Why is careful ascent important for divers?

Careful ascent is crucial for divers primarily because it helps to prevent bubbles from forming in the body's tissues and avoids the risk of decompression sickness, commonly referred to as "the bends." During a dive, divers are exposed to increased pressures, which allows them to absorb more nitrogen from the breathing gas. If a diver ascends too quickly, the reduction in pressure can cause the dissolved nitrogen to come out of solution and form bubbles. These bubbles can lead to serious symptoms and can affect various bodily functions.

Decompression sickness can manifest in severe pain, paralysis, or even death. Therefore, divers are trained in safety procedures that involve controlled ascent rates, often incorporating safety stops at various depths, so that any nitrogen absorbed can safely be released from the body while still managing the pressure differences. This careful management ensures the safety and health of the diver after coming to the surface.