From Longman Dictionary of Contemporary Englishdecompression chamberˌdecomˈpression ˌchamber noun [countable] TTWa special room where people go after they have been deep under the sea, so that their bodies can slowly return to normal air pressure
Examples from the Corpus
decompression chamber• Once the inner door is closed and sealed, the bell is recovered to the surface and locked on to a decompression chamber.• This surface interval between leaving the bell and entering the decompression chamber, became a point of contention within the medical profession.• As with the basket, divers are recovered from the water to the surface, where they transfer to the decompression chamber. 