What is the recommended ascent rate for deep diving?

The recommended ascent rate for deep diving is set to promote diver safety by minimizing the risks associated with decompression sickness, also known as "the bends." An ascent rate of no faster than 9-10 meters (30-33 feet) per minute is ideal because it allows the body to safely off-gas inert gases, particularly nitrogen, that have accumulated in body tissues during the dive under pressure.

When divers ascend too quickly, the rapid decrease in pressure can lead to gas bubbles forming in the bloodstream or tissues, which can cause serious health issues. The guideline of 9-10 meters per minute provides a balance between efficient ascent and sufficient time for the body to adapt to the decreasing pressure.

Other ascent rates, such as those exceeding 10 meters per minute, significantly increase the potential for decompression sickness and are therefore not recommended. An ascent rate of 5 meters per minute is more conservative but may unnecessarily prolong the ascent for experienced divers in controlled situations. The option indicating an ascent rate of 12 feet per minute may seem cautious but is not a metric commonly used for deeper dives, specifically where nitrogen narcosis and its related pressures are of concern.