Alice Springs has one of the highest rates of potentially fatal deep-sea diving sickness in Australia – despite being 1500km from the ocean. About four cases of the bends or decompression illness are reported in the town each year. Nearly all the diving accidents are caused by overseas visitors boarding planes almost immediately after deep sea diving on the Great Barrier Reef. They do not give their bodies enough time to recover and to prevent nitrogen bubbles forming in the blood and tissue. Dive trips off the Queensland coast often involved 14 dives in four days and intensive diving that can push people to the limit. Standard rules for divers recommend they not fly for 24 hours after repeated diving.