Flame Cap Kilns, Chapters 173-425, 173-430, 173-400 WAC
Proposed rulemaking — online public hearing
Jan. 6, 2026, 10 a.m. PT, online webinar
We are holding a public hearing about the rulemaking to update three rules:
- Chapter 173-425 WAC, Outdoor burning
- Chapter 173-430 WAC, Agricultural burning
- Chapter 173-400-050 WAC, Emission standards for combustion and incineration units
With this rulemaking, we propose to:
- Add the definition of flame cap kilns.
- Include flame cap kilns as an allowed burning device. A flame cap kiln is an outdoor container used to burn natural vegetation from forestry or agricultural activities.
- Make sure flame cap kilns are only used for burning that is already legal in Washington.
- Update the definition of silvicultural burning to include combustion.
- Permit the use of air curtain incinerators. An air curtain incinerator is a portable container used to burn woody debris (slash) from forestry operations.
- Make the process for getting a permit to use an air curtain incinerator easier for both applicants and staff.
Background
We write rules to implement and enforce state and federal environmental laws and rules. Ecology follows a three-phase process for rulemaking:
- Announcement and development
- Proposal
- Adoption
For each phase of the process, we update the rulemaking web page and notify interested parties. We also file notice in the Washington State Register. To learn more about Ecology’s rulemaking process, read the Frequently Asked Questions.
Time
Questions
To request ADA accommodation, contact Ecology's ADA Coordinator by email at ecyadacoordinator@ecy.wa.gov, or call 360-407-6831, 711 (relay service), or 877-833-6341 (TTY). More about our accessibility services.
Comment period
Flame Cap Kilns and Air Curtain Incinerators, Chapters 173-425, 173-430, and 173-400 WAC — Proposed rulemaking – public comment period
Closes: Jan. 20, 2026, 11:59 p.m.
See details