How to Use a Carabiner

Make sure the force being applied to a carabiner is always on the long axis no matter what you use it for, whether you are equalizing a three-point anchor or belaying your partner. Never try to apply weight to it in a horizontal manner and never apply force to the gate.

Use locking carabiners for belaying, rappelling, prusiking, clipping into anchors and any other task in which you are putting your direct weight on the carabiner.

Check the gate periodically to make sure that it opens and closes smoothly. The gate of a carabiner should be able to open easily, even if under weight, and should not wobble from side to side when open. The hinge, in other words, should be solid. WD-40 can sometimes help clean up a hinge. Make sure to boil the carabiner for 20 seconds after using such a cleaning agent to remove it.

Never use a carabiner that has fallen off a cliff onto a hard surface. There may not be any visible damage to the carabiner, but it doesn't mean there isn't any.

Substitute two double-oval carabiners for a locking carabiner only in such a way that the two gates are opposite and form an X when opened simultaneously.

Clip a locking carabiner to the belay loop on your climbing harness and loop the rope through it as well as your belay device (such as an ATC). If it is a pear-shaped carabiner the smaller end should be on your belay loop and the rope should be fed through the larger end. This is the most basic but also the most frequent use of carabiners in climbing.

Only use non-locking carabiners for things such as connecting the rope to protection on a wall of rock or ice. Runners are two non-locking carabiners connected by a length of webbing. These are used to easily clip to the protection with one end and clip your rope onto the other without having to use both hands. These should never replace the protection itself (bolts, nuts, chocks, cams, ice screws) but should only be used as a connector.