Laws and rules pertaining to boilers, water heaters, and unfired pressure vessels can be found in the following:

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) are considering changes to the state boiler rules and fees.

The changes would affect rules under chapter 296-104 WAC, Board of Boiler Rules – Substantive.

L&I filed a CR-101 Preproposal Statement of Inquiry on October 21.

About the rulemaking

The Board reviews the rules on a regular basis to ensure consistency with national boiler and unfired pressure vessel safety standards and industry practice. This rulemaking is needed to make updates, clarification, housekeeping, and other changes.

The changes under consideration include:

  • Adding and amending definitions to clarify meaning of terms;
  • Clarifying inspection requirements for low pressure boilers;
  • Extending the inspection interval of boilers for owner/user organizations;
  • Establishing new requirements for operation and maintenance of boilers; and
  • Increasing fees by the fiscal growth factor for fiscal year 2027.

Rulemaking documents

Notice of intent (10/21/2025)

Here’s what happens next:

  • January 6, 2026: Proposed rules (CR-102) are expected to be filed.
  • February 25, 2026: A Public hearing on the proposed rules is tentatively scheduled.
  • April 21, 2026: Final rules (CR-103) are expected to be adopted.
  • July 1, 2026: New rules would take effect.

2024 rulemaking

The Board of Boiler Rules have adopted an increase in program fees and clarified the definition for pool heaters.

The agency adopted a 6.41% fee increase to cover L&I Boiler Program operating expenses.

The adopted rule amendments take effect July 1, 2025.

Rulemaking documents

Notice of intent (10/22/2024)

Proposed rule language (01/02/2025)

Final adoption (4/22/2025)

All Boiler Program Rulemaking