Seattle, WA Earthquake Safety: Seismic Gas Shutoff (2026)
Key Facts
- Required Since
- Building permits after January 26, 1995
- Standard
- ANSI Z21.93-13/CSA 6.30-13
- Activation Level
- 5.2 magnitude earthquake or greater
- Installation
- Licensed plumber or gas fitter required
- Cost Range
- Approximately $300-$500 installed
Summary
Washington state requires seismic gas shutoff valves for buildings where a building permit was first issued on or after January 26, 1995. Valves must be installed downstream of the gas utility meter and comply with ANSI Z21.93 standards. The valve automatically closes the gas supply when it detects significant seismic activity (5.2 magnitude or greater).
2024 International Fuel Gas Code (IFGC) 409.3.4 — Seismic Gas Shutoff Valves: An approved seismic gas shutoff valve shall be installed downstream of the gas utility meter on each fuel gas piping where the gas serves the following buildings or structures: Group A, B, E, F-1, F2, H1-5, I1-4, M, R1-2, S, And U, (excluding Group R3) Section 301-312 classified in the IBC Chapter 3. When: A building or structure containing fuel gas piping for which a building permit was first issued on or after January 26th, 1995. An alteration or addition is to the Fuel Gas Piping system and involves the alteration or replacement of the gas meter. The Seismic Gas Shutoff Valve shall be installed in accordance with ANSI Z21.93-13/CSA 6.30-13 and the manufacturer's instructions. The Seismic Gas Shutoff Valve shall be plainly marked as such and their locations posted as required by the Authority Having Jurisdiction. [NFPA 54:7.8.2.3] Seismic Gas Shutoff Valve refers to a system designed to automatically close a gas valve in response to significant seismic activity, triggering upon detecting a 5.2 or greater earthquake.
Full Breakdown
Seismic gas shutoff valves are required in Washington state for buildings with building permits first issued on or after January 26, 1995. 30-13 and the manufacturer's installation instructions. The Washington State Building Code Council has adopted these requirements as part of the state's fuel gas code. 2 magnitude or greater earthquakes) and automatically closes the gas valve to prevent gas leaks that could cause fires or explosions after an earthquake. Installation must be performed by a licensed plumber or gas fitter. After activation, the valve must be manually reset by a qualified person who has confirmed there are no gas leaks.
While not retroactively required for older buildings, Seattle seismic retrofit professionals strongly recommend installing shutoff valves on all buildings, especially those in liquefaction zones or near known fault lines. The valves cost approximately $300-$500 installed and provide significant protection against post-earthquake fire hazards.
Violations & Fines
New construction without required seismic gas shutoff valves will fail the gas piping inspection and receive a correction notice from SDCI. Operating gas piping without required shutoff valves in post-1995 buildings is a code violation. Installation by unlicensed individuals is a violation of state licensing requirements.
Frequently Asked Questions
Does my Seattle home need a seismic gas shutoff valve?
What happens when a seismic gas shutoff valve activates?
Sources & Official References
Other rules in Seattle
Compare Seattle to another location·View the Washington earthquake safety overview
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