seismic-logoCALIFORNIA (formerly known as Koso) Seismic Gas Shutoff Valves are installed throughout the U.S. and in many countries at risk from earthquakes. They performed well during the 1994 Northridge earthquake. CALIFORNIA Valves have a simple operation principle, remain closed when tilted or bumped, and must be manually reset, which enables safety inspections for leaks and other hazards to be done before gas service is restored. CALIFORNIA Valves have excellent flow characteristics, and may be selected based on the size of a properly sized houseline.CALIFORNIA Valves installed upstream of multiple houselines should be selected based on the sum of the areas of each houseline

Koso valves are earthquake-sensitive gas shutoff valves.  They are designed to closed in the event of a major earthquake to stop the gas flow into a building or house where the gas piping may have been damaged by the earthquake. This reduces the risk of explosion or fire resulting from any damaged to gas piping after a major earthquake.

Koso  valves do not require power source to operate. It can be manually reset after a major earthquake activated the valve but this should be done by a trained LPG technician to ensure it is safe to permit gas to flow into the piping.