Immersion Proof Breathers, also called protective vents, are “free breathers” that permit air pressure equalization, but keep out liquid water.

Immersion Proof Breathers Characteristics and Applications

Membrane keyboards and similar pressure sensitive equipment are often required to operate under adverse environmental conditions, one of which might be immersion under water. This has resulted in a need for a breathing device that permits air pressure equalization, but protects the equipment from liquid water intrusion.

AGM offers a wide range of Immersion Proof Breathers designed to meet these requirements for various applications.

Immersion protection can be provided for liquid water depths of up to 1 meter for as long as 24 hours. Over shorter periods, some Immersion Proof Breathers can withstand water pressure differentials up to 15 psig. Typical operating temperatures are -40°F to 257°F.

Breather flow rates vary from 150 cc per minute to 5000 cc per minute at 1 psig differential.

Solvent and oil resistant breathers are available.

Typical applications include:

  • Computer keyboards
  • Meteorological instruments
  • IP enclosures
  • Gearboxes and transmissions
  • Hand held terminals
  • Battery housings
  • Azimuth sealed devices
  • Equipment needing protection from hose down requirements.


No. Immersion Proof Breathers block the passage of liquid water but do not stop water vapor and for more information on how these breathers work see characteristics and applications.

That depends on the rating of the specific breather. Generally, the submersion time is a minimum of one hour.

That depends on the rating of the specific breather. However, there are breathers that are rated to a depth of 1 meter.

Yes. The smallest breathers that we currently offer are the mini-immersion breathers. Please contact AGM to ask about custom sizes.

This depends on the size and type of breather. They generally have low flow rates (a few cc to a few hundred cc per minute).

No. These breathers are also referred to as “free breathers” as they are always open.