What role does pressure play in the risk of decompression sickness?

Pressure plays a vital role in the risk of decompression sickness because it affects how gases are absorbed in body tissues while diving. At higher pressures, such as those experienced while diving, the body absorbs more nitrogen from the air you breathe, as nitrogen is a component of the diving gas mixture. The increased pressure forces more nitrogen into the tissues, leading to a higher concentration of nitrogen dissolved in the blood and body tissues.

When a diver ascends to lower pressure, the solubility of nitrogen decreases, and the dissolved nitrogen can form bubbles, potentially leading to decompression sickness. This phenomenon is referred to as "the bends," where nitrogen bubbles can generate pain or serious medical conditions. Consequently, the absorption of nitrogen increases under higher pressures, thereby raising the risk of decompression sickness during the ascent when pressure is reduced.

In essence, the relationship between pressure and nitrogen absorption is a critical factor in managing diver safety. Understanding this allows divers to plan their ascent rates and decompression stops more effectively to minimize the risks associated with rapid changes in pressure.