Submarine Escape Training involves hyperbaric exposures of up to 4 bar with a rapid decompression phase. Particular attention must therefore be paid to the respiratory and ENT systems, as well as other conditions which may prejudice the safety of hyperbaric exposure.
A trainees medical history will be screened and a strict medical must be passed before pressurised training can take place.
All trainees will complete a 9 metre familiarisation dive in a recompression chamber.

In order to make any escape from a submarine you will first of all have to open one of the escape hatches. Unfortunately there will be many tons of seawater pressing down on the upper hatch and the only way to open it is to equalise the pressures inside with that on the outside. This can be done by either flooding the whole escape compartment and then doing a Rush Escape, or by flooding the escape tower, either way the problem arises that you are now breathing air at increased pressure which means that your lungs will contain more air than they can safely hold here at the surface. As you make your escape and rise through the water the surrounding pressure reduces allowing the air inside your lungs to expand.