Climbing with twin ropes
Two is better than one! This common phrase also applies to climbing. Twin ropes are used as double strands for both ascents and descents. Their diameter can range between 7 and 8 millimetres, so they’re very thin and should therefore never be used individually whilst climbing. Since you’re combining two strands, the twin rope system is guaranteed to be safe. Twin ropes require you to hang them together at every point. It’s highly unlikely that both ropes get damaged at the same time due to excessive stress, sharp edges or falling rocks, so safety is enhanced. Plus, twin ropes allow for a long rappel, and they're mainly used for alpine climbing.
What makes a good twin rope
Since your life will depend on the twin ropes, they should be high-quality and very reliable. To ensure this, twin ropes are tested according to the European safety standard EN 892. During the standard test falls, the twin ropes must withstand 12 drops with an 80 kg load without tearing. The rope also can’t be stretched more than 40 percent in the case of a fall and 10 percent under the normal load to ensure optimal safety. Another thing to look out for when purchasing twin ropes is that they have a DWR treatment. This is especially important in alpine climbing because it prevents moisture and dirt from penetrating inside. As a result, the lifespan of your twin ropes will increase.