Scuba Diver Life describes how when someone dives deep below the water’s surface, the concentration of nitrogen in the bloodstream increases. If divers rise to the surface at a slow and steady rate, the pressure reduces slowly enough for levels to safely return to normal. Rising too fast, however, causes this nitrogen to form bubbles that can cause significant damage to the body and its delicate systems.
How Stuff Works compares this to opening a can of soda. When kept under pressure, the carbon dioxide gas in the liquid of the soda stays integrated, but as soon as the pressure is immediately relieved by opening the bottle, all of the gas immediately tries to escape in the form of bubbles.
The different types of DCS
Severe DCS typically occurs when rising from depths of more than 100 feet. When this happens, the nitrogen bubbles affect the nervous system. This can lead to damage to the brain (Cerebral DCS), the lungs (Pulmonary DCS) or other parts of the nervous system (Neurological DCS).
The less severe form of DCS can occur even at depths above 100 feet. Joint and Limb Pain DCS causes aching in the joints, while Cutaneous DCS causes a rash that may feel sore. While these types of DCS are not as dangerous, they may be warning signs for the more severe forms, and it is a good idea to still seek medical attention when experiencing these symptoms.