What is the purpose of a safety stop during ascent?

The purpose of a safety stop during ascent is to allow the body to release nitrogen safely. When divers breathe compressed air while diving, nitrogen from the air dissolves into their tissues under pressure. As a diver ascends, the pressure decreases, and if they ascend too quickly, the nitrogen can form bubbles in the bloodstream and tissues, leading to decompression sickness, also known as "the bends."

A safety stop, typically performed at a depth of around 15 to 20 feet for about 3 to 5 minutes, provides the diver with the necessary time for the nitrogen that has been absorbed into the body to safely off-gas, reducing the risk of bubble formation and related complications. This practice is a vital part of safe diving protocols, contributing to the diver's overall well-being and safety after a dive.