065.365(d)(1), add the text “ For CH
4 analyzers with multiple ranges, 
perform this procedure on the highest range used for emission testing.”   
354 • In § 1065.365(d)(9), change the text “this combined response factor and 
penetration fraction” to  “this combined C 2H6 response factor and C 2H6 
penetration fraction.” Change the reference to 1065.660(c)(1)(i) to refer to 1065.6 60(d)(1) (i). 
• In § 1065.365(d), add new subsections as 1065.365(d)(10), (d)(11), and (d)(12), 
which provide instructions for determining NMC FID methane penetration fraction and ethane response factors as a function of exhaust molar water content when measuring emissions from a gaseous fueled engine to account for the effect water has on nonmethane cutters.  
• In § 1065.365(e)(1), change the text “ or equal t o the THC analyzer's span value” 
to “and the C
2H6 concentration typical of the peak total hydrocarbon (THC) 
conce ntration expected at the hydrocarbon standard or equal to the THC 
analyzer's span value. For CH 4 analyzers with multiple ranges, perform this 
procedure on the highest range used for emission testing. ” 
• In § 1065.365(e)(10), change the reference to 1065.660( c)(1)(ii) to refer to 
1065.6 60(d)(1)(ii).  
• In § 1065.365(f)(1), add the text “ For CH 4 analyzers with multiple ranges, 
perform this procedure on the highest range used for emission testing.”  
• In § 1065.365(f)( 9), change the text “this combined response factor and 
penetration fraction” to  “this combined C 2H6 response factor and C 2H6 
penetration fraction.” Change the reference to 1065.660(c)(1)(i) to 1065.6 60(d)(1)(i).  
• In § 1065.365(f)( 14), change the text “this penetration fraction” to  “this CH
4 
penetration fraction,” and change the reference to 1065.660(c)(1)(iii) to  
1065.6 60(d)(1)(iii).  
• Add a new section 1065.366, regarding interference verification for FTIR analyzers.  
• Add a new secti on 1065.369, regarding interference verification for 
photoacoustic alcohol analyzers.  
• In § 1065.370(d)(9), add the option to determine CO
2 concentration from the 
gas divider output by measuring it using NDIR.  
• In § 1065.370(e)(5), change the text “Humidify the NO span gas by bubbling it,” 
to “Create a humidified NO span gas by bubbling a NO gas that meets the 
specifications in §1065.750 .” (Other changes in this paragraph are described in 
the “Updates to Harmonize with Amended Federal Text” subsection in this 
section  E). 
• In § 1065.375(d)(9), add the parenthetical text “ (the arithmetic mean of 
30 second data described in paragraph (d)(7) of this section).” Change the text 
“the tolerance specified” to “the tolerance for combined interference as 
specified.”   
355 • In § 1065.378(d)(3)(iv), change the text “20 percent of x NOref” to “20 percent of 
xNOref or a value which would simulate the maximum concentration of 
NO 2 expected during testing.” Add th e text “This ensures that the ozonator is 
generating NO2 at the maximum con centration expected during testing .”  
• In § 1065.390(b), add the text “Balances have internal weights that compensate 
for drift due to environmental changes. These internal weights must be verified 
as part of this independent verification with external, certified calibration 
weights that meet the specifications in §1065.790 .”  
• In § 1065.390(c), change the text “at least one calibration weight, and any 
weights you use must that meet the specifications in § 1065.790 to perform this 
verification” to “at leas t one calibration weight . Also, any external weights you 
use must meet the specifications in § 1065.790. Any weights internal to the PM 
balance used for this verification must be verified as described in paragraph (b) 
of this section.”  
• In § 1065.390(c)(2),  change  the text “internal calibration weights that are used 
automatically to verify balance performance” to  “internal weights for 
automatically verifying balance performance .” 
Harmonization Updates: Subpart E – Engine Selection, Preparation, and 
Maintenance  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  E: 
• In § 1065.405(a), add the text “consistent with paragraph (f) of this section.” 
Add the text “ If your engine is equipped with multiple user -selectable govern or 
types and if the governor does not manipulate the emission control system (i.e., the governor only modulates an “operator demand” signal such as 
commanded fuel rate, torque, or power), choose the governor type that allows the test cell to most accurately follow the duty cycle. If the governor manipulates the emission control system, treat it as an adjustable parameter. See paragraph (b) of this section for guidance on setting adjustable parameters.” Add the text “In certain circumstances, you may incorporate test 
cell components to simulate an in- use configuration. For example, §§1065.122 
and 1065.125 allow the use of test cell components to represent engine cooling 
and intake air systems. The provisions in §1065.110(e) also apply to emission- data engines for certification.”  
• Add a new paragraph 1065.405(b) as follows: “We may set adjustable parameters to any value in the valid range, and you are responsible for controlling emissions over the full valid range. For each adjustable parameter, if the standard -setting part has no unique requirements and if we have not 
specified a value, use good engineering judgment to select the most common 
setting. If information on the most common setting is not available, select the 
setting representing the engine's origina l shipped configuration. If information  
356 on the most common and original settings is not available, set the adjustable 
parameter in the middle of the valid range.”  
• Change the lettering of subsections 1065.405(b), 1065.405(c), 1065.405(d), and 
1065.4 05(e) to 1065.405(c), 1065.405(d), 1065.405(e), and 1065.405(f), 
respectively.  
• In § 1065.405(e)(2) [now re- lettered to (f)(2)], change the sentence “Use a 
canister that is fully loaded with fuel vapors. ” to “Precondition the canister as 
described in 40 CFR 86.132- 96(j).”  
• Add a new § 1065.405(g) to define the components that are considered to be 
part of the engine for laboratory testing.  
• In § 1065.410(c), change the text “Keep a record of the inspection and update your application to document any changes as a resu lt of the inspection. You 
may use equipment, instruments, or engineering grade tools to identify bad engine components. Any equipment, instruments, or tools used for scheduled 
maintenance on emission data engines must be representative of what is 
planned t o be available to dealers hips and other service outlets” to  “If you 
inspect an engine, keep a record of the inspection and update your application 
to document any changes that result. You may use any kind of equipment, 
instrument, or tool that is available  at dealerships and other service outlets to 
identify bad engine co mponents or perform maintenance.”  
• In § 1065.410(d), add the text “ You may repair defective parts from a test 
engine if they are unrelated to emission control. You must ask us to approve repairs that might affect the engine’s emission controls.”  
Harmonization Updates: Subpart F – Performing an Emission Test Over 
Specified Duty Cycles  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  F: 
• Change the Subpart F title from “ Performing an Emission Test in the 
Laboratory ” to “Performing an Emission Test Over Specified Duty Cycles .” 
• Change the lettering of subsections 1065.501(b), 1065.501(c), and 1065.501(d) to 1065.501(c), 1065.501(d), and 1065.501(e), respectively. Add a new 
paragraph 1065.501(b) as described in the purpose and rationale for 1065.5 01(b) provided later in this section G. 
• In paragraph 1065.501(b)(2)(i) [re -lettered to 1065.501(c)(2)(i) in the Proposed 
Amendments], change the text “Before emission sampling, stabilize an engine at the first discrete mode. Sample emissions and other parameters for that mode in the same manner as a transient cycle, with the exception that reference speed and torque values are constant. Record mean values for tha t mode, and 
then stabilize the engine at the next mode. Continue to sample each mode 
discretely as separate test intervals and calculate weighted emission results  
357 according to the standard -setting part” to  “Before emission sampling, stabilize 
an engine at the first discrete mode of the duty cycle specified in the 
standard -setting part.  Sample emissions and other parameters for that mode in 
the same manner as a transient cycle, with the exception that reference speed and torque values are constant. Record da ta for that mode, transition to the 
next mode, and then stabilize the engine at the next mode. Continue to sample 
each mode discretely as a separate test interval and calculate composite 
brake -specific emission results according to § 1065.650(g)(2).”  
• Add t hree new paragraphs to § 1065.501(c)(2)(i), paragraph (c)(2)(i)(A) relating 
to determination of the time required to stabilize the engine, paragraph  (c)(2)(i)(B) relating to PM sampling, and paragraph (c)(2)(i)(C) relating 
to minimum sampling intervals.  
• In paragraph 1065.510(b)(5)(i), delete the parenthetical text “(i.e., discrete 
mode or ramped modal)” and add the text “Record the mean speed and torque at each setpoint.”  
• Change the numbering of paragraph 1065.510(b)(6) to 1065.510(b)(7). Add a new subsect ion 1065.510(b)(6) to describe methods to determine warm 
high-idle speed for engines with a high- speed governor subject to a transient 
testing cycle with reference speeds above 100%.  
• In § 1065.510(c)(2), add the text “ You may start the negative torque map at 
either the minimum or maximum speed from paragraph (b) of this section.”  
• Add three new paragraphs to § 1065.510(d)(5), paragraph (d)(5)(i) relating to 
engine mapping for constant speed engines subject only to steady state testing, paragraph  (c)(5)(ii) r elating to engine mapping for any constant speed 
engine, and paragraph  (c)(5)(iii) relating to engine mapping for isochronous 
governed constant speed engines.  
• In § 1065.510(f)(5), move the text “For constant -speed engines you may declare 
a maximum test torque. You may use the declared value for cycle generation if 
it is within (95  to 100)% of the measured value” to a new paragraph 
1065.510 (f)(5)(ii). Add a new paragraph 1065.510(f)(i), “ For variable -speed 
engines you may declare a maximum torque over the engine operating range. 
You may use the declared value for measuring warm high- idle spe ed as 
specified in this section,”  
• Change the lettering of paragraph 1065.510(g) to 1065.510(h). Add a new 
paragraph 1065.510(g) with the text “[Reserved].” The new federal 1065.510(g) text is omitted because it relates to engines beyond the scope of the SORE 
category. See the Global Amendments subsection, “Changes to References of 
Equipment Types, Engine Types, and Fuel ,” for additional explanation.  
• In § 1065.512(b)(1),  add the text “ You may do either of the following when 
using enhanced -idle devices:”, and delete the text,  “and we recommend 
controlling .” Move the text “the dynamometer so it gives priority to follow the  
358 reference torque, controlling the operator demand so it gives priority to follow 
reference speed and let the engine govern the speed when the operator 
demand is at minimum” to a new paragraph 1065.512(b)(1)(i) with the text 
“Control” added at the beginning of the new paragraph. Add a new paragraph 1065.512(b)(1)(ii), stating that the ECM broadcast speed may be used as the reference speed in certain cases added.  
• In § 1065.512(b)(2), delete the text “. This provision” and add “, which” as indicated in strikeout and underline in the following: “Section 1065.610 also describes under what conditions you may command T
ref greater than the 
reference torque you calculated from a normalized duty cycle . This provision , 
which  permits you to command T ref values that are limited by a declared 
minimum torque.  
• In § 1065.514(e), change the text “calculate regression statistics as described” to “calculate regression statistics for a floating intercept as described.” Change 
“Table  2 of §  1065.514” to “Table 2 of this section.”  
• In § 1065.514(e)(3), change the text “Standard esti mates of error” to “Standard 
error of the estimate.”  
• In § 1065.514(f)(3), change  the text “paragraph (f)(1) or (2)” to  “paragraph  (f)(1) 
or (f)(2), “ and add the text “Note that if the gaseous and particulate test 
intervals are different periods of time, separate validations are required for the gaseous and particulate test intervals. Table 2 follows:.”  
• Add a new section  1065.516 to describe how to manage the impact of 
sampling system contamination on emission measurements, along with a 
recommended procedure  for how to precondition or decontaminate sampling 
systems.  
• In § 1065.520(a), change the text “ If your engine must comply with a PM 
standard ” to “For tests in which you measure PM emissions.”  
• Delete § 1065.520(f) and its subsidiary paragraphs.  
• Change the numbering of subsection 1065.520(g) to 1065.520(f). Change the 
text “nonmethane contamination” to  “nonmethane hydrocarbon 
contamination.” Add the text “ or for any CH
4 measurement system that uses an 
NMC .” Change the text “for this verification, however you  may measure”  to 
“for this verification; however, you may measure.” Change the text “sample 
train” to “sample path.” Change the text “ subtracting CH 4 from THC” to 
“subtracting CH 4 from THC or, where CH 4 is determined.” Change the text 
“and the calculations in § 1065.660(b)(2) ” to “and using the calculations in 
§ 1065.660(b)(2) .” 
• In § 1065.520(g)(5)(i) [re- lettered to 1065.520(f)(5)(i) in the Proposed 
Amendments], change the text “zero air flows” to “zero gas flows.”   
359 • Change the lettering of paragraphs 1065.520(g)(7) and 1065.520(g)(8) to 
1065.5 20(f)(8) and 1065.520(f)(9), respectively. In subparagraphs 
1065.5 20(g)(7)(i) and  (ii) [re -lettered to 1065.520(f)(8)(i) and (ii) in the Proposed 
Amendments], change the text “mean wet, net concentration” to  “mean  
concentration.”  
• Add a new subsection 1065.520(f)(7) to describe the manner in which THC initial 
concentration may be corrected for drift.  
• In the § 1065.525 title, delete the text “, and optional repeating of void discrete 
modes .” 
• In § 1065.525(a), change the text “Start the engine” to “For test intervals that 
require emission sampling during engine starting, start  the engine.”  
• Delete paragraph 1065.525(c)(4), relating to engine stalls.  
• In § 1065.526(a), change the text “instrument malfunctions” to “instru ment 
malfunction” and change the text “instrument ranges” to “instrument ranges , 
and other unexpected deviations from the specified procedures.”  
• In paragraph 1065.526(c)(2), change the text “test sequence” to “duty cycle .” 
• In paragraph 1065.526(c)(3), change the text “Precondition the engine” to  
“Stabilize the engine,” and change the text “ previous mode for approximately 
the same amount of time it operated at that mode for th e previous emission 
measurement” to “mode at which  the duty cycle was interrupted and continue 
with the duty cycle as specifi ed in the standard -setting part.”  
• Change the lettering of subsections 1065.526(d) and 1065.526(e) to 
1065.5 26(e) and 1065.526(f), respectively. Add a new subsection 1065.526(d), 
describing the manner in which results for an individual mode may be voided 
and repeated.  
• In § 1065.526(d)(1) [re- lettered to 1065.526(e)(1) in the Proposed Amendments], 
change the text “precondition the engine and emission sampling system” to  
“precondition the engine.”  
• In § 1065.526(e) [re- lettered to 1065.526(f) in the Proposed Amendments), 
delete the text “and include a description of the reason for voiding  the test 
mode or test interval.”  
• In § 1065.530(a)(1), change the text “ precondition sampling systems  as 
described in § 1065.520(f) ” to “precondition the engine as described in 
§ 1065.518.”  
• In § 1065.530(a)(1)(ii), change the text “shut down the engine. Start the 
hot-start duty cycle as specified in the standard -setting part” to “shut down the 
engine  imme diately after completing the last preconditioning cycle. For any 
repeat cycles, start the hot- start transient emission test within 60 seconds after  
360 completing the last preconditioning cycle (this is opt ional for manufacturer 
testing).”  
• In § 1065.530(a)(1)( iii), change the text “such as any steady state testing, you 
may continue to operate the engine at maximum test speed and 100% torque if 
that is the first operating point. Otherwise, operate the engine at warm idle or the first operating point of the duty cycle. In any case, start the emission test within 10 min after you complete the preconditioning procedure” to “such as 
any steady -state testing with a ramped -modal cycle, start the hot-stabilized 
emission test within 60 seconds after completing the last p reconditioning cycle 
(the time between cycles is optional for manufacturer testing). If the hot-stabilized cycle begins and ends with different operating conditions, add a 
linear transition period of 20 seconds between hot -stabilized cycles where you 
linea rly ramp the (denormalized) reference speed and torque values over the 
transition period. See § 1065.501(c)(2)(i) for discrete- mode c ycles.”  
• In § 1065.530(a)(2), change the text “precondition sampling systems” to  
“precondition the engine as described in §1 065.518.”  
• In paragraph 1065.530(a)(2)(iii), add instructions on how to determine that the engine temperature has stabilized for air cooled engines. Change the text  “as 
the point at which the engine coolant, block, or head absolute temperature is within ±2%  of its mean value for at least 2 min, or as the point at which the 
engine thermostat controls engine temperature” to “as the point at which the 
engine thermostat controls engine temperature or as the point at which the engine coolant, block, or head absolute temperature is within ±2% of its mean 
value for at least 2 min  based on the following parameters.” Add three new 
paragraphs 1065.530(a)(2)(iii)(A), 1065.530(a)(2)(iii)(B), and 1065.530(a)(2)(iii)(C), 
listing temperatures that may be referenced.  
• Delete paragraph 1065.530(b)(12), relating to starting the measurement of 
background concentrations, and paragraph 1065.530(b)(13), containing previous instructions regarding closing drains. Add a new paragraph 1065.5 30(530(b)(12), containing current instructions regarding closing drains.  
• Delete subsection 1065.530(c)  and its subsidiary paragraphs and add amended 
text containing instructions for starting and running each test interval. (The Proposed Amendments include California -specific changes to the federa l text, 
as described in the purpose/rational section for § 1065.530(c) provided later in 
this section  G). 
• Add a new paragraph 1065.530(g)(5), describing carbon balance error verification if it is performed as part of the test sequence.  
• In § 1065.545(a), change the text “ For any pair of flow meters rates, use 
recorded sample and total flow rates, where total flow rate means the raw exhaust flow rate for raw exhaust sampling and the dilute exhaust flow rate for CVS sampling, or their 1 Hz means, with th e stat istical calculations in 
§ 1065.602.” to “For any pair of flow rates, use recorded sample and total flow  
361 rates. Total flow rate means the raw exhaust flow rate for raw exhaust sampling 
and the dilute exhaust flow rate for CVS sampling, or their 1 Hz means w ith the 
statistical calculations in § 1065.602 forcing the intercept through zero.”  
