Define "residual nitrogen" and its implications.

Residual nitrogen refers to the nitrogen that remains dissolved in a diver's body tissues after the dive is completed. During a dive, divers are exposed to increased pressure, which allows more nitrogen to dissolve into their body tissues from the breathing gas. When ascending, the pressure decreases, and nitrogen begins to come out of solution. However, not all nitrogen is expelled immediately, leading to residual nitrogen in the body.

Understanding residual nitrogen is crucial for divers because it has direct implications for safety, particularly concerning the risk of decompression sickness, commonly known as "the bends." If a diver ascends too quickly or engages in a subsequent dive without allowing sufficient time for the nitrogen to fully leave their system, the residual nitrogen can form bubbles in the tissues or bloodstream, which can cause injury.

Proper dive planning includes monitoring no-decompression limits and allowing adequate surface intervals, factors that help manage residual nitrogen levels in alignment with dive tables or computer algorithms. This ensures divers maintain safe nitrogen levels in their bodies, minimizing the risk of complications upon ascending or when participating in repetitive dives.