How does the bends in scuba diving affect the people?

Answer 1

At depth, the diver is breathing air that is compressed. At pressure, this isn't a problem. But, as you start to surface, and the pressures decrease, the oxygen can "come out of solution". This requires divers to come up very slowly. The general rule of thumb is if you are going up faster than your bubbles that you exhale, you are going WAY TOO FAST. If you come up too fast, that oxygen that comes out of solution forms bubbles in your blood. Depending on several factors (time at depth, what depth, and a few other things), these bubbles in the blood can be as simple as pains in your joints, to causing death. I have heard of one extreme account where the diver's blood was essentially foam when they surfaced ... and did not survive.

Also, any amount of the bends will stop you from diving for quite some time.