A carabiner strength chart is one of those things worth understanding before heading out for climbing or any outdoor adventure Each carabiner has three different strength ratings marked on its spine: the Main Axis, the Minor Axis and the Open Gate rating. You also call the Main Axis the main direction, while the Minor Axis is sometimes called the transverse direction or cross-loaded position.
The highest number usually is the strength rating for the Main Axis. It shows how much force the carabiner lasts when you load it end-to-end with the gate closed. For instance, a rating of 24 kN means it can hold around 5,400 pounds.
How to Read Carabiner Strength Ratings
To convert kiloNewtons to pounds, multiply the kN value by 224.8; so a 20 kN carabiner lasts roughtly around 4,500 pounds.
UIAA standard for carabiners requires static strength of more than 20 kN, which equals holding over 2 tons before it breaks. That far surpasses the force in the worst imagined fall during a climbing accident. Markings of CE and UIAA show on the long side of the carabiner to confirm it meets those standards.
A carabiner must be closed to reach its full strength. An open gate reduces the strength value by 60% or more. A symmetrical oval carabiner has 23 kN closed and only 7 kN open.
A huge differense.
Common ratings for carabiners are 5 kN, 12 kN, 25 kN or without rating. You use them for various goals like canoeing, sailing and arboriculture. Non-rated carabiners lack the force and trust needed for climbing, so you avoid them for that.
The shape of a carabiner affects its strength and weight. Its size is defined by the length of the Main Axis, the amount the gate opens and the amount of rope it can fit in its basket. Light weight full-strength micro carabiners are best for arranging and sorting gear.
Everything used for climbing. As rope, webbing, carabiners, anchors and protection, is made to absorb force from a fall. Every such gear has a kN rating.
That does not consider wear and tear, so always check everything before use and replace what is too worn. The maximum force of a carabiner is in its spine, where come the two different kN ratings. Many makers use 3-sigma tests to set their minimum breaking strength.
You find the ratings directly on the side of the carabiner or in their spec sheets.
