CALIFORNIA Valves utilise a swing-check valve arrangement with an acceleration-sensitive triggering mechanism. The trip mechanism consists of a steel ball that rests on tapered cup-shaped support. The horizontal motions of an earthquake cause the ball to move from the centre of the support, which allows the ball’s mass to act upon the movable pipe of the trip mechanism to actuate the valve and initiate closure.
CALIFORNIA Valves do not use any source of internal or external electrical power. They remain closed until manually reset. These valves are mounted in the gas line upstream or downstream of the gas-line pressure regulator and gas meter outside the structure.
CALIFORNIA Valves do not replace manual shutoff valves installed in the gas service line. Springs assist in closing, and gas pressure helps in holding the disc in the closed position. The trip mechanism is factory set and sealed. A sight glass combined with an open/closed indicator that has green (i.e., open) and red (i.e., closed) bars enables the valve’s position to be easily and quickly determined.