Public Hearing and Public Comments: Revision of Tier 4 Criteria Pollutant Standards, Part 1: Amendments to Phase-In Schedule for Light-Duty and Medium-Duty Vehicles

How to Comment

Comments Due: July 6, 2026

Comments must be submitted by 11:59 pm ET on Monday July 6, 2026.

All comments should reference Docket ID No. [EPA–HQ–OAR–2025–3297; FRL–13030–02–OAR] and may be submitted through one of the following methods:

  • Federal eRulemaking Portal
    Follow the online instructions for submitting comments.
  • Mail: 
    U.S. Environmental Protection Agency, EPA Docket Center, OAR Docket, Mail Code 28221T, 1200 Pennsylvania Avenue NW, Washington, DC 20460.
  • Hand Delivery / Courier (if applicable): 
    EPA Docket Center, WJC West Building, Room 3334, 1301 Constitution Avenue, NW, Washington, DC 20004. The Docket Center’s hours of operations are 8:30 a.m. to 4:30 p.m., Monday – Friday (except Federal Holidays).

EPA encourages commenters to submit information electronically to ensure timely receipt and public availability.

Summary

To view documents supporting this proposed rulemaking as well as comments submitted, please visit regulations.gov and access the rule under Docket ID No. EPA–HQ–OAR–2025–3297 or see the Proposed Rule page.

Public Comment Opportunity

EPA invites public comment on the proposed rule, Revision of Tier 4 Criteria Pollutant Standards, Part 1: Amendments to Phase-In Schedule for Light-Duty and Medium-Duty Vehicles which was published in the Federal Register on May 18, 2026 under docket ID number [EPA–HQ–OAR–2025–3297; FRL–13030–02–OAR].

Public Hearing

EPA will hold a public hearing on this proposed rule. Public Hearing Details:

  • Wednesday, June 3 (9:00 am - 9:00 pm EDT) and Thursday, June 4 (10:00 am - 12:00 pm EDT).
  • Email to request the registration form or ask questions about the hearing.
  • Pre-registration ends on May 27th (recommended for those requesting special accommodations), but the registration form will be open through June 2nd.
  • The public hearing will be conducted using Zoom Webinar. Information on how to join the hearing is below. Please note that each day of the hearing has a unique webinar link and ID: 
    • Wednesday, June 3rd 
      Please click the Zoom link to join the webinar: 
      Or One tap mobile:
      +16692545252, 1609245777# US (San Jose) 
      +16468287666, 1609245777# US (New York) 
      Or Telephone: 
      Dial (for higher quality, dial a number based on your current location): 
      +1 669 254 5252 US (San Jose) 
      +1 646 828 7666 US (New York) 
      +1 669 216 1590 US (San Jose) 
      +1 551 285 1373 US (New Jersey) 
      Webinar ID: 160 924 5777 
       
    • Thursday, June 4th
      Please click the Zoom link to join the webinar: 
      Or One tap mobile: 
      +16692545252, 1658069783# US (San Jose) 
      +16468287666, 1658069783# US (New York) 
      Or Telephone: 
      Dial (for higher quality, dial a number based on your current location): 
      +1 669 254 5252 US (San Jose) 
      +1 646 828 7666 US (New York) 
      +1 669 216 1590 US (San Jose) 
      +1 551 285 1373 US (New Jersey) 
      Webinar ID: 165 806 9783 
       
    • International numbers available at Zoom International Dial-in Numbers page.

Availability of Comments

All comments received will be included in the public docket without change and will be made available for public inspection at Federal eRulemaking Portal, including any personally identifiable information provided. Do not submit confidential business information or other sensitive materials unless clearly marked and submitted in accordance with applicable EPA procedures.

Regulations for Emissions from Vehicles and Engines

Contact Us About Regulations for Emissions from Vehicles and Engines
Contact Us About Regulations for Emissions from Vehicles and Engines to ask a question, provide feedback, or report a problem.
Last updated on June 2, 2026