include additional shock absorbing elements which are not included in the test standard, such as the body of both the climber and belayer, elasticity of their harnesses and anchor materials, and friction between the rope and the belay device, and any protection pieces. Single ropes must sustain at least 5 such falls before breaking, and a rope that can sustain more than 9 falls is considered a 'multifall' rope. In practice, climbing ropes rarely if ever break due to a fall alone- all documented rope failures involve the rope being cut or damaged, for example by abrasion against a sharp rock edge. Ropes are especially vulnerable to being cut while they are weighted with the body of the climber, and moving over a sharp edge (for example if a following climber is resting his weight on the rope, or using the rope for assistance, while swinging or traversing under a roof, while being belayed from above). In general, thicker ropes will be stronger and more durable, and have a higher fall rating. Rope care and maintenance Modern ropes are made from nylon and don't require a great deal of maintenance. Ropes that are frequently used are often inspected for cuts, abrasions, or frayed areas; any cut or fraying that passes into the core of the rope is cause for concern. Ropes can also be washed to clean them of any extensive dirt or grime. Ropes must also be kept away from chemicals or seawater which may damage them, or stored for long periods in direct sunlight which can cause UV damage over time. Every fall lessens the amount of impact a rope can later absorb, and hard falls can seriously compromise the strength of a rope, without showing obvious signs of wear. One definition of a 'hard fall' is a long fall (> 10–15 meters) with a fall factor greater than one. Manufacturers often recommended that ropes be retired if they sustain an extremely hard fall, even if they do not show outward signs of wear. See also Climbing equipment Climbing rope Fall factor Static rope References Notes Sources Spelean.com.au Caving equipment Climbing equipment Mountaineering equipment Ropes