UKH

In a UKC lanyard review from about 6 years ago I came across these words:

’The downside of elasticated lanyards is that you don't tend to clip in and sit on them if resting…’, - which is very true, but got me thinking about what the actual ‘deployment force’ is on such lanyards, and whether you could/should weight them with body weight. I can’t find any data about the force or weight required to rip them, which also begs the question as to whether a very short low factor fall would rip?
Anyone have any data on this?
 

I don't think that's true anymore, unless you're pushing the weight limit of the set? Most brands describe hanging into the set at rest as a possibility, as long as you're not dynamically falling into it.

Industrial lanyards that have an max impact force of 6kn when they fully delpoy do not deploy until around 1.2-2kn force is applied and then only a tiny a bit (stitching starts to rip) body weight wont deploy them but it isnt good over a l;onger period of time.  

Iirc they should reduce the impact force to 6kN, so you'd probably need a force exceeding that to get them to rip. So for a static load, as long as you weigh under 600kg, you should be fine.

I use a similar but beefier setup to climb industrial structures for work with a shock absorber also rated to reduce the impact force to 6kn. They get tugged, weighted, battered and generally abused but in 15 years I've never seen the stitching start to rip. There's a part of me intrigued to jump off to see if they'd actually work.... but even 6kn is a lot of force to put through your body.

My bungee lanyards (well over 6 yrs old) state in the instructions that you can clip in and rest on them. Never tried though, somehow it feels scary and I prefer a cows tail made from a sling for the rare occasions when I need to rest in a suspended position.

I think more to the point, why would you be resting on it in the first place? I mean maybe I'm just oldschool, but in my 21 years of doing via ferrata I've never felt the need to rest on my set, or use gloves for that matter? All seems a bit odd to me to be honest. Maybe I've not been doing cray cray hard via ferrata as I mostly do it in the Dolomites where they are old school and just a pleasant enough way to go up a mountain, but I don't see the point? I mean I also don't really see the point of really hard "sport" via ferrata, just go climbing? It's safer...

I never said I intended to rest on the lanyards, I said I got to wondering what the deployment force was.

My 45 years of climbing are over after an accident 5 years ago, - via ferrata has proved to be a viable alternative that still gives me a challenge in the moutains.

6kN is the upper limit they're not allowed to exceed in testing set by the EN standard, in practice industrial lanyards typically blow at about 4kN.  I don't know, but I guess it's probably about the same for stitch-ripping via ferrata lanyards.

Otherwise I agree completely, sitting on them for a rest is a non-issue as is a teeny tiny slip.  4kN is less than 6kN, obvs, but it's still plenty.  If you hit the end of the lanyard hard enough to start blowing out the stitching in the shock absorber you're going to know about it.  I've tried it with a 70kg rescue dummy and it looked painful, there's no way I'm volunteering to test one myself!

Don't most modern VF kits have a separate loop for clipping in with?  I use an adjustable lanyard, which allows me to clip into the rungs of a ladder, say, without needing to remove the VF lanyard from the safety cable.

I've always taken the approach of not weighting mine, and using a cows-tail whenever I need to rest. As well as reducing wear and any potential for partial deployment of the shock absorber (real or imagined), I find t more convenient: At full stretch, the crabs on my elasticated VF kit are out of reach. 

You won't rip one by sitting on it.  I was overweight (all up with kit probably by about 1/3 over) on the old 100kg limit and I never deployed one just by sitting on it.

The loop for a resting krab is usually on the same side of the screamer as the lanyards are anyway.

Yes, and it is on the same side of the screamer as the lanyards are.

True enough, I was just getting at the point that I find the practice of sitting on your set an odd one, rather than saying you do it, seeing as some are built specifically with a loop for that purpose. Given that that's the case activation on the stitching will have to be 1.5 or more, and I would have thought that that will be pretty much across the board. Sorry I should have stuck to what you were asking! Re the second part - the thing I don't understand about sport VF is that it is substantially more likely that you will fall off and therefore quite likely that you will injure yourself seriously. Personally I don't like the odds and as I say would regard easy climbing, or even better seconding as safer.

Hi Fred.

here is the info you are after -https://www.edelrid.de/en/knowledge-base/sports/in-depth-knowledge-about-vi...

In short you can weight them fine, if you sit on the elastic arm over time the elastic will stretch and you may find they become a bit longer and harder to use. They used to recommend you left one elastic arm on the wire and thread the other round a staple and then clip it back in to the belay loop, this is easier to load the lanyard with out dropping on to it if the elastic arms is long/stretchy.

But now you are better to use the resting arm if your lanyard has one and leave both elastic arms on the wire, if you lanyard doesn't have one you can make one out of a short sling. if buying a lanyard get one with a resting arm as it saves faff and confusion with more than one thing attached to the belay loop.

I find myself resting on them a lot to take photos (I make a via ferrata guide) and it fine, I have never had to do it because I am tired. If you find yourself having to clip in a lot because you're tired, you're probably on a route that a bit too hard for you, it's more for ones offs and incase you find something harder than you thought it was going to be than planning to use it every time.

Cheers

Gloves help you not cut/puncture yourself on broken wire strands on easy 'oldskool' ferrata.

Be that as it may, I can't say I've ever had that problem. I tend to use the rock more for climbing rather than pulling on the cable though so that would explain it. Guess it just depends on the way you climb them...