Climbing ropes are made to absorb the force of a fall. To absorb the force of a fall, ropes must stretch. The ability of a climbing rope to stretch is called the dynamic quality. Climbing ropes stretch under impact force, but should remain static under a load. The Union Internationale Des Association D'Apinisme (UIAA) provides a testing standard for climbing ropes. To pass the minimum requirements, ropes must not break after 5 test falls with 12 kN impact force. Ropes are made to conform to specifications. Climbing rope test specifications are listed below.
Climbing Rope Testing. Indicates the type of test performed. There are two types of tests: “single” or “half”.
- The "half rope" test is performed using 2.5 meters of climbing rope. A 55 kilogram weight is attached to the rope. The object is dropped 4.8 meters.
- The "single rope" test is performed using 2.5 meters of climbing rope. An 80 kilogram object is attached to the rope. The weight is dropped 4.8 meters.
Impact Force. This is the amount of force a climbing rope is able to absorb. high numbers indicate more force is transferred to the climber. Low numbers indicate better performance. The highest acceptable impact force is 8 kN for the half rope test and 12 kN for a single rope test.
Elongation. This defines the dynamic qualities of the climbing rope. Elongation is the length a climbing rope will stretch. It is expressed as a percentage. The test is performed by attaching an 80 kilogram object to the rope. The rope’s length is measured with the object attached. The maximum elongation for single ropes is 8%. The maximum elongation for half ropes is 10%.
Number of Falls. This test is performed by attaching an 80 kilogram object to a climbing rope. The rope is 2.8 meters long. The object is dropped 5 meters. This test is repeated until the climbing rope breaks. Ropes must survive 5 falls to pass the test.
Usage. The type of climbing. Different types of climbing require different characteristics in the rope.
Weight per meter. Weight in grams for a meter of climbing rope.
Center Marked. This is listed as “yes” or “no”. Some climbing ropes mark the center.
Length. Measured in meters.
Thickness. Measured in millimeters.
Water Resistance. characteristics of a climbing rope to repel water.
Care of Your Climbing Rope
- Do not step on your climbing rope, and don't let anyone else step on it. The abrasion and dirt will weaken the climbing rope.
- Keep your climbing rope dry, even if it is water resistant. They become more susceptible to abrasion when wet. The abrasion causes it to lose strength. You can purchase a water resistant treatment for your climbing rope. Water resistant treatments are sometimes called a "hydrophobic" treatment.
- When you finish climbing, wipe your rope with a moist cloth.
- Store your rope in a cool, dark, and dry location.
- Keep the climbing rope clean. If you need to wash it, use cold water and a rag. Dry it by hanging it on a clothesline.
- Check your rope. Before climbing, look for signs of wear or damage.