than the height of the jumping platform to allow it room to stretch. When the cord becomes taut and then is stretched, the tension in the cord progressively increases. Initially the tension is less than the jumper's weight and the jumper continues to accelerate downwards. At some point, the tension equals the jumper's weight and the acceleration is temporarily zero. With further stretching, the jumper has an increasing upward acceleration and at some point has zero vertical velocity before recoiling upward. See also Potential energy for a discussion of the spring constant and the force required to distort bungee cords and other spring-like objects. The Bloukrans River Bridge was the first bridge to be used as a bungee jump launch spot in Africa when Face Adrenalin introduced bungee jumping to the African continent in 1990. Bloukrans Bridge Bungy has been operated commercially by Face Adrenalin since 1997, and is the highest commercial bridge bungy in the world. In April 2008, a 37-year-old Durban man, Carl Mosca Dionisio, made bungee jumping history when he jumped off a tower attached to a bungee cord made entirely of 18,500 condoms. Equipment The elastic rope first used in bungee jumping, and still used by many commercial operators, is factory-produced braided shock cord. This special bungee cord consists of many latex strands enclosed in a tough outer cover. The outer cover may be applied when the latex is pre-stressed, so that the cord's resistance to extension is already significant at the cord's natural length. This gives a harder, sharper bounce. The braided cover also provides significant durability benefits. Other operators, including A. J. Hackett and most southern-hemisphere operators, use unbraided cords with exposed latex strands. These give a softer, longer bounce and can be home-produced. Accidents where participants became detached led many commercial operators to use a body harness, if only as a backup for an ankle attachment. Body harnesses generally derive from climbing equipment rather than parachute equipment. The highest jump In August 2005, AJ Hackett added a SkyJump to the Macau Tower, making it the world's highest jump at . The SkyJump did not qualify as the world's highest bungee as it is not strictly speaking a bungee jump, but instead what is referred to as a 'Decelerator-Descent' jump, using a steel cable and decelerator system, rather than an elastic rope. On 17 December 2006, the Macau Tower started operating a proper bungee