Exploratory rulemaking for Chapter 173-460 WAC

This rulemaking is on hold.

We’ve started exploratory rulemaking to update Chapter 173-460 WAC, Controls for New Sources of Toxic Air Pollutants.  This rule applies to businesses that emit toxic air pollutants to:

  • Provide specific criteria and conditions for permitting new or modified sources.
  • Build on the standard permitting framework for new sources.
  • Establish emission thresholds for about 400 toxic air pollutants.

Exploratory rulemaking

Exploratory rulemaking is a different approach to updating a rule.  Instead of updating the rule all at once, we're making changes through multiple rulemaking actions:

  1. Update the list of toxic air pollutants based on recent health information.
  2. Look at other updates to the rule:
    • Consider other possible changes based on stakeholders' feedback.
    • Prioritize the changes.
  3. Start other potential rulemaking(s).

Public input


Discussion Topics


Aug. 8, 2018
1 p.m. – 3 p.m.
Your ideas about what could be changed.
  • How protective of our health is the current structure?
  • What updates and efficiencies can we add?
  • How can we streamline or standardize implementation?
  • Where can we add flexibility?
Ecology, Lacey (map to location)
webinar *
March 29, 2019
time to be determined

on hold
Bring your ideas about what could be changed.
on hold through 2020
Submit your comments online.
Ecology, Bellevue (map to location)
Northwest Regional Office

* Register to receive your access code and password.
   To hear the webinar better, use your phone (instead of the computer) to call 1-240-454-0887.

Public comment period

Tell us what you think could be updated in this rule.  Submit your comments online and read others' comments.

Rulemaking timeline

Additional languages