• In § 1065.545(b), change the text “ For any pair of flow meters, use recorded 
sample and total flow rates, where total flow rate means the raw exhaust flow rate for raw exha ust sampling and the dilute exhaust flow rate for CVS 
sampling, or their 1 Hz means, to demonstrate that each flow rate was constant 
within ±2.5% of its resp ective mean or target flow rate.” to  “For any pair of 
flow rates, use recorded sample and total flo w rates. Total flow rate means the 
raw exhaust flow rate for raw exhaust sampling and the dilute exhaust flow rate 
for CVS sampling, or their 1 Hz means to demonstrate that each flow rate was constant within ±2.5% of its respective mean or target flow rate .” 
• In § 1065.545(c), change the text “total dilute exhaust (CVS) flow” to “total 
flow.”  
• In § 1065.546(a), change the capitalization of the text “Raw exhaust flow” to  
“raw exhaust flow.” Change the text “You may determine the raw exhaust flow rate based on the measured intake air  molar flow rate  and the  chemical balance 
terms as given in § 1065.655(f) ” to “You may determine the raw exhaust flow 
rate based on the measured intake air or fuel flow rate and the raw exhaust  
chemical balance terms as given in § 1065.655(f).” Add the text “ You may 
determine the raw exhaust flow rate based on the measured intake air and 
dilute exhaust molar flow rates and the dilute exhaust chemical balance terms 
as given in § 1065.655(g).”  
• Delete subsection 1065.550(b) and add a new  subsection 1065.550(b), 
containing amended instructions for drift validation.  
• In § 1065.590(f)(2), delete the text “For manual weighing.”  
• In § 1065.590(j)(3), change the text “Select a substitution weight” to  “Select 
and weigh a substitution weight.”  
• In paragraphs 1065.590(j)(4), 1065.590(j)(6), and 1065.590(j)(7), change the text 
“calibration weight” to  “substitution weight.”  
Harmonization Updates: Subpart G – Calculations and Data 
Requirements:  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  G: 
• In § 1065.601(b), change the text “You may not use test results from multiple 
emission tests” to  “Although you may use an average of multiple 
measurements from a single test, you may not use test results from multiple emission tests.”  
• In § 1065.601(b), move the following two sentences from the end of 
paragraph  (b) to two new subsections numbered (1) and (2): “We allow  
362 weighted means where appropriate. You may discard statistical outliers, but you 
must report all re sults.” Add a new paragraph 1065.601(b)(3) relating to 
provisions for when manufacturers may be allowed to exclude certain durability test data  relative to compliance with emission standards .  
• In § 1065.602(f)(3), delete the period at the end of the last sentence and add 
the text “, which follows:.”  
• In § 1065.602(g)(1), change the text “Table 2 of this section” to  “the following 
table.”  
• In 1065.602(g)(2), change the text “Table 3 of this section” to  “the following 
table.” Move Table 2 so that it follows § 1 065.602(g)(1) rather than following 
§ 1065.602(g)(2).  
• In § 1065.602(h), change the text “as follows” to  “using one of the following 
two methods.” Move the equations attached to paragraph 1065.602(h) to a new paragraph 1065.602(h)(1) and add the text “If the intercept floats, i.e., is not forced through zero:” to the beginning of the new paragraph. Add a new paragraph 1065.602(h)(2), addressing equations to be used if the intercept is forced through zero.  
• In § 1065.602(j), change the text “Standard estimate of error” to  “Standard 
error of the estimate.” Move the equations attached to paragraph 1065.602(h) to a new paragraph 1065.602(j)(1) and add the text “For a floating intercept” to the beginning of the new paragraph. Add a new paragraph 1065.602(j)(2), addressing equations to be used if the intercept is forced through zero.  
• In § 1065.602(k ), change the equation label from, ”Eq. 1065.602-1 2” to 
“Eq. 1065.602- 14.” 
• In § 1065.602(l )(2)(iii) , change the equation label from, ”Eq. 1065.602 -15” to 
“Eq. 1065.602 -17.” 
• In § 1065.610(a), change the text “determine the measured f
ntest from the 
power -versus- speed map, generated according to § 1065. 610, as follows ” to 
“determine f ntest as follows.” Delete subsection 1065.610(a)(1) and its subsidiary 
paragraphs and equation s, containing previous instructions for determining 
maximum power and the speed at which it occurs. Add a new subsection 1065.6 10(a)(1) containing instructions for determining f
ntest, maximum power, 
and the speed at which it occurs. Change the numbering of  
subsections  1065.610(a)( 2) and (a)(3) to 1065.610(a)(3) and (a)(4), respectively. 
Add a new subsection 1065.610(a)(2) containing instructions for determining 
fntest,alt , an alternate maximum power, and the speed at which it occurs, for 
engines with a high- speed governor that will be subject to a reference duty 
cycle that specifies normalized speeds greater than 100 percent .  
• Delete subsection 1065.610(b) and its subsidiary paragraphs and equations, containing previous instructions for determining maximum test torque. Add a  
363 new subsection 1065.610(b), containing current instructions for determining 
maximum test torque.  
• Delete subsection 1065.610(c) and its subsidiary paragraphs and equations, containing previous instructions for generating reference speed va lues from 
normalized duty cycles. Add a new subsection 1065.610(c), containing current instructions for generating reference speed values from normalized duty cycles.  
• In the title of §  1065.630, change the text “1980 international gravity formula” 
to “Loca l acceleration of gravity.”  
• Delete the current text of § 1065.630 and  its subsidiary equations, containing 
previous instructions for calculating local gravity based on location. Add two new subsections, 1065.630(a), containing a reference to the United Sta tes 
National Oceanographic and Atmospheric Administration’s surface gravity 
prediction web tool, and 1065.630(b), containing current instructions for 
calculating local gravity based on location.  
• Delete subsection 1065.640(b) and its subsidiary paragraphs ( b)(1) through 
(b)(4) and their associated equations, containing instructions for PDP calibration 
calculations. Add a new subsection 1065.640(b) with new paragraphs (b)(1) 
through (b)(4), containing current instructions for PDP calibration calculations.  
• In paragraph 1065.640(b)(6), change the text “corresponding slope, a
1, and 
intercept, a 0” to “the appropriate regression equation from this paragraph  (b).” 
• In subsection 1065.640(c):  
o Change the text “ In paragraph (c)( 4) of this section, we describe other 
assumptions that you may make, depending upon how you conduct your 
emission tests” to  “Paragraph (c)(5) of this section describes o ther 
assumptions that may apply.”  
o Delete the text  “If we do not allow you to assume that the measured 
flow is an ideal gas, the governing equations include a first -order 
correction for the behavior of a real gas; namely, the compressibility 
factor, Z.”  
o Move the equations associated with the initial paragraph and the text “Calculate molar flow rate,  ṅ, as follows ” to a new paragraph 
1065.6 40(c)(1).  
o Delete paragraph 1065.640(c)(4), containing previous guidance regarding 
simplifying assumptions. Renumber paragraphs 1065.640(c)(1), 
1065.6 40(c)(2), and 1065.640(c)(3), and 1065.640(c)(5) to  1065.640(c)(2), 
1065.6 40(c)(3), 1065.640(c)(4), and 1065.640(c)(6), respectively. Add a 
newly proposed paragraph 1065.640(c)(5), containing current guidance 
regarding simplifying assumptions.  
• In paragraph 1065.640(c)(1) [(1065.640(c)(2) in the Proposed Amendm ents], 
change the text “calculate C
d” to “calculate C d for each flow rate”   
364 • In paragraph 1065.640(c)(2)(ii) (1065.640(c)(3)(ii) in the Proposed Amendments), 
change the text “use the following equation to calculate C f” to “use the 
following equation to calculate C f for each flow rate .” 
• In paragraph 1065.640(c)(5) [renumbered to 1065.640(c)(6) in the Proposed 
Amendments], change the text “the discharge coefficient,  Cd” to “C d.” Change 
the text “ J/(mol·K) ” to “(m2 · kg)/(s2 · mol · K) .” Change the text “99132.0 Pa  to 
“99.132 kPa = 99132.0 Pa = 99132 kg/(m·s 2).” 
• In the first paragraph of §  1065.640(d)(1), change the text “reference molar flow 
rate, using” to  “reference molar flow rate, ṅ ref, using. ” Make the following 
changes t o text and formulas that follow the first paragraph:  
o Change the text “ Sutherland three -coefficient viscosity model ” to 
“Sutherland three- coefficient viscosity model as captured in Table 4 of 
this section.”  
o Change the text “ dT = 152.4 mm ” to “d T = 152.4 mm = 0.1524 m .”  
o Change the formula steps  
“ ” and “Re# = 7.541 ·105” to  
“ .” 
o In the example that follows Table 4 of §  1065.640, change 
“T0 = 273.11  K” to “T0 = 273 K,” change “ S = 110.56  K” to “S = 111 K,” 
and change “ Mmix = 28.7805 g/mol ” to “Mmix = 28.7805 g/ mol = 
0.0287805  kg/mol.” 
• In Table 4 of 1065.640, add a new footnote (b) reference mark to the headings 
of the “Temperature range within ± 2% error” and “Pressure limit” columns, 
and stating that the model results are valid only for ambient  conditions in the 
specified ranges.  
• In paragraph 1065.640(d)(2), change the text “Create an equation for C d versus 
Re#, using paired values of (Re#, C d). For the equation, you may use any 
mathematical expression, including a polynomial or a power series. The following equation is an example of a commonly used mathematical expression for relating C
d and Re#:” to “Create an equation for C d as a function of  Re#, 
using paired values of the two quantities. The equation may involve any mathematical expression, i ncluding a polynomial or a power series. The 
following equation is an example of a commonly used mathematical expression 
for relating  C
d and Re#:.” 
• In paragraph 1065.640(d)(3), change the text “ Perform a least- squares 
regression analysis to determine the best -fit coefficients  to the equation and 
calculate the equation's regression statistics, SEE and r2, according to 
 
365 § 1065.602” to “Perform a least -squares regression analysis to determine t he 
best-fit coefficients for the equation and calculate SEE as desc ribed in 
§ 1065.602.” Add the text “ When using Eq. 1065.640- 12, treat C d as y and the 
radical term as y ref and use Eq. 1065.602- 12 to calculate SEE. When using 
another mathematical expression, use the same approach to substitute that 
expression into the numerator of Eq. 1065.602- 12 and replace the 2 in the 
denominator with the number of coefficients  in the mathematical expression.”  
• In paragraph 1065.640(d)(4), change the text “If the equation meets the criteria of SEE ≤ 0.5% · n
refmax and r2 ≥ 0.995, you may use the equation to determine C d 
for emission tests, as described in § 1065.642” to  “If the equation meets the 
criterion of  SEE ≤ 0.5% ·  Cdmax, you may use the equation for the corresponding 
range of  Re#, as described in §1065.642. ” 
• In paragraph 1065.640(d)(5), change the text “ If the  SEE and r2 criteria are not 
met” to “equation does not meet the specified statistical criterion.” Change the 
text “ You must use at least seven calibration d ata points to meet the criteria” 
to “however , you must use a t least seven calibration data points to meet the 
criteria. ” Delete the text “to meet the regression statistics.” Add the text “ For 
example, this may involve narrowing the range of fl ow rates for a better curve 
fit.”  
• In paragraph 1065.640(d)(6), change the text “ If omitting points does not 
resolve outliers, t ake corrective action ” to “Take corrective action if the 
equation does not meet the specified statistical criterion even after omitting calibration data points.”  
• In paragraph 1065.640(d)(7), change the text “ only to determine flow rates that 
are within the range of the reference flow rates used to meet the C
d versus Re# 
equation's regression criteria” to “only for the corresponding range of Re#.” 
• In 1065.640(e), change the text “all of the venturis” to  “all the venturis.”  
• In 1065.640(e)(3), change the text “use the mean C d in Eq 1065.642 -6, and use 
the CFV only down to the lowest r ” to “use the mean C d in Eq  1065.642 -4, and 
use the CFV only  up to the highest venturi pressure ratio r .” 
• In 1065.640(e)(4), change the text “omit the C d values corresponding to the 
data point collected at the lowest r ” to “omit the C d value corresponding to the 
data point collected at the highest r .” 
• In 1065.640(e)(7), change the text “ use that mean C d in Eq 1065.642- 6, and use 
the CFV only down to the lowest r ” to “use that mean C d in Eq 1065.642- 4, and 
use the CFV only up to the highest venturi pressure ratio r.”  
• Delete subsection 1065.642(a), containing instructions for calculating the PDP 
molar flow rate, and add a new subsection 1065.642(a), containing amended 
instructions for calculating PDP molar flow rate.   
366 • In 1065.642(b), change the text “Based on the C d versus Re # equation you 
determined according to § 1065.640, c alculate SSV molar flow rate, n ̇ during an 
emission test as follows” to “Calculate SSV molar flow rate, ṅ as follows .” Add a 
list of symbols used in this subsection’s calculations and their meanings. Change 
the text “ pin = 99132 Pa ” to “pin = 9.132 kPa = 99132 Pa = 99132 kg/(m·s2).” 
• In 1065.642(c), change the text “you calibrated each venturi” to  “you calibrate 
each venturi.” Change the text “ Cd, for each venturi” to “C d (or calibration 
coefficient,  Kv), for each venturi.” Change the text “each combination of 
venturis” to “venturis in combination.” Change the text “ calculate ṅ as using ” 
to “calculate ṅ using .” Change the text “ all of the venturis ” to “all the venturis. ” 
Delete the text “To calculate the molar flow rate through one venturi or one 
combination of venturis , use its respective mean Cd and other constants you 
determined according to § 1065.640 and calculate its molar flow rate n during an emission test, as follows:.”  
• Move the equations associated with paragraph 1065.642(c) to a new 
subsection 1065.642(c)(1). Add the text “To calculate n ̇ through one venturi or 
one combination of venturis, use its respective mean C
d and other constants 
you determined according to §1065.640 and calculate n ̇ as follows: ” to the 
beginning of the new subsection. Add the text “Where: C f = flow coefficient, as 
determined in §1065.640(c)(3).” Change the text “ pin = 98836 Pa” to “ pin = 
98.836 kPa = 98836 Pa = 98836 kg/(m·s2).” 
• Add a new subsection 1065.642(c)(2), containing instructions for using the mean 
molar flow rate and other constants to calculate the molar flow rate through one venturi or combination of venturis.  
• In § 1065.644, change the text “Eq. 1065.644 -1” to “the following equation.” 
Change the text “ R = 8.314472 J/(  mol L·K)” to “R = 8.314472 J/(mol·K) = 
8.3144 72 (m
2 · kg)/(s2 · mol · K) .” Change the text “p 2 = 50.600 kPa = 50600 Pa” 
to “p2 = 50.600 kPa = 50600 Pa = 50600 kg/(m · s2).” Change the text “p 1 = 
25.300 kPa = 25300 Pa” to  “p1 = 25.300 kPa = 25300 Pa = 25300 kg/(m  · s2).” 
Change the text “AM” to “a.m..”  
• In § 1065.645, add the text “Paragraph (d) of this section provides an equation 
for determining dewpoint from relative humidity and dry bulb temperature measurements. The equations for the vapor pressure of water as presented in this section are derived from e quations in “Saturation Pressure of Water on the 
New Kelvin Temperature Scale” (Goff, J.A., Transactions American Society of Heating and Air -Conditioning Engineers, Vol.  63, No. 1607, pages 347- 354). 
Note that the equations were originally published to derive vapor pressure in units of atmospheres and have been modified to derive results in units of kPa by converting the last term in each equation. ” 
• Add a new subsection 1065.645(d), containing instructions for dewpoint determination from relative humidity and dry bulb temperature.   
367 • Renumber the currently adopted paragraphs 1065.650(c)(1)(i), 1065.650(c)(1)(ii), 
1065.650 (c)(1)(iii), 1065.650(c)(1)(iv), and 1065.650(c)(1)(v) to  1065.650(c)(1)(ii), 
1065.650 (c)(1)(iv), 1065.650(c)(1)(v), 1065.650(c)(1)(vi), and 1 065.645(c)(1)(vii), 
respectively. Add a new paragraph 1065.650(c)(1)(i), with the text “Use good 
engineering judgment to t ime-align flow and concentration data to match 
transformation time, t 50, to within ±1 s. ” Delete the same text from 
paragraph  1065.650(c)(1)(i) [renumbered to 1065.650(c)(1)(ii) in the Proposed 
Amendments]. Delete paragraph 1065.650(c)(1)(vi), relating to background 
correction of NMHC, and paragraph 1065.650(c)(1)(vii), relating to calculation of 
brake-specific emissions with regard to d rift.  
• In paragraph 1065.650(c)(1)(i) [renumbered to 1065.650(c)(1)(ii) in the Proposed Amendments], change the text “ Correct all THC and CH
4 concentrations, 
including continuous readings, sample bags readings, and dilution air 
background readings, for initial contamination, as described in § 1065.660(a) ” 
to “Correct all gaseous emission analyzer concentration readings, including 
continuous readings, sample bag readings, and dilution air background 
readings, for drift as described in §1065.672. Note that you must omit this step where brake specific emissions are calculated without the drift correction for 
performing the drift validation according to §1065.550(b). When applying the 
initial THC and CH4 contamination readings according to §1065.520(f), use the same values for both sets of calculations. You may also use as measured values in the initial set of calculations and corrected values in the drift corrected set of calculations as described in §1065.520(f)(7). ” 
• Add a new paragraph 1065.650(c)(1)(iii), wit h the text “ Correct all THC and CH
4 
concentrations, for initial contamination as described in §1065.660(a), including continuous readings, sample bags readings, and d ilution air background 
readings.”  
• In paragraph 1065.650(c)(1)(iii) [renumbered to 1065.65 0(c)(1)(v) in the 
Proposed Amendments], change the text “THC and NMHC” to  “NMHC and 
CH
4.” 
• Add a new paragraph 1065.650(c)(5), relating to comparison of the correct masses of NMHC and THC.  
• Add a new paragraph 1065.650(c)(6), relating to NMNEHC calculations for test fuels of specific ethane content.  
• In § 1065.650(d), change references to paragraphs “(b)(1) through (7)” and 
“(b)(8)” to “(d)(1) through (7)” and “(d)(8),” respectively. Change “ Note, that 
there must be two consecutive reference zero load idle points to establish a period where this applies. ” to “Note, that there must be two consecutive 
reference zero load idle points to establish a period where the zero -load 
exclusion applies. ” Change “meets these requirements using rectangular 
integration ” to “meets the requirements of this paragraph (d) using rectangular 
integration .”  
