Of course, a surface interval is the period of time that a diver stays out of the water between two dives. During this time, the nitrogen absorbed during the first dive will be released from a diver's body. After 24 hours all the residual nitrogen is considered to be off-gassed. An old diving cliche goes: 'scuba diving is live, everything else is surface interval'. So if life is diving, the website you go to while not the diving should be called surface interval, right? That's why this website is called surface interval. And what is surfaceinterval.co? A scuba diving review website. At the moment there are 2000+ dive businesses listed. Dive centers, liveaboards, resorts, and shops. We want to be the website you instantly check when you are making new dive plans.