How should the diver respond to experiencing a rapid pressure change?

When a diver experiences a rapid pressure change, the appropriate response is to equalize pressure in the ears and ascend slowly. This approach helps to prevent barotrauma, which can occur if the pressure in the middle ear is not equalized with the surrounding water pressure. During a rapid ascent, the pressure on the diver's body decreases quickly, potentially leading to discomfort or injury.

Equalizing the pressure in the ears—often achieved by performing the Valsalva maneuver, where the diver pinches their nose and attempts to breathe out—helps to balance the internal and external pressures. Following this, ascending slowly allows the body to adjust to the changing pressure gradually, reducing the risk of decompression sickness and other injuries associated with rapid changes in pressure.

Holding their breath can be dangerous, as it may lead to lung overexpansion injuries if the diver ascends without allowing air to escape from their lungs. Ascending immediately without equalization also poses significant risks, including ear damage. Using a breathing apparatus is not necessary in this scenario unless the situation requires it, and proper procedures should always be followed to ensure safety during diving activities.