Abstract: The present invention discloses an automatic gas shut-off valve which has associated therewith a seismic sensor unit. The seismic sensor unit can be either an electric unit or mechanical unit or both. In operation, the seismic sensor is triggered by a seismic event to the dump/default or shut-off position whereupon the seismic sensor then causes the automatic gas shut-off valve to close and remain closed, thereby stopping the potential continued release of gas. The electric seismic unit with user reset can be located within the protected confines of a structure in a manner similar to today's electric circuit breaker box. This systems allows the consumer to restore gas to his own structure after determining that the gas lines and appliances are safe and undamaged, just as can be done with a tripped electric circuit breaker, without having to call in the utility company.