If you were going to fall from a tree, what would be
high on the list of things you would rather not land on?
Most people will have iron railings well up on that list,
but for one climber last year that was precisely what
he plummeted 52 feet on to, picking up two puncture
wounds in his back, one inch away from his spine. He
was more than a little lucky, discounting the falling in
the first place, as his harness absorbed the worst of
his fall and stopped the spikes from ripping deeper.
Remarkably, he is back at work and climbing again.
Now that I am sure I have your attention, you probably
have a few questions to ask: “How did he fall?” “What, if
anything, did he do wrong?” “What broke?” Before I tell
you, remember the sick feeling in your stomach looking
at the photo of the harness on the fence and learn from
someone else’s lucky escape.
He was foot locking into the tree using the double
rope technique (DRT) with mechanical ascenders. When
he reached the top, about three feet under his anchor
point, with the ropes pulled together with an alpine
butterfly, he reached out to his side about an arm’s length
to take hold of a branch to pull himself in to stem and
lanyard in. One of the ropes in his ascenders popped out
and he fell. Turning, trying in vain to grab the ropes in
front of him, he saw the ground and railings come towards
him. He could not quite believe what was happening; he
thought for sure he was going die, then bang! A sudden
stop. He hit the railings, feeling them punch in to his body,
he was winded, conscious but alive.
How could this happen? Good question. Well it
happened and the companies that make such devices
are aware of the potential for it to happen because
clearly marked on all devices is the maximum and (more
importantly) the minimum diameter of the rope that they
can be used with. Also stated in the instructions are the
directions and limitation of use, they are for one directional
use, to be loaded only from below the device, they are
not designed for lateral movement. It has been known
for a while that this could happen and climbers have had
moments where it nearly did.
The findings of the HSE investigation held no one
at fault. All actions had been following the current best
practice, so what should we do to stop this until someone
builds us a new device for tree access alone?
What now? A better question. First, the “Guide to
Good Climbing Practice” is currently under review prior
to a second edition and DRT is one of the areas being
worked on. In the meantime, if you are using such
devices, what you must do is put in a fail to safety, a back
up or safeguard of some sort that will hold you if one of
the cams should fail or, as in the case above, the rope
should work free of the device altogether.
There are many and various ways of backing up
the DRT system utilising ascenders, but what needs
to be made clear is that just adding a prussic loop on
both lines (as you would if you were foot locking with
a prussic) will not be backed up. This is because if
one side of the ascenders fails, the ropes will move in
opposite directions and the prussic will not grip. What
you must do is treat double ascenders as two separate
ascenders that just happen to be joined together. Each
side must be backed up.
To that end, a friction hitch, prussic lets say for
simplicity, is installed one above each cam, one on each
line and then connected to the karabiner attaching the
ascenders to your strop (Fig I) or linked into the system
on your harness. You will need to take care when
choosing your karabiner, so as not to overcrowd or load
it incorrectly. Another method would be to use a second
cam on each line; doing this will isolate each line. Walk a
second set of ascenders up the ropes to the top (Fig II),
set the correct distance away from your anchored limb
to allow for the spread ratio, or up to a butterfly knot and
bring the ropes together under the anchor point.
There are many other ways to back up DRT utilising
ascenders but I have insufficient space to mention them
all here. If you want to find more ways to back up your
system, check out arbtalk.co.uk or treebuzz.com, come
and have a chat at one of the many events this year at the
tree climbers’ forum or just chat to some of the climbers
competing or judging at a TCC event. Above all climb safe
and keep your system simple, so you and your groundy
can fully understand what is going on. If you are not sure,
go back to a simple prussic loop for foot locking. Think
about reaching out a little and get online, or book some
update training.
Alexander Laver
Tree Logic
ISA UK&I TCC Chairman