Number of reported diving incidents (1999–2013). Total number of diving incidents reported (left) in the period 1999–2013 in which the depth was not recorded (blue) or was recorded (yellow). Of those in which depth was recorded (right), the number of incidents involving dives to depths of less than 30 msw (orange) or greater than 30 msw (grey) is reported. Total number of reported incidents = 6,135. (Source: British Sub-Aqua Club incident database).