368 • In paragraph  1065.650(e)(2), change the text “Equation 1065.650- 13” to 
“Eq. 1065.650- 13.” 
• In paragraph 1065.650(f)(2), change the text “you may use the default values” 
to “you ma y use default values.” Change the text “as described in § 1065.655” 
to “as described in § 1065.655(e) .” 
• Add a new paragraph 1065.655(b)(2), with the text “Raw exhaust molar flow 
rate either from measured intake air molar flow rate or from fuel mass flow ra te 
as described in paragraph (f) of this section.”  
• In § 1065.655(b), renumber paragraphs 1065.655(b)(2) and 1065.655(b)(3) to  
1065.6 55(b)(4) and 1065.645(b)(5), respectively.  
• Add a new paragraph 1065.655(b)(3), with the text “Raw exhaust molar flow rate from measured intake air molar flow rate and dilute exhaust molar flow rate, as described in paragraph (g) of this section.”.  
• In 1065.655(b)(2) [renumbered to 1065.655(b)(4) in the Proposed Amendments], 
change the text “according to § 1065.659(c)(2)” to  “according to § 1065.659.”  
• In 1065.655(b)(3) [renumbered to 1065.655(b)(5) in the Proposed Amendments], 
change the text “ The flow-weighted mean fraction of dilution air in diluted 
exhaust, x
dil/exh, when you do not measure dilution air flow to correct for 
back ground emissions as described in § 1065.667(c) . Note that if you use 
chemical balances for this purpose, you are assuming that your exhaust is 
stoichiometric, even if it is not. ” to “The calculated total dilution air flow  when 
you do not measure dilution a ir flow to correct for background emissions as 
described in § 1065.667(c) and (d).”  
• In 1065.655(c)(3), change the text “ for this paragraph (c)” to  “for performing 
the chemical balance calculations in this paragraph (c).”  
• In 1065.655(c)(3), add the text “and any injected fluids” to the definition of 
xCcombdry  as indicated in underline in the following,  “amount of carbon from fuel 
and any injected fluids in the exhaust per mole of dry exhaust. ” 
• In 1065.655(c)(3), change the text “mixture of fuel(s) being combusted, 
weighted by molar consumption ” to “fuel (or mixture of test fuels) and any 
injected fluids” in each of the definitions of α, β, γ, and δ . 
• In 1065.655(c)(3), change the format of the list of “symbols and subscripts in the equations for performing  the chemical balance calculations in this 
paragraph  (c)” from a list format to a table titled “ Table 1 of §1065.655—
Symbols and Subscripts for Chemical Balance Equations.” Because the list of 
symbols and subscripts in federal Part 1065. 655(c)(3)  was extensively 
reformatted subsequent to CARB’s adoption of California’s Part 1065, the Proposed Amendments replace the entirety of the list  with a table  formatted to 
mirror the current organization of the federal Part 1065. 655(c)(3) .  
369 • In 1065.655(d), add “of fuel”  to the section title, “Carbon mass fraction of fuel,” 
and delete the text “using one of the following methods: .” Move the currently 
adopted text of subsection 1065.655(d)(1) to subsection 1065.655(d) and delete 
the text “You may calculate w c as described in this paragraph (d)(1) based on 
measured fuel properties. To do so, you must determine values for α  and β in all 
cases, but you may set γ  and δ to zero if the default value listed in Table 1 of 
this section is zero.” Change the text “mixture of fuel(s) being combusted, weighted by molar consumption ” to “fuel (or mixture of test fuels) and any 
injected fluids” in each of the definitions of α, β, γ, and δ . Other changes to this 
subsection are described in the Global Amendments subsection, “Changes to References of Equipment Types, Engine Types, and Fuel ,” provided earlier in 
this section  G. 
• Delete paragraph 1065.655(d)(2), with the text “You may use the default values in the following table to determine w
c for a given fuel: ”.  
• Change the lettering of subsection 1065.655(e) to 1065.655(f). Add a new subsection 1065.655(e), with California -specific changes to otherwise 
harmonized text as described in the purpose and rationale specific to § 1065.655(e) later in this section G.  
• Move Table 1 of 1065.655 to a new paragraph 1065.655(e)(5), with the text 
“Table 2 follows:.” In the table title, change “Table 1” to “Table  2.” Delete the 
text “ , for Various Fuels” from the table title. Add table rows for “E10 
Gasoline,” “E15 Gasoline,” and “E85 Gasoline.” Change T able 1 entries for 
“Ethanol” and “Methanol” to  “E100 Ethanol” and “M100 Methanol,” 
respectively, and move the entries to a higher position in the table so that they 
are in alpha -numeric order. Other changes are described in the Global 
Amendments subsection earlier in this section G, “Changes to References of 
Equipment Types, Engine Types, and Fuel .” 
• In paragraph 1065.655(e) [re- lettered to 1065.655(f) in Proposed Amendments], 
add the text “For laboratory tests, calculating raw exhaust molar flow rate using measured fuel mass flow rate is valid only for steady -state testing. See 
§ 1065.915(d)(5)(iv) f or application to field testing.”  
• In paragraph 1065.655(f)(2), change the text “Based on ṅ
int, calculate ṅ exh as 
follows” to “Calculate ṅexh based on ṅ int as fo llows.” Change the equation 
number from 1065.655- 20 to 1065.655- 24. 
• In paragraph 1065.655(f)(3), change the text “Fuel mass flow” to  “Fluid mass 
flow.” Add the text “ This calculation may be used only for steady -state 
laboratory testing. You may not use this calculation if the standard -setting part 
requires carbon balance error verification as described in §1065.543. See §1065.915(d)(5)(iv) for application to field testing.” Renumber Equation 
1065.655- 21 to Equation 1065.655- 25. Delete the text “ ṁ
fuel = fuel flow rate 
including humidity in intake air.” Add the following definitions:   
370 j = an indexing variable that represents one fuel or injected fluid, starting 
with j = 1. 
N = total number of fuels and injected fluids over the duty cycle.  
ṁj = the mass flow rate of the fuel or any injected fluid  j. 
WCj = carbon mass fraction of the fuel and any injected fluid j.  
Add the lines “N = 1” and “J = 1” to the beginning  of the example. Change the 
text “ṁfuel” to “ṁ1” in the example.  
• Add a new subsection 1065.655(g), containing instructions for calculation of raw 
exhaust molar flow.  
• In paragraph 1065.659(a), change the text “ If you remove water upstream of a 
concentration measurement, x, or upstream of a flow measurement, n, correct for the removed water. Perform this correction based on the amount of water at the concentration measurement, x
H2O[emission]meas , and at the flow meter, x H2Oexh , 
whose flow is used to determine the concentration's total mass over a test interval ” to “If you remove water upstream of a concentration measurement, x,  
correct for the removed water. Perform this correction based on the amount of water at the concentration measurement, x
H2O[emission]meas , and at the flow meter, 
xH2Oexh , who se flow is used to determine the mass emission rate or total mass  
over a test interval.” Add additional instructions for continuous analyzers downstream of a sample dryer for transient and ramped -modal cycles, and for 
batch analyzers.  
• Delete subsection 1065.659(b) and its subsidiary paragraphs, containing 
instructions for removed water calculations for certain types of analyzers. Add a 
new paragraph 1065.659(b), containing instructions relating to concentrations upstream and downstream of a sample dryer.  
• In paragraph 1065.659(c) , change the text “For a corresponding concentration 
or flow measurement where you did not remove water, you may determine the 
amount of initial water by any of the following” to  “For a concentration 
measurement where you did not remove water, you may set  x
H2O[emission]meas  equal 
to xH2Oexh . You may determine the amount of initial water at the flow meter, 
xH2Oexh , using any of the following methods.”  
• In paragraph 1065.659(c)(1), change the text “Use any of the techniques 
described i n paragraph (b) of this section” to  ”Measure the d ewpoint and 
absolute pressure and calculate the amount of water as described in 
§1065.645.”  
• Delete subsections 1065.660(a) containing instructions for THC determination and initial THC/CH
4 contamination corrections, 1065.660(b) containing 
instructions for  NMHC determination, and 1065.660(c) containing instructions 
for CH 4 determination. Add new subsections 1065.660(a), containing amended 
instructions for THC determination and initial THC/CH 4 contamination 
correction s, 1065.660(b) containing amended instructions for NMHC  
371 determination, 1065.660(c) containing instructions for NMNEHC determination, 
1065.660(d) containing amended instructions for CH 4 determination, and 
1065.660(e) containing instructions for C 2H6 determination.  
• In § 1065.665(a), change t he text “NOTHC” to “non -oxygenated total 
hydrocarbon (NOTHC).” Change the text “THCE” to  “total hydrocarbon 
equivalent (THCE).” Change the text “only required” to  “required only.” 
Change the text “OHC” to  “oxygenated hydrocarbon (OHC).” Change the text 
“xOHCi” in Eq. 1065.655- 2 to “(x OHCi - x OHCi -init).” Delete the text “C # = the mean 
number of carbon atoms in the particular compound.”  
• In § 1065.665(b), change the text “NMHCE” to  “nonmethane hydrocarbon 
equivalent (NMHCE).”  
• In § 1065.665(c), change the text “HCHO” to “CH 2O.” 
• In paragraph 1065.667(a), change the text “This may be a measured quantity or a quantity calculated from the diluted exhaust flow and the flow -weighted mean 
fraction of dilution air in diluted exhaust, x
dil/exh. Multiply the total flow  of 
dilution air by the mean concentration of a background emission” to  “This may 
be a measured quantity or a calculated quantity. Multiply the total flow of dilution air by the mean mole fraction (i.e., concentration) of a background 
emission.” Add the text “Finally, multiply by the molar mass, M, of the 
associat ed gaseous emission constituent.” Change the tex t “The product of n
dil 
and the mean concentration of a background emission is the total amount of a background emission. If this is a molar quantity,  convert it to a mass by 
multiplying it by its molar mass, M. The result is the mass of the background emission, m” to “The product of n
dil and the mean molar concentration of a 
background emission and its molar mass, M, is the total background emission mass, m.” Change the text “total background masses” to  “total background 
mass.”  
• In paragraph 1065.667(b), delete the text “ In this case, calculate the total mass 
of background as described in § 1065.650(c), using the dilution air flow, n
dil. 
Subtract the background mass from the total mass. Use the result in brake -specific emission calculati ons.”  
• In paragraph 1065.667(c), add the text indicated in underline, “ You may 
determine the total flow of dilution air b y subtracting the calculated raw 
exhaust molar flow  as described in §1065.655(g) from the measured dilute 
exhaust flow. This may be done by totaling continuous calculations or by using 
batch results .” Move the remainder of the text in paragraph 1065.667(c) to a 
new paragraph 1065.667(d).  
• Make the following  changes to the newly lettered paragraph 1065.667( d): 
o Change the text “ from the total flow of diluted exhaust and a chemical 
balance of the fuel, intake air, and exhaust as described in § 1065.655.” to “(d) You may determine the total flow of dilution air from the   
372 measured dilute exhaust flow and a chemical balance of the fuel, any 
injected fluids, intake air, and dilute exhaust as described in §1065.655.”  
o Change the text “In this case, calculate the total mass of background as 
described in § 1065.650(c), using the total flow of diluted exhaust, n dexh, 
then multiply this result by the flow -weighted mean fraction of dilution 
air in diluted gas to dilute exhaust,  xdil/exh, from  the dilute chemical 
balance” to “For this option, the molar flow of dilution air is calculated 
by multiplying the dilute exhaust flow by the mole fraction of dilution gas 
to dilute exhaust,  xdil/exh, from the dilute chemical balance .”  
o Add the text “This may be done by totaling continuous calculations or by 
using batch results. For example, to use batch results, the total flow of 
dilution air is calculated by multiplying the total flow of diluted 
exhaust,  ndexh, by the flow -weighted mean mole fraction of d ilution air in 
diluted exhaust,  x̅dil/exh.”  
o Change the text “You may assume that your engine operates 
stoichiometrically” to “The chemical balance in §1065.655 assumes that 
your engine operates stoichiometrically.”  
o Change the text “corrects excess air” to  “treats excess air.”  
o Change the text “ If this error might affect your ability to show that your 
engines comply with applicable standards , we recommend that you 
remove background emissions” to “If this error might affect your ability 
to show that your engines comply with applicable standards i n this 
chapter, we recommend that you either determine the total flow of 
dilution air using one of the more accurate methods in paragraph (b) or (c) of this  section, or remove background emissions.”  
o Other changes are as described in the Global Amendments subsection, 
“Changes to References of Equipment Types, Engine Types, and Fuel ,” 
earlier in this section G and in the purpose and rationale specific to 
“§ 1065.667(d)  [newly lettered paragraph]” provided later in this 
section  G. 
• Change the lettering of paragraphs 1065.667(d) and 1067.667(e) to  1065.667(e) 
and 1065.667(f), respectively.  
• In subsection 1065.670, change the text “first apply any NO
X corrections fo r 
background emissions and water removal from the exhaust sample, then 
correct NO X concentrations for intake -air humidity” to  “correct NO X 
concentrations for intake -air humidity as described in this section. See 
§1065.650(c)(1) for the proper sequence for applying the NO X intake -air 
humidity and temperature corrections .”  
• In subsection 1065.675(d), change several values of initial parameters, 
intermediate values in the calculation, and the example answers ar.   
373 • Add a new section  1065.680, providing  instructio ns for how to calculate and 
apply emission adjustment factors for engines using aftertreatment technology 
with infrequent regeneration events that may occur during testing . 
• In paragraph 1065.690(c), change the text “in the buoyancy correction 
equation” to “when determining the air density of the balance environment .” 
• Add a new paragraph 1065.695(c)(6)(x), with the text “Number and type of preconditioning cycles.”  
• Add a new paragraph 1065.695(c)(8)(v), with the text “Carbon balance error verification, if performed.”  
Harmonization Updates: Subpart H – E ngine Fluids, Test Fuels, Analytical 
Gases, and Other Calibration Standards  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  H: 
• Change the labelling of paragraph 1065.701(d) to  paragraph 1065.701(d)(2). 
Add a new subsection 1065.701(d) with the text “Fuel specifications. Specifications in this section apply as follows: .” Add a new paragraph 
1065.7 01(d)(1) describing measurement, ca lculation, and reporting of values for 
fuel specification purposes. Change the references in the second and third 
sentences of the newly numbered paragraph 1065.701(d)(2) from 40 CFR part 
80 and 80.46 to 40 CFR part 1090 and 1090.1360, respectively.  
• In Tab le 1 of 1065.750, change the footnote labels from 1 and 2 to  a and b, 
respectively. Delete the footnote 1 reference mark from the column headings “Purified synthetic air” and “Purified N
2” and add a footnote a reference mark 
to the table title. In footnote  b, change the text “requires you to report N 2O” 
to “requires you to report N 2O or certify to an N 2O standard.”  
• In paragraph 1065.750(a)(2)(i), add the text “ For GC- FIDs that measure 
methane (CH 4) using a FID fuel that is balance N 2, perform the CH 4 
measurement as described in SAE J1151 (incorporated by reference in §1065.1010).”  
• In paragraph 1065.750(a)(2)(iii), change the text “flame- ionization” to “flame 
ionization.”  
• Add a new paragraph 1065.750(a)(3)(xii), with the text “ CH
4, C 2H6, balance 
purified air  and/or N 2 (as applicable).”  
• Add a new paragraph 1065.750(a)(3)(xiii), with the text  “CH 4, CH 2O, CH 2O2, 
C2H2, C 2H4, C 2H4O, C 2H6, C 3H8, C 3H6, CH 4O, and C 4H10. You may omit individual 
gas constituents from this gas mixture. If your gas mixture contains oxygenated 
hydrocarbon, your gas mixture must be in balance purified N 2, otherwise you 
may use balance purified air .”  
374 Harmonization Updates: Subpart I – Testing with Oxygenated Fuels 
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  I: 
• In paragraph 1065.805(d), add the text “as described in §1065.269.”  
• In subsection 1065.845, change the text “alcohol/carbonyl response factor 
(such as RF MeOH)” to “alcohol/carbonyl response factor (RFOHCi[THC -FID]).” Change 
the text  “You are not required to determine the response factor for a 
compound unless you will subtract its response to compensate for a response. 
Formaldehyde response is assumed to be zero and does not need to be determined. Use the most recent alcohol/carbonyl response factors to compensate for alcohol/carbonyl response.” to  “Use the most recently 
determined alcohol/carbonyl response factors to compensate for alcohol/carbonyl response. You are not required to determine the response factor for a compound unless you will subtract its response to compensate for a response.”  
• Change the lettering of subsections 1065.845(a) and 1065.845(b) to  
1065.8 45(b) and 1065.845(c), respectively. Add a new paragraph 1065.845(a) 
with the text, “(a) You may generate response factors  as described in paragraph 
(b) of this section, or you may use the following default response factors, 
consistent with good engineering judgment:,” and a  corresponding table,  
Table 1 of 1065.845 “Default Values for THC FID Response Factor Relative to 
Propane on a C1- Equivalent Basis.”  
• In paragraph 1065.845(a)(10) [re- lettered to 1065.845(b)(10) in the Proposed 
Amendments] , change  the text “calibration gas” to  “calibration gas on a 
C1-equivalent basis ” and change the text “RF MeOH“ to “RF MeOH on a C1-equivale nt 
basis.”  
Harmonization Updates: Subpart J – Field Testing and Portable Emission 
Measurement Systems  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  J: 
• In Table  1 of §  1065.905 following §  1065.905(e), add the text “of this part” 
after the text “ Use § 1065.101 and § 1065.140 through the end of subpart B ” in 
the “Applicability for field testing” column for the “B. Equipment for testing” row. 
• In paragraph 1065.910(a)(2), change the text “Use rigid 300 series stainless 
steel tubing” to  “We recommend using rigid 300 series stainless steel tubing.”  
• In paragraph 1065.920(a), add the text “or if it measures PM using any method 
other than that described in §1065.170(c)(1) .”  
• Delete the current text of paragraph 1065.920( b), and add text for amended 
instructions for recordkeeping for PEMS verification.   
