help with understanding a UIAA test method

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 simondgee 22 Feb 2024

Im trying to understand a test method used for lanyards including adjustable under UIAA 109.
There are
Static strength 15kN min.
Dynamic test peak force must be under 10kN on an 80 kg FF2
But then there is a 'Slippage test for the adjustable lanyards', like the Petzl Connect, ...it consists of applying a 100N load between the ends and measuring slippage and for it to be under 50mm. Trying to undertsand the 100N (equivalent 10Kg) rationale ...10Kg is jack shit of of anything, The only thing that I can think is that is applying a light load to ensure it shouldnt creep? 
Suprised the tests dont require a static test of say 4-5kN to demonstrate that the adjustable lanyard wont slip in use and with moderate load.
Any wisdom to be shared? TIA

 gravy 22 Feb 2024
In reply to simondgee:

The 100N is the preload (presumably to pull the kinks out of the rope and set the device) at which point the position is measured. After that the force is then increased to 2kN and the slippage measured (from the 100N mark).

Post edited at 22:11

 David Coley 23 Feb 2024
In reply to simondgee:

Slightly off topic, but if the lanyard is subject to high forces, isn't some slippage a good idea to try an reduce peak force?

 beardy mike 23 Feb 2024
In reply to David Coley:

If the peak force is sub 10kN that's pretty acceptable given the situation. Remember that a dyneema sling is more than 24kN in a FF2, and that 10kn is a max, I.e. most will be less than that. I mean it's high but very survivable...

 Fellover 23 Feb 2024
In reply to simondgee:

I think there's probably confusion here because the UIAA pictorial representation of the UIAA 109 Belay Lanyards standard (https://www.theuiaa.org/documents/safety-standards/Pictorial_UIAA109%20Bela...) is not a good representation of the actual 109 standard (https://theuiaa.org/documents/safety-standards/109_UIAA%20Belay_LanyardV8_2...).

The pictorial standard has an image representing the slippage test and some text "100N slippage <50 mm", I think it's fair to say this is wrong. The text should really be "2kN slippage <50 mm". A few of the UIAA tests involve some kind of preload, which is normally not included in the simplified pictorial representation of the test.

OP simondgee 23 Feb 2024
In reply to David Coley:

Yes it used to 12kN in the standard but below 10kN is better and the new standard, which is the current maximum arresting force. It is at this point force limiting to protect the user, to some degree, and the anchor.

Equally there is a threshold below which you don't want it to slip... Otherwise it would slip with a normal in use static load. The sweet spot is between 5 and 10kN... I have seen the 5kN  cited but can't find that now and not really sure why for an adjustable lanyard like the connect why there isn't a minimum it must sustain before it slips.

OP simondgee 23 Feb 2024
In reply to Fellover:

That makes sense 

Apply 100N preload to create a relevant zero datum then load to 2kN and slippage must be under 50mm from the datum.

I'd still like to find the actual Petzl slip force rather than the standard. 


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