Thanks for re-posting this important information, Jim. I've been putting
together a climbing system based on these principals, but with a couple of
variations made possible by the harness I have. I bought a new Gemtor Model
2015 full-body harness (see http://www.gemtor.com/harnesses.htm, bottom of
page) from another ham who didn't like the fit and had never used it. The
picture doesn't show the suspension rings for the seat sling, which are in
the front.
First time I used the harness, the suspension rings were in the way, so I
clipped them to the front D-ring with a carabineer. This seemed OK since the
front D-ring on this harness is intended for positioning only, not
fall-arrest, and I wasn't using it for positioning. I attached a 6-foot
fall-arrest lanyard to the rear D-ring with a locking carabineer and
attached an adjustable 1" webbed lanyard to the hip D-rings on the belt. The
fall arrest lanyard is the folded shock-absorber type that extends under the
weight of a fall to cushion the impact. I put the positioning lanyard around
the Rohn 45 tower, attached the fall-arrest lanyard to a tower rung as far
above my head as possible, and dragged the positioning belt with me as I
climbed. When moving the fall-arrest lanyard from rung to rung, I leaned
back against the positioning belt to minimize the chance of slipping off the
rung on which I was standing. When I reached an obstruction, I made sure the
fall-arrest lanyard was securely attached, unhooked the positioning lanyard,
re-hooked the positioning lanyard above the obstruction, and continued
climbing.
There were several problems with this setup. First and foremost, the
positioning lanyard is not supposed to be used for fall protection, which is
the purpose it served while I moved the fall-arrest lanyard. Second, it was
very difficult to unhook and re-hook the positioning lanyard when I came to
an obstruction. I would have to hold on to the tower with one hand ("three
points of contact"), unhook the lanyard from my belt, pass the hook to the
hand that was holding on to the tower, grab the tower with the other hand,
climb a rung or two, pass the positioning lanyard over the obstruction, grab
it with the other hand, transfer my grip on the tower to the other hand, and
rehook the positioning lanyard onto my belt. This works pretty well on Rohn
25, but my short arms can barely make it around Rohn 45 and it turned out to
be quite tricky. This was a 100' tower with three sets of guys, a tic-ring
and several sidearms, so progress was slow and scary. You might wonder why I
didn't lean back against the fall-arrest lanyard, as recommended in the
piece Jim re-posted. Well, my understanding is that you shouldn't do that
with a fall-arrest lanyard because it could compromise the shock absorbing
system. It's not designed for positioning, only for fall-arrest. Does anyone
dispute that? Finally, the gorilla hook on the end of both my fall-arrest
lanyard and positioning lanyard are the small kind with safety locks, which
made hooking and unhooking a bit more difficult.
(Note -- I have not yet tried to climb a tower with the configuration that
follows):
To improve the situation, I replaced the fall-arrest lanyard with twin
fall-arrest lanyards in a Y-shaped configuration. I selected the Petzl
Absorbica-Y MGO (http://www.petzl.com/petzl/Produit?Produit=329&Conseil=).
Similar to cowtails, this device will let me keep a fall arrest-lanyard
attached to the tower at all times. The tricky part is using the Y-lanyard
when it is attached to the rear D-ring. It doesn't appear to be feasible or
safe to climb with one lanyard coming over each shoulder. My experiments on
the ground indicate that it's best to put both lanyards over one shoulder.
Also, regardless of whether the lanyard is fixed to the front or rear
D-ring, you can't have one hook on the tower and the other hook on one of
your belt D-rings. If you do that and fall, the shock absorber is defeated
-- the two lanyards are pulled in opposite directions and catch before the
shock absorber comes into play. This means you have to let one hook dangle
while climbing up to the other one (attach the free hook, unhook the other
one and let it drop and dangle.) Alternatively, you could just clip both
hooks to the tower when you climb. When the hooks get to about waist level,
you unhook one, hook it as high as you can reach, then repeat with the other
hook. Either way, one hook is always attached to the tower. I'm not sure
which way will be best. Any thoughts?
>From my experiments and the drawings in Petzl's literature, it appears that
the Y-lanyard probably works better with a front D-ring because the lanyards
are in front of you, making it easier to climb. Again, the front D-ring on
my harness is not designed for fall arrest -- in a fall, the chest and
shoulders straps could pull up to the chin since the D-ring is not attached
to the front of the belt. In any case, I think there would be a chance of
back injury if the front D-ring on my harness was used for fall-arrest. It
looks to me like it is perfectly safe to use the rear D-ring with the
Absorbica-Y MGO. Anyone think differently?
I made one other improvement. Since I still think it would be a bad idea to
lean against the Y-lanyard or use it for positioning, I decided to add a
small positioning aid to my harness. I clipped a locking carabineer to the
two suspension rings on my seat sling, put a 6" Petzl climbing strap on the
carabineer, and put another self-locking carabineer at the other end of the
climbing strap. The strap is designed for rock climbing. It's made of heavy
cloth webbing and has a 22 kilo-newton breaking strength. This arrangement
lets me quickly clip on to the tower and lean back for a rest without having
to throw the positioning belt around the tower or thread it through the
rungs (one-handed.) It also frees up both hands when I I'm ready to put the
belt around the tower or through the rungs at the work level. Since the
suspension rings are rated for positioning, and the strap and carabiners are
rated for man load, I believe this is a safe arrangement. Of course, both of
the Y-lanyards will be attached to the tower when I'm using this quick
positioning device. Can anybody think of a reason why this wouldn't be safe?
Comments on my new system before I use it?
73, Dick WC1M
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