Answer from a manufacturer

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I sent my thesis to most of the manufacturers of PPE and one of them wrote an answer with a couple of arguments, why the lifespan should be limited. He gave permission to publish them anonymously and shortened. He said, it is his personal opinion and not approved by his company. I hope I did not change his ideas by shortening.


Reasons for a limited lifespan


Argument 1

Murphys Law: Storage and transportation increases the risk over the time that unforeseeable things happen: Chemical contamination, dirt, UV Radiation,…

Argument 2

“Normal” users are no experts in using PPE correctly. Therefore one can assume that we see negative influences due to misuse: (little falls, bending effects on carabiners,…) The normal user cannot assess these influences and when to discard the PPE.

Argument 3

PPE Regulation, EN and UIAA require a clear “lifespan of the product or how to assess it”.
Safety factors >2 are industry standard for riskproducts and therefore of course appropriate and right for mountaineering equipment.
In the USA the producer will face lawsuits if he does not provide clear lifespan.

Argument 4

All serious producers have – in addition to the standard procedures – aging tests (abrasion, UV, water, temperature,) usage tests (knots, dynamic and static tests), storage and transportation and abuse.
These factors are the risk factors for a “safe” lifespan.
The results of the laboratory tests match the producers lifespan.

Argument 5

“Newer” products are often safer than old products.

Argument 6

The tests of your masters thesis do not mirror all worst case scenario, therefore your theoriy “age is no discard criterion” is wrong. It is a minimal number of tests and only valid for these tests.

Argument 7


The tests in our company confirmed that the defined lifespan is correct.
 




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