Right after the shaking
Illustrative example. Not a real job or customer.
A moderate earthquake rattles a 1950s single-story home in Fullerton late in the evening. Dishes fall, but the power stays on. The family's plan says: smell, sound or visible damage means close the meter and leave; none of those means leave the gas on.
- Everyone gathers in the front yard as practiced and checks on each other.
- One adult goes back to the doorway and sniffs without going in or touching switches: no gas smell.
- Walking around the outside, they find the meter intact and hear no hissing.
- In the garage, the water heater has shifted slightly but is held by its seismic straps. There is no smell near it.
With no smell, no sound and no broken pipe, they leave the gas on and stay alert for any odor through the night.
The choices they weighed
- IfClose the meter just in caseThenRejected: no sign of a leak, and a relight could take a long time after a widespread quake.
- IfSmell or hiss later in the nightThenPlanned: leave, close the meter if safe, call 911 or SoCalGas from outside.
- IfWater heater shifted but strappedThenPlanned: have it and its connector checked soon.
The follow-up visit
A few days later the family has a licensed contractor look at the water heater and the gas connections. The straps held, but the flexible connector to the water heater is old and now pulled at an angle. The vent pipe at the top has slipped partly out of its joint.
The contractor replaces the connector with a new one sized to allow some movement, resets and secures the vent, checks every joint with leak solution, and confirms the water heater flame and draft. They also note that the range connector is old and recommend replacing it before the next quake.
What made this go smoothly
Questions they asked the contractor
- Should we add a seismic gas shutoff valve, and does the city require one?
- Are any of our other connectors due for replacement?
- Is the water heater strapping still correct after the shift?
- Does the vent need any further repair?
Common questions
Is this a real event?
No. It is an invented example to show how the decision is made.
Would a seismic valve have shut the gas off?
It might have tripped, depending on the shaking. Then the family would have needed to reset it and relight appliances.
Why check the vent?
A loose water heater vent can let exhaust into the garage or house. That is a carbon monoxide risk, not a gas leak.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.