Pressure/Vacuum Relief Valves are protection devices typically mounted on a nozzle opening on the top of a fixed roof atmospheric storage tank. Their primary purpose is to protect a tank against rupture or implosion by allowing the tank to breathe, or vent, when pressure changes in the tank due to normal operations.
Emergency Relief Valves protect tanks against excessive pressure caused by external fire exposure or flashes within the tank. Emergency relief valves provide higher flow capacity than standard pressure/vacuum relief valves.
Why Pressure/ Vacuum Relief Valves Are Required:
• Saves money by saving product
• Minimizes evaporation emissions
• Protects tank from over or under pressure when sized properly
• Protection against fire hazard when conforming to API standards
• Reduces atmospheric corrosion of tank
• Generally required by OSHA, EPA, etc.