Correction

A few months back our editor fell and reported that his lower carabiner broke in the fall. He was 10cm from smashing his head into the rocky ground. After careful investigation it became clear that he had clipped the bolt with the lower end of the carabiner and that it was this that broke, which is much more common. At first there was a suspicion of a "bad" carabiner but then it was discovered that the carabiner had got stuck in the bolt between the screw and the bolthole (see picture for an extreme case). If this happens the carabiner only holds for about ONE THIRD of the force (3.5KN instead of 10KN). A 4m fall(2m above the last clip) at 15 meters gives a fall factor of about 0.27 and a force of 5KN, which will cause the carabiner to break if it is stuck like shown here. In addition to the manufacturer testing, an 8a associate has tested this in his lab and the above is true for most type of carabiners, and not just the brand used by our editor. Take care out there!