Emergency Pressure and Vacuum Relief Vents provide emergency relief when installed on the manhole opening of a storage tank. In emergency situations (external fire involvement of the tank), normal venting devices may be too small to prevent over-pressurization of the tank. The device provides the necessary pressure relief capacity to maintain the tank in a safe operating range. Spring-loaded vacuum pallet assembly allows flow of make-up air into tank’s vapor space to relieve negative pressure.

• Certified test report verifying specified settings and leakage performance
• “Air-cushion” pallet design for low leakage performance of no more than 1 SCFH at 90% of the set pressure
• Peripheral pallet assembly guides and center pallet stem guide ensure proper alignment of pressure pallet assembly on the seat and smooth lifting and reseating action
• Serialized unit and associated weights for easy identification and traceability
• Flow at fully open pressure marked on unit [OSHA 1910.106(b)(3)(v)] Datasheet