The finest gas safety valve is provided by Combustion and control systems that use solenoid valves. These valves come in two varieties: slow opening and rapid closing and fast opening and fast shutting.
The F type valve is a single-stage, fast-opening solenoid valve that is typically closed. When it is charged, it opens. Additionally, the S type valve is a single-stage, slow-opening solenoid valve that is often closed. When it is charged, it opens.