Why is diving too deep dangerous?
As you descend, water pressure increases, and the volume of air in your body decreases. This can cause problems such as sinus pain or a ruptured eardrum. As you ascend, water pressure decreases, and the air in your lungs expands. This can make the air sacs in your lungs rupture and make it hard for you to breathe.
How dangerous is scuba?
Diving does entail some risk. Not to frighten you, but these risks include decompression sickness (DCS, the “bends”), arterial air embolism, and of course drowning. There are also effects of diving, such as nitrogen narcosis, that can contribute to the cause of these problems.
Can you be crushed by water?
Water doesn’t squish — a cubic foot of liquid water always weighs 64 pounds, and 64 pounds of liquid water always takes up one cubic foot of space. Deep water would squeeze the air in your body, especially in your sinuses and lungs. Since air is compressible, these spaces would eventually collapse.