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40 CFR Part 1054, Appendix A — Summary of Previous Emission Standards

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov

The following standards, which EPA originally adopted under 40 CFR part 90, apply to nonroad spark-ignition engines produced before the model years specified in § 1054.1:

(a) Handheld engines. (1) Phase 1 standards apply for handheld engines as summarized in the following table starting with model year 1997:

Engine displacement classHCNOXCO
Class III2955.36805
Class IV2415.36805
Class V1615.36603

a Phase 1 standards are based on testing with new engines only.

(2) Phase 2 standards apply for handheld engines as summarized in the following table starting with model year 2002 for Class III and Class IV, and starting in model year 2004 for Class V:

Engine displacement classHC + NOXCO
Class IIIa 50805
Class IVb 50805
Class Vc 72603

a Class III engines had alternate HC+NOX standards of 238, 175, and 113 for model years 2002, 2003, and 2004, respectively.

b Class IV engines had alternate HC+NOX standards of 196, 148, and 99 for model years 2002, 2003, and 2004, respectively.

c Class V engines had alternate HC+NOX standards of 143, 119, and 96 for model years 2004, 2005, and 2006, respectively.

(b) Nonhandheld engines. (1) Phase 1 standards apply for nonhandheld engines as summarized in the following table starting with model year 1997:

Engine displacement classHC + NOXCO
Class I16.1519
Class II13.4519

a Phase 1 standards are based on testing with new engines only.

(2) Phase 2 standards apply for nonhandheld engines as summarized in the following table starting with model year 2001 (except as noted for Class I engines):

Engine displacement classHC + NOXNMHC + NOXCO
Class I-A50| 610
Class I-B4037610
Class I a16.114.8610
Class II b12.111.3610

a The Phase 2 standards for Class I engines apply for new engines produced starting August 1, 2007, and for any engines belonging to an engine model whose original production date was on or after August 1, 2003.

b Class II engines had alternate HC + NOX standards of 18.0, 16.6, 15.0, 13.6 and alternate NMHC + NOX standards of 16.7, 15.3, 14.0, 12.7 for model years 2001 through 2004, respectively.

(3) Note that engines subject to Phase 1 standards were not subject to useful life, deterioration factor, production-line testing, or in-use testing provisions. In addition, engines subject to Phase 1 standards and engines subject to Phase 2 standards were both not subject to the following provisions:

(i) Evaporative emission standards as specified in §§ 1054.110 and 1054.112.

(ii) Altitude adjustments as specified in § 1054.115(c).

(iii) Warranty assurance provisions as specified in § 1054.120(f).

(iv) Emission-related installation instructions as specified in § 1054.130.

(v) Bonding requirements as specified in § 1054.690.

[86 FR 34526, June 29, 2021. Redesignated and amended at 88 FR 4668, Jan. 24, 2023]