The primary purpose of a safety valve is the protection of life, property, and the environment. A safety valve is designed to open and relieve excess pressure from vessels or equipment and to reclose and prevent the further release of fluid after normal conditions have been restored.

A safety valve is a valve that acts as a fail-safe. An example of a safety valve is a pressure relief valve, which automatically releases a substance from a boiler, pressure vessel, or other systems when the pressure or temperature exceeds preset limits.