375 • In paragraph 1065.920(b)(7), change the text as indicated by underline and 
strikeout text: “ (7) The PEMS passes this verification  the verification of this 
paragraph (b)  if any one of the following are true for each constituent: .” 
• In paragraph 1065.925(h)(3), delete the text “When spanning the FIDs, use the FIDs' burner air that would be used in- use (for example, use ambient air or a  
portable source of burner air).”  
Harmoniza tion Updates: Subpart K – Definitions and Other Reference 
Information  
The Proposed  Amendments include the following  recent  federal  Part 1065  
amendments  to Subpart  K: 
• In the definition for “C
1 equivalent (or basis)” in § 1065.1001, add the text 
“Molar mass may also be expressed on a C1 basis. Note that calculating HC 
masses from molar concentrations and molar masses is only valid where they 
are each exp ressed on the same carbon basis.”  
• In § 1065.1001, add the following new definition entries:  
o “Enhanced -idle means a mode of engine idle operation where idle speed 
is elevated above warm idle speed as determined by the electronic control module, for example during engine warm -up or to increase 
exhaust temperature.”  
o “High -idle speed means the engine speed at which an engine governor 
function controls engine speed with operator demand at maximum and 
with zero load applied. “Warm high -idle speed” is the high- idle speed of 
a warmed -up engine.”  
o “High -speed governor means any device, system, or element of design 
that modulates the engine output torque for the purpose of limiting the 
maximum engine speed.”  
o “Purified air means air meeting the specifications for purified air in §1065.750. Purified air may be produced by purifying ambient air. The purification may occur at the test site or at another location (such as at a gas supplier's facility). Alternatively, purified air may be synthetically generated from purified oxygen and nitrogen. The addition of other 
elements normally present in purified ambient air (such as Ar) is not 
required. ” 
• In the definition for “Idle speed” in § 1065.1001, change the text “ Idle speed 
means the lowest engine speed with minimum load (greater than or equal to 
zero load), where an engine governor function controls engine speed. For 
engines without a governor function that controls idle speed, idle speed means 
the manufacturer- declared value for lowest engine speed possible with 
minimum load. Note that warm idle speed is the idle speed of a warmed -up 
engine.” to “Idle speed means the engine speed at which an engine governor  
376 function controls engine speed with operator demand at minimum and with 
minimum load applied (greater than or equal to zero).  For engines without a 
governor function that controls idle speed, idle speed means the manufacturer -declared value for lowest engine speed possible with minimum 
load. This definition does not apply for operation designated as “high-idle speed.” “Warm idle speed” is the idle speed of a warmed -up engine.”  
• In § 1065.1001, delete the text of the definitio n for “Nonmethane hydrocarbon 
equivalent (NMHCE).” Add a new definition as follows: “ Nonmethane 
nonethane hydrocarbon (NMNEHC) means the sum of all hydrocarbon species except methane and ethane. Refer to §1065.660 for NMNEHC determination.”  
• In the definition for “Oxygenated fuels” in § 1065.1001, change the text “fuels 
composed of oxygen -containing compounds” to  “fuels composed of at least 
25% oxygen- containing compounds.”  
• In § 1065.1001, delete the definition for “Percent (%)” and add a new definition 
with the following text: “ Percent (%) means a representation of exactly 0.01. 
Numbers expressed as percentages in this part (such as a tolerance of ±2%) have infinite precision, so 2% and 2.000000000% have the same meaning. This 
means that where we specify som e percentage of a total value, the calculated 
value has the same number of significant digits as the total value. For example, 
2% of a span value where the span value is 101.3302 is 2.026604.”  
• In the definition for “Precision” in § 1065.1001, add the text  “See also the 
related definitions of noise and repeatability in this section.”  
• In the definition for “Round” in § 1065.1001, change the text “ to round 
numbers according to NIST SP 811 (incorporated by reference in § 1065.1010) ” 
to “to apply the rounding convention specified in §1065.20(e) .” 
• In the definition for “Test interval,” add “in this chapter” to the end of the last sentence.  
• In the initial unnumbered paragraph in § 1065.1005, delete the text “ 1995 
Edition, “Guide for the Use of the International System, of Units (SI),” .”  
• Include the following recent federal Part 1065 amendments to the table in 
§ 1065.1005(a):  
o Change the column heading “Base SI Units” to “Units in terms of SI base 
units.”  
o Delete the entry for “%.”  
o Change the text “atomic hydrogen -carbon ratio” to “atomic 
hydrogen -to-carbon ratio.”  
o Add an entry for a
g. 
o Add entries for “C d,” “C f,” and “δ .” 
o In the entry for “e,” change the text “3.6-1” to “3.6.”   
377 o In the entry for “f n,” change the text “rotational frequency” to  “angular 
speed” and change the text “ 2.pi.60−1” to “π·30−1.” 
o Add an entry for K v. 
o Change the symbol for “RH%” to  “RH.”  
o Add an entry for “ θ.”  
o Add the unit of seconds (s) to the “Base SI Units” column [“Units in terms 
of SI base units” in the Proposed Amendments] for the t and Δ t variables.  
o Add the unit of “m3” to the “Base SI Units” column [“Units in terms of SI 
base units”  in the Proposed Amendments] for the “V” ( volume cubic 
meter) variable.  
o In the entry for “W,” change the text “3.6” to  “3.6-1.” 
o Add an entry for compressibility factor (Z).  
• Include the following recent federal Part 1065 amendments to the table in 
1065.1005 (b): 
o Add entries for formaldehyde, formic acid, methanol, acetaldehyde , 
ethanol, propanol, sulfuric acid , hydrocarbon, nonmethane -nonethane 
hydrocarbon, nonmethane organic gases , non-oxygenated nonmethane 
hydrocarbon, semi -volatile organic compound, and total hydrocarbon 
equivalent.  
o Delete the entry for sulfur dioxide.  
o In § 1065.1005(c), change the text “to define a quantity ” to “for unit s 
and unit symbols.”  
• In §§  1065.1005(d) and 1065.1005(e), change the text “to define a quantity” to  
“for modifying unit symbols.”  
• Include the following recent federal Part 1065 amendments to the table in 
§ 1065.1005(e):  
o Add the following  subscripts: background (bkgnd), combined (comb), 
composite value (composite), dewpoint (dew), dry condition (dry), duty 
cycle (dutycycle), feedback speed (fn), friction (frict), fuel consumption (fuel) , condition at high- idle (hi,idle), intake air (int), conditions over whi ch 
an engine can operate  (mapped), PM sample media (media), mixture of 
diluted exhaust and air  (mix), normalized (norm), power (P), after the test 
interval  (post), before  the test interval  (pre), stoichiometric product 
(prod) , record rate (record), engine strokes per power stroke (stroke), 
torque (T), alternate test quantity (test,alt), vacuum side of the sampling 
system (vac), and calibration weight  (weight).  
o Delete the entry for “slip.”   
378 • Include the following recent federal Part 1065 amendments to the tab le in 
1065.1005 (f)(2):  
o Add entries for the molar mass of the following quantities: methanol, 
ethanol, acetaldehyde, urea, propanol, methane, formaldehyde, ammonia, and effective molar mass of nonmethane- nonethane 
hydrocarbon.  
o Move the entry for the molar mass of propane to be adjacent to the entry for molar mass of propanol.  
o In footnote (b), change the text “ THC, THC E, NMHC, and NMHCE are 
defined by an atomic hydrogen -to-carbon ratio” to  “THC, THCE, NMHC, 
NMHCE, and NMNEHC are defined on a C1  basis and are based on an 
atomic hydrogen -to-carbon ratio”  and add the text “ (with β, γ, and δ  
equal to zero). ”  
o Add a Footnote (b) reference mark to the new entry for nonmethane- nonethane hydrocarbo n. 
• Add the following acronyms and abbreviations to the table in 1065.1005(g): acrylonitrile butadiene styrene  (ABS), for example (e.g.), Fourier transform 
infrared  (FTIR), g as chromatograph with a flame ionization detector (GC -FID), 
high efficiency particu late air  (HEPA), incorporated by reference ( IBR), in other 
words (i.e.), magnetopneumatic detection  (MPD), porous layer open tubular  
(PLOT), paramagnetic detection  (PMD), rechargeable energy storage system  
(RESS ), response factor penetration fraction  (RFPF ), surface acoustic wave  
(SAW ), standard estimate of error (SEE), total hydrocarbon flame ionization 
detector ( THC FID ), and inverse student t test function in Microsoft Excel  
(TINV) .  In the entry for “FID,” change the text “flame -ionization” to “flame 
ionization.”  
• In § 1065.1010, change the ASTM D2986 reference description from 
“ASTM  D2986- 95a (Reapproved 1999), Standard Practice for Evaluation of Air 
Assay Media by the Monodisperse DOP (Dioctyl Phthalate) Smoke Test ” to 
“ASTM  D2986 – 95a, Standard Practi ce for Evaluation of Air Assay Media by the 
Monodisperse DOP (Dioctyl Phthalate) Smoke Test, approved September  10, 1995.”  
• In § 1065.1010, change the reference edition for NIST Special Publication 811 
from “1995 Edition” to “2008 Edition.”  
The Proposed Amendments above reflect changes made to the corresponding 
provisions in the federal Part 1065, up to and including U.S.  EPA’s final regulatory 
amendments, “Improvements for Heavy- Duty Engine and Vehicle Test Procedures, 
and Other Technical Amendments,” published in the Federal Register on June 29, 2021.  The purpose of these changes is to harmonize California’s Part 1065 
with subsequent amendments to the f ederal Part 1065, except as necessary to uphold  
379 the stringency of California emission standards, maintain consistency with existing 
California SORE regulation, or prevent confusion.  
Rationale . These changes, additions,  and deletions are identical to the changes, 
additions,  and deletions in the equivalent sections, subsections, and paragraphs of  the 
federal Part 1065 due to amendments adopted at the federal level subsequent to 
June 2011. The Proposed Amendments to this section are necessary to establish 
consistency  with similar provisions in the federal regulations for small nonroad engines. 
Chan ges to References of Equipment Types, Engine Types, and Fuel  
Purpose. The Proposed  Amendments include the following changes to clarify that 
California’s Part 1065 does  not apply  to locomotives,  licensed  on-road light- duty 
motor  vehicles,  or marine  vessels that are not SORE  equipment:  
• Change “vehicles, equipment, and vessels” to “engines and equipment,” “ an 
engine assembly or piece of equipment,” “piece of equipment,” or 
“equipment,” depending on the context of the sentence, in the following  
sections: 1065.1 (c)(1), 1065.10(c)(1), 1065.15(f)(1)(ii), 1065.110(a)(1)(iv), 
1065.9 10(d)(1), and 1065.910(d)(2).   
• Delete “vehicles” from the following sections: 1065.101(e), 1065.110(f), 
1065.1 30(b)(1), 1065.145(b),  and 1065.695(c)(7)(x).  
• Change “vehicles” to “equipment” or “piece of equipment,” depending on the context of the sentence, in the following sections: Table 1 of 1065.303, 
1065.3 45(a), 1065.405(f), 1065.695(c)(12)(xiv), 1065.905(c)(3), 1065.910, and 
1065.9 10(a)(2).  
• Add “or equipment” to “vehicle,” in the context of PEMs testing, in § 1065.910(c).  
• Delete examples involving motor vehicles and/or special provisions relating to light duty motor vehicles or vehicles equipped with automatic transmissions from the following section: 1065.510(f)(4)(i), 1065.512(b)(2), and 1065.595(e).  
• Delete §  1065.610(d)(3), which describes special provisions for engines 
intended for propulsion of vehicles with automatic transmissions.  
• Omit a reference to 40 CFR 1066.635 from § 1065.260(e), which descri bes 
methods specific to light -duty vehicle engine testing.  
• Change the example “locomotive notch setting” to “throttle setting” in 1065.140 (d)(2)(iv).  
• Delete other examples relating to vessels or locomotives from the following sections: 1065.110(a)(1)(iv), 1065.145(b), 1065.210(a), and the definition for “mode” in 1065.1001.  
• Omit other examples relating to vessels or locomotives in the corresponding amended federal text in § 1065.530.   
380 The Proposed Amendments include the following changes to clarify that Cali fornia’s 
Part 1065 applies to spark -ignition engines and to prevent confusion resulting from 
including text in the SORE regulations about compression- ignition engines produced 
during the 2000 and later model years, which are not SORE.  
• Delete text for speci al provisions or requirements for testing for 
“compression -ignition engines” from the following sections: 1065.145(c)(2)(ii), 
1065.145 (d)(1)(ii), 1065.145(e)(2)(ii), 1065.145(e)(3)(ii), 1065.230(d)(2), 
1065. 240(d)(2), and 1065. 260(c).  
• Delete text related  to “compression -ignition engines” from the following 
sections: 1065.362, 1065.595(e), 1065.655(c)(1), 1065.667(d) [re- lettered], 
1065. 670(a), and 1065. 920(b)(2)(iii ). Delete subsection 1065.602(l)(1), relating to 
NO x flow estimates for compression -ignition engines, and 
subsection 1065.670(a), relating to intake air humidity correction for 
compression -ignition engines, and add “[Reserved]” placeholder text.  
• Delete the definition for “compression- ignition engine” in §  1065.1001 and 
delete the abbreviation fo r compression -ignition from §  1065.1005(g).  
• Delete the entries for “diesel fuel” and “residual fuel blends” from Table 1 of 
§ 1065.655.  
• Omit other examples relating to compression -ignition engines in the amended 
federal text from §  1065.518.  
The Proposed Amendments include the following changes to clarify that California’s 
Part 1065 applies to spark -ignition engines and to prevent confusion resulting from 
the inclusion of text about diesel engines and control of diesel -engine emissions, given 
SORE regulati ons do not apply to compression -ignition engines produced during the 
2000 and later model years. 
• Omit provisions relating to “diesel exhaust fluid” or “DEF” without 
replacement, except with “[Reserved],” in the following sections of  amended 
federal text that is being included in Proposed Amendments to harmonize the 
California Part 1065 with the federal Part 1065 : Table 1 of 1065.205, Table  1 of 
1065.3 03, 1065.307(d)(4), 1065.307(e)(iv), 1065. 307(e)(vi), Table  1 of 1065.307, 
1065.6 55(a). 1065.6 55(d), and 1065.667. 
• Provisions in the amended federal text relating to “diesel exhaust fluid” or “DEF” in certain calculations are replaced with “any other fluids injected into 
the exhaust,” “any other injected fluids,” “any injected fluids,” or “any flui d 
injected” in the following sections, subsections, or paragraphs: 1065.307(d)(9), 
1065.5 43, 1065.643, 1065.655(c), 1065.655(d), 1065.655(e), Table 1 of 
1065.6 55, and 1065.667(d).  
Rationale . The federal Part 1065 describes general engine testing procedures and 
requirements as established by U.S. EPA. It includes text representative of the range  
381 of engines it covers. The Part 1065 adopted into the California Code of Regulations in 
2012, with California -specific changes, applies to SORE. While some types of SORE 
equipment, such as go -karts and utility carts, could reasonably be described as 
vehicles, they are regulated in California using equipment -based and engine -based 
standards. In the context of PEMS testing, the word “vehicle” may refer to either a piece of equipment or to a vehicle used to transport or follow the equipment. 
Otherwise, it is necessary to delete or modify text with the word “vehicle” to prevent confusion.  Similarly, it is necessary to delete text related to “Diesel Exhaust Fluid” to 
prevent  confusion.  Diesel Exhaust Fluid, or DEF, refers to a fluid injected into the 
exhaust from diesel engines to help reduce NO
x emissions. The use of the diesel 
exhaust fluid or DEF, and the inclusion of special provisions related to DEF, in text adopted to o therwise harmonize with federal amendments could be confusing 
because SORE regulations do not apply to diesel engines produced during the 2000 
and later model years . 
Amending or Removing the Phrase “Selective Enforcement Audit”  
Purpose. The federal  regulatory term,  “selective enforcement  audit,”  is incorporated  
in three  sections  in the Part 1065  regulations  that CARB  adopted into the California 
Code  of Regulations.  However,  this term is not used  in other  California SORE  
regulations.  To prevent confusion  for manufacturers  and improve  regulatory certainty,  
the Proposed  Amendments delete the federal  regulatory term,  “selective  enforcement  
audit,”  throughout  the current regulations.  The Proposed  Amendments also include 
replacement  text, “compliance  testin g,” if needed  to preserve  the meaning  or 
requirements  of the affected  provisions.  The Proposed  Amendments include the 
following changes,  as indicated  by underline and strikeout:  
• In § 1065.2 (a), regarding manufacturer responsibilities for submitting 
informa tion under Part 1065: “You are responsible for statements and 
information in your applications for certification, requests for approved 
procedures,  selective enforcement audits c ompliance tes ting, laboratory audits, 
production -line test reports, field test  reports, or any other statements you 
make to us related to this part 1065. ”  
• In § 1065.170(c)(1)(iii), regarding b atch sampling for gaseous and PM 
constituents and PM sample media: “Note that we will use pure PTFE filter 
material for compliance testing, a nd we may require you to use pure PTFE filter 
material for any compliance testing we require , such as for selective 
enforcement audits.” 
• In § 1065.695(a), regarding data requirements: “We may require different information for different purposes, such as fo r certification applications, 
approval requests for alternate procedures,  selective enforcement audits 
compliance testing , laboratory audits, production line test reports, and field test 
reports.   
382 Rationale . These changes are necessary to improve consistency and prevent confusion 
for the reader by correcting an oversight that occurred at the time the federal 
regulations were incorporated into the California Code of Regulations in 2012.  Federal 
regulations use the term “selective enforcement audit” to refer t o provisions 
substantially similar to the provisions that California SORE regulations describe as 
“compliance testing ” for in-use testing and validation of engines in § 2407, “ New 
Engine Compliance and Production Line Testing – New Small Off -Road Engine 
Selection, Evaluation, and Enforcement Action.” The term “ selective enforcement 
audit”  is not used in other California SORE regulations.  The proposed changes would 
not result in cost impacts to manufacturers because manufacturers already must follow applic able CCR  § 2407 requirements.  
