At 12:58 PM 6/14/2006, Dick Green WC1M wrote:
>Excellent question. I've wondered the same thing. There have been a number
>of posts on this reflector indicating that serious injury can occur if you
>fall with a fall-arrest lanyard attached to the front D-ring, and that the
>correct point of attachment is the back D-ring. Presumably, being yanked
>hard and suspended by the front D-ring can cause back injury.
There's also a difference between "likely to happen" and "could happen".
Back in my younger and more foolish days, I used to rock climb using a
"swami belt" as the sole means of attachment to the rope. This is a 20ft
length of 1" tubular webbing wrapped around your waist and tied, and was
then (early 70s), state-of-the-art, compared to just tying the rope around
you. I took more than one fall of more than a couple feet on such a rig
and managed to escape mostly unscathed. We won't even talk about what a
long rappel might feel like. In the typical climbing fall, though, you have
a fair number of feet of moderately stretchy rope between you and the
belayer. This was about the time when people actually started looking at
the dynamics of falling and coming up with standardized test fixtures for
such falls, and I notice that fairly quickly, real harnesses came to be
pretty standard. Doesn't mean I'd even contemplate such a thing
today. Notwithstanding some fatalities of the era, directly related to
severe leader falls and/or hanging from the rope around your waist too
long, it does show that it isn't certain death. Just "more likely death".
Better fall protection might change it from 1 death:100 falls with a swami
belt to 1 death:10,000 falls with a harness. I suspect that better fall
protection is part of why there are 5.14 climbs at all (since the scale
used to max out at 5.9/5.10).. With 70s vintage fall protection, on a
really hard/exposed climb, a fall might mean death, regardless of whether
you had a rope or not: meaning you only get once chance on the
climb. Today, you could fall off a bunch of times, and live to tell the tale.
>It would be nice to have references to studies or other empirical data
>supporting this claim. If such evidence really exists, then I find it
>irresponsible that Petzl, a company that appears to have considerable
>expertise in this area, recommends front attachment in brochures for
>harnesses that have both front and back D-rings. Shouldn't OSHA be on their
>case? OTOH, if people are posting bogus claims about safety procedures
>simply because the believe them, then that's irresponsible, too. Looks like
>at least one party is irresponsible.
In rock climbing, at least, one generally attaches the rope in the
front. On the other hand, it's also getting in the way all the
time. Maybe the "attach to the back" recommendation is to keep your
workspace clear? or, maybe, one way does have better statistical outcomes
than the other, but it might be occupation dependent. Certain types of
falls are more common than others, depending on what you're doing (window
washing is different than electricians on a movie set is different than a
steeplejack, etc.) Any time you're talking about occupational issues, one
also has to look a the evaluation metric: Is it "lack of death" or "lack
of lost work days and worker's comp claims". Recreational climbers might
choose the first, an employer might choose the latter.
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