Laws and rules pertaining to boilers, water heaters, and unfired pressure vessels can be found in the following:
- Washington Administrative Code (WAC) Chapter 296-104.
- Revised Code of Washington (RCW) Chapter 70.79.
The laws and rules are maintained and updated by the State Office of the Code Reviser.
Download our Boilers and Unfired Pressure Vessel Laws Book (updated July 2025).
Rule development
2025 rulemaking
The Board of Boiler Rules (Board) and the Washington State Department of Labor & Industries (L&I) adopted changes to the state boiler rules. The adopted amendments affect the definitions, program fees, and inspection, operation, and maintenance requirements of boilers and pressure vessels.
The changes affect rules under chapter 296-104 WAC, Board of Boiler Rules – Substantive.
L&I filed a CR-103 Proposal on September 1. The new rules take effect October 2, 2026.
Rulemaking documents
Notice of intent (10/21/2025)
Proposed Rule Language (6/2/2026)
- CR-102 Proposed Rulemaking.
- CR-102 Proposed Rule Language.
- Preliminary Cost Benefit Analysis.
- Public Hearing Information Packet.
Final Adoption (9/1/2026)
- CR-103 Adoption.
- CR-103 Adoption Language.
- Concise Explanatory Statement (CES).
- Final Cost Benefit Analysis.