Preface  
Purpose. The current regulations include the following preface  text before  and after  
the table  of contents:  
Befo re the table  of contents : 
“Note:  This appendix  shows the entirety of regulatory amendments to the test 
procedures  titled  below,  which  were  approved  by the Air Resources 
Board  on December  16, 2011,  and refined  via subsequent  conforming  
modifications  authorized  under  Resolution 11-41. Incorporated  by 
reference  into these  test procedures  are portions  of Title 40 of the Code  
of Federal  Regulations  (CFR)  Part 1065 – Engine- Testing  Procedures,  
Subparts  A through  K inclusive,  as amended  June 28, 2011;  and, the 
internally referenced  section s of Title 40 CFR,  Parts  60, 80, 86, 90, 1054,  
and 1068.  Sections  that have  been  included  in their entirety are set forth  
with the section  number  and title. California  provisions  that replace  
specific federal  language  provisions  are denoted  by the words  “DELETE”  
for the federal  language  and “REPLACE  WITH”  or “ADD”  for the 
California language.  The notation  [ * * * * * ] or [ ... ] means that the 
remainder  of the CFR text for a specific  section  is not shown  in these  
procedures  but has been  incorporated  by reference,  with only the 
printed  text changed.  CFR sections that are not listed are not part of 
California’s test procedures.  If there  is any conflict between  the 
provisions  of this document and the California  Health  and Safety  Code,  
Division 26, or Title 13 of the California Code  of Regulations  (CCR),  the 
Health  and Safety  Code  and Title 13 apply.  
 This document  is all newly  adopted text.”  
After  the table  of contents : 
“The  following provisions  of Part 1065,  Title 40, Code  of Federal  Regulations,  
as promulgate d by the United  States  Environmental  Protection  Agency  on the 
date listed, are adopted and incorporated  herein by this reference  for 2013 
model  year and later small  off-road engines as the California  Exhaust  Emission  
383 Standards  and Test Procedures  for New 2013 and Later Small  Off-Road  
Engines,  except  as altered  or replaced  by the provisions  set forth  below.”  
“SOURCE: 76 FR 37977, June 28, 2011, unless otherwise noted.”  
The Proposed  Amendments delete this preface  text and add the following updated 
text before  the table  of contents:  
“Note:  This document provides the entirety of the California Exhaust Emission 
Standards and Test Procedures for New 2013 and Later Small Off -Road 
Engines; Engine- Testing Procedures (Part  1065), as adopted by the 
California Air Resources Board  (CARB)  on December  16, 2011, with 
additional  conforming modifications authorized under Resolution 11-41 
on October  25, 2012, and amended on [insert amendment date] . These 
standards and test procedures are incorporated  by reference in Title 13, 
California Code of Regulations, § 2403. The Part 1065 section numbers, 
titles, and text correspond to same -numbered sections in Title 40 of the 
Code of Federal Regulations (CFR) Part  1065 – Engine- Testing 
Procedures, with Califor nia-specific modifications as necessary to 
maintain the stringency of California emission standards and provide 
consistency with other California regulations. CFR sections that are not 
listed herein are not a part of this Part 1065. The 2011/2012 CARB 
rulemaking incorporated  by reference portions of Title 40 CFR Part  1065, 
including Subparts A through K, as amended June 28, 2011; for clarity, 
the 2021 CARB rulemaking included the entirety of the language from 
those portions of Title 40 CFR Part 1065, including Subparts A through K, 
incorporated by reference in Part 1065 from the 2011/2012 rulemaking into Part 1065. The 2011/2012 CARB rulemaking also incorporated by 
reference the internally referenced sections in Part  1065 to Title 40 CFR 
Parts  2, 51, 80,  86, 1054, and 1068 , as amended May 26, 2011, 
March  30, 2011,  December 21, 2010, April 8, 2011, November 8, 2010, 
and April 30, 2010, respectively. The 2021 CARB rulemaking included 
those portions of Title 40 CFR Part  1065 Subparts A through  K, as 
amended between June 28, 2011, and June 29, 2021, in Part 1065. The 
2021 CARB rulemaking incorporated by reference the internally 
referenced sections in Part 1065 to Title  40 CFR Part 86 as amended 
June 29, 2021, and Title 40 CFR Part 1090 as adopted 
December  4, 2020. The 2021 CARB rulemaking removed the references 
to 40 CFR Parts 2, 51, 80, 1054, 1065,  and 1068, and those CFR Parts are 
no longer incorporated by reference in this Part 1065. If there is any 
conflict between the provisions of this document and the C alifornia 
Health and Safety Code, Division 26, or Title 13 of the California Code of 
Regulations, the Health and Safety Code and Title 13 apply. ”  
384 The Proposed Amendments include a placeholder for the amended date, “[insert 
amended date],” that will be upda ted to reflect the CARB adoption date of the 
Proposed Amendments to Part 1065 . 
Rationale . An updated preface is necessary for accuracy and clarity because, once the 
Proposed Amendments are approved, California Part  1065 will no longer be 
comprised of “all newly adopted text.” Instead, California Part 1065 will include text 
adopted by the 2011/2012 rulemaking as amended by the current rulemaking. The 
Proposed Amendments also provide an updated date of publication for the federal Part 1065 that is the source material for the Proposed Amendments, and updates the list of other 40 CFR parts internally referenced by the amendments and their 
associated publication dates. Two CFR parts, CFR Parts 60 and 90, were listed in the 
2011/2012 preface but were not cited later in California Part 1065, and therefore need not be incorporated by reference. The updated publication dates are necessary to maintain CARB’s ability to independently implement or enforce its regulations should 
U.S. EPA make a change that does not suppor t the stringency of California emission 
standards or is otherwise not consistent with other California SORE regulations. Also, 
Title 1, California Code of Regulations, § 20(c)(3), generally prohibits the incorporation 
by reference of material into Californ ia regulations without a date of publication or 
issuance. The 2011/2012 preface text that explains why some federal Part 1065 text is 
not shown is now not necessary because, for clarity, the document  now includes the 
entirety of the language from those portions of Title 40 CFR Part  1065 incorporated 
by reference in Part 1065 by the 2011/2012 rulemaking into Part 1065. 
Subpart A – Applicability and General Provisions  
§ 1065.1(d)  
Purpose. The current regulations in § 1065.1 specify  the applicability and provi sions of 
Part 1065.  The current  regulations in § 1065.1(a)  specifies the following: 
“This  part applies  to 2013 and later model  year small  off road engines 
regulated  under  Title 13, California Code  of Regulations,  Chapter  9, Article  1, 
and subject  to the emission standards  in § 2403(b)(1)  of that Article.  These  
provisions  do not apply  to engines  and equipment  that fall within the scope  of 
the preemption  of Section 209(e)(1)(A)  of the federal  Clean  Air Act, as 
amended,  and as defined  by regulation  of the Environmental  Protection  
Agency.  
Section  1065.1(d) specifies: “ Paragraph (a) of this section identifies the parts of the 
CFR that define emission standards and other requirements for particular types of 
engines. ” The Proposed Amendments change the text “CFR” to “California Code of 
Regulations”  
 
Rationale . This change is necessary to provide clarity and improve consistency by 
correcting an oversight that occurred at the time the federal Part 1065 regulations  
385 were incorporated into the California Code of Regulations. In 2012, CARB modified 
the SORE regulations to adopt portions of the federal Part 1054 and Part 1065, to 
improve alignment of the certification and testing requirements without any changes 
in the stringency of the emission standards and associated test procedures, and without any cost impacts. Changing “CFR” to “California Code of Regulations” in § 1065(d) is necessary to provide consistency with the incorporation of federal 
regulations into California’s SORE regulations and does not change any of  the 
standards and test procedures. Section 1065.1(a) currently specifies that this part 
exists and applies under CARB regulations rather than federal regulations.  
§ 1065.1(g)  
Purpose. The Proposed Amendments change the address for the CARB website that 
provides additional information regarding the test procedures from 
“http://www.arb.ca.gov/msprog/offroad/sore/sore.htm” to 
“https://ww2.arb.ca.gov/our- work/programs/small -off-road-engines- sore.” 
Rationale . This change is necessary because CARB recently implemented a redesigned 
web platform that changed webpage addresses for the SORE Program and other CARB programs.  
§ 1065.2  
Purpose. The current regulations in § 1065.2 specify  manufacturer responsibilities for 
submitting  information  to CARB.  The Proposed  Amendments  make  corrections  in 
three  subsections:  
• In § 1065.2(b), delete unnecessary references to federal regulations, as 
indicated by strikeout in the following: “In the standard -setting part and in 
40 CFR 1068.101,  we describe your obligation to report truthful and complete 
information and the consequences of failing to meet this obligation. See  also 18 
U.S.C. 1001 and 42 U.S.C. 7413(c)(2). ”  
• In § 1065.2(e), replace references to federal regulations with references to 
applicable California SORE regulatio ns, as indicated by strikeout in the 
following: “ See 40 CFR 1068.10  Title 17, California Code of Regulations, 
Section  91000 -91022 for provisions related to confidential information. Note 
however that under  40 CFR 2.301  California Government Code 6254.7 , 
emission data is generally not eligible for confidential treatment. ” 
• In § 1065.2(f), replace the reference to federal regulations with a reference to 
applicable California SORE regulations, as indicated by strikeout in the 
following: “ Nothing in this part should be interpreted to limit our ability under  
Clean Air Act section 208 (42 U.S.C. 7542)  Title 13, California Code of 
Regulations, Section 2400, and the California Health and Safety Code to verify 
that engines conform to the regulations. ”  
386 Rationale . The se changes are necessary to prevent confusion for the reader by 
correcting an oversight that occurred at the time the federal regulations were 
incorporated into the California Code of Regulations in 2012, with changes to address 
other California -specific regulations.  The federal Part  1065 regulations previously 
adopted into the California Code of Regulations referred to the relevant portions of the Code of Federal Regulations. For SORE in California, for which California’s Part 
1065 was adopted, the relevant standards and other requirements are those in Title 
13, California Code of Regulations, Chapter 9, Article 1, and California’s Part 1054. Referencing the f ederal  regulations here, rather than the applicable California 
regulations,  could create  confusion.  The proposed changes would not result in cost 
impacts to manufacturers because manufacturers already must follow the cited California and federal regulations, as applicable.  
§ 1065.10(c)(5)  
Purpose. The Proposed Amendments change the text, “ You may ask to  use emission 
data collected using other procedures, such as those of the California Air Resources 
Board or the International Organization for Standardization ,” to “ You may ask to use 
emission data collected using other procedures, such as those of the Uni ted States 
Environmental Protection Agency or the International Organization for 
Standardization .” This change establishes that manufacturers may request permission 
to follow U.S. EPA procedures for SORE testing.  
 Rationale . This change is necessary to pro vide the flexibility for manufacturers 
intended under federal Part  1065 by correcting an oversight that occurred at the time 
the federal Part 1065 regulations were incorporated into the California Code of Regulations. The federal regulations contained a provision allowing those conducting testing under federal Part 1065 to request to use emission data collected using procedures specified by others than U.S. EPA, including CARB. This text was 
inadvertently incorporated into California’s Part 1065 in the 2012 adoption.  
Subpart B – Equipment Specifications  
§ 1065.170   
Purpose. The current regulations in § 1065.170 specify  requirements for batch  
sampling for gaseous and PM constituents.  Batch  sampling involves collecting  and 
storing  emissions  for later analysis. U.S. EPA’ s final regulatory amendments published  
in June  2021  include the following new text for 40 CFR Part 1065.170  in the initial 
unnumbered  paragraph:  
“You  may stop emission sampling anytime  the engine  is turned  off, consistent  
with good  engineering  judgment.  This is intended  to allow for higher  
concentrations  of dilute exhaust  gases  and more  accurate  measurements.  
Account  for exhaust  transport delay  in the sampling system  and integrate  over 
the actual  sampling duration  when determining  ndexh. Use good engineering   
387 judgment  to add dilution air to fill bags  up to minimum read volumes,  as 
needed.”  
The Proposed Amendments would incorporate the above U.S. EPA amendment into 
California Part  1065.170 to harmonize the California Code of Regulations with the 
recent federal regulation changes, with one modification. The Proposed Amendments would change the text “anytime” in the first sentence to “ during any time .”  
Rationale . The addition of these sentences is necessary to provide consistency with 
(i.e., “harmonize”) recent changes made to the corresponding provisions in the federal 
Part 1065. The proposed modifications to the federal text are necessary to improve 
clarity and grammar.  
§ 1065.170(b)(2)  
Purpose. T he current federal  regulations  include the following new text for 40 CFR 
Part 1065.170(b):  
“(2) (191 ±11) °C for TeflonTM and 300 series stainless steel  used  with measuring  
THC or NMHC  from  compression-ignition engines,  two-stroke  spark -ignition 
engines,  and four-stroke  spark -ignition engines at or below  19 kW. For all other  
engines and pollutants,  these materials  may be used  for sample  temperatures  
up to 202 °C.” 
The Proposed  Amendments would  incorporate  the above  text into California 
Part 1065.170 (b) to harmonize  the California Code  of Regulations with the recent  
federal  regulation  changes,  with modifications  to make  the changes specific  to 
California, as noted  in underline and strikeout in the following: 
“(2) (191 ±11) °C for TeflonTM and 300 series  stainless steel  used  with measuring  
THC or NMHC  from  compression-ignition engines,  two-stroke  spark -ignition 
engines,  and four-stroke  spark -ignition engines at or below  19 kW. For all other  
engines and pollutants,  these materials  may be used  for sampl e temperatures  
up to 202 °C.” 
Rationale . The addition of these sentences is necessary to provide consistency with 
recent changes made to the corresponding provisions in the federal Part 1065. The 
rationale for not including the “ compression -ignition engines ” text is the same as that 
provided in the Global Amendments subsection in this section G, “Changes to 
References of Equipment Types, Engine Types, and Fuel .” The proposed text is 
otherwise identical to the text in the  same -numbered paragraph  of the federal  
Part 1065. 
§ 1065.170(b)(2) Table 1  
Purpose. The current federal and California regulations include Table 1, which 
specifies container m aterials for gaseous batch sampling . Recent U.S. EPA 
amendments to the federal regulations change the title of the table from “Gaseous  
388 Batch Sampling Container Materials” to “Container Materials for Gaseous Batch 
Sampling,” change the heading for the second and third columns from “Engines” to 
“Engine Type, ” add the text “N 2O” to the second row “Emissions” column, and 
delete all table footnotes.  The Proposed Amendments would incorporate these 
changes into Table 1 of California Part  1065.170(b) to harmonize the California Code 
of Regulations with the recent federal regulation changes, with one modification to 
make the changes specific to California.  The Proposed Amendments change the 
column  heading “Compression- ignition, two -stroke spark ignition, 4 - stroke spark -
ignition <19 kW” to “Two- stroke spark -ignition” and “Four -stroke spark -ignition at or 
below 19 kW” with a li ne break between them.  
Rationale . These proposed changes are necessary to provide consistency with recent 
changes made to the corresponding provisions in the f ederal Part 1065. Deleting the 
Table  1 footnotes aligns the California SORE regulations with the federal regulations 
and removes redundant information. The recent federal amendments and corresponding Proposed Amendments described earlier in this section add the 
information currently presented in California Table 1 footnotes (1) through (4) to the paragraph text of §§  1065.170( b)(1) and (2). The rationale for not including the 
“compression -ignition” engine type is the same as that provided in the Global 
Amendments subsection in this section G, “Changes to References of Equipment 
Types, Engine Types, and  Fuel.” The proposed text is otherwise identical to the text in 
the corresponding table in the federal Part 1065. 
Subpart C – Measurement Instruments  
§ 1065.205 Table 1  
Purpose. The current regulations in this section specify required and recommended 
perfo rmance criteria for measurement instruments, with recommended performance 
specifications listed in Table  1 of §  1065.205. Recent federal amendments included 
two new rows in Table  1 for “F uel mass scale ” and “DEF mass scale,” each noted with 
a new footnote d, “Base performance specifications for mass scales on differential 
mass over the test interval as described in §1065.307(e)(9).” The federal amendments also added a new footnote  c, “The procedure for accuracy, repeatability and noise 
measurement described  in §1065.305 may be modified for flow meters to allow noise 
to be measured at the lowest calibrated value instead of zero flow rate. ” The federal 
amendments noted the already adopted “ Fuel mass flow rate meter,” “Total diluted 
exhaust meter (CVS) ,” and “D ilution air, inlet air, exhaust, and sample flow meters” 
table entries with the new footnote c. The Proposed Amendments would incorporate 
the table row “fuel mass scale” and footnotes c and d into California Part  1065. 202 to 
harmonize the California Code of Regulations with the recent federal regulation 
changes, but would not incorporate the table row for “DEF mass scale.”  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal P art 1065. The omission of the 
federal regulation text for the table row for “DEF mass scale” is necessary to prevent   
389 confusion. DEF refers to Diesel Exhaust Fluid, which is used to reduce NO x emissions 
from diesel engines. The use of diesel exhaust fluid or DEF, and the inclusion of 
special provisions related to DEF, in text adopted to otherwise harmonize with federal 
amendments could be confusing because SORE regulations do not apply to diesel engines produced during the 2000 and later model years. The rationale for not 
including the table row for “DEF mass scale” is the same as that provided in the 
Global Amendments subsection in this section G, “Changes to References of 
Equipment Types, Engine Types, and Fuel .” The proposed text is otherwise identical 
to the text in the  same -numbered paragraph  of Title 40, Code of Federal Regulations, 
Part 1065. 
