What is the acceptable range of surface interval for recreational dives?

The acceptable range of surface interval for recreational dives is generally considered to be 24 hours for recreational diving activities. This duration is important because it allows for adequate off-gassing of nitrogen that has accumulated in the body during diving. After completing a series of dives, especially deeper or longer ones, a 24-hour surface interval helps to reduce the risk of decompression sickness, as the body needs time to safely eliminate the excess nitrogen.

A longer surface interval, such as 48 or 72 hours, can offer even greater safety, particularly after multiple days of diving, but they are not strictly necessary for a single day of recreational diving, as the 24-hour mark is usually sufficient for most divers. Shorter surface intervals, like 12 hours, may not allow enough time for adequate off-gassing, especially if a diver has been at significant depths or engaged in repetitive dives, which increases nitrogen uptake. Thus, while longer intervals are better, the standard recommendation for recreational diving is the 24-hour surface interval for safety against decompression illness.