Title 42The Public Health and WelfareRelease 119-73

§16104 Reduction of engine idling

Title 42 › Chapter CHAPTER 149— - NATIONAL ENERGY POLICY AND PROGRAMS › Subchapter SUBCHAPTER VII— - VEHICLES AND FUELS › Part Part D— - Miscellaneous › § 16104

Last updated Apr 6, 2026|Official source

Summary

Requires the EPA to study and help cut long idling by big diesel trucks and locomotives. The EPA must start reviews within 90 days after August 8, 2005 and finish them within 180 days. The reviews check whether EPA’s emissions models show pollution from engines idling more than 15 minutes and whether “idle reduction” technologies actually cut emissions and save fuel. The EPA must update models, rules, and guidance if needed, publish reports, and run a program with the Transportation Department (through SmartWay) to promote idle-reduction and fuel-saving technologies. The law names key terms: Administrator = EPA Administrator; advanced truck stop electrification system = stationary systems that give heat, A/C, power, or communications and can prove use; auxiliary power unit = certified on-vehicle system that provides heat, A/C, engine warming, or electricity; heavy-duty vehicle = diesel vehicle over 8,500 pounds GVWR; idle reduction technology = systems that stop long idling by letting engines be turned off; energy conservation technology = anything that improves fuel economy; long-duration idling = engine running over 15 straight minutes while not in gear (not traffic stops). The law also requires studies of places where trucks stop (truck stops, rest areas, border crossings, ports, transfer points, private terminals) with reports due in 180 days. It authorizes funding for deployment: for heavy-duty vehicles $19,500,000 (FY2006), $30,000,000 (FY2007), $45,000,000 (FY2008); for locomotives $10,000,000 (FY2006), $15,000,000 (FY2007), $20,000,000 (FY2008). At least 50% of project costs must come from non-Federal sources unless the EPA reduces that share. Within 60 days after the first grants are awarded, and every year after, the EPA must report to Congress naming grant recipients, describing projects and funding, and listing all other applicants.

Full Legal Text

Title 42, §16104

The Public Health and Welfare — Source: USLM XML via OLRC

(a)In this section:
(1)The term “Administrator” means the Administrator of the Environmental Protection Agency.
(2)The term “advanced truck stop electrification system” means a stationary system that delivers heat, air conditioning, electricity, or communications, and is capable of providing verifiable and auditable evidence of use of those services, to a heavy-duty vehicle and any occupants of the heavy-duty vehicle with or without relying on components mounted onboard the heavy-duty vehicle for delivery of those services.
(3)The term “auxiliary power unit” means an integrated system that—
(A)provides heat, air conditioning, engine warming, or electricity to components on a heavy-duty vehicle; and
(B)is certified by the Administrator under part 89 of title 40, Code of Federal Regulations (or any successor regulation), as meeting applicable emission standards.
(4)The term “heavy-duty vehicle” means a vehicle that—
(A)has a gross vehicle weight rating greater than 8,500 pounds; and
(B)is powered by a diesel engine.
(5)The term “idle reduction technology” means an advanced truck stop electrification system, auxiliary power unit, or other technology that—
(A)is used to reduce long-duration idling; and
(B)allows for the main drive engine or auxiliary refrigeration engine to be shut down.
(6)the 11 So in original. Probably should be capitalized. term “energy conservation technology” means any device, system of devices, or equipment that improves the fuel economy.
(7)(A)The term “long-duration idling” means the operation of a main drive engine or auxiliary refrigeration engine, for a period greater than 15 consecutive minutes, at a time at which the main drive engine is not engaged in gear.
(B)The term “long-duration idling” does not include the operation of a main drive engine or auxiliary refrigeration engine during a routine stoppage associated with traffic movement or congestion.
(b)(1)Not later than 90 days after August 8, 2005, the Administrator shall—
(A)(i)commence a review of the mobile source air emission models of the Environmental Protection Agency used under the Clean Air Act (42 U.S.C. 7401 et seq.) to determine whether the models accurately reflect the emissions resulting from long-duration idling of heavy-duty vehicles and other vehicles and engines; and
(ii)update those models as the Administrator determines to be appropriate; and
(B)(i)commence a review of the emission reductions achieved by the use of idle reduction technology; and
(ii)complete such revisions of the regulations and guidance of the Environmental Protection Agency as the Administrator determines to be appropriate.
(2)Not later than 180 days after August 8, 2005, the Administrator shall—
(A)complete the reviews under subparagraphs (A)(i) and (B)(i) of paragraph (1); and
(B)prepare and make publicly available one or more reports on the results of the reviews.
(3)The reviews under subparagraphs (A)(i) and (B)(i) of paragraph (1) and the reports under paragraph (2)(B) may address the potential fuel savings resulting from use of idle reduction technology.
(4)(A)(i)Not later than 90 days after August 8, 2005, the Administrator, in consultation with the Secretary of Transportation shall, through the Environmental Protection Agency’s SmartWay Transport Partnership, establish a program to support deployment of idle reduction and energy conservation technologies.
(ii)The Administrator shall give priority to the deployment of idle reduction and energy conservation technologies based on the costs and beneficial effects on air quality and ability to lessen the emission of criteria air pollutants.
(B)(i)There are authorized to be appropriated to the Administrator to carry out subparagraph (A) for the purpose of reducing extended idling from heavy-duty vehicles $19,500,000 for fiscal year 2006, $30,000,000 for fiscal year 2007, and $45,000,000 for fiscal year 2008.
(ii)There are authorized to be appropriated to the administrator to carry out subparagraph (A) for the purpose of reducing extended idling from locomotives $10,000,000 for fiscal year 2006, $15,000,000 for fiscal year 2007, and $20,000,000 for fiscal year 2008.
(iii)Subject to clause (iv), the Administrator shall require at least 50 percent of the costs directly and specifically related to any project under this section to be provided from non-Federal sources.
(iv)The Administrator may reduce the non-Federal requirement under clause (iii) if the Administrator determines that the reduction is necessary and appropriate to meet the objectives of this section.
(5)(A)Not later than 90 days after August 8, 2005, the Administrator, in consultation with the Secretary of Transportation, shall commence a study to analyze all locations at which heavy-duty vehicles stop for long-duration idling, including—
(i)truck stops;
(ii)rest areas;
(iii)border crossings;
(iv)ports;
(v)transfer facilities; and
(vi)private terminals.
(B)Not later than 180 days after August 8, 2005, the Administrator shall—
(i)complete the study under subparagraph (A); and
(ii)prepare and make publicly available one or more reports of the results of the study.
(c)
(d)Not later than 60 days after the date on which funds are initially awarded under this section, and on an annual basis thereafter, the Administrator shall submit to Congress a report containing—
(1)an identification of the grant recipients, a description of the projects to be funded and the amount of funding provided; and
(2)an identification of all other applicants that submitted applications under the program.

Legislative History

Notes & Related Subsidiaries

Editorial Notes

References in Text

The Clean Air Act, referred to in subsec. (b)(1)(A)(i), is act July 14, 1955, ch. 360, 69 Stat. 322, which is classified generally to chapter 85 (§ 7401 et seq.) of this title. For complete classification of this Act to the Code, see

Short Title

note set out under section 7401 of this title and Tables. Codification Section is comprised of section 756 of Pub. L. 109–58. Subsec. (c) of section 756 of Pub. L. 109–58 amended section 127 of Title 23, Highways.

Reference

Citations & Metadata

Citation

42 U.S.C. § 16104

Title 42The Public Health and Welfare

Last Updated

Apr 6, 2026

Release point: 119-73