Subpart D – Calibrations and Verifications  
§ 1065.303 Table 1  
Purpose. Subpart  D of Part 1065  specifies  required  and recommended  calibrations  
and verifications  of measurement  systems, and Table  1 of § 1065.303  provides  a 
summary that indicates  the minimum frequency  for their performance.  The Proposed  
Amendments would  incorporate  recent  U.S. EPA amendments into California 
§ 1065.303 Table  1 to harmonize  the Califo rnia Code  of Regulations  with the recent  
federal  regulation  changes as follows:   
• Under the “§ 1065.30 3: Linearity verification ” section of the table, make the 
following changes:  
o Change the text “Electrical power:” to “Electrical power, current, and 
voltage :” and add a reference mark for footnote b.  
o Change the entry heading “Fuel flow:” to “Fuel mass flow rate:.”  
o Add a new entry for “Fuel mass scale: Upon initial installation, within 370 days before testing, and after major maintenance.”  
o Change the entry heading “Clean gas and diluted exhaust flows:” to 
“Intake- air, dilution air, diluted exhaust, and batch sampler flow rates:,” 
add a footnote c reference mark, and delete the text “unless flow is verified by propane check or by carbon or oxygen balance.”  
o Chan ge the entry heading “Raw exhaust flow:” to “Raw exhaust flow 
rate:,” and delete the text “unless flow is verified by propane check or by carbon or oxygen balance.”  
o Change the entry heading “Gas analyzers:” to “Gas analyzers (unless otherwise noted):.”  
o Change the text “§ 1065.341: CVS and batch sampler verification”  in the 
“Type of calibration or verification” column to “CVS and PFD flow 
verification (propane check)” and delete the reference mark for footnote 
b. For its corresponding entry in the “Minimum-f requency” column, add 
a new reference mark for footnote e.   
390 • Under the “ § 1065.360: FID calibration THC FID optimization, and THC FID  
verification” section of the table, add a new entry for “Verify C 2H6 response for 
THC FID analyzers if used for NMNEHC determination: upon initial installation, 
within 185 days before testing, and after major maintenance.”  
• Add two new table rows for minimum frequencies for the following types of calibration or verificatio n: 
o § 1065.366: Interference verification for FTIR analyzers—Upon initial installation and after major maintenance.  
o §1065.369: H
2O, CO, and CO 2 interference verification for ethanol 
photoacoustic analyzers —Upon initial installation and after major 
maintenance.  
• Make the following changes to footnote text:  
o Footnote a: Change the text “more frequently” to “more frequently than 
we specify.” Footnote a applies to the “Minimum -frequency” column 
heading.  
o Footnote b: Change the text “The CVS verification described i n 
§ 1065.341 is not required for systems that agree within ± 2% based on a 
chemical balance of carbon or oxygen of the intake air, fuel, and diluted 
exhaust ” to “ Perform linearity verification either for electrical power or 
for current and voltage .”  
o Footn ote c: Add footnote c with the text “[Reserved].”  
o Footnote d: Add footnote d with the text “ Linearity verification is not 
required if the flow signal’s accuracy is verified by carbon balance error verification as described in §1065.307(e)(5) or a propane check as 
described in §1065.341.”  
o Footnote e: Add footnote e with the text “CVS and PFD flow verification (propane check) is not required for measurement systems verified by linearity verification as described in §1065.307 or carbon balance error verification as described in §1065.341(h) .” 
The Proposed Amendments do not include the recent federal amendment that adds a 
new entry for “DEF mass scale” under the “§ 1065.307: Linearity verification” section 
of the table .  
The Proposed Amendments also make a change to make the previously adopted federal Part 1065 text specific to California SORE regulations. Under the entry for 
“§ 1065.345: Vacuum leak,” change the text “vehicle” to “equipment” in the 
corresponding entry in the “Minimum -frequency” column, as i ndicated in underline 
and strikeout text in the following: “For field testing: After each installation of the sampling system on the  vehicle  equipment , prior to the start of the field test, and after 
maintenance such as pre- filter changes. ”  
391 Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. The omission of the 
federal table row for Diesel Exhaust Fluid (DEF)  mass scale is necessary to prevent 
confusion because the California SORE regulations do not apply to diesel engines 
produced during the 2000 and later model years. The rationale for not including the federal table row for “DEF mass scale” is the same as that provided in the Global 
Amendments subsection in this section  G, “Changes to References of Equipment 
Types, Engine Types, and Fuel .” The rationale for the proposed modification to make 
the previously adopted federal text specific to California SORE regulations is the same 
as that described in the Global Amendments subsection, “ Updates to Harmonize with 
Amended Federal Text .” The propos ed changes are otherwise identical to the table 
text in the  same -numbered section of the federal Part 1065.  
§ 1065.307(d)(4)  
Purpose. The current regulations in § 1065.307 specify  provisions  for linearity 
verification,  and paragraph  (d) describes  recommen ded methods  for generating  
reference  values  for the linearity verification  protocol  in paragraph  (c) of this section.  
The current federal  regulations include the following recent  amendments  made  by 
U.S. EPA to paragraph  (d)(4) to correct or account for buoyancy effects  and flow 
disturbances to improve  the flow measurement,  as indicated  by underline  and 
strikeout  text: 
Fuel and DEF mass  flow rate. Operate  the engine at a series of constant  fuel-
flow rates  or recirculate  fuel back  to a tank through the fuel flow meter  at 
different  flow rates.  Use a gravimetric reference measurement  (such  as a scale,  
balance,  or mass  comparator)  at the inlet to the fuel-measurement  system  and a 
container.  Use a stopwatch  or timer to measure the time intervals  over which  
reference  masses  of fuel are introduced  to the fuel measurement  system.  The 
reference  fuel mass  divided by the time interval  is the reference  fuel flow rate. 
fluid pass through  the mass  flow rate meter.  Use good  engineering  judgment  to 
correct the reference  mass  flowing through the mass  flow rate meter  for 
buoyancy effects  from  any tubes,  temperature  probes,  or objects  submerged  in 
the fluid in the container that are not attached  to the container.  If the container  
has any tubes  or wires  connected  to the container,  recalibrate  the gravimetric 
reference  measurement  device  with them  connected  and at normal  operating  
pressure  using  calibration  weights  that meet  the requirements in §1065.790.  
The corrected  reference  mass  that flowed  through  the mass  flow rate meter 
during  a time interval  divided by the duration  of the time interval  is the average  
reference  mass  flow rate. For meters  that report a different  quantity  (such  as 
actual  volume,  standard  volume,  or moles),  convert the reported  quantity to 
mass.  For meters  that report a cumulative  quantity calculate  the average  
measured  mass  flow rate as the difference  in the reported  cumulative  mass  
during  the time interval  divided by the duration  of the time interval.  For 
measuring  flow rate of gaseous  fuel prevent condensation on the fuel container  
and any attached  tubes,  fittings,  or regulators.   
392 The Proposed Amendments would incorporate the above U.S. EPA amendments into 
California § 1065.307(d)(4)  to ha rmonize the California Code of Regulations with the 
recent federal regulation changes, with one modification. In the paragraph title, the 
Proposed Amendments do not include “and  DEF.”  
Rationale . The proposed modification to the federal text, omit the federal regulation 
text “and DEF,” is necessary to prevent confusion. DEF refers to Diesel Exhaust Fluid, 
which is used to reduce NO x emissions from diesel engines. The use of diesel exhaust 
fluid or DEF, and the inclusion of special provisions related to DEF,  in text adopted to 
otherwise harmonize with federal amendments could be confusing because SORE 
regulations do not apply to diesel engines produced during the 2000 and later model 
years . The rationale for not including the text “and DEF” is the same as tha t provided 
in the Global Amendments subsection in this section G, “Changes to References of 
Equipment Types, Engine Types, and Fuel .” 
§ 1065.307(d)(9)  
Purpose. The current text of § 1065.307(d)(9),  and the corresponding  federal  text prior  
to June 2021,  consists of one sentence:  “Mass.  For linearity verification  for gravimetric 
PM balances,  use external  calibration  weights  that meet  the requirements in 
§1065.790. ” The current federal  regulations  include the following recent  amendments  
made  by U.S. EPA to paragraph  (d)(9),  as indicated  by underline and strikeout  text: 
“Mass . For linearity verification  for gravimetric PM balances,  fuel mass  scales,  
and DEF mass  scales,  use external  calibration  weights  that meet  the 
requirements  in §1065.790.  Perform the linearity verification  for fuel mass  scales  
and DEF mass  scales  with the in-use container,  installing all objects  that 
interface  with the container.  For example,  this includes all tubes,  temperature  
probes,  and objects  submerged  in the fluid in the container;  it also includes  
tubes,  fittings,  regulators,  and wires,  and any other  objects  attached  to the 
container.  We recommend  that you develop  and apply  appropriate  buoyancy 
corrections  for the configuration  of your mass  scale  during  normal  testing,  
consistent  with good  engineering  judgment.  Account  for the scale  weighing  a 
calibration  weight  instead  of fluid if you calculate  buoyancy corrections.  You 
may also correct for the effect  of natural  convection  currents  from  temperature  
differences  between  the container  and ambient  air. Prepare  for linearity 
verification  by taking the following steps for vented  and unvented  containers:   
(i) If the container is vented  to ambient,  fill the container  and tubes  with fluid 
above  the minimum level used  to trigger a fill operati on; drain  the fluid down  to 
the minimum level;  tare the scale;  and perform  the linearity verification.   
(ii) If the container is rigid and not vented,  drain  the fluid down  to the minimum 
level; fill all tubes  attached  to the container to normal  operating  pressure;  tare 
the scale;  and perform the linearity verification. ”   
393 The Proposed  Amendments would  incorporate  the above  U.S. EPA amendments into 
California § 1065.307(d)(9) to harmonize  the California Code  of Regulations  with the 
recent  federal  regulation  changes,  with the following modifications:  
• In the first sentence, change the text “gravimetric PM balances, fuel mass 
scales, and DEF mass scales, ” to “gravimetric PM balances and fuel mass 
scales.”  
• In the second sentence, change the text “ fuel mass scales and DEF mass scales” 
to “fuel mass scales and mass scales for any other injected fluid .” 
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. The rationale for not 
including federal text related to Diesel Exhaust Fluid (DEF) is the same as that 
provided in the Global Amendments subsection in this section G, “Changes to 
References of Equipment Types, Engine Types, and Fuel .” The proposed c hanges are 
otherwise identical to the table text in the  same -numbered section of the federal 
Part 1065. 
§ 1065.340  
Purpose. The current regulations in § 1065.340 describe  the steps  to calibrate  flow 
meters  for diluted exhaust  constant  volume  sampling (CVS)  systems.  In addition  to the 
changes  described  in the “Updates  to Harmonize  with Amended  Federal  Text”  
subsection in this section  G, the Proposed  Amendments include  three  correctio ns to 
references:  
• In § 1065.340(e)(8) [re- lettered to (f)(8)], change the text “Repeat the steps in 
paragraphs (e)(6) and  (7) of this section” to “Repeat the steps in 
paragraphs  (f)(6) and (7) of this section.”  
• In § 1065.340(e)(10) [re- lettered to (f)(1)], change the text “ Repeat the steps in 
paragraphs (e)(6) through (9) of this section” to “ Repeat the steps in 
paragraphs  (f)(6) through (9) of this section.”  
• In § 1065.340(f)(8) [re- lettered to (h)(8)],  change the text “Repeat the steps in 
paragraphs ( f)(6) and (7) of this section ” to “ Repeat the steps in 
paragraphs  (h)(6) and (7) of this section .” 
The purpose of these changes is to update the references in the affected text to 
reflect the renumbering of paragraphs 1065.340(e) and 1065.340(f) in the current  text 
to 1065.340(f) and 1065.340(h), respectively, as described in the “ Updates to 
Harmonize  with Amended Federal Text” section.  
Rationale . These changes are necessary to provide consistency with the incorporation 
of recent amendments to federal regulatio ns into California’s SORE regulations and to 
provide clarity necessary to help ensure manufacturers reference the correct 
regulation subsections. The recent federal amendments renumber 1065.340(e) and 1065.340(f) to 1065.340(f) and 1065.340(h), respectivel y, and insert a new paragraph  
394 1065.340(e) that contains no numbered subsidiary paragraphs. These changes result in 
the need to also update the references to subsections within paragraphs 1065.340(e) 
[now re -lettered to 1065.340(f)] and 1065.340( f) [now re -lettered to 1065.340( h)]. 
§ 1065.350(e) [newly proposed subsection]  
Purpose. The current regulations in § 1065.350 specify  the steps to verify the amount  
of water interference after  initial NDIR analyzer  installation and after major  
maintenance, for use by manufacturers  that measure CO 2 using  an NDIR analyzer.  The 
current federal  regulations include the recent  addition  of a new subsection 
1065.350(e),  as follows:  
“(e) Exceptions.  The following exceptions apply:  
(1) You may omit this verification  if you can show  by engineering  analysis that 
for your CO 2 sampling system  and your emission calculation  procedures,  the 
H2O interference for your CO 2 NDIR analyzer  always  affects  your brake  specific 
emission results  within ±0.5%  of each  of the applicable standards . This 
specification  also applies  for vehicle  testing,  except  that it relates  to emission 
results in g/mile or g/kilometer.  
(2) You may use a CO 2 NDIR analyzer  that you determine  does  not meet  this 
verification,  as long as you try to correct the problem  and the measurement  
deficiency  does  not adversely  affect  your ability to show  that engines comply 
with all applicable  emission standards .” 
The Prop osed Amendments would incorporate this recent federal amendment into 
California § 1065.341 to harmonize the California Code of Regulations with the recent 
federal regulation changes, with one modification. The Proposed Amendments omit the sentence, “This specification also applies for vehicle testing, except that it relates 
to emission results in g/mile or g/kilometer. ” 
Rationale . These changes are necessary to provide consistency with recent changes 
made  to the corresponding provisions in the federal Part 1065, to improve clarity, and 
to prevent confusion. A reference to “vehicle testing” and standards in terms of g/mi or g/km in the amended federal text is omitted from the amended California text. The 
Proposed Amendments omit the sentence, “This specificat ion also applies for vehicle 
testing, except that it relates to emission results in g/mile or g/ki lometer,” because it 
is not relevant for California’s Part 1065. The  proposed changes are otherwise 
identical to the table text in the  same -numbered section o f the federal Part 1065. 
§§ 1065.365(d)(6), (e)(6), (f)(6), and (f)(10)  
Purpose. In paragraphs 1065.365(d)(6), (e)(6), (f)(6), and (f)(10), the Proposed 
Amendments change the text “vastly” to “significantly,” as indicated in underline and strikeout text in the following: “Use good engineering judgment to address the effect  
395 of hydrocarbon contamination if your point of introduction is vastly s ignificantly 
different from the point of zero/span gas introduction.”  
Rationale . This change is necessary to improve clarity, which is necessary to maintain 
the stringency of California emission regulations and the accuracy and robustness 
requirements for testing under this part. The introduction of an analytical gas for determining NMC cutter penetration fraction into the sample stream of a FID, rather 
than at the point where calibration gases are introduced, presents a risk that 
hydrocarbon deposited or condensed on the walls of the sample path due to previous operation may contaminate the analytical gas, artificially increasing measured hydrocarbon levels and potentially compromising the verification. Under conditions 
where this is likely to occur, steps must be taken to address the issue to avoid 
compromising the verification, in order to ensure the accuracy and representativeness of emission data gathered through testing under this part and thereby allow the expected emission reduction benefits of the SORE regulations to be quantified and 
realized. Due to variations in individual system design, the conditions where this is 
likely to occur, including sample introduction point, may vary between systems, and as such, the requirements must allow for appropriate analysis and decision- making by 
regulated parties performing this verification. However, the wording “vastly different” 
with regard to the introduction point may be interpreted as permitting h ydrocarbon 
contamination issues to be ignored in some cases where they in fact have a substantial 
effect on the result. The use of the term “significantly different” appropriately conveys the degree of accuracy and care required while allowing for the situation - and 
application- dependent nature of the necessary decision making. It is essential to 
satisfying the purpose of the regulations, and addressing the identified problem, that no such ambiguity exist and that hydrocarbon contamination of analytical gas es for 
NMC cutter penetration verification be addressed in any case where the arrangement 
of gas introduction points presents a significant risk of such contamination occurring.  
Subpart E – Engine Selection, Preparation, and Maintenance 
§ 1065.405(g) [new ly proposed paragraph]  
Purpose.  As described  in the “Global  Amendments”  subsection  of this section  G, the 
Proposed  Amendments add a new,  multi -part § 1065.405(g)  to harmonize  the 
California Code  of Regulations  with recent federal  regulation  changes.  The newly  
proposed  section  1065.405(g)  defines the components that are considered  to be part 
of the engine  for laboratory testing.  The Proposed  Amendments include  one 
modification  to § 1065.405(g)(1)(ii)  to make  the changes  specific  to California SORE  
regulation s, as indicated in underline  and strikeout  text in the following: 
“(ii) The component  is covered  by the applicable  Executive  Order  certificate  of 
conformity. For example, this criterion  would  typically exclude radiators  not 
described  in an application for certification. ”  
396 Rationale . These changes are necessary to provide consistency with (i.e., “harmonize”) 
recent changes made to the corresponding § 1065.405 in the federal Part 1054. The 
proposed changes to incorporate the new federal requirements would not result in 
cost impacts to manufacturers because they align CCR requirements with federal requirements that manufacturers already must follow. The proposed California -specific 
change to replace “certificate of conformity” with “Executive Order” is necessary to 
prevent confusion for the reader. CARB  uses the term “Executive Order” to refer to 
the certification document for an engin e family for sale  or lease for use in California.  
U.S. EPA uses  the term “certificate of conformity,” shortened to “certificate .” The 
proposed change ensures consistent use of California -specific terminology throughout 
the regulations. See the Global Amendments subsection, “ “EPA” to “CARB” Term 
Change, “Certificate of Conformity” to “Executive Order” Term Change,  and 
Improvements to References to Part  1054,” in this section G for additional 
explanation. 
Subpart F – Performing an Emission Test Over Specified Duty Cycles 
§ 1065.501(b) [newly proposed paragraph]  
Purpose. The current regulations in § 1065.501 specify  the procedures  to measure 
engine  emissions over a specified  duty cycle.  The current federal  regulations include 
the recent addition  of a new paragraph  501(b), as follows:  
 “Unless  we specify  otherwise,  you may control  the regeneration  timing  of 
infrequently  regenerated  aftertreatment devices  such as diesel  particulate  filters 
using  good  engineering  judgment . You may control  the regeneration timing  
using  a sequence of engine operating  conditions  or you may initiate 
regeneration with an external  regeneration  switch  or other  comma nd. This 
provision  also allows you to ensure that a regeneration event  does  not occur 
during  an emission test.”   
