What is the significance of surface intervals during diving?

Surface intervals are critical periods between dives that enable the body to off-gas nitrogen accumulated during previous dives. When divers go underwater, their bodies absorb nitrogen from the air in their tanks due to increased pressure. After resurfacing, it is essential to allow time for the body to expel this excess nitrogen to reduce the risk of decompression sickness.

During a surface interval, the diver’s tissues gradually release the nitrogen absorbed at depth. This off-gassing is a natural process that decreases nitrogen uptake and mitigates the risk of bubble formation when ascending or when performing subsequent dives. Properly planned surface intervals contribute significantly to diver safety by allowing a healthy amount of time for this physiological adjustment to occur.

While socializing can be a pleasant aspect of a surface interval, its primary significance does not lie in that purpose. Similarly, although certain guidelines recommend mandatory surface intervals based on dive profiles, they are not legally enforced for all divers. Lastly, surface intervals do not replace the necessity for safety stops, which are important for further prevention of decompression sickness at the end of deeper dives. Therefore, the main importance of surface intervals is the body's need to eliminate excess nitrogen effectively.