DAMAGE FROM STEPPING ON YOUR
ROPE
Several
years ago the German Alpine Club investigated the damage to ropes caused by
stepping on them with boots. They concluded that a rope could not be noticably
damaged by such action. However, they did not do away with German tradition -
the guilty party still has to pay for a beer. Similar tests were performed
using crampons.
Boot
test:
A
90° angel iron was used as the edge and a multifall rope (minimum number of
nine falls) draped over the edge. A person weighing 80 kg stepped on the rope
and rolled three time back and forth with full body weight. This process was
repeated 13 times at a spacing of 1.5 cm. The rope then underwent the UIAA drop
test. The damaged area was placed at the orifice, the carabiner edge of the
test apparatus. In another test the damaged area was placed in the free length
of the rope. In both instances the number of falls held was still nine.
While
one cannot say that stepping on the rope did not cause damage, one can say that
it is negligible.
Crampon
test:
This
test was more difficult to execute. An 80 kg person stepped on the rope with
new crampons, which rested on a stone surface and twisted the foot. While the
rope cross section deformed, the crampon point was not able to penetrate the rope.
In order to be more certain, the crampon point was hammered into the rope until
the point could be felt on the other side. The mantle fibes were then removed
with a hard pointy tool until the tip of the crampon was visible (see figure).
This was again done 13 times at a spacing of 1.5 cm. The test results were the
same as above - the rope still held nine falls.
With
regular crampon use and no obious damage to the mantle, there is no need to
retire a rope, if a climber steps on it with a crampon. Keep in mind that these
tests are done on a rock base. Stepping on a rope in snow can well be ignored.
In almost every instance, the rope rolls sideways and because of the soft base,
there cannot be any penetration.
Some
ice climbers sharpen the points of their crampons like a knife, much sharper
than when they are purchased. The test was repeated with such a crampon point,
which not only had a very sharp point but also sharp edges like a knife. This
point penetrated the rope with the same ease as a pointed, sharp knife. The
result: the rope held only four falls. While this is of some concern, a rope is
still unlikely to be cut over a rock edge after such damage occurs.
Furthermore, the damaged area has to be over such an edge, an unlikely event.
Again it is questionable whether this damage could be reproduced when stepping
on the rope in snow.
The
conclusion is that damage to a rope by stepping on it has been clearly
exaggerated, even with crampons.
1 comment:
Good thing cause I stepped on RMI's rope repeatedly going up Rainier.
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