Competitions in Underwater Orienteering take place in deep, open water bodies and over various distances, as prescribed in the competition rules. Competitors must, while remaining completely submerged without any contact with the water surface, reach specific points or pass specified points.Competitions in underwater orienteering are based on the principle that orienteering and searching tasks are performed under water with the aid of a compass and distance meter.
The competitor may only use his/her own muscular strength to propel him/herself. The breathing apparatus used may only be filled with normal compressed air. Enrichment with oxygen is not allowed. The only contact with the surface of the water allowed is a buoy line and a safety buoy. A snorkel and/or knife is, despite earlier safety rules, not compulsory.