This section provides technical information about the features of our ropes. Read each section to see the features that apply to some or all of our dynamic ropes and to determine which features work best for your application.
- Fall Rating/Fall Factor
- Impact Force
- Static Elongation
- Dynamic Elongation/Extension
- Dynamic Rope Use
Weight is measured in grams per meter (g/m) and can be a good indicator of the actual diameter of a rope. When comparing ropes of similar diameter from different manufacturers, a rope that varies significantly in weight may actually be over (or under) sized in actual diameter causing them to be incompatible with auxiliary equipment.
Dynamic ropes are often used in “lead” climbing situations where a severe fall in excess of a factor .25 could occur. Fall factors are calculated by the maximum distance a person could fall, divided by the length of the rope attaching the person to the anchorage point. In the case of lead climbing, the anchorage point may be fixed or removable gear that the person climbs above, creating the potential for falls that create a huge impact force. Please see the diagram below to get a better understanding for how to determine fall factor levels. It is the same whether using lanyards or dynamic ropes.
The UIAA test for dynamic ropes consists of a factor 1.8 fall over a simulated 10mm carabiner edge. Single and Half ropes must withstand a minimum of 5 successive drops while Twin ropes are tested in pairs and must hold a minimum of 12 drops. The number of actual drops a rope withstands before it breaks becomes its fall rating. Keep in mind that fall ratings for Single ropes are not directly comparable with fall ratings for Half and Twin ropes. Single ropes and Twin rope pairs are tested with an 80 kg (176 lb) test mass while Half rope is tested as a Single rope but with only a 55 kg (121 lb) test mass. Note that the field use is quite different from lab testing. While a higher fall rating is better, the actual figure should not be taken too literally and good judgment as well as consistent inspection practices should be used for retiring a rope (See “CARE AND MAINTENANCE” section of the Dynamic Rope Manufacturer’s Instructions).
The most important consideration in selecting a rope, Impact Force, refers to the amount of energy that a rope transmits to the climber and to the protection at the moment the fall is arrested. Falls are as described under Fall Rating, listed above. A maximum of 12 kN (2,700 lb) force is permitted for a Single and Twin ropes. Impact force for Half ropes must be below 8 kN (1,800 lb). Consider impact force in relation to other test results. Ropes with a high fall rating and low impact force rating can be relied upon to absorb energy better, fall after fall.
This test measures elongation for a rope under and 80 kg (176 lb) load - no drop, just a hang. Elongation must not exceed 8% (10% for Half ropes). The closer your rope is to the maximum, the greater its force absorption capability.
Rope extension is a key measurement that dictates the happy medium between falling on a bungee cord vs. hitting the end of the rope with a snap. When climbing on a rope with high extension, for the first several feet of a climb you may be at risk of hitting the ground due to stretch. The UIAA test method measures actual rope elongation during a fall and must not exceed 40%. This figure goes down with age, so the closer your rope starts to the 40% maximum, the longer active life your rope should have.
Many climbers assume that a thin diameter also indicates lightweight - which has spurred some manufacturers to take some liberty in reporting diameters. It is also enticing to have a rope with a small diameter moniker and number of falls that compete with fatter ropes. Consider diameter in direct relation to weight if you want to know how many fibers are really in a rope. In general, thicker diameters, such as 9.4mm and thicker, will wear longer. Diameter of a rope also determines if it is designed for twin, half or single use (see “Dynamic Rope Use” section below).
When choosing a length of a dynamic rope, you should consider where and how it will be used. Often you can use a 60m rope for most climbs, either top roping or trad. Many routes are set with this length in mind. Sometimes you will need more rope to get to a solid belay or to rappel all of the way to the ground. Climbing guides will often explain details of a route where you might need that extra length of rope. Using Twin or Half ropes can give you more options if you are unfamiliar with a route or get off route.
|1. Twin ropes combine the ease of Single rope use with the long pitch advantage of Half ropes… and the ability to shift half the rope load to your partner on the approach. Both ropes are clipped every time.|
|2. Half ropes, once known as “double” ropes, are popular among traditionalists and mountaineers. They are most useful for long routes, reduced rope drag, rappel descents, and an extra measure of confidence where there is a likelihood of rope damage. Half ropes are also recommended where pro is questionable, such as snow and ice routes.|
|3. Single ropes are the easiest to clip and belay, and for this reason are most popular with sport climbers. Single ropes are also used by trad climbers.|