Chapter 173-423 WAC

On December 27, 2018, Ecology adopted amendments to Chapter 173-423 WAC, Low Emission Vehicles to match California's vehicle emission standards for greenhouse gases effective on December 12, 2018. These changes:

  • Clarify that vehicle makers would need to meet existing standards agreed to by California, the federal government, and automakers in 2012. This would apply to cars and light-duty trucks sold in Washington for model years 2021 through 2025.
  • Update requirements and test procedures for meeting California's vehicle emission standards.
  • Update requirements for on-board diagnostic systems from California's 2015 rulemaking.

Rule proposal phase (CR-102)

Filing date:
Nov. 7, 2018

Rule proposal documents:

Comment period and public hearing

Comments were due by December 18, 2018.  We accepted comments the following ways:

  • Submit online.  View comments.
  • Attend a public hearing (in person and webinar):

           December 11, 2018 at 2 p.m.
           Department of Ecology
           300 Desmond Drive SE
           Lacey, WA  98503

  • Mail to:  Elena Guilfoil
                  Department of Ecology
                  P.O. Box 47600
                  Olympia, WA 98504-7600

Rule adoption phase (CR-103)

Adoption date:
Dec. 27, 2018

Rule effective date:
Jan. 27, 2019

Rule adoption documents:

Rulemaking timeline

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