The Proposed Amendments would incorporate this recent federal amendment into California § 1065.501 to harmonize the California Code of Regulations with the recent 
federal regulation changes, with one modification. The Proposed Amendments delete 
the text “diesel” from the first sentence.  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding pro visions in the f ederal Part 1065. The rationale for not 
including federal text related to “ diesel ” particulate filter s is the same as that provided 
in the Global Amendments subsection in this section G, “Changes to References of 
Equipment Types, Engine Types, and Fuel .” Particulate filters pass exhaust through a 
filter that traps particulate matter and must be periodically regenerated by temporarily 
changing engine behavior to provide heat and oxygen to combust the accumulated 
particular matter and preve nt clogging. Particulate filters have become widespread for 
limiting PM emissions from diesel and other lean- burn compression -ignition engines, 
and as such, relevant provisions have been inserted into the federal Part 1065, which  
397 applies to engine testing in general. However, California’s Part 1065 does not apply to 
compression -ignition engines, such as those fueled with diesel fuel, and an explicit 
reference to “diesel” particulate filters presents issues substantially similar to those presented by reference to “diesel exhaust fluid,” and the reference is omitted based on the same reasoning. The proposed changes are otherwise identical to the table 
text in the  same -numbered section of the federal Part 1065. 
§ 1065.518 [newly proposed section]  
Purpose. Th e current federal regulations include the recent addition of a new section, 
1065.518, which provides instructions and considerations for engine preconditioning for testing. The Proposed Amendments would incorporate this recent federal amendment into Califo rnia Part 1065 to harmonize the California Code of Regulations 
with the recent federal regulation changes, with one modification. The Proposed Amendments omit the example related to diesel engines in the first sentence of § 1065.518(a), as indicated in str ikeout: “ This section applies for engines where 
measured emissions are affected by prior operation,  such as with a diesel engine that 
relies on urea -based selective catalytic reduction .”  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. The rationale for not 
including federal text related to diesel engines is the same as that provided in the 
Global Amendments subsection in this section G, “Changes to References o f 
Equipment Types, Engine Types, and Fuel .” The proposed changes are otherwise 
identical to the table text in the  same -numbered section of the federal Part 1065. 
§ 1065.530(c) [newly proposed subsection]  
Purpose. Th e current federal regulations include the recent addition of a new 
subsection 1065.530(c), which provides instructions for starting and running each test interval. The Proposed Amendments would incorporate this recent federal amendment into California Part 1065 to harmonize the California Code of Regulations 
with the recent federal regulation changes, with one modification. In paragraph 
1065.530(c), the Proposed Amendments omit the federal text, “For example, 40 CFR 
part 1033 specifies a different way t o perform discrete -mode testing,” because 40 
CFR part 1033 refers to control of emissions from locomotives.  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. The om ission of the 
federal regulation text related to locomotives engines  is necessary to prevent 
confusion because the SORE regulations to not apply to locomotive engines regulated 
under 40 CFR part 1033. The rationale for this omission is the same as that pro vided in 
the Global Amendments subsection in this section  G, “Changes to References of 
Equipment Types, Engine Types, and Fuel .” The proposed changes are otherwise 
identical to the text in the same -numbered section of the federal Part 1065 .  
398 § 1065.543 [newly proposed section]  
Purpose. The current federal regulations include the recent addition of a new section, 
1065.543, which provides instructions for carbon balance error verification as an 
alternative to linearity verification or propane checks for certai n test equipment. The 
Proposed Amendments would incorporate this recent federal amendment into 
California Part  1065  to harmonize the California Code of Regulations with the recent 
federal regulation changes, with one modification. In the third sentence in paragraph 
1065.543(a), the Proposed Amendments change the corresponding federal text “ and 
optionally DEF or other fluids ” to “any other fluids injected into the exhaust, if 
applicable.”  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. Omitting the federal 
text related to Diesel Exhaust Fluid (DEF) is necessary to prevent confusion because 
the California SORE regulations do not apply to diesel engines produced during the 
2000 and later model years. The rationale for this omission is the same as that provided in the Global Amendments subsection in this section G, “Changes to 
References of Equipment Types, Engine Types, and Fuel .” The proposed changes ar e 
otherwise identical to the text in the  same -numbered section  of federal Part 1065.  
Subpart G – Calculations and Data Requirements  
§ 1065.643 [newly proposed section]  
Purpose. The current federal regulations include the recent addition of a new section, 
1065.643, which specifies provisions for carbon balance error verification calculations 
to support the newly added §1065.543.  The Proposed Amendments would 
incorporate this recent federal amendment into California Part 1065  to harmonize the 
California Code  of Regulations with the recent federal regulation changes, with two 
modifications. In paragraph 1065.643(a), the Proposed Amendments omit text related to DEF in the corresponding amended federal text, and change the subscript “DEF” in the example calculation terms to the subscript “inj” to refer to other injected fluids.  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. Omitting the federal 
text related to DEF i s necessary to prevent confusion because the California SORE 
regulations do not apply to diesel engines produced during the 2000 and later model 
years . The rationale for this omission is the same as that provided in the Global 
Amendments subsection in this  section  G, “Changes to References of Equipment 
Types, Engine Types, and Fuel .” The proposed changes are otherwise identical to the 
table text in the  same -numbered section of the federal Part 1065 .  
§ 1065.650(c)(3)  
Purpose. The current regulations in § 1065.650(c)(3)  provide instructions for collecting 
a batch sample , along with equations for calculating emission mass and example  
399 calculations,  from a varying  exhaust flow rate  in subsection (3)(i) and a constant 
exhaust flow rate in subsection (3)(ii). The Proposed Amendments add the time unit 
“s” (seconds) for the example calculation in subsection (3)(i) as indicated in the 
following text in underline, “ Δt = 1/5 = 0.2 s .” The Proposed Amendments add the 
emission mass unit “g” (grams) for the example calculation in subsection (3)(ii) as 
indicated in the following text in underline, “ mPM = 144.0·10−6·57.692·1200  g.” 
Rationale . These change s are necessary to correct an oversight in the federal 
regulations and to provide complete example calculation s in order  to prevent 
confusion for testers.  
§ 1065.655(c)  
Purpose. The current regulations in § 1065.655 specify  provisions  for use of chemical  
balances  of fuel, intake  air, and exhaust  to calculate  flows,  the amount  of water in their 
flows,  and the wet concentrati on of constituents  in their flows.  Subsection  1065.655(c)  
describes the chemical  balance  procedure.  The current federal  regulations include the 
following recent  amendments  made  by U.S. EPA to the unnumbered  initial paragraph  
of subsection 1065.655(c),  as indicated  by underline and strikeout  text:  
“… You must  also use your fuel's fuel mixture’s  atomic hydrogen -to-carbon  
ratio,  α, oxygen -to-carbon  ratio,  β, sulfur -to-carbon  ratio,  γ, and 
nitrogen -to-carbon  ratio,  δ; you may optionally  account for diesel  exha ust fluid 
(or fluids injected  into the exhaust ), if applicable . You may measure calculate  α, 
β, γ, and δ or you may based  on measured  fuel composition  or based  on 
measured  fuel and diesel  exhaust  fluid (or other  fluids  injected  into the exhaust)  
compositio n together , as described  in paragraph  (e) of this section.  You may 
alternatively use any combination  of default  values and measured  values for a 
given  fuel as described  in § 1065.655(d)  paragraph  (e) of this section . Use the 
following steps to complete  a chemical  balance:  …” 
The Proposed  Amendments would  incorporate  the above  U.S. EPA amendments into 
California § 1065.655(c ) to harmonize  the California Code  of Regulations with the 
recent  federal  regulation  changes,  with the following modifications  to the amended  
federal  text: 
• In the first sentence, change the federal text “ you may optionally account for 
diesel exhaust fluid (or fluids injected into the exhaust )” to “ you may optionally 
account for fluids injected into the exhaust .” 
• In the second sentence, change the federal text “or based on measured fuel 
and diesel exhaust fluid (or other fluids injected into the exhaust) comp osition 
together ” to “or based on measured fuel and fluids injected into the exhaust 
composition together .” 
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. The  modifications to 
the federal text, omitting the federal text related to diesel exhaust fluid, are necessary  
400 to prevent confusion because the California SORE regulations do not apply to diesel 
engines produced during the 2000 and later model years. The rat ionale for this 
omission is the same as that provided in the Global Amendments subsection in this section  G, “Changes to References of Equipment Types, Engine Types, and Fuel .” The 
proposed changes are otherwise identical to the text in the  same -numbered s ection  of 
the federal Part 1065.  
§ 1065.655(e) [newly proposed subsection]  
Purpose. The current federal  regulations  include the recent  addition  of a new 
subsection 1065.655(e)  that provides  the procedure  to determine  fuel and diesel  
exhaust  fluid composition.  The Proposed  Amendments  would  incorporate  this recent  
federal  amendment  into California Part 1065  to harmonize  the California Code  of 
Regulations with the recent  federal  regulation  changes,  with four modifications: 
• Change the text related to “ diesel exhaust fluid” in the corresponding 
amended federal text to  “injected fluid,” “other injected fluid,” or “any fluid 
injected into the exhaust,” as appropriate, throughout this subsection.   
• Change the text “You may also assume that sulfur and nitrogen have a zero 
concentration for all fuels except residual fuel blends” in the corresponding amended federal text  in paragraph (e)(1)(i) to “You may also assume that sulfur 
and nitrogen have a zero concentration for all fuels used for testing under this part.”  
• In Table 1 of 1065.655 (e)(5), omit the entry for “Diesel exhaust fluid” in the 
corresponding amended federal text.   
• Change the text related to diesel engines in an example in the corresponding 
federal text  in paragraph (e)(3), as indicated in underline and strikeout in the 
following: “Application of average values from a batch measurement generally 
applies to situations where one fluid is a minor component of the total fuel 
mixture, for example dual -fuel engines and flexible -fuel engines with diesel pi lot 
injection, where the diesel pilot fuel mass is less than 5 % of the total fuel mass 
and diesel exhaust fluid injection; consistent with good engineering judgment . 
Rationale . These changes are necessary to provide consistency with recent changes 
made to  the corresponding provisions in the f ederal Part 1065. Omitting the federal 
text related to diesel exhaust fluid and diesel engines is necessary to prevent 
confusion because the California SORE regulations do not apply to diesel engines produced during th e 2000 and later model years. The rationale for this omission is the 
same as that provided in the Global Amendments subsection in this section G, 
“Changes to References of Equipment Types, Engine Types, and Fuel .” Similarly, 
residual fuel blends are unsuitable for use in spark -ignition engines, and a reference to 
special provisions relating to calculations involving a fuel unsuitable for SORE, which are by definition spark -ignition, and any explicit reference to diesel engines, is not 
necessary. The proposed changes are otherwise identical to the text in the  same -
numbered section of the federal Regulations  Part 1065.    
401 § 1065.667(d) [newly lettered paragraph]  
Purpose. The current regulations in § 1065.667 specify the procedure to determine 
the mass of background emissions to subtract from (i.e., correct) a diluted exhaust 
sample . The current federal Part 1065.667 includes a suite of recent amendments  
made by U.S.  EPA, which include moving much of the federal text form ally in  
paragraph 1065.667(c) to a new paragraph 1065.667(d).  As described in the Global 
Amendments subsection, “Updates to Harmonize with Amended Federal Text ,” the 
Proposed Amendments would incorporate the recent federal amendments into 
California Part  1065 to harmonize the California Code of Regulations with the recent 
federal regulation changes.  
The Proposed Amendments include one modification to the amended federal text. In  
the newly lettered  paragraph 1065.667(d), U.S. EPA changed the text “You may 
determine the total flow of dilution air from the total flow of diluted exhaust and a 
chemical balance of the fuel, intake air, and exhaust as described in §1065.655” to “You may determine the total flow of dilution air from the measured dilute exhaust 
flow and a chemical balance of the fuel, DEF, intake air, and dilute exhaust as 
described in §1065.655. ” The Proposed Amendments change the text “DEF” in the 
corresponding amended federal text to “any injected fluids.”  
Rationale . These changes are necessary t o provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. Omitting the federal 
text “DEF” is necessary to prevent confusion because the California SORE regulations do not apply to diesel engines produced durin g the 2000 and later model years. The 
rationale for this omission is the same as that provided in the Global Amendments 
subsection in this section G, “Changes to References of Equipment Types, Engine 
Types, and Fuel .” The proposed changes are otherwise identical to the table text in 
the same -numbered section of the federal Part 1065 . 
Subpart H  – Engine Fluids, Test Fuels, Analytical Gases and Other Calibration 
Standards 
§ 1065.701(a)  
Purpose. The current regulations in § 1065.701(a)  specify  requirements for certification  
test fuel used  for emission testing . The Proposed  Amendments  include three  changes 
to this subsection as follows:   
• In paragraph  1065.701(a)(1), the Proposed Amendments change the reference 
to “California Exhaust Emission Standards and Test Procedures for 2001 – 2014 
Model Passenger Cars, Light Duty Trucks, and Medium -Duty Vehicles” to 
“California 2001 t hrough 2014 Model Criteria Pollutant Exhaust Emission 
Standards and Test Procedures and 2009 t hrough 2016 Model Greenhouse Gas 
Exhaust Emission Standards and Test Procedures for Passenger Cars, Light -Duty 
Trucks, and Medium -Duty Vehicles ,” to correctly reflect the current title, and  
402 change the text “[insert latest  amendme nt date]” to “ December  6, 2012,” to 
replace the placeholder text with the most recent amendment date.  
• In paragraph  1065.701(a)(2), the Proposed Amendments change the 
abbreviation “CCR” to “California Code of Regulations ” and add “California 
Code of Regulations” where it is  implied between Title 13 and a section 
number in two  places.  
• In paragraph  1065.701(a)(2), the Proposed Amendments change the text 
“adopted [insert adoption date]” to “as last amended December 19, 2018 ,” to 
replace the placeholder text with the adoption date for the reference to 
“California 2015 and Subsequent Model Criteria Pollutant Exhaust Emission 
Standards and Test Procedures and 2017 and Subsequent Model Greenhouse Gas Exhaust Emission Standards and Test Procedures for Passenger Cars, Light- Duty Trucks, and Medium -Duty Vehicles”  
The purpose of making these changes at these points in the text is to establish 
consistency and currency in references to the California Code of Regulations.  
Rationale . These changes are necessary to specify  the exact body of regulations to 
which these subsections refer and to satisfy the clarity requirements for California Administrative Law. The current regulations use “CCR” and “Title 13” without 
elaboration in this section, while a full reference to the “California Code of Regulations” is used in others.  Although the existing references are sufficient to 
identify the regulations, the use of different forms of reference could confuse parties subject to the regulations, as it may create the impression that these are different references.  It is essential to satisfying the purpose of the regulations and addressing 
the identified problem that they be understandable to the regulated parties, including 
where references are made to other regulations , and that there is no real or perceived 
ambiguity in such references.  
§ 1065.70 1(f) 
Purpose. The current regulations in § 1065.701(f ) specify  requirements for test fuels 
used  for service  accumulation  and aging.  The Proposed  Amendments include two 
amendments  to this section  as follows:  
• First, the Proposed Amendments delete the followi ng text from paragraph 
1065.701 (f)(1)(i): “ As an alternative, the certification test fuels specified under 
either §1054.501(b)(2)(ii)(A) or §1054.501(b)(2)(ii)(B), as applicable, may be used 
for engine service accumulation and aging. ”  
• Second, in paragraph  1065.701(f)(2)(i), the Proposed Amendments change the 
text “Liquefied petroleum gas meeting the ASTM D1835 (11/10/1997) or NGPA 
HD-5 (1970) specifications must be used for service accumulation.” to 
“Liquefied petroleum gas meeting the ASTM D1835 (5/1/2020) specification or the HD -5 grade specification per GPA 2140 2017 edition (also known as “NGPA  
403 HD-5”) must be used for service accumulation. ASTM D1835 (5/1/2020) and 
GPA 2140 (2017) are incorporated herein by these references.”  
Rationale. The rationales  for the Proposed  Amendments to § 1065.701(f)  are as 
follows:  
• The first proposed change is necessary to provide consistency with Proposed 
Amendments to California’s Part 1054, and prevent confusion or regulatory 
conflict. The Proposed Amendments delete the entire subsection 
1054.5 01(b)(2)(ii) to harmonize California’s Part  1054 with recent federal 
Part 1054 amendments, which deleted the corresponding federal provisions, as 
described in the Global Amendments subsection, “ Updates to Harmonize with 
Amended Feder al Text ,” in section  F of this chapter. Continuing to have 
references in the text of California’s Part 1065 that refer to provisions that no 
longer exist could create confusion for regulatory parties or impose conflicting 
regulatory requirements. It is essential to satisfying the purpose of the 
regulation and addressing the identified problem that no such ambiguity or 
conflict exist within the regulatory text.  
• The second proposed change to document references is necessary to satisfy the requirements of Cali fornia Administrative Procedure Act regulations (Title  1, 
CCR, § 16) regarding clarity, while preserving the intent of the current 
regulatory text to the extent possible. The text “NGPA  HD-5”in the current 
regulation refers to the specifications for grade HD -5 liquefied petroleum gas 
(propane), published in the standard GPA 2140, “Liquefied Petroleum Gas Specifications and Test Methods,” by GPA Midstream Association, formerly the Gas Processors Association and previously the Natural Gas Processors 
Associati on, headquartered in Tulsa, Oklahoma. This document was originally 
adopted in 1931, and was revised several times, including in 1970, the version 
to which the current regulation refers, as well as in several other years between 1970 and the adoption of Cal ifornia’s Part 1065 in 2012. The reasons for 
selecting the 1970 version, which was multiple versions out of date at the time 
of the original rulemaking, are not elucidated in the available rulemaking record 
for the 2012 adoption. CARB staff has been unable to obtain a copy of the 1970 
version of this publication to review, or to make available in the record for this rulemaking as required by California Administrative Law. CARB staff has however obtained copies of both the 1997 revision and of the latest rev ision 
published in 2017,
rr, ss and observed that the HD -5 specification has not 
changed between these revisions; as such, it may be reasonably inferred that the 1970 version rather than a more recent one, was likely specified in the 2012 
                                            
rr GPA Midstream Association. 2017. GPA  Midstream Standard 2140- 17, Liquefied Petroleum Gas 
Specifications and Test Methods. Adopted as Recommended Procedures 1931, revised 2017.  
ss Gas Processors Association. 1997. GPA  Standard 2140- 97, Liquefied Petroleum G as Specifications 
and Test Methods. Adopted as Recommen ded Procedures 1931, revised 1997.   
