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General Climbing Discussion

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Dropped Biners... 26-Aug-2003 At 5:21:20 PM dodgy

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Ever seen "3 sigma" on your gear? (Black Diamond/Wild Country use it)

(From BD's website) "Engineers test a random sample of carabiners under international standards using a machine called a tensile tester, which literally stretches the carabiners until they break. They determine the average, or mean, breaking strength of the batch. From this data they also calculate the average deviation from the mean, called the "standard deviation," symbolized by the Greek letter sigma. The standard deviation represents the variation of breaking strengths within a given sample. If the biners are rated three standard deviations less than the average breaking strength, 99.87% of the biners will be stronger than the rating.

Having seen a #4 Camalot tested by BD it is just unreal what the gear will take, normally the slings will tear before the cam itself. The one I saw had folded sideways at least twice the rated load. Also remember that gear is tested in a "placement" which will not fail... If anyone can find me rock as reliable as the gear I use (old, new or dropped) I'll feel much better.