Exhaust Emission Standards
grams per brake horsepower-hour
[grams per kilowatt-hour]
Calendar Year | Engine Class(1) | Hydrocarbon plus Oxides of Nitrogen(2) | Hydrocarbon(2) | Carbon Monoxide | Oxides of Nitrogen | Particulate |
1995 | I | 12.0 | -- | 300 | -- | 0.9(3) |
II | 10.0 | -- | 300 | -- | 0.9(3) | |
III(4) | -- | 220 | 600 | 4.0 | -- | |
IV(4) | -- | 180 | 600 | 4.0 | -- | |
V(4) | -- | 120 | 300 | 4.0 | -- | |
1996 to 1999 | I | 12.0(5) | -- | 350 | -- | 0.9(3) |
II | 10.0(5) | -- | 350 | -- | 0.9(3) | |
III(4) | -- | 220(5) | 600 | 4.0(5) | -- | |
IV(4) | -- | 180(5) | 600 | 4.0(5) | -- | |
V(4) | -- | 120(5) | 300 | 4.0(5) | -- |
Exhaust Emission Standards for Spark-Ignition Engines
grams per brake horsepower-hour
[grams per kilowatt-hour]
Model Year | Engine Class | Durability Periods (hours) | Hydrocarbon plus Oxides of Nitrogen(2) | Carbon Monoxide | Particulate |
2000-2001(5) | 50/125/300 | 54 | 400 | 1.5(4) | |
0-65 cc, inclusive | [72] | [536] | [2.0] | ||
NA | 12.0 | 350 | NA | ||
> 65 cc--< 225 cc | [16.1] | [467] | NA | ||
NA | 10.0 | 350 | NA | ||
>=225 cc | [13.4] | [467] | NA | ||
2002-2004(5) | 50/125/300 | 54 | 400 | 1.5(4) | |
0-65 cc, inclusive | [72] | [536] | [2.0] | ||
> 65 cc--< 225 cc | 125/250/500 | 12.0 | 410 | NA | |
Horizontal-Shaft Engine | [16.1] | [549] | NA | ||
> 65 cc--< 225 cc | NA | 12.0 | 350 | NA | |
Vertical-Shaft Engine | [16.1] | [467] | NA | ||
>=225 cc | 125/250/500 | 9.0 | 410 | NA | |
[12.0] | [549] | NA |
Exhaust Emission Standards for Spark-Ignition Engines
(grams per kilowatt-hour)
Model Year | Displacement Category | Durability Periods (hours) | Hydrocarbon plus Oxides of Nitrogen(2)(6) | Carbon Monoxide | Particulate |
2005 through 2023 | < 50 cc | 50/125/300 | 50 | 536 | 2.0(4) |
50-80 cc, inclusive | 50/125/300 | 72 | 536 | 2.0(4) | |
2005 | > 80 cc--< 225 cc Horizontal-shaft Engine | 125/250/500 | 16.1 | 549 | NA |
> 80 cc--< 225 cc Vertical-shaft Engine | NA | 16.1 | 467 | NA | |
>=225 cc | 125/250/500 | 12.1 | 549 | NA | |
2006 | > 80 cc--< 225 cc | 125/250/500 | 16.1 | 549 | NA |
>= 225 cc | 125/250/500 | 12.1 | 549 | NA | |
2007 | > 80 cc--< 225 cc | 125/250/500 | 10.0 | 549 | NA |
>= 225 cc | 125/250/500 | 12.1 | 549 | NA | |
2008 through 2023 | > 80 cc--< 225 cc | 125/250/500 | 10.0 | 549 | NA |
>= 225 cc | 125/250/500/1000 | 8.0 | 549 | NA |
Exhaust Emission Standards for Spark-Ignition Engines, Except Generator Engines and >= 225 cc Pressure Washer Engines
(grams per kilowatt-hour)
Model Year | Displacement Category | Durability Periods (hours) | Hydrocarbon plus Oxides of Nitrogen(2,6,7) | Carbon Monoxide(7) | Particulate Matter(7) |
2024 and subsequent | < 50 cc | 300 | 0.00 | 536 | 0.00(4) |
2024 and subsequent | 50-80 cc, inclusive | 300 | 0.00 | 536 | 0.00(4) |
2024 and subsequent | > 80 cc--< 225 cc | 500 | 0.00 | 549 | NA |
2024 and subsequent | 225-825 cc, inclusive | 1,000 | 0.00 | 549 | NA |
2024 and subsequent | > 825 cc | 1,000 | 0.00 | 20.6 | NA |
Exhaust Emission Standards for Generator Engines
(grams per kilowatt-hour)
Model Year | Displacement Category | Durability Periods (hours) | Hydrocarbon plus Oxides of Nitrogen(2,8) | Carbon Monoxide(8) | Particulate Matter(8) |
2024 through 2027 | < 50 cc | 500 | 6.0 | 400 | 2.0(4) |
2024 through 2027 | 50-80 cc, inclusive | 500 | 6.0 | 400 | 2.0(4) |
2024 through 2027 | > 80 cc--< 225 cc | 500 | 6.0 | 400 | NA |
2024 through 2027 | 225-825 cc, inclusive | 1,000 | 3.0 | 200 | NA |
2024 through 2027 | > 825 cc | 1,000 | 0.80 | 20.6 | NA |
2028 and subsequent | < 50 cc | 300 | 0.00 | 400 | 0.00(4) |
2028 and subsequent | 50-80 cc, inclusive | 300 | 0.00 | 400 | 0.00(4) |
2028 and subsequent | > 80 cc--< 225 cc | 500 | 0.00 | 400 | NA |
2028 and subsequent | 225-825 cc, inclusive | 1,000 | 0.00 | 200 | NA |
2028 and subsequent | > 825 cc | 1,000 | 0.00 | 20.6 | NA |
Exhaust Emission Standards for >= 225 cc Pressure Washer Engines
(grams per kilowatt-hour)
Model Year | Displacement Category | Durability Periods (hours) | Hydrocarbon plus Oxides of Nitrogen(2,9) | Carbon Monoxide(9) | Particulate Matter(9) |
