Middlesex Gases


Whisper Valve - Take the Pop Out of Cryogenic Safeties

Users of Liquid Nitrogen, or any cryogenic gases are all too often disturbed by the violent and sudden shock of the noise produced when a cryogenic vessel safety relief valve “pops-off”. This noise has the same decibel rating as a Cadillac horn. Seeing as the lab personnel are commonly in very close proximity to these vessels, this sudden noise can be a safety hazard as well as a nuisance.

Series 8636 Whisper Valve

The Whisper Valve is a silenced safety device for use with cryogenic containers.

The valve solves the problem of the loud noise, over 100dB, associated with the activation of the relief valve in cryogenic containers containing nitrogen, argon or carbon dioxide. Many users of gas in cryogenic containers complain to their suppliers that the loud activation noise startles their employees and causes work disruptions and results in damaged product.

The Whisper Valve is easily installed on the vent valve of any cryogenic container and silently relieves the container pressure slightly below the normally installed relief valve. Whisper Valve reduses the relief of gas pressure at a noise level less than 40dB, for reference the average library noise level is 30dB.

The Whisper Valve also reduces the gas losses of your cryogenic container to less than 48 cubic feet over 24 hours.

Whisper Valves are available in three settings, 230 psig, 350, psig, and 500 psig.

  • Reduces cryogenic relief valve blow-off noise to less than 40 dB
  • Easily installs to any cryogenic argon, nitrogen or carbon dioxide container
  • Available in three ranges to prevent most container noisy blow-offs
  • Reduces gas losses to less than 48 cubic feet per 24 hours
  • Convenient wall mount kit available
  • Standard CGA 295 inlet connection

For users of cryogenic gases, this could be exactly what you have been waiting for. Simply install the “Whisper Valve” on the vent port of your dewar, open the vent valve and enjoy the silence.