Assuming you're talking about the fuel shut-off mechanism that triggers when your tank is full - the pump nozzle is fitted with a sensor that detects when fuel is 'backing up' rather than flowing properly. The device shuts off the valve delivering the fuel from the nozzle - to prevent it spilling over the car and forecourt.
Install in gas line to shut off gas to building after gas meter, or to isolate an appliance off a gas line.
Ukraine shut off natural gas that goes through Ukraine to European countries, Russia shut off a gas for a while that goes to Ukraine.
An Earthquake Shut-Off Valve is a device designed to automatically shut off the flow of natural gas to a building in the event of an earthquake to prevent gas leaks and potential fires.
Chrysler does not use shut-off switches.
It is probably for when there's a gas leak. The room could go up in flames if there's gas everywhere and it is ignited. The emergency shut off will shut off the gas in case the knobs or a pipe is broken
no
On any water heater, the shut off is on the incoming cold pipe.
One shut off the gas /electric other emergency switch FIRST
If you want to shut it down completely, turn off the cold water stop going into the hot water tank. If it is an electrical tank shut the breaker off to the HWT. If it is a gas HWT, shut off the gas valve as well.
there is a petcock on the tank
No
call your natural gas co. and ask. Natural gas is not something that the novice should be doing. And there are regulations with the kind of system you have in your community. SAFETY IS A GOOD THING.