---
kind: "section"
citation: "42 U.S.C. § 7585"
title: "42"
title_heading: "The Public Health and Welfare"
number: "7585"
heading: "Standards for heavy-duty clean-fuel vehicles (GVWR above 8,500 up to 26,000 lbs.)"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/42/7585"
units:
  - "Chapter 85 — Air Pollution Prevention and Control"
  - "Subchapter II — Emission Standards for Moving Sources"
  - "Part C — Clean Fuel Vehicles"
---

# §7585. Standards for heavy-duty clean-fuel vehicles (GVWR above 8,500 up to 26,000 lbs.)

- (a) **Model years after 1997; combined NOx and NMHC standard—** For classes or categories of heavy-duty vehicles or engines manufactured for the model year 1998 or thereafter and having a GVWR greater than 8,500 lbs. and up to 26,000 lbs. GVWR, the standards under this part for [clean-fuel vehicles](/usc/42/7581.md?p=7) shall require that combined emissions of oxides of nitrogen (NO<sub>x</sub>) and nonmethane hydrocarbons (NMHC) shall not exceed 3.15 grams per brake horsepower hour (equivalent to 50 percent of the combined [emission standards](/usc/42/7602.md?p=k) applicable under [section 7521 of this title](/usc/42/7521.md) for such [air pollutants](/usc/42/7602.md?p=g) in the case of a conventional model year 1994 heavy-duty diesel-fueled vehicle or engine). No standard shall be promulgated as provided in this section for any heavy-duty vehicle of more than 26,000 lbs. GVWR.
- (b) **Revised standards that are less stringent—**
  - (1) The [Administrator](/usc/42/7602.md?p=a) may promulgate a revised less stringent standard for the vehicles or engines referred to in [subsection (a)](#a) if the [Administrator](/usc/42/7602.md?p=a) determines that the 50 percent reduction required under [subsection (a)](#a) is not technologically feasible for clean diesel-fueled vehicles and engines, taking into account durability, costs, lead time, safety, and other relevant factors. To provide adequate lead time the [Administrator](/usc/42/7602.md?p=a) shall make a determination with regard to the technological feasibility of such 50 percent reduction before December 31, 1993.
  - (2) Any [person](/usc/42/7602.md?p=e) may at any time petition the [Administrator](/usc/42/7602.md?p=a) to make a determination under [paragraph (1)](#b-1). The [Administrator](/usc/42/7602.md?p=a) shall act on such a petition within 6 months after the petition is filed.
  - (3) Any revised less stringent standards promulgated as provided in this subsection shall require at least a 30 percent reduction in lieu of the 50 percent reduction referred to in [paragraph (1)](#b-1).

## Source credit

(July 14, 1955, ch. 360, title II, § 245, as added Pub. L. 101–549, title II, § 229(a), Nov. 15, 1990, 104 Stat. 2519.)