![]() are all based on the manufacturer's claims, which may be based on theoretical estimation, and not necessarily on test results. Any other information listed on the rope label is at the manufacturer's discretion. A CE/UIAA label indicates that the rope has passed the minimum tests only. While the CE/UIAA has set standards for these tests, all of the results are pass/fail. ![]() It is important to note that ropes lose elasticity, and their ability to absorb energy, when subjected to repeated falls. The testing procedure – dropping a 176 pound weight attached to an 8.25 foot length of rope a distance of 16.5 feet – yields a very severe fall which would be difficult to duplicate in any but the worst actual climbing situation. The number of test falls held indicates how many UIAA certified falls a given rope can sustain before breaking. Therefore, standards are presently being developed through the ASTM (American Society for Testing and Materials). The US government does not require ropes to carry a CE or a UIAA label, nor does it recognize the CE standards. The CEN adopted the UIAA rope standards, and ropes tested to CEN/UIAA standards now carry the CE mark. The CEN (Committee for European Normalization) now coordinates standards that are upheld throughout the European Community. Historically, the UIAA (Union International des Associations d'Alpinisme) was the international body that certified climbing ropes. However, low impact force is often associated with high rope stretch, which may increase the climber's chances of hitting a ledge or the ground. ![]() The UIAA specifies a maximum impact force of 2540 pounds for single ropes and 1760 pounds for double ropes.Ī rope with a low maximum impact force absorbs more of the energy generated in a given fall than a rope with a high maximum impact fore, thus transmitting less energy to the protection system and to the falling climber. Maximum impact force is the maximum load transmitted to the climber during a fall. A low static elongation is desirable for rappelling and hauling. Static elongation is the stretch of a rope when weighted with a 176 pound load. WARNING: SHARP EDGES ARE EXTREMELY DANGEROUS AND ARE THE MAIN CAUSE OF ROPE FAILURE. Use of double or twin ropes reduces this danger considerably. Note that sharp edges are extremely dangerous and are the main cause of rope failure. Smaller diameter carabineers or rock edges reduce the strength even further. For example, the breaking strength of a given rope over a carabineer with a diameter of 10 millimeters is approximately 30 percent less than the maximum breaking strength. Knots, bends, edges and falls all reduce maximum breaking strength. High breaking strengths are desirable, especially in static life support and rescue ropes. Maximum breaking strength is the load whereby a single strand of rope (free of knots or sharp bends) breaks. The sheath is braided tightly around the core and its primary purpose is to protect the core against abrasion, although the sheath also helps determine a rope's handling characteristics. The core is the main load bearing element, and largely determines a rope's major characteristics, such as maximum impact force, and number of test falls held. Climbing ropes utilize a kernmantle construction consisting of a core (kern) covered by a sheath (mantle). Static ropes are not climbing ropes – never use a static rope for climbing or any application where dynamic loads may be encountered. Although static and dynamic ropes look the same they are not interchangeable. Static ropes, such as those used in rescue work are designed with minimal stretch and should never be used for climbing. Ropes used for climbing are dynamic – they are designed to stretch when fallen on, absorbing and dissipating the energy generated by the fall. An understanding of the design and construction of ropes as well as knowledge of their selection, use and care, is crucial to reducing the risks associated with their use. It is one of the few elements in the protection system that is not backed up by other equipment, and one that absolutely must not fail. United States Search and Rescue Task ForceĪ rope is an indispensable lifeline for a climber, rescuer, etc.
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