For some time I've been considering a safety cable system for my 110' Rohn
45 tower. I currently use a fall-arrest Y-lanyard with large gorilla hooks.
While reasonably safe, the lanyard system requires much more time and energy
to climb up and down than a safety cable system. That time and energy are
very important, especially when spending long hours on the tower. More than
once I've been fatigued when climbing down, and the constant
clipping/unclipping take a lot out of me. I've also got the beginnings of
osteo arthritis, and sometimes my hands get very stiff after several hours
of working on the tower. They also tend to swell and cramp. The added strain
of clipping and unclipping makes this much worse, reducing my ability to
grip the tower when decending. It's a real safety consideration. As best I
can, I minimize time on the tower to compensate.
Further, as Dave points out, fall-arrest lanyards can let you fall as much
as 6 feet before you stop. While you won't be stopped with a dangerous yank,
like you would with a standard lanyard, it's still going to hurt. Also, much
has been written here about the dangers of being suspended in a fall-arrest
lanyard after a debilitating fall. That said, I make it a practice to attach
my fall-arrest lanyards as high above my head as I can reach in order to
minimize any drop. Of course, this may not be feasible when moving around
the tower, but that problem isn't solved by the cable system either, and
short lanyards are worse.
At first I rejected the idea of Dave's short, non-arrest lanyards. I'm not
convinced that a fall of even a couple of feet without a shock absorber
would not result in injury. Also, I would find short Y-lanyards too
constricting to movement and likely I'd have to unclip at times to move
around the tower. But after further reflection, I'm wodering if short
Y-lanyards with fall-arrest protection might actually be better than what I
have. I saw just such a model, made by Black Diamond for rock climbing, at
the Outdoor Retailer show. The leads are much significantly shorter than the
ones I have, but feature fall-arrest protection. I don't think this would be
a problem when climbing -- I think it just means I wouldn't have to clip the
lanyards as far above my head. They may, however, restrict movement around
the tower and might not work when climbing over my three TIC rings (see
below.)
The main problem with using a cable system on my tower is the three TIC
rings. I'm pretty sure the Rohn cable system sticks out too far to fit
inside the TIC rings. Not sure about the Tuf-Tug system. Even if it would
fit, there may not be enough clearance to pull the cable out from the tower
without hitting a ring when nearing a TIC ring or pulling on the cable to
test just after clipping on (standard procedure, as I understand it.) I'm
willing to consider three separate runs, though that would probably be very
expensive. Given that I'll have to unclip to climb around the rings, it's
not a big deal to use three separate runs instead of one, except from the
cost perspective.
As has been said, a cable system does not eliminate the need for a
fall-arrest lanyard. If I put up a cable system, I'll keep my Y-lanyard
because it's necessary for climbing around the TIC rings and is critical
after reaching the work position.
73, Dick WC1M
-----Original Message-----
From: Jim Thomson [mailto:jim.thom@telus.net]
Sent: Saturday, August 14, 2010 3:33 AM
To: towertalk@contesting.com
Subject: [TowerTalk] Fall Harness-My Choice
Date: Fri, 13 Aug 2010 17:38:54 -0700
From: David Gilbert <xdavid@cis-broadband.com>
Subject: Re: [TowerTalk] Fall Harness-My Choice
I have an AN Wireless HD-70 freestanding tower with the foot pegs ...
slippery enough to require caution when wet, but not treacherous. I
climb with a full body harness with two relatively short safety straps,
neither of which are fall arrest lanyards. Each safety strap has a
self-locking gorilla hook on the end (required because of the large
steel cross braces on the tower), and one or the other hook is ALWAYS
attached to a cross brace as I climb. I even have a third strap and
gorilla hook coming from a separate belt around my waist that I affix to
the tower while I am working.
The hooks I use are made from a high strength aluminum alloy ... very
light and extremely strong. *http://tinyurl.com/25dns9a*
In general, I'm afraid of heights but don't feel ill at ease on the
tower with this system. If I die falling from it, it will be because I
was stupid.
## That method will work... but makes foe slow climbing up/down the
tower. Plus you are continually having to hook/unhook the L/R
gorilla hooks... which means you have one hand off the pegs 99%
of the time.
## That 3/8" safety winch cable scheme that both Trylon and AN Wireless
have for those types of towers works superb. The safety cable sits a few
inch's
from the tower leg... in between the foot pegs. You hook onto the
cable.. and now you
never have your hands off the foot pegs..while climing UP. When coming
down, you have to
hit the sprinloaded rls... and slide the safety device /grabber down a
couple of feet.. then
climb down some more... slide it down again etc.
## IF you slipped and fell, the grabber will lock onto the 3/8" cable, and
ur going no where. IMO,
you are much safer this way, not having to constantly hook/unhook
alternating L/R gorilla hooks.
However, if gorilla hooks used, TWO of them, like you have, is much safer
than just one. At least
with 2 of em, you are assured that you ar tethered to the tower at all times
by at least one hook.
## all the safety cable amounts to is 3/8" winch cable with
single/double nicropress crimps at top
end... and a spring loaded tensioning device at the bottom end... to keep
the cable taut. Nobody
ever broke 3/8" winch/aircraft cable, when falling 6".. b4 it grabs.
Later... Jim VE7RF
73,
Dave AB7E
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