A fall-arrest lanyard *cannot* and *must not* be used as a positioning
lanyard. It has one function only -- to save you from an accidental fall.
The "stretchy" material (the shock absorber) is designed to slowly unravel
during the fall, cushioning the impact on your body. Some fall arrest
lanyards can be used only once -- after the stretchy part unravels, it
cannot be used again and the lanyard must be replaced. I think some fall
arrest lanyards may be reusable (Petzl models come to mind), but personally
if I took a fall I'd have the factory check the lanyard and reload or
replace it. In any event, leaning back on a fall-arrest lanyard, which is
what you would do for positioning, may cause the lanyard to stretch or
unravel. It's a no-no -- never do that.
Your fall-arrest lanyard should be attached to the tower whenever you are at
your work position. Regardless of the device used for positioning (see
below), it should be supplemented with a fall-arrest lanyard. That way, the
fall-arrest lanyard protects you when you unhook to reposition. It also will
protect you if your positioning device fails, or if you accidentally forget
what you are doing and lean back without attaching your positioning device
(don't do that either!)
A Y-configuration fall-arrest lanyard can be used to eliminate
free-climbing, which is the act of climbing without being attached to the
tower (another thing you shouldn't do.) The idea is to keep at least one
hook attached to the tower at all times. That way, if you fall while
repositioning one hook, the other hook will save you. I've found that the
best method for this is to move one hook above your head, move the other
hook to the same rung, then climb until the hooks are at knee or waist
level. Repeat. Seems silly, but if you move just one hook, and keep the
other hook attached to the waist D-ring while climbing, a fall will pull on
the arm of the Y attached to your waist and not on the shaft of the Y
attached to the upper portion of your harness. Depending on the design of
the lanyard, the shock-absorber may not work in this case and during a fall
you can be jerked to a halt by the waist D-ring. Ouch.
Note that while a fall-arrest lanyard can save your life during a fall, you
can be injured nonetheless. Falling six feet or so and being jerked to a
stop can break bones -- even if the shock absorber works. Most people agree
that the safest place to attach a fall-arrest lanyard is your back D-ring. A
stiff yank on the front D-ring could injure your back and/or neck. However,
pictures that come with the Petzl Y-configuration lanyard show it attached
to the front D-ring. While it's a lot easier to attach and move around with
it there, I'd still go with the back D-ring.
Besides, you need the front D-ring for your Lad-Saf cable grab! That is
where the carabiner must be attached. The cable grab is primarily intended
for climbing and descending, but can also be used for limited positioning.
This is a quicker and, I think, safer way to climb than using a
Y-configuration fall-arrest lanyard. It's quicker because you don't have to
constantly hook and unhook. It's safer because you can stop at any time and
lean back for a rest, effectively using the cable grab as a positioning
device. With a Y-configuration fall-arrest lanyard, you would have to thread
your positioning lanyard through the tower before taking a rest. [Since I
don't have a cable-grab, I solve this problem by attaching a carabiner to
the front D-ring, then to a 6-inch piece of man-load-rated strap, then to
another carabiner. This arrangement lets me quickly clip on to the tower
when I need a rest while climbing.]
While you can use the Lad-Saf for positioning, it will likely restrict your
lateral movements too much. I think you will also need an adjustable
positioning lanyard (i.e., a "non-stretchy" one.) Note that regardless of
whether you position with the Lad-Saf or a positioning lanyard, always
attach the fall-arrest lanyard when you stop climbing -- even if you're just
taking a rest.
To sum up, when preparing to climb attach the Y-configuration fall-arrest
lanyard to your back D-ring. Clip the hooks to one of your waist D-rings.
Attach the two hooks of an adjustable positioning lanyard to your other
waist D-ring. Attach the Lad-Saf carabiner to your front D-ring. When you
are ready to climb, clip the carabiner to the Lad-Saf and go up a couple of
steps. Pull down on the Lad-Saf to make sure it stops your movement in that
direction. Lean out from the tower and pump your legs up and down to make
sure the cable is secure and the Lad-Saf is holding all of your weight.
Once you are sure the Lad-Saf is working properly, start climbing. If you
need to rest, put both hooks of the fall-arrest lanyard on tower members as
far above your head as you can reach. Slowly lean back, and make sure the
Lad-Saf is secure and holding your weight before you let go of the tower.
When you reach the work position, immediately attach the fall-arrest
lanyard. It's probably a good idea to separate the ends of the
Y-configuration lanyard as widely as you can so there will be less of a
distance to fall. If you need more lateral movement than permitted by the
Lad-Saf, thread the positioning belt through the tower. Once the positioning
lanyard is place and tested with your weight, unhook the carabiner from the
Lad-Saf. If you climb around on the tower without the Lad-Saf, always keep
at least one hook of the fall-arrest lanyard in place at all times.
Optionally, you could attach a short climbing strap and carabiner to the
Lad-Saf carabiner so you can have a quick-clip positioning setup like mine
for when you move around on the tower without the Lad-Saf. But, once again,
don't rely on the positioning devices alone -- use that fall-arrest lanyard!
I urge you to try all this at the bottom of the tower and make sure you are
completely comfortable with all the equipment and movements before climbing
higher. Tower work can be very fatiguing and it's very easy to forget what
you're doing up there.
73, Dick WC1M
> -----Original Message-----
> From: Alan NV8A (ex. AB2OS) [mailto:nv8a@att.net]
> Sent: Thursday, June 30, 2005 3:34 PM
> To: towertalk reflector
> Subject: [TowerTalk] Climbing safety
>
>
> I've just been reading the messages from Dec. '02 and Jan. '03 and
> picked up a lot of good information, but I still have some questions.
>
> I am planning to put up a 60ft. AN Wireless tower, and I
> intend to get
> the climbing bolts and the safety line option: 3/8" aircraft cable
> running from top to bottom.
>
> I already have the Lad-Saf cable grab that will go with the
> safety line,
> and a full tower-climbing harness (6 D-rings) and a Y-configuration
> fall-arrest (stretchy) lanyard with rebar hook are on their
> way. I also
> have the tower safety book that ARRL sells, but much of that
> seems to be
> directed to people who already have a basic knowledge of how
> to use such
> equipment.
>
> Questions:
>
> Can the Y-configuration fall-arrest lanyard serve as a positioning
> lanyard with the small hook attached to the chest D-ring of
> the harness
> and each of the rebar-hooks attached to a tower leg, or do I need a
> "non-stretchy" lanyard for that? Or does the Lad-Saf/safety line
> combination itself serve as a fall-arrest system rather than a
> positioning device? If the latter, would the Lad-Saf be
> connected to the
> chest D-ring or to the back D-ring? If the Lad-Saf is
> connected to the
> front D-ring, does it need a lanyard there, or would I
> connect the front
> D-ring directly to the carbiner on the Lad-Saf?
>
> If I need a "non-stretchy" lanyard as a positioning device,
> what is an
> appropriate length, taking into account that the tower
> tapers? Do I need
> to look for an adjustable lanyard that I can shorten as I
> move up the tower?
>
> Our club does have a member who works for the cable co., but
> he admits
> that climbing towers is different from climbing poles.
>
> 73
>
> Alan NV8A
>
>
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