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anchor testing rig 18-Sep-2012 At 3:16:52 PM TonyB

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On 11/10/2010 One Day hero wrote:
>On 11/10/2010 davidn wrote:
>>Also worth noting that for those manufacturers using 3sigma (DMM, Black
>>Diamond, some others), they have confidence that 99.7% (or more) of products
>>won't break within the noted range. That doesn't say when it will break.
>
>More psychobabble. There is no "noted range", there is a single strength
>value. Almost all the biners will break above the stated value by a little
>bit..........double is not a little bit!

It's an old post but worth a comment. "3 sigma" is not "psychobabble" and is probably a reference to this from BD http://info.rockrun.com/articles/3-sigma-rating.html. It's not psychobabble but BD do show a lack of understanding of quality in manufacturing.
"A little bit" is just ODH's usual psycho babbling nonsense.

Lots of wonderful articles here, from the world's leading statistician in quality in manufacturing:
http://www.qualitydigest.com/read/content_by_author/12852
Here's a relevant one to start:
http://www.qualitydigest.com/inside/quality-insider-article/myths-about-process-behavior-charts.html
This one relates to BD's 10% comment
http://www.qualitydigest.com/inside/twitter-ed/part-spec.html