This past weekend at HamCom in Plano Texas; a representative of Pinkerton
Sales; a manufacturing rep company for "Ultra-Safe", a climbing belt
("fall-arrest") company, gave an excellent demo outside of the convention
hall on their demo-trailer. He would winch up a 220# weight and demo
different situations. The message was that different lanyards ( position or
fall-arrest, whichever) exert dramatic differences in force to the user when
a fall occurs.
As I recall (+/-)and briefly:
1. Six foot conventional lanyard: 2500# (ouch!)
2. Six foot lanyard w/ sewn fold-out layers (shock absorbing): 700# (still
"ouch")
3. Six foot lanyard, now get this, WITH A KNOT IN IT: "0" force; it broke
instantly! (Big ouch!)
At least on two of the ouch's, the user survived.
He demonstrated, basically, two types of climbing harnesses:
1. Conventional, as we know, nylon straps.
2. A nylon harness, but the straps have some very slight stretch to them. I
liked that harness.
He added that any and all harnesses must be tightened "firmly"; not loose
and, of course, not uncomfortably too-tight. Any extreme slack or sloppiness
can be harmful to ones health in the event of a fall.
He also mentioned that always someone should be present while the climber is
working in the tower and have a plan in the event of a fall. He cautioned
that even with the best fall-arrest full body harness, it is very dangerous
to let the climber hang very long in the harness as the force of the leg
straps in the groin area can shut-off blood circulation. It has been fatal.
He demo'd one little gadget, like a reeled-up harness, that you hook ahead
of your climb that catch's you immediately; with no drop at all; much, I
think, as a vehicle safety belt does. Gradual movement around the tower or
climbing does not set it off; but a "instant thrust" (my words) does; again,
much like a vehicle safety belt.
He said that OSHA does not approve climbing gear; but does dis-approve
climbing gear.
As a climber of my own and others towers; it sure got me to thinking. If you
ever have the opportunity to view one of these demonstrations; I highly
recommend it. Especially for those of us that need to be re-educated from
using the old conventional belt-only climbing belt. Sure it worked and
worked good; but it is full of weaknesses.
Mike, K5UO
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