Wreck-Diving.org

when you dive the deeper you go, the higher the pressure of water surrounds your body. For every tem metres or depth it takes twice as much air to inflate your lungs as it would on the surface.

As you go deeper your lungs your lungs have a lot denser amount of air in them. That air contains approx 79% nitrogen which the body has to deal with. The more time your lungs spend breathing this dense air the more nitrogen builds up in your system.

To prevent this nitrogen build up becoming dangerous, divers must slowly ascend, this slowly lessens the density of the air in the lungs as the surrounding pressure decreases and the body is able to slowly release the built up nitrogen. This is called decompression.

When the diver has surfaced and is breathing unaided, they will still have some excess nitrogen in there system depending on how long they have been underwater and how deep they have been.

The deeper you go, the more pressure will be on your respiration system. The weight of thousands and thousands of tons of water will be squeesing the air out of you.

hard to breathe under water!