>From: ve5ra at sasktel.net
>.. but the simple steel cable running up the side of the
tower, with the locking device, will ensure you dont fall ... when going up
or down the tower.
## Once you arrive at the desired level of the tower, you hook in with both
lanyards. That’s
about as simple and safe as it gets. The steel cable running up the side of
the tower will not impede
climbing the tower, cost very little to install. You will never die from
falling off the tower... cuz you are
tied onto the tower at all times. .375 inch EHS cable is dirt cheap.... you
only require enough to
>span the height of the tower. IE: 50-200 feet.>>>
First of all, how did you install the steel cable on the side of the tower
without climbing it the first time without the protection?
I can appreciate the fall arrest cable if you frequently climb the tower. I
use my tower as a quarter wave vertical for 160, and to hold up an open-wire
line fed dipole at the 119' level. The antenna requires little maintenance, so
I very seldom have a reason to climb the tower. Until recently, I hadn't
climbed in over fifteen years. Since all hardware can be expected to eventually
rust or corrode, I don't know if I would feel comfortable betting my life on
the unknown condition of a steel cable and connecting hardware that I hadn't
inspected for more than a decade.
I put up my 127' of Rohn 25 single-handedly in 1981, using only a Korean War
era US Army Signal Corps climbing belt made of nylon webbing sandwiched between
two layers of leather. The thing was heavy and bulky but I felt comfortable
using it, with the addition of a second light weight lanyard to enable me to
retain 100% tie-off while crossing the guying points. Before my most recent
climb I threw the thing away. The leather was visibly deteriorating and I knew
better safety equipment was available. I purchased a near top-of-the-line
climbing harness and a couple of positioning lanyards, along with a set of
gorilla hooks.
I always climb my tower with one positioning lanyard strapped around the tower
at all times, just as I did with the old Signal Corps belt. I don't find it a
problem to slip the lanyard up the tower with me as I climb, and whenever I
cross a guying point I attach the second lanyard above the guy bracket before
disconnecting the first one below, just as I did with the old belt. I used the
gorilla hooks with my recent climb, but I think I'll leave them on the ground
next time. Constantly hooking and un-hooking those things as you go while
climbing up and down is very fatiguing and takes at least twice as long as
climbing with a simple lanyard. Even with the proper fall arrest lanyard
attached, dropping six feet while tethered to a tower could cause serious
injury. It would certainly be traumatic, and likely end the project for that
day. The fall arrest lanyard is a one-use item so it would have to be replaced.
Most worrisome of all, particularly using a climbing harness with gorilla hooks
and fall arrest lanyards, is a little-known phenomenon called suspension
trauma. Suspension trauma is caused by "orthostatic intolerance", which can
occur any time a person stands quietly for prolonged periods. It is most
commonly encountered in military parades where soldiers stand at attention for
extended periods. This may be prevented by keeping the knees slightly bent so
the leg muscles are engaged in maintaining posture. When the legs remain
immobile with the person in an upright posture, gravity pulls blood into the
lower legs, which have a very large storage capacity. Enough blood eventually
accumulates so that return flow to the heart is reduced. If the blood supply is
restricted enough, the worker or soldier will faint, slumping to the ground
where the legs, heart and brain are on the same level, allowing sufficient
blood to return to the heart. Suspended in a harness, the person can’t fall
into a horizontal posture, so the brain’s blood supply falls below the critical
level. The harness keeps the worker in an upright position, resulting in loss
of consciousness and eventually death. A worker suspended in an upright
position with legs dangling in a harness of any type is subject to suspension
trauma. See
http://www.fs.fed.us/treeclimbing/safety/suspension-trauma.pdf
With the positioning lanyard strapped to the climber and around the tower, the
worst thing that could happen would be for the climber to loose his footing. He
might slip a few feet but the lanyard would prevent a free fall, and keep the
climber tied close enough to the tower to regain his footing and likely safely
descend the tower.
The greatest problem I have with climbing Rohn 25 is that with most available
footwear, the tower rungs are not wide enough to allow one to stand securely
and comfortably with both feet on the same rung. Larger towers, like the Rohn
45, are much more climber friendly.
Nylon webbing type lanyards have a tendency to fray when on a tower that has
significant surface rust. After I have climbed a time or two with a new
lanyard, I inspect it for signs of fraying, and wrap those areas with grey duct
tape. This seems to keep the nylon fabric intact if the tape is replaced after
each climb.
Don k4kyv
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