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The UIAA says that you should retire your gear after a major fall is a fall with fall factor > 1.77.

Now I was wondering if this criterion is the same for all kinds of material ?

  • Dynamic ropes
  • Semi-dynamic ropes
  • Static ropes (or slings)
  • Your metal gear

I've read the tips for protecting your equipment on the Petzl site and they don't seem to make a distinction between the above.

Nick
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    You don't want to fall on a static rope at all, not if your appreciate the use of your lower limbs. :) –  Aug 29 '14 at 09:18
  • @Liam, I was just going to say that in a comment :p. A fall factor 1.77 in a static rope will leave you completely broken :p. But of course If you do a fall factor of 1.77 in a combined system, this might be a relevant issue? – Nick Aug 29 '14 at 09:19
  • What's your thinking behind this? I'm not sure what your getting at? Fall factors are only relevant on dynamic ropes, the gear is involved but isn't directly relevant. Are you talking about when to retire gear/ropes? –  Aug 29 '14 at 09:22
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    @Liam, it's indeed about the retireing ;). See edit – Nick Aug 29 '14 at 09:28
  • I'm pretty sure there is an equation to convert fall factor into Kn force. I'll try and dig it out –  Aug 29 '14 at 09:42
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    Yeah, that's true. I derived one yesterday using the "simple harmonic oscillator"-model (which yields an overestimation). But I tought that the UIAA had standardised tests at f=1.77 which was the limit. Or am I wrong in this ? – Nick Aug 29 '14 at 09:52
  • I think this only applies to ropes? Gear (in trad) can vary considerably. I've got some small nuts that will only hold 8Kn –  Aug 29 '14 at 10:08
  • Also a rope may well hold more than a factor 2 fall (whether your body will is another matter). But if it's at this point you should throw the rope away and never use it again. Also the chances of your experiencing this kind of fall are slim in most circumstances. –  Aug 29 '14 at 10:11

1 Answers1

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A dynamic rope that sustains a fall factor that high should definitely be retired, even if it doesn't show any immediate signs of damage. A dynamic rope is designed to elongate (dynamic elongation of 30-40%) in order to adsorb the shock of such a high-force fall. By doing so it lowers the forces applied to your gear and your body (keeping gear from ripping out and body from serious injury).

Static ropes have essentially zero dynamic elongation ability. A factor 1.77 fall on a static rope would almost certainly rip gear, and cause severe bodily harm either in the catch or the corresponding fall. This is why you should never lead on a static rope.

As far as slings go, it's pretty cheap to replace the sling that caught the fall. You can easily re-sling cams and hexes. In my book it's worth the ease of mind for the next time I'm above that piece of gear.

Brian Eagen
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