Earthquakes are a fact of life for Californians, but that doesn’t make them any less dangerous. Most fatalities from earthquakes are not due to shaking but from fires that occur when gas lines break and leak.
And considering that about 25 earthquakes with a magnitude between 4.0 and 5.0 occur in California and Nevada every year, with multiple smaller earthquakes happening every day, you never know when one is going to ruin your day. That’s why all homes in California must have a way to automatically shut off gas lines in the event of a pipe break or natural disaster.
Thankfully, turning the gas back after an earthquake is a quick and easy process.
What is a seismic valve?
Seismic valves, also known as earthquake valves, are a critical safety feature in your plumbing system. When a seismic valve senses strong enough vibrations, it cuts off the flow of gas to your home. These valves are often designed with a ball bearing set on a spring-loaded trap door the blocks the gas line.
The magnitude needed to trigger most seismic valves is 5.4 or larger. Your shutoff valve should not be triggered by normal vibrations like those caused by train tracks, traffic, or someone bumping into it. If you find that your gas shuts off by everyday vibrations, your gas line may need to be braced against the building.
This type of valve is most common in states like California that have a higher risk of earthquakes. In Marin County and California as a whole, local building codes require residents to have a gas shutoff valve installed.
How do I reset my seismic valve?
Your seismic valve is located on the outside of your home, downstream of your gas utility meter.
When you inspect your shutoff valve, you will see a color on top that indicates whether gas is still flowing or not.
- Red indicates that the gas is shut off.
- Green means that your gas line is open.
To reset, all you need is a screwdriver. Insert the screwdriver into the reset slot and rotate clockwise. You should be able to see the color switch from red to green to indicate that the valve is now open.
Get Your Plumbing System Inspected After an Earthquake
Even if you reset your gas shutoff valve yourself, it’s still a good idea to get your plumbing inspected. Natural disasters can cause any number of problems to your plumbing system, and a professional will be able to inspect your natural gas appliances to ensure that you are not at risk of a dangerous gas leak.