What is the minimum surface interval required to avoid a repeat dive?

The minimum surface interval required to avoid a repeat dive is based on the need to allow nitrogen that has accumulated in the body during a dive to be safely eliminated before embarking on another dive. A surface interval of at least 10 minutes is generally recommended by diving organizations to minimize the risk of decompression sickness, commonly known as "the bends."

During a dive, as divers breathe compressed air, nitrogen is absorbed into body tissues. If divers ascend too quickly or dive again without allowing sufficient time for nitrogen off-gassing, they risk complications. The 10-minute surface interval provides a baseline timeframe that allows the body to start off-gassing excess nitrogen, even if it is not completely eliminated.

Longer surface intervals may be required depending on factors such as the depth and duration of previous dives, the type of diving being done, and the diver's individual physiology. However, a minimum of 10 minutes is established as a safety measure to help reduce the likelihood of nitrogen-related injuries during repeated diving activities.