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This feature article was snagged from Practices for Belaying a Second: off the harness or
off the anchor? (WARNING AND DISCLAIMER: Complete
knowledge of standard climbing equipment, techniques and
practices is assumed. The following is NOT to be used or
construed as instruction in how to climb or how to belay. Seek
professional, expert instruction before using these
techniques.) It has occurred to me sometimes
when I climb with many of my non-guide buddies, that they seem
puzzled by some of my choices in belaying, practices that have
become habits of mine in guiding. My tendency to belay a
second directly off the anchor rather than off my harness is
one example. I've had to explain and justify my behavior, and
that has led me to ask myself if my guidely thinking is really
applicable to recreational climbing? For instance, when I'm
guiding a multi-pitch climb, I'm almost always leading every
pitch, which means I'm always belaying only a second. For
recreational climbers, this will happen only approximately
half of the time. In the end, I've concluded that the
reasons I do certain things while guiding often apply equally
well in recreational climbing. The job of risk management is
the same in both cases, though it is more evenly shared
between partners in recreational climbing. The environment,
its risks and constraints, is the same in both cases. So it
seems to me it's worth examining some guides' tools and
practices to see if they might be useful in the average
climber's bag of tricks. I offer here an inside view of one
guide's "brain" (I know, that might generate some derogatory
humor in certain circles), for the recreational climbers
inspection, to see if there's anything worth picking in there.
In what follows, I am discussing the pros and cons, the wheres
and whens, of a leader belaying a second directly off the
anchor as opposed to off her harness. Off the harness :
We (the leader) tie in to the
anchor, position ourselves in line between it and the load
(our partner), and belay off our harness with some kind of a
device. In this case, if we are braced to hold the weight of a
fall, we are our partner's first line of defense - we hold her
weight ourselves, and only if we are pulled out of position
does her weight - and ours - come onto the anchor. If we are
not braced, then both our weight and our partner's are
directly transferred to the anchor in case of a fall.
Off the harness, re-directed
: We tie into the anchor, position
ourselves somewhere reasonably close to in-line with the
anchor, clip the rope coming from our partner, into a
carabiner on the anchor, then run it back to our belay device
on our harness. In this case, if our partner falls, we hold
her weight partially ourselves, but the pull is directed
upward into the anchor rather than directly downward toward
her. There is some reduction of what we feel of the load
because of the friction of the re-direct, and the anchor bears
both our partner's weight and our own as well as we are pulled
toward it. Directly off the anchor
: In this case we place the friction
device (never a plate device, stitcht, tuber, ATC or similar,
nor a figure 8 - see below for appropriate choices of devices)
directly on the anchor. If our partner falls her weight is
transferred directly to the anchor and our body holds none of
the weight. When to Belay Off the Anchor
: Why and when would a climber
consider belaying a second directly off the anchor, as opposed
to off her harness? My answer would be, a lot of the time,
maybe even most of the time. This is for several
reasons: A couple of inconveniences with
belaying directly off the anchor: you have to learn a new
belay method (the munter hitch or plaquette device - more
about these below). When you're trading off leads, you need to
switch over to belaying off your harness when your second
becomes the leader of the next pitch (belaying a leader
directly off the anchor is NOT an option). This can usually be
safely done while your partner is re- racking. When Not to Belay Off the
Anchor : There are of course instances when
it's not the best choice to belay directly off the anchor,
such as: How to do it :
Most people aren't much in the
habit of belaying directly off the anchor, so I'll give you
some general principles and specific do's and don'ts
here. Placement, Location and
Construction of the anchor: The anchor needs to have a
single tie-in point from which to hang the load, and where you
will put the friction device. For instance, when you have
several pieces equalized by use of a cordelette, the loop in
the knot you tied in the cordelette in order to create
redundancy, is this single tie-in point. If you have some
other configuration of the anchor, you need to somehow create
a similar simple tie-in point which equalizes the load on the
anchor to this single point. This can be a knot or loop in the
rope, or in some cases a locking carabiner. The tie-in point (the location of
your friction device) should be in a position that makes it
easy for you to operate the belay: to take in and pay out
rope. The ideal location is at about your shoulder to face
height, or higher. If the anchor is any lower than about your
waist, you will have to stoop to work the rope, and it will be
harder to take in and pay out as quickly. If it is too high or
far away from you, there may be too much friction through the
device, making it hard for you to operate the system.
Appropriate Friction
Devices: The devices climbers most often use: plate
devices such as the sticht, ATC or Sheriff; tubular devices,
Figure 8s, are not appropriate for belaying directly off the
anchor. The reason is that with all of these devices, you
brake by changing the direction the rope is running, pulling
the brake end back away from the load to create the friction
to stop the fall. It's too awkward to change the direction of
the rope this way when belaying off the anchor. You would have
to position yourself behind the anchor, to be ready to brake,
but close enough to it to be able to take in and pay out as
well. This is much harder than doing the same thing on your
harness, and constrains both your position and the position of
the anchor too much, defeating one of the greatest advantages
to belaying direct off the anchor, which is freedom of
position and movement. The Munter hitch :
The Munter hitch isn't really a
device at all, but just a hitch in the rope to create
friction. Some tests have shown that it has the greatest
braking power of all devices. In any case, it is more than
adequate for this purpose. It is very easy to hold a fall.