2024 through 2027 | 225-825 cc, inclusive | 1,000 | 3.0 | 200 | NA |
2024 through 2027 | > 825 cc | 1,000 | 0.80 | 20.6 | NA |
2028 and subsequent | 225-825 cc, inclusive | 1,000 | 0.00 | 200 | NA |
2028 and subsequent | > 825 cc | 1,000 | 0.00 | 20.6 | NA |
(1) "Class I" means small off-road engines greater than 65 cc to less than 225 cc in displacement. | |||||
"Class II" means small off-road engines greater than or equal to 225 cc in displacement. | |||||
"Class III" means small off-road engines less than 20 cc in displacement. | |||||
"Class IV" means small off-road engines 20 cc to less than 50 cc in displacement. | |||||
"Class V" means small off-road engines greater than or equal to 50 cc to 65 cc in displacement. | |||||
(2) The Executive Officer may allow gaseous-fueled (i.e., propane, natural gas) engine families, that satisfy the requirements of the regulations, to certify to either the hydrocarbon plus oxides of nitrogen or hydrocarbon emission standard, as applicable, on the basis of the non-methane hydrocarbon (NMHC) portion of the total hydrocarbon emissions. | |||||
(3) Applicable to all diesel-cycle engines. | |||||
(4) Applicable to all two-stroke engines. | |||||
(5) Engines used exclusively in snowthrowers and ice augers need not certify to or comply with the HC and NOx standards or the crankcase requirements at the option of the manufacturer. | |||||
(6) Engines used exclusively to power products which are used exclusively in wintertime, such as snowthrowers and ice augers, at the option of the engine manufacturer, need not certify to or comply with standards regulating emissions of HC+NOx or NMHC+NOx, as applicable. If the manufacturer exercises the option to certify to standards regulating such emissions, such engines must meet such standards. If the engine is to be used in any equipment or vehicle other than an exclusively wintertime product such as a snowthrower or ice auger, it must be certified to the applicable standard regulating emissions of HC+NOx or NMHC+NOx as applicable. | |||||
(7) Applicable to all small off-road engines, except generator engines engines and >= 225 cc pressure washer engines. | |||||
(8) Applicable only to generator engines. The CO emission standards for marine generator engines in all displacement categories are 4.5 g·kWh-1. | |||||
(9) Applicable only to >= 225 cc pressure washer engines. |
Voluntary standards valid through model year 2023. Engines may be designated "Blue Sky Series" engines by meeting:
Voluntary Emission Standards
(grams per kilowatt-hour)
Model Year | Displacement Category | Hydrocarbon plus Oxides of Nitrogen | Carbon Monoxide | Particulate Matter * |
2005 through 2023 | < 50 cc | 25 | 536 | 2.0 |
50--80 cc, inclusive | 36 | 536 | 2.0 | |
2007 through 2023 | > 80 cc--< 225 cc | 5.0 | 549 | NA |
2008 through 2023 | >=225 cc | 4.0 | 549 | NA |
* Applicable to all two-stroke engines
where
n = the number of small off-road engine families.
FEL = the Family emission limit for an engine family.
Salesj = eligible sales of engine family j.
Powerj = sales-weighted maximum modal power, in horsepower or kilowatt as applicable, of engine family j, or an alternative approved by the Executive Officer.
EDPj = Emissions durability period of engine family j, in hours.
AVG = For a given pollutant (HC+NOx, CO, or Particulate Matter), a manufacturer's corporate average of the exhaust emissions from those California small off-road engines subject to the California corporate average pollutant exhaust emission standard, as established by an Executive Order certifying the California production for the model year. Engines certified to voluntary standards of 2403(b)(2) are not eligible for corporate averaging.
Credits expended = HC+NOx or Particulate Matter credits, as defined in sections 2408 and 2409, that are expended by the manufacturer to adjust the corporate average. This term has no meaning for any pollutants other than HC+NOx and Particulate Matter.
