Why are carabiners required by the CE to hold 20 kN, yet sewn slings are rated to 22 kN, and lots of protection fails at 10 kN or less. Shouldn’t all gear have the same strength requirement?
—J. Jonstone, Charlotte, NC
The simple answer is because nuts, cams, carabiners, harnesses, ropes and every item of equipment in the chain of protection is made of
various materials, has a unique use, is loaded differently and subjected to different loads. You can’t apply one standard to all climbing gear any
more than you can use the same standard for a car’s airbag and tires. If all types of gear had the same rating as carabiners, their designs and functionality
would be compromised to the point of becoming unusable. For example, a micro nut that now breaks at the cable at 5 kN would, to achieve a carabiner’s
CE strength, require a cable so thick it wouldn’t fit through the nut itself. If all gear had the same strength rating, the rating would actually have
to decrease— not increase—down to the lowest common denominator, since nuts and cams could never achieve a strength equal to that of a
sling. Slings are required to test to 22 kN because it is practical and economical to manufacture them to that rating. So why not? Also, since slings
are used for all purposes from assembling a belay to clipping bolts, they need to be strong enough to never fail in any application, and do so even
after they have lost some strength from wear and tear. Gear Guy has spoken!
This article was published in Rock an Ice issue 228 (August 2015).