UKC

Worn Fixed Gear Can Cut Your Rope

© UKC News
In a recent study by Mammut, tests have show that some fixed carabiners (often found on steep sport crags) can be worn in to such a shape as to cut through your climbing rope in a fall as short as 2.7 metres.

The photo below shows a carabiner taken from a crag and tested by Mammut:

Carabiner - Mammut

Whilst it may come as no surprise to many experienced climbers that old fixed equipment might not be very strong, a cut rope is such a potentially dangerous occurrence that we thought it worth highlighting this report.

Here is the full statement from Mammut:

Mammut is urgently calling for the immediate discontinuation of use and removal of permanently installed quick draws and carabiners in climbing areas. Irrespective of the manufacturer of such equipment, repeated wear can result in the formation of sharp edges capable of damaging or completely severing ropes, even in relatively small falls. Investigations by Mammut have shown that this known problem is actually far more dramatic than previously assumed and represents a very high risk for climbers.  

In recent years, it has become increasingly common to install quick draws on overhanging routes in climbing areas. On the one hand, this is intended to make it easier to clip the rope and, on the other hand, to prevent the sometimes laborious removal of the quick draws. 

Depending on their position, as a result of friction from climbing ropes when lowering climbers, these quick draws can be worn to a blunt angle resulting in the formation of very sharp edges (see photo above). The following positions are particularly affected: 

• the first belay point (where the belayer stands away from the wall when lowering)

• belay points under a roof/overhang 

• off line belay points 

Wear is increased by the presence of dirt or sand on the rope. Extremely sharp edges form on carabiners which almost never bear the load of a fall and are rarely used as a turning point. This means that they are never "deburred" (worn to a rounded shape) and razor-sharp edges can develop. Carabiners with a T-profile tend to be more prone to the formation of sharp edges in comparison with round profiles. 

In tests in the Mammut standard fall facility on the carabiner shown above, it was found that a 9.5 mm rope with fall mass of 80 kg severed at a fall height of just 2.7 meters/fall factor of 1.0.  The carabiner used had an extremely sharp edge. Previous investigations have also shown that, in practice, friction in the safety chain can result in a fall factor that is significantly higher than the calculated value. In combination with a very sharp carabiner, even very small falls with a fall height of less than a meter can be critical. Several cases of cut ropes without grave consequences are known. Presently this is being researched as a possible reason for a fatal climbing accident in Switzerland. 

Graph Mammut

Mammut also examined the effect of the rope diameter on these sharp edges. A clear connection emerged, as shown in the graph above: in all cases, a thicker rope offers a higher safety margin in relation to sharp edges. However, even with a 10 mm rope the values are critical and life-threatening. Twin and half ropes (both ropes clipped) offer the highest safety margins. No significant differences were observed between the values for used ropes (light furring on the sheath, no damage) and new ropes.

Sharp edges can also develop on carabiners at the anchor point, however in this case the rope runs over the carabiner at an acute angle, resulting in a rounded wearing effect and the edges formed are less extreme. However, these carabiners can be critical if the remaining strength of the equipment is not sufficient to support the load. 

Climbing gyms generally use steel carabiners which wear less quickly and the fixed equipment is checked regularly. However, Mammut recommends paying close attention in this situation as well. Do not use any worn carabiners and report them immediately to the climbing gym operator. 

Fixed equipment on outdoor climbing routes is not usually maintained or checked. In general, care is required due to deterioration of slings, corrosion, etc. and it is best to avoid using the equipment.


This post has been read 11,246 times

Return to Latest News


14 Nov, 2012
//www.blackdiamondequipment.com/en-us/journal/climb//qc-lab-dangers-of-rope-worn-carabiners
14 Nov, 2012
"Whilst it may come as no surprise to many experienced climbers that old fixed equipment might not be very strong" I was under the impression tests showed worn biners with rope groves were a lot stronger than expected.
14 Nov, 2012
yeah I'd seen this news item before somewhere else myself.
14 Nov, 2012
Not only dangerous to climbers but also can cause access problems. Good to see last year many insitu or perma-draws removed from Raven Tor....what is the current situation at Kilnsey? What is the BMCs position on this? And still other crags, like Roadside Crag in Kentucky, were closed due in part to the landowners’ growing concern over the presence of permadraws. http://www.opengate.org/access-fund-blog/2012/04/permadraws-access-issue-or-not.html The debate on fixed/perma gear at sport-climbing areas is coming to a head now that dozens of crags across the country have high concentrations—sometimes hundereds—of “fixed” or “perma” draws—terms that are used to describe everything from chains and steel-cabled quickdraws with steel carabiners, to regular quickdraws with aluminum carabiners—that have been left on a route, simply donated or abandoned. http://www.rockandice.com/news/1902-featured-debate-permadraws 22 September, Mario Luginbühl and a friend went climbing at Magletsch, in the St.Gallen canton, Switzerland. Mario was trying to work out a sequence and took a controlled fall. This proved fatal as the fixed quickdraw had been worn sharp through extensive use and cut the rope right off, resulting in Mario falling 25 meters to his death. http://www.ukclimbing.com/news/item.php?id=67521
14 Nov, 2012
It can be but in this case the old fixed equipment doesn't break the rope does.
More Comments
Loading Notifications...
Facebook Twitter Copy Email