Your brake hand stays in the same position to hold a fall as
to take in and pay out rope - below, or in line with, the
anchor. This is what makes it useful for belaying off the
anchor, as it allows you to stand facing the anchor and pull
the rope through, either right next to the anchor or at some
distance away from, and in line with, the anchor. Once you are
familiar with the Munter, it is extremely fast to set up, no
harder than stuffing a rope through a plate or ATC device,
certainly. Especially with stiff, thick or frozen ropes, it's
often easier. There is really only one problem
with the Munter, and that is that it tends to twist the rope,
especially if you have a great length of rope to run through
it. However, with good technique you can combat this tendency
and correct the problem. The Plaquette :
The plaquette is a device like an
elongated plate, with two long parallel slots. It works by
allowing you to pull the rope through in one direction, but if
weighted in the other direction it automatically locks, a bit
like a ratchet. With a plaquette you can do two things: you
can belay on two strands, each of which can easily be managed
separately (this is really only useful to guides belaying two
seconds simultaneously), and you can let go of the rope
entirely if needed: this is a "hands-free", self-braking
device. While no one wants to encourage doing other things
while belaying, if you did need to divide your attention
momentarily, you could let go with your brake hand for a
second and know that if your partner falls, she is at least
locked off where you last had her. The plaquette can also be used for
lowering and for rappeling (though personally I really like my
ATC for rappeling). It is very good for belaying a second when
using a dual rope technique, such as in ice climbing. It works
reasonably well when the rope is icy, at least as well as the
ATC and other comparable devices. Problems with the plaquette are: it
requires you to learn to use it correctly (not that hard, but
it's different from all the other devices out there); once
your partner has weighted the rope it is very difficult to
give her slack until she can un-weight it; and it's another
piece of gear on your harness to weigh you down. There are two common plaquette type
devices: the Kong Gigi, and the NewAlp Magique. Here are some Do's
and Don'ts for belaying off the anchor... Do's : When belaying directly off the
anchor, your most comfortable and efficient position will be
facing the device, either right next to it or within about 10
feet of it. Any further than that and the friction (both the
Munter and the plaquette devices are rather frictious) will
make it hard for you to keep the rope taut. When your partner arrives at the
stance, be sure as always to either put her on belay from your
harness before taking her off belay from the anchor, or to tie
her in during the transition, so that she is never exposed to
a fall while making the switch. Don'ts : Don't try to belay a leader off the
anchor. You'll find it very difficult to pay out, you will
almost certainly end up with an upward pull on the anchor, and
your partner will get very irritated with you, at the very
best. Load Force
Comparisons... I'll end here by repeating some
not-intuitively-obvious facts about potential load forces on
the anchor using the 3 different belay methods. I
underestimate the load forces somewhat to keep it simple, and
in fact momentum in all cases makes the actual forces rather
greater than described here. However, the relative forces
generated by the different scenarios are fairly accurately
compared. Off the Harness :
If you (the belayer) successfully
brace and keep the load off the anchor, obviously the load
force is zero on the anchor, it all goes on you. To the extent
that you are able to hold some portion of the weight, the load
on the anchor varies. But if you are either not braced at all,
or you get pulled off your stance, then the climber's weight
and your weight both come onto the anchor at once. The
climber's momentum away from the anchor multiplies the force
her weight puts on the anchor somewhat, as does any movement
of your body away from the anchor as you are pulled off your
stance (this is why it's so important for the belayer to be in
line with the anchor and with minimal slack in her tie-in).
So, the force on the anchor is a
minimum of 2 times body weight (once yours and once hers),
possibly more depending on momentum. Off the Harness, Redirected
: In this scenario, it's as if the
belayer is a sort of counter-weight to the climber. When the
climber falls, there are two different sources of force on the
anchor: the climber moving away from the anchor, and the
inertia of the belayer's body resisting movement toward the
anchor, with the re-direct carabiner acting like a sort of
pulley. So there is the potential to generate even slightly
greater forces here than in the case above. Directly off the Anchor
: You can think of this as an almost
perfectly static belay. In this case the only force being
added to that of the falling climber, is the force it takes
the belayer to hold the fall with her hand (with the aid of
the friction device of course). With a plaquette this force is
almost zero, with a Munter not much more. The belayer's body
is not part of the equation. If we assume that it takes a
force equivalent to about .1 to .2 of body weight to hold the
fall through the friction device (source: the American
Mountain Guides Association Advanced Rock Guides Course
Manual), then the force on the anchor begins at 1.1 to 1.2
body weight (again, assuming no momentum on the part of the
climber). My analysis here completely ignores
some real-life factors such as the attentiveness of the
belayer and the effectiveness of her belay. This is a big part
of the reason why I like the plaquette: it safeguards against
a spaced-out belayer very well. If you want to try and incorporate
some of these devices and techniques into your climbing, find
expert instruction by someone who uses them often. For a
listing of guides, visit the our guides directory, and for
certified guides visit the American Mountain Guides
Association website at http://www.amga.com/
Happy Climbing! - Kathy More suggestions? Different views?
E-mail
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