When do symptoms of lung-expansion injury typically appear compared to decompression sickness?

Symptoms of lung-expansion injury generally manifest immediately after surfacing from a dive. This condition arises when a diver ascends too quickly, leading to a rapid increase in volume of the air in the lungs, which can cause tissue damage and air embolisms. The immediate onset of symptoms can include chest pain, difficulty breathing, and other respiratory distress signs.

On the other hand, decompression sickness, often referred to as "the bends," typically appears more slowly, depending on factors like the depth of the dive, how long a diver was under pressure, and the ascent rate. Symptoms can take hours or even days to develop after surfacing, as they are caused by the formation of nitrogen bubbles in the body due to decreased pressure.

The understanding of these phenomena is crucial for divers, as it emphasizes the importance of ascending slowly, conducting safety stops, and being aware of dive profiles to minimize risks.