Pressure-relieving devices protect a vessel or piece of equipment from overpressure but not from failure due to high temperatures when exposed to fire or corrosion. The safety of such failures must be considered separately.
A Pressure Relief Devices that is activated by inlet static pressure and is designed to reclose and prevent further fluid flow after normal conditions have been restored.
The pressure relief valve is a catch-all term for relief valves, safety valves, safety relief valves, and pilot-operated pressure relief valves. A brief description of these valves is provided at the end of this article.