The risk of decompression illness due to ascending too fast could be addressed by associated equipment; any other escape requirements, such as means of summoning help once the surface was reached, were not considered.

If the bag becomes deflated while the wearer is on the surface awaiting rescue, it can be refilled (for use as a lifejacket) by opening the non-return valve and blowing through the mouthpiece.

This emergency bag was inflated by an "Oxylet" canister inside it - a small steel oxygen cylinder which was opened by breaking its weakened neck and wrenching sharply.

[citation needed] It also had a speed-retarding drogue, which was a rubber apron unrolled and held out horizontally by the wearer as he ascended, dramatically reducing his speed of ascent through water resistance to avoid decompression illness.

In WWII it was also notably used by the Underwater Working Party at Gibraltar led by Lt. Lionel "Buster" Crabb, and worn at times by frogmen piloting 'Sleeping Beauty' Motorised Submersible Canoes.