----- Original Message -----
From: "Jim Lux" <jimlux@earthlink.net>
> However, I think your point is valid when comparing rock climbing gear
> with
> tower climbing. They're both climbing, but not really the same. On a
> tower, if you fall, it's MUCH more likely to be a free fall to the end of
> the rope. So, while fall frequency might be higher in rock climbing (in a
> falls/hour sense), average fall severity is much lower.
>
I don't understand all the fuss about using man rated climbing
ropes and such for tower climbing. How many people climb
towers where they are counting on a long slack ropes for fall
arrest? I use pair of gorilla hooks attached to short heavy rope
lanyards. At most, there is 2 or 3 feet of slack in the lanyards.
>>6. While I can't confirm this, it's safe to assume that the guy hardware
>>(cable, turnbuckles, shackles, etc.) is probably cheap stuff from the
>>hardware
>>store instead of load rated, American (therefore, if it fails, traceable
>>back
>>to the ore mine) hardware like from The Crosby Group. Why do I assume
>>this? He
>>chose to "save money" rather than "do it right", so I can't imagine that
>>he
>>didn't pinch pennies here.
Jason, I have been up and down more times than I can count
two towers which N5OT helped engineer and install. All the
guy clips, shackles, and turnbuckles on those installation are
quality forged hardware. You automatically assumed that
because Mark built some highly overengineered homebrew
bases for his towers to save a few bucks (no false economy,
no increased risk of system failure) that he would also buy
cheap off-brand guy hardware (very false economy,
considerable increased risk of system failure).
>
>>Anyone who makes that kind of decision, good intentioned or not, is
>>deciding to bypass all of the engineering specs of the manufacturer and
>>certified engineers. That's a get out of jail free card to Rohn for any
>>failure and a quite possibly get INTO jail card for him.
>
You would have to have a pretty stupid jury to conclude that
substituting those homebrew bases using 3/8" thick steel (probably
3 to 4 times heavier than stock Rohn product) rose to the level of
criminal negligence. The only way those towers are going to fail is
in a severe weather situation. What is the likelihood that somebody
is going to be standing under those towers during a thunderstorm
or a tornado on a farm in rural Oklahoma? And if the towers did
fail and somebody was killed or injured, you would have to prove
that the homemade bases precipated a premature failure that would
not have happened had the installations used the Rohn bases. I
don't see how any reasonably intelligent person could come to that
conclusion with respect to the homemade bases. If he was using
polypropylene rope to guy the towers, you would probably have a
good case.
>>So, say goodbye to everything that you own that isn't homesteaded,
>>anything more than one car, and half of all of your future earnings.
>>That's IF you are lucky enough to still be a free man because you were not
>>found CRIMINALLY NEGLIGENT.
>
>>Of course, so is using another tower as a guy point.
>
> You're making an assertion that using N5OT's use of a tower as a guy point
> is criminally negligent. You make this assertion without any real
> knowledge of any analysis that has been done, and without yourself being
> qualified to make the assertion. I know you feel strongly, Jason, but you
> are basically accusing N5OT of a crime, and that's a pretty strong
> statement (as in probably defamatory and libelous).
>
I agree, Jim. Although I think Mark's decision to use that common
guy point was a bad decision (I think even Mark agrees), I don't
think by any stretch it could be considered criminally negligent.
Assuming that the hardware at the common guy point is up to the
job and the installation was done using good engineering practice then
the installation should be fine under all but the most extreme conditions.
The bad part about the common guy point is that it represents a
potential single point failure whereby the whole installation could be
lost if the common guy point happens to fail. This would only be
likely to happen in a extreme situation (tornado, microburst, etc), but
in an extreme situation all bets are off anyway. Even if Mark had used
isolated redundant guying for each tower, that doesn't guarantee that
his towers would survive an extreme weather scenario. You could
reasonably argue that using isolated and redundant guy points would
add some incremental survivability to the system, but even with the
isolated and redundant guy points you still can't guarantee that the
system will survive no matter what. If that were the criteria for safe
installations nobody would every be able to build anything (and we
would have to cut down all the trees in the world while we were at
it too).
Did Mark add some incremental risk of total system failure when
opted for the common elevated guy point - yes, I think you can
make that argument. Is his installation inherently unsafe - I hardly
think so.
It is good to be cautious and even a little paranoid when working
with towers, but common sense should prevail.
73, Mike W4EF........................................
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