404 adoption because it reflected the last actual revisions to the HD -5 propane 
specification at that time. If this is the case, then specifying the 2017 revision 
instead will allow CARB to fulfill the reference requirements in California 
Administrative Law without otherwise affe cting regulated parties. It is essential 
to satisfying the purpose of this regulation and addressing the identified problem that it satisfy the requirements of California Administrative Procedure Act. 
In addition,  the proposed  change from  “ASTM  D1835 (11/10/1997)”  to “ASTM  
D1835  (5/1/2020)”  is necessary  to ensure manufacturers  use the most  recently 
updated industry standard,  ASTM  D1835 – 20, Standard  Specification  for 
Liquefied  Petroleum  (LP) Gases,  approved  May 1, 2020  (“ASTM  D1835”).  CARB  
staff evaluated  the revisions made  to ASTM  D1835  between  1997  and 2020 and 
has determined  that the revisions  do not relax  certification  standards  or testing  
procedures  and do not adversely  affect  industry. CARB  staff determined  that 
this change will not increase industry  costs  and may decrease them,  as the 2020 
revision  does  not introduce  new requirements and allows additional  testing  
methods  to be used  to demonstrate  certain  properties  of the product,  allowing 
labs to select  the method  which  is most  cost-effective  given  their equipment  
and practices.  Also, industry requested  that CARB  reference the most  recent  
versions of industry  standards  documents  to prevent  potential  confusion  and 
the additional  cost of maintaining and referencing  multiple editions, given  
manufacturers  typically use the most  recent editions of standards  documents  in 
addition  to any earlier editions required  by regulations.  
§ 1065.790(b)  
Purpose. The current regulations in § 1065.790 provide  specifications  for mass  
standards.  Paragraph  1065.790(b)  currently specifies,  “Dynamometer calibration  
weights.  [Reserved] ”, which  reflects  the text in the corresponding  federal  
Part 1065.790(b)  in June  2011.  The current federal  regulations  include the following 
recent  amendments made  by U.S. EPA to paragraph  (b), as indicated by underline and 
strikeout  text: 
“(b) Dynamometer, fuel mass  scale,  and DEF mass  scale  calibration  weights.  
[Reserved]  Use dynamometer and mass  scale  calibration  weights  that are 
certified  as NIST- traceable  within 0.1%  uncertainty.  Calibrat ion weights  may be 
certified  by any calibration  lab that maintains  NIST- traceability. ” 
The Proposed  Amendments would  incorporate  the above  U.S. EPA amendments into 
California § 1065.790(b)  to harmonize  the California Code  of Regulations  with the 
recent  federal regulation  changes,  with two modifications:   
• First, the Proposed Amendments change the text “Dynamometer, fuel mass scale, and DEF mass scale” to “Dynamometer and fuel mass scale” in the first sentence.   
405 • Second, the Proposed Amendments change the text “ NIST ” to “SI” in the 
second and third sentences. This proposed modification would change the 
federal Part 1065  requirement to use NIST -traceable mass standards to instead 
allow the use of SI traceable mass standards through NIST or another member of the CIPM  MRA . 
The purpose of these changes is to harmonize California’s Part 1065 with subsequent 
amendments to of the  federal Part 1065, except as necessary to uphold the stringency 
of California emission standards, maintain consistency with existing California regulation, or prevent confusion, while establishing consistency with current accepted 
metrological practice and establishing that reference value traceability may be through NIST or equivalent national or international standards bodies, rather than NIST alone, without special permission.  
Rationale . These changes are necessary to provide consistency with recent changes 
made to the corresponding provisions in the f ederal Part 1065. The omission of the 
federal text related to the DEF  mass scale is necessary to prevent confusion because 
the California SORE regulations do not apply to diesel engines produced during the 
2000 and later model years. The rationale for not including federal text related to DEF is the same as that provided in the Global Amendments subsection in this section G, 
“Changes to References of Equipment Types, Engine Types, and Fuel .” The rationale  
for requiring  SI-traceable standards rather than the federal requirement for NIST -
traceable standards is the same as that provided in the Global  Amendments 
subsection, “ Calibration Requirements Change.” The proposed changes are otherwise 
identical to the table text in the  same -numbered section of the federal Part 1065.  
Subpart K – Definitions and Other Reference Information  
§ 1065.1001  
Proposed Changes to Make Adopted Federal Regulations Specific to California 
SORE Regulations  
Purpose. Section  1065.1001 specifies the definitions that apply  to Part 1065.  The 
Proposed  Amendments include the following changes in addition  to the changes 
described  in the Global  Amendments section  of this section  G: 
• First, in the unnumbered initial paragraph, the Proposed Amendments delete 
the reference to Title 40, Code of Federal Regulations, Part 1068.  
• Second, the Proposed Amendments add a definition for the term “A ct” that 
specifies:  
“Act means the United States Clean Air Act, as amended 
November 1 5, 1990, 42 U.S.C. 7401 -7671q.”  
• Third, in the definition for “Engine,” the Proposed Amendments change the text “Engine as used in this part, refers to small off -road engin e” to “Engine as  
406 used in this part, refers to a small off -road engine as defined in Title 13, 
California Code of Regulations, § 2401. ” This Proposed Amendment corrects a 
grammatical error by adding “a” between “to” and “small,” and adds a 
reference to the relevant section of the California Code of Regulations for the definition of engine.  
• Fourth, the Proposed Amendments delete the definition for “Revoke” which 
references the meaning given in Title 40, Code of Federal Regulations, 
Part 1068.  
• Fifth, in the definition for “Standard -setting part,” the Proposed Amendments 
change the text “the part in the Code of Federal  Regulations that defines 
emission standards” to “ the part in the Code of California Regulations that 
defines emission standards.”  
The purpose of these proposed changes is to clarify that California regulations and 
definitions, not federal regulations and definitions, are those that apply under this 
part, except to the extent that definitions in harmonized federal text rely on federal 
statutory definitions, and in one case to correct a grammatical error.  
Rationale . These cha nges are necessary to  correct an oversight that occurred at the 
time certain  federal regulations were incorporated into the California Code of 
Regulations, and to improve clarity and regulatory certainty. P art 1065 was adopted 
into the California Code of Regulations in 2012, and consisted primarily of text 
adopted from the U.S. EPA  regulation in Title 40, Code of Federal Regulations, 
Part 1065, as of June 28, 2011, with changes to address California’s specific 
regulations. The previously adopted federal text referred to the relevant portions of 
the Code of Federal Regulations defining relevant terms and requirements as applied to testing under this part. However, the Part 1065 ado pted into the California Code of 
Regulations applies specifically in the context of SORE as defined in California 
regulation, and as such, where California has adopted California -specific definitions or 
other regulatory text that differ from the federal te xt, California’s definitions and 
regulations are the ones that apply. References to federal regulation that are currently 
included in the California Part  1065 create potential confusion for regulated parties 
and may be interpreted as creating a regulatory conflict. It is essential to satisfying the purpose of this regulation and addressing the identified problem that there be no such confusion, or real or perceived conflict, where California definitions take precedence. However, the federal text as adopted,  and as amended to harmonize 
with updates to the federal regulation, relies on definitions given in the United States Clean Air Act, which as federal legislation rather than regulation applies in this context; an explicit reference is included for clarity.  Finally, California Administrative 
Procedure Act regulations (Title  1, CCR, § 16(a)(4)) requires that regulations be free of 
grammatical errors, which may create confusion or ambiguity or undermine the perceived authoritativeness of the regulation text. It is essential to satisfying the purpose of this regulation and addressing the identified problem that there be no such real or perceived ambiguity or error in language use in the regulatory text.   
407 Proposed Change to Add a Definition for “Good Engineering J udgment”  
Purpose. The Proposed  Amendments add a definition for “good  engineering  
judgment”  to § 1065.1001 as follows:  
“Good  engineering  judgment  means  decisions or determinations,  relating to 
any aspect  of testing  under  this part,  which  are based  on and consistent  with 
sound  and well-established  principles of science  and engineering,  accepted  
best practices  as they apply  to the specific type of testing  and context  under  
consideration,  and all other  relevant  information,  so as to ultimately ensure that 
emission measurements and other  data collected  under  this part accurately 
represent  the engine’s  actual  emissions during  the testing  and are 
representative  of the engine family’s  emissions in typical  operation  by ultimate  
purchasers . Good  engineering  judgment,  as defined  here,  should  be used  in 
making all decisions or determinations  regarding testing  under  this part.  Explicit 
instructions,  elsewhere  in this part,  to employ  good  engineering  judgment  in 
making certain  decisions or determinations  should  not be construed  as 
permitting  other  decisions or determinations  to be made  without  employing  it.” 
The purpose of this proposed change is to clarify the meaning of the term and its use 
in decision making  to ensure the generation of accurate and representative SORE 
emission data.  
Rationale . This change is necessary to  correct an oversight that occurred at the time 
federal Part 1065 regulations were incorporat ed into the California Code of 
Regulations, and to improve clarity and regulatory certainty. Current California SORE regulations do not contain a definition of the term “good engineering judgment,” but 
the term is frequently used in federal Part  1065 regulations adopted into the California 
SORE regulations in 2012 and in recent federal regulation amendments that would be 
incorporated by the Proposed Amendments. Title 40, Code of Federal Regulations, Part 1068, specifies the meaning of this term for use in f ederal regulatory text such as 
Title 40, Code of Federal Regulations, Part 1065, and provides standards of review and an associated hearing process. The federal regulations also contain instructions that good engineering judgment be employed in all federal  testing, not only where 
explicitly referenced. Because these portions of Part 1068 have not been incorporated into the California SORE regulations, it is necessary to add a definition of “good engineering judgment” to California Part 1065. A California -specific definition of the 
term “good engineering judgment” and specific instructions to apply it in all decision-
making regarding testing under California Part 1065, rather than only where called 
out, are necessary to ensure that the expected emission reduc tion benefits from the 
California SORE regulations are actually and measurably achieved.  
§ 1065.1010  
Purpose. Section 1065.1010 provides a list of reference documents that have been 
incorporated by reference into Part 1065. Because the federal Part  1065.1010 was 
extensively amended and reformatted subsequent to CARB’s adoption of California’s  
408 Part 1065, the Proposed Amendments replace the entirety of §  1065.1010 with text 
formatted to mirror the current organization of the federal Part 1065.1010. The newly 
proposed list omits reference documents listed in the federal  Part 1065.1010 that are 
referenced in federal text not adopted by CARB and adds “[Reserved]” in their place 
to preserve the continuity of the document numbering and consistency with numbering of  similar federal references.  
The Proposed  Amendments add the following new entries  to the indicated  
subsections:  
• Subsection 1065.1010(b): ASTM material  
(28) ASTM  D4629 – 12, Standard  Test Method  for Trace  Nitrogen  in Liquid 
Petroleum  Hydrocarbons  by Syringe/Inlet  Oxidative Combustion  and 
Chemiluminescence  Detection,  approved  April  15, 2012 (“ASTM  D4629”),  cited  
in § 1065.655(e).  
(33) ASTM  D5291 – 10, Standard  Test Methods for Instrumental  Determination  
of Carbon,  Hydrogen,  and Nitrogen  in Petroleum  Products  and Lubricants,  
approved  May 1, 2010  (“ASTM  D5291”),  cited  in § 1065.655(e).  
(35) ASTM  D5599 – 00 (Reapproved 2010),  Standard  Test Method  for 
Determina tion of Oxygenates  in Gasoline by Gas Chromatography and Oxygen  
Selective  Flame  Ionization  Detection,  approved  October  1, 2010 (“ASTM  
D5599”),  cited  in §§ 1065.655(e).  
(36) ASTM  D5762 – 12, Standard  Test Method  for Nitrogen  in Petroleum  and 
Petroleum  Produ cts by Boat -Inlet Chemiluminescence,  approved  April  15, 2012  
(“ASTM  D5762”),  cited  in § 1065.655(e).  
(40) ASTM  D6348 – 12
ε1, Standard  Test Method  for Determination  of Gaseous 
Com pounds  by Extractive  Direct Interface  Fourier  Transform  Infrared  (FTIR)  
Spectroscopy,  approved February  1, 2012  (“ASTM  D6348”),  cited  in 
§§ 1065.266(b)  and 1065.275(b).  
(47) ASTM  F1471  – 09, Standard  Test Method  for Air Cleaning  Performance  of a 
High-Efficiency Particulate  Air Filter System,  approved  March  1, 2009  (“ASTM  
F1471”),  cited  in §1065.1001.  
(48) ASTM  D1835 – 20, Standard  Specification  for Liquefied Petroleum (LP) 
Gases,  approved  May 1, 2020  (“ASTM  D1835”),  cited  in §1065.701.  
• Subsection 1065.1010(c): California Air Resources Board material  
(3) California 2001 through 2014 Model  Criteria  Pollutant Exhaust  Emission 
Standards  and Test Procedures  and 2009 through 2016 Model  Greenhouse Gas 
Exhaust  Emission Standards  and Test Procedures  for Passenger  Cars,  Light- Duty  
409 Trucks,  and Medium -Duty Vehicles,  amended  December  6, 2012,  cited  in 
§ 1065.701.   
(4) California 2015 and Subsequent  Model  Criteria  Pollutant Exhaust  Emission 
Standards  and Test Procedures  and 2017 and Subsequent  Model  Greenhouse  
Gas Exhaust  Emission Standards  and Test Procedures  for Passenger  Cars,  
Light- Duty Trucks , and Medium -Duty Vehicles,  amended  December  19, 2018,  
cited  in § 1065.701.  
• Subsection 1065.1010(e): ISO material  
(16) ISO 8178- 1:2020(E) , Reciprocating  internal  combustion  engines — Exhaust  
emission measurement  — Part 1: Test-bed measurement  systems of gaseous  
and particulate  emissions,  published  June  2020,  (“ISO 8178 -1”), cited  in 
§ 1065.601(c)(1).  
• Subsection 1065.1010(g): SAE International material  
(2) SAE J1151,  Methane Measurement  Using  Gas Chromatography,  stabilized 
September  2011,  cited  in §§1065.267 (b) and 1065.750(a)(2)(i).  
The Proposed Amendments add the following new subsections and references:  
(h) U.S. EPA Material.  The following documents  are available  from  the United  
States  Environmental  Protection  Agency  Emissions Measurement  Center,  109 
TW Alexander  Drive,  Research Triangle  Park,  NC 27709,  (202)  566-0556,  or 
www.epa.gov:  
(1) Title 40, Code  of Federal  Regulations,  Part 63, Appendix  A—Test  Methods,  
Test Method  320—Measurement  of Vapor  Phase Organic  and Inorganic 
Emissions by Extractive  Fourier  Transform  Infrared  (FTIR)  Spectroscopy,  last 
amended  December  2, 2020, cited  in §1065.266 and §1065.275.  
(i) GPA Midstream Association  Material:  The following documents  are available 
from  GPA Midstream Association,  6060 American  Plaza,  Suite 700, Tulsa,  
Oklahoma 74135,  (918)  493-3872:  
(1) GPA Midstream Standard  2140- 17, Liquefied Petroleum  Gas Specifications  
and Test Methods (“GPA  2140”),  revised  2017,  cited  in § 1065.701.  
Rationale . These changes are necessary to harmonize California’s Part 1065 with 
subsequent amendments to the  federal  Part 1065 , provide citations only for those 
references cited in California Part  1065, provide citations for references cited in 
California Part 1065 that are not cited in the federal Part 1065, and fulfill the 
requirements of California Administrative Procedure Act regulations (Title  1, CCR, 
§ 16(a)(6 )) to provide references with citation styles that clearly identify published 
material cited in the regulation . The changes listed are otherwise identical to the 
changes in the same -numbered section  of the federal Part 1065 due to amendments  
410 adopted subsequent to  June 2011 ,tt and are proposed  for the reasons described in 
the Global Amendments subsection, “ Updates to Harmonize with Amended Federal 
Text,” in this section G of this chapter.  
XII. References  
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XIII. Appendices  
Appendix A: Proposed Amendments to the Small Off -Road Engine Exhaust 
Emission Regulations, California Code of Regulations, Title 13, Division 3, 
Chapter 9. Off -Road Vehicles and Engines Pollution Control Devices, 
Article  1. Small Off -Road Engine s  
 Appendix B: Proposed Amendments to the Small Off -Road Engine Evaporative 
Emission Regulations, California Code of Regulations, Title 13, Division 3, 
Chapter 15. Additional Off -Road Vehicles and Engines Pollution Control 
Requirements, Article 1.  Evaporative Emission Requirements for Off -Road 
Equipment  
 Appendix C: Proposed Amendments to Small Off -Road Engine Evaporative 
Emissions Test Procedure, TP -901, Test Procedure for Determining 
Permeation Emissions from Small Off -Road Engine Fuel Tanks  
 Appendix D: Proposed Amendments to Small Off -Road Engine Evapo rative 
Emissions Test Procedure, TP -902, Test Procedure for Determining 
Evaporative Emissions from Small Off -Road Engines  
 Appendix E: Proposed Amendments to Small Off -Road Engine Evaporative 
Emission Control System Certification Procedure, CP -902, Certifi cation 
Procedure for Evaporative Emission Control Systems on Small Off -Road 
Engines    
439  
Appendix F: Proposed Amendments to the California Exhaust Emission 
Standards and Test Procedures for New 2013 and Later Small Off -Road 
Engines; Engine- Testing Procedures (Part 1054)  
 Appendix G: Proposed Amendments to the California Exhaust Emission 
Standards and Test Procedures for New 2013 and Later Small Off -Road 
Engines; Engine- Testing Procedures (Part 1065)   
 Appendix H: Final Environmental Analysis for the Revised Proposed 2016 State 
Strategy for the State Implementation Plan  
 Appendix I: Standardized Regulatory Im pact Asses sment with Department of 
Finance C omments  
 Appendix J: Pre-Rulemaking Workshop Notices and Email Soliciting 
Alternatives