Chapters 173-400 and 173-401 WAC, General Regulations for Air Pollution Sources

We propose to update two rules:

This rulemaking may also:

  • Clarify language.
  • Improve regulatory requirements for air quality.

Rulemaking timeline


Announcement phase (CR-101)

Filing date:
Jan. 18, 2024

Announcement documents

Rule development phase

Jan. 18, 2024 – Fall 2024

Public input & involvement

Public comment period (informal)
April 18, 2024, 8 a.m. – May 31, 2024, 11:59 p.m.

Comment on the draft rule and the draft source test manual
Read comments.

Ecology's meetings with stakeholders

Date Documents Location
April 18, 2024
10 a.m. – 11:30 a.m.
Draft rule language (173-400)
Draft rule language (173-401)
Draft source test manual

webinar 1

May 15, 2024
10 a.m. – 11:30 a.m.
Draft source test manual
webinar 1

1 Webinar information:
   Register for each webinar to get your meeting ID and passcode.
   To hear the webinar better or to call in only, use your phone (instead of the computer) to call 253‑215‑8782.

Additional languages

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