Load Factor = For Test Cycle A and Test Cycle B, the Load Factor = 47% (i.e., 0.47). For Test Cycle C, the Load Factor = 85% (i.e., 0.85). For approved alternate test procedures, the load factor must be calculated according to the Load Factor formula found in paragraph (f)(1) of section 2408.
This Engine Does Not Comply with California Off-Road or On-Highway Emission Requirements. Sale or Installation of this Engine for Any Purpose Other Than as a Replacement Engine in an Off-Road Vehicle or Piece of Off-Road Equipment Whose Original Engine Was Not Certified Is a Violation of California Law Subject to Civil Penalty.
Cal. Code Regs. Tit. 13, § 2403
2. Amendment of subsections (a), (b), (b)(4)(ii), (c), (d), (e) and NOTE filed 10-4-93; operative 11-3-93 (Register 93, No. 41).
3. Change without regulatory effect repealing article heading and amending NOTE filed 12-22-93 pursuant to title 1, section 100, California Code of Regulations (Register 93, No. 52).
4. Amendment of subsection (c) filed 10-18-94; operative 10-18-94 pursuant to Government Code section 11346.2(d) (Register 94, No. 42).
5. Amendment filed 7-24-95; operative 7-24-95 pursuant to Government Code section 11343.4(d) (Register 95, No. 30).
6. Amendment of subsections (b) and (c) filed 8-29-96; operative 8-29-96 pursuant to Government Code section 11343.4 (d) (Register 96, No. 35).
7. Editorial correction of Table and subsection (f) (Register 97, No. 8).
8. Amendment of Table and new subsection (b)(6) filed 2-20-97; operative 2-20-97 pursuant to Government Code section 11343.4(d) (Register 97, No. 8).
9. Amendment of section heading, section and NOTE filed 3-23-99; operative 3-23-99 pursuant to Government Code section 11343.4(d) (Register 99, No. 13).
10. Change without regulatory effect amending subsection (c)(7) filed 7-7-99 pursuant to section 100, title 1, California Code of Regulations (Register 99, No. 28).
11. Amendment of table contained within subsection (b) and amendment of subsection (d) filed 12-28-2000; operative 12-28-2000 pursuant to Government Code section 11343.4(d) (Register 2000, No. 52).
12. Amendment filed 9-20-2004; operative 10-20-2004 (Register 2004, No. 39).
13. Amendment of subsection (b)(2)(B), new subsection (b)(3), subsection renumbering and amendment of subsections (d) and (e)(1) filed 4-5-2010; operative 5-5-2010 (Register 2010, No. 15).
14. Amendment of subsections (b)(2)(B) and (d) filed 12-11-2012; operative 1-10-2013 (Register 2012, No. 50).
15. Amendment filed 9-14-2022; operative 1-1-2023 (Register 2022, No. 37).
Note: Authority cited: Sections 39600, 39601, 43013, 43018, 43101, 43102 and 43104, Health and Safety Code. Reference: Sections 43013, 43017, 43018, 43101, 43102, 43104, 43150- 43154, 43205.5 and 43210- 43212, Health and Safety Code.
2. Amendment of subsections (a), (b), (b)(4)(ii), (c), (d), (e) and Note filed 10-4-93; operative 11-3-93 (Register 93, No. 41).
3. Change without regulatory effect repealing article heading and amending Note filed 12-22-93 pursuant to title 1, section 100, California Code of Regulations (Register 93, No. 52).
4. Amendment of subsection (c) filed 10-18-94; operative 10-18-94 pursuant to Government Code section 11346.2(d) (Register 94, No. 42).
5. Amendment filed 7-24-95; operative 7-24-95 pursuant to Government Code section 11343.4(d) (Register 95, No. 30).
6. Amendment of subsections (b) and (c) filed 8-29-96; operative 8-29-96 pursuant to Government Code section 11343.4(d) (Register 96, No. 35).
7. Editorial correction of Table and subsection (f) (Register 97, No. 8).
8. Amendment of Table and new subsection (b)(6) filed 2-20-97; operative 2-20-97 pursuant to Government Code section 11343.4(d) (Register 97, No. 8).
9. Amendment of section heading, section and Note filed 3-23-99; operative 3-23-99 pursuant to Government Code section 11343.4(d) (Register 99, No. 13).
10. Change without regulatory effect amending subsection (c)(7) filed 7-7-99 pursuant to section 100, title 1, California Code of Regulations (Register 99, No. 28).
11. Amendment of table contained within subsection (b) and amendment of subsection (d) filed 12-28-2000; operative 12-28-2000 pursuant to Government Code section 11343.4(d) (Register 2000, No. 52).
12. Amendment filed 9-20-2004; operative 10-20-2004 (Register 2004, No. 39).
13. Amendment of subsection (b)(2)(B), new subsection (b)(3), subsection renumbering and amendment of subsections (d) and (e)(1) filed 4-5-2010; operative 5-5-2010 (Register 2010, No. 15).
14. Amendment of subsections (b)(2)(B) and (d) filed 12-11-2012; operative 1-10-2013 (Register 2012, No. 50).
15. Amendment filed 9-14-2022; operative 1/1/2023 (Register 2022, No. 37).