EPA seeks to reverse Endangerment Finding, halt vehicle GHG emissions rules
The Environmental Protection Agency (EPA) has proposed a rule to rescind the 2009 Endangerment Finding and repeal all greenhouse gas (GHG) emissions standards for:
- Light-duty vehicles,
- Medium-duty vehicles,
- Heavy-duty vehicles, and
- Heavy-duty vehicle engines.
What’s the Endangerment Finding?
In 2009, EPA issued two findings: the Endangerment Finding and the Cause or Contribute Finding, generally referred to as the 2009 Endangerment Finding. The agency uses the findings as the foundation for statutory authority to regulate GHG emissions under Section 202(a) of the Clean Air Act. In other words, the 2009 Endangerment Finding is the legal basis the agency uses to regulate GHG emissions from new motor vehicles and vehicle engines.
Under the 2009 Endangerment Finding, EPA regulates new motor vehicles and vehicle engines through:
- Emissions standards and related requirements, and
- Engine and vehicle certification requirements.
How does this impact vehicle regulations?
If EPA rescinds the 2009 Endangerment Finding, it will no longer have the statutory authority to regulate emissions from new motor vehicles and vehicle engines. As a result, EPA would remove all GHG emissions regulations that apply to new motor vehicle and vehicle engine manufacturers in 40 CFR:
- Parts 85, 86, and 600 (light- and medium-duty vehicles),
- Part 1036 (heavy-duty vehicle engines), and
- Part 1037 (heavy-duty vehicles).
Affected compliance requirements include:
- Emissions standards;
- Test procedures;
- Averaging, banking, and trading requirements;
- Reporting requirements; and
- Fleet-average emission requirements.
Manufacturers would no longer have to measure, control, or report GHG emissions for any vehicle or vehicle engine, including previously manufactured model years.
What won’t change?
The proposed rule doesn’t affect:
- Criteria pollutant and air toxic (or hazardous air pollutant) measurement and standards,
- Corporate Average Fuel Economy (or CAFE) testing, and
- Associated fuel economy labeling requirements.
What’s next?
EPA will accept public comments on the rule through September 15, 2025. Additionally, the agency will hold a virtual public hearing on August 19 and 20, 2025. EPA will use the feedback to inform how it will proceed in the rulemaking process.
Key to remember: EPA has proposed a rule to rescind the 2009 Endangerment Finding and repeal GHG emissions standards for new motor vehicles and vehicle engines.