Why is it important to avoid rapid ascent during night dives?

Avoiding rapid ascent during night dives is crucial primarily because it can lead to decompression sickness. When a diver ascends too quickly, nitrogen that has been absorbed into the body under higher pressure is released too rapidly. This can create bubbles in the bloodstream or tissues, leading to serious health issues. At night, visibility is already limited, and the risk of accidents matters more since divers may be less aware of their ascent rate. Therefore, ascending slowly allows the body sufficient time to safely eliminate the nitrogen and reduces the chances of experiencing decompression sickness, which can have severe consequences for the diver’s health and safety.

Although there are other considerations related to night diving, such as awareness of surroundings to avoid getting lost, care for marine life, and managing dive equipment like lights, the primary health concern centers around preventing decompression sickness, making it the key reason to avoid rapid ascent during such dives.