PADI Advanced Open Water Practice Exam

Most symptoms of decompression sickness typically occur on the surface within one or two hours after a dive. This timeframe is important for divers to recognize because symptoms can develop gradually as nitrogen bubbles form in the body due to rapid decompression.

Following a dive, especially if it involves deep or prolonged exposure, nitrogen absorbed during the dive can come out of solution and form bubbles in the bloodstream or tissues when a diver ascends too quickly. While some mild symptoms may manifest immediately upon surfacing or within the half-hour mark, the majority of serious symptoms are often reported within that one to two-hour window. This is when divers are most vulnerable, as they may not immediately associate any discomfort with their recent dive activities. Understanding these timeframes highlights the importance of proper ascent procedures and adherence to safety stops to mitigate the risk of decompression sickness.