Emergency Pressure and Vacuum Relief Vent

Emergency Pressure and Vacuum Relief Vent

Series No. 52600

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)(2)(v)]
  • Sizes: 16” (DN 400) through 24” (DN 600)
  • Flange Connections: Mates with applicable ANSI, API flange or DIN 16 PN connections
  • Materials: Aluminum, Steel and Stainless Steel
  • Testing & Certifications: Conforms with the latest ATEX Directive
  • Standard Setting Range*: Pressure: 0.75 – 6 oz/in2 | 3.23 – 25.86 mbar
  • Standard Setting Range*: Vacuum: 0.5 – 0.75 oz/in2 | 2.15 – 3.23 mbar

*Settings vary by size

  • Flange Connections: Other drilling patterns available upon request
  • Diaphragm Materials: FEP, Viton®, Buna N, EPDM, and Neoprene; other materials available upon request
  • *Settings: Non-standard setting available
  • Special Coatings: PROSHIELD™, FEP and Kynar®
  • Instrumentation: Mechanical or electronic lift indicator
  • Material certifications for flange and seat
  • PURE-TECH™ Design – Special cleaning and packaging for the storage of ultrapure liquids


Viton® is a Registered Trademark of E. I. DuPont de Nemours & Co., Inc.
Kynar® is a Registered Trademark of Arkema, Inc.