SDI Open Water Scuba Diver Practice Exam 2025 - Free Scuba Diver Practice Questions and Study Guide

The safety stop is a vital part of dive safety, primarily designed to allow excess nitrogen accumulated in the body to be released gradually. Nitrogen can dissolve into the body's tissues during the dive under increased pressure, and a safety stop enables divers to off-gas some of this nitrogen before surfacing. This step helps minimize the risk of decompression sickness, also known as "the bends."

Typically, a safety stop is performed at a depth of 5 meters (15 feet), which is a common practice recognized in scuba diving training. This depth is effective because it provides a sufficient pressure differential to aid in off-gassing while still being shallow enough to allow for a quick ascent in case of an emergency.

The other choices do not correctly define the purpose of a safety stop. Checking equipment functionality, practicing skills, or conducting final oxygen checks are important aspects of diving but are not the focus of what a safety stop aims to accomplish. The emphasis on reducing nitrogen levels and ensuring diver safety is what distinguishes the correct answer in this context.