technical rescue

8/8/2019 Technical Rescue

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TECHNICAL RESCUE EQUIPMENT AND

TECHNIQUES

This chapter discusses the equipment and techniques used in technical rescues.

Equipment

Belay and Lowering DevicesStretcher Basics

Anchor Systems

Lowering and Raising

Traversing Systems (Tyrolean Traverse)

INTRODUCTION

It has been said that there are many ways to "skin a cat." This is particularly true fortechnical rescue rigging because of its complex nature and many diverse techniques. This

chapter doesn't attempt to describe what is "best" or to describe the "art" completely; itdoes describe in detail the techniques that CLMRG uses to perform technical rescues. We

will modify this chapter as new equipment and data become available. We highly

recommend References 4-1 through 4-11 for additional study.In this chapter, we outline safe and adequate procedures for technical rescues. We have

been practicing and performing technical rescues since 1958, and many things have

evolved over the years. We have incorporated new equipment and new techniques as we

became convinced of their safety and utility. This chapter describes the equipment andtechniques that we are using currently. We prefer to use commonly carried climbing gear

as much as possible rather than special purpose equipment. We have to carry our gear tothe rescue site, and the lighter our load, the better we can perform.This chapter, along with "hut" nights and stretcher practices, gives you most of the rescue

skills needed for high-angle technical rescues, but they don't prepare you for the

"exposure." All members of a rescue team who work on the rock must be comfortablewith this high-angle "exposed" environment. The average person doesn't have this

comfort level unless he is an active rock climber.

The safety of everyone involved is paramount! The "on-the-hill" Operation Leader (OL)

must be in charge and is responsible for assigning tasks and checking that everything isdone safely and correctly. The OL must know all the technical rescue skills and the

capabilities of all the participants. Assigning specific tasks requires that the OL be fully

aware of the strengths and weaknesses of each member.WARNING - - Even when properly performed, loss of life or injuries may result to you

or the persons you are working with.
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EQUIPMENTROPES

Rock climbers and mountaineers use a dynamic rope. This rope is designed to be elasticto reduce the shock on the climber and anchor system if a fall occurs. For general

climbing, the norm in the United States is a single dynamic rope of 9.8, 10, 10.5, or 11millimeters (mm) in diameter. Smaller diameter ropes (8.5 to 9 mm) are used with two-rope techniques and for special applications where high-impact leader falls are not

expected.

Rescue workers use a static (low-stretch) rope for lowering and raising. This ropeminimizes elongation when it's first loaded and additional stretch (creep) as the load

remains on it. The mountain rescue community uses 7/16-inch or 11-mm diameter ropes

for both the main line and the belay line. Table 4-1 gives typical specifications for the

ropes we use.

Table 4-1 Typical Specifications for Ropes

Description Tensile Strength Elongation(%)

Impact Force(kN)

11-mm dynamic (Blue

Water)12 UIAA falls 6 8.1

11-mm static (Blue

Water)

6500 lbf

(29kN)1.6 Much higher

WEBBING

Tubular webbing is available in a variety of widths and constructions. The most popular

variety is 1-inch supertape, which we use to tie in the victim to the stretcher. A morerecent development is a combination of nylon and Spectra ("the strongest fiber ever

made"). Spectra comes in only one width (9/16 inch) but is almost as strong as the 1-inch

supertape and equal to its abrasion resistance. The smaller width is a distinct advantagewhen the webbing must be clipped through a carabiner because it's less likely to side load

(load the gate side of) the carabiner.

Runners are loops made from webbing. The loop can be made by tying a knot or bysewing. We use Titan sewn runners made from Spectra, which are significantly (about

1000 lb.) stronger than tied runners. The recommended knot for tying runners is the

grapevine knot rather than the water knot because the water knot can "walk" and untieitself. Table 4-2 gives typical specifications for the webbing that we use.

Table 4-2. Typical Specifications for Webbing and Runners

Description Tensile Strength

1-inch tubular webbing (Blue WaterClimb-Spec)

4200 lbf.

9/16-inch Titan runners (Blue Water) 6600 lbf.


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CARABINERS

A locking carabiner is preferred for rescue applications. The locking carabiner used for

climbing is adequate for rescue applications. The typical strength rating for a lockingcarabiner is 22 kN or 4950 lbf. Two aluminum carabiners with gates opposite and

opposed can also be used.

Do not use carabiners unless they are essential to the system being constructed. Forexample, tie the belay line directly to the stretcher rigging because the carabiner is

unnecessary. Remember never to tie or loop webbing around the cable of a wired nut or

other wired piece. And girth hitching runners reduces their strength just as tying a knotwould.

ANCHORING DEVICES

We rely primarily on chocks, nuts, and active camming devices to form the required

anchors. Placing these devices requires that rescuers are very experienced in using themcorrectly. Bolts can be placed if chocks or cams cannot be used. Don't overlook the use of

natural anchors if they exist (e.g., large rocks or trees).

Bolts that are already in place are difficult to evaluate and should be examined very

carefully before use. Quarter-inch bolts should be considered as marginal at best, andtheir use is discouraged. Pitons that are already in place are also difficult to evaluate, and

caution is advised.Table 4-3 provides strength specifications in pounds of force (lbf) for a variety of

anchoring devices as a function of their size. Any device with a strength of under 2000

lbf should not be used for high angle rescue work. The smaller devices do not meet this

criterion and are not listed.

Table 4-3. Typical Specifications for Anchoring Devices

Devices Size Strength (lbf)

Camming Devices

Aliens 3/8 2200Aliens 1/2-1 2700

Aliens 11/2-21/2 3700

Camelots0.5, 0.75, 4.5,

52700

Camelots 1-4 3600

Metolius (3- or 4-

cam)1-10 2700

Friends All sizes 3150

Quadcams 00 2250

Quadcams 0-5 3372

Chocks

Black Diamond

Stoppers6-13 2250

DMM Walnuts 3 2475

DMM Walnuts 4-10 2700


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HB Curves 2-9 2700

Lowe Tri-Cams 1.5-7 2500-4500

Wild Country

Rocks2-10 2700

It is also important to note that a minimum of three devices are used to form a rescue load

anchor. See "Load distributing anchor" later in this chapter.

The strength of bolts depends on many factors. If all other things are equal (skill of theperson placing the bolt, type of bolt, etc.), then the rock itself will be the strength limiting

factor. Assuming reasonably hard rock (e.g., granite), a 3/8" x 3" Rawl 5-piece

construction type bolt will have both shear and tension strengths of about 5,000 lbf.

RAPPEL DEVICES

ATC

The "Air Traffic Controller" and many other belay devices of similar design are usedprimarily for belaying, but they are also excellent devices for rappelling. They are light

and small and don't twist the rope.

Mnter hitch

The Mnter hitch is a knot that provides friction for belaying or for controlling the

descent of a rappeller. It works best with a pear-shaped carabiner (a "pearabiner"). The

obvious advantage is that it doesn't require special gear-but it does twist the rope.

Yosemite technique

The Yosemite technique uses only carabiners. Two carabiners form the platform, and one

or two across the platform form the brake bar. The two platform carabiners have their

gates on opposite sides to form a solid base. Standard ovals work best because of theirsize and symmetry. This technique requires no special gear and doesn't twist the rope.

PULLEYSGeneral purpose

Technical rescue presents many opportunities to use pulleys. The simplest is a direction

change, and a more complex application is a mechanical advantage (MA) for raising astretcher.

A pulley is essential for these applications because of the friction of any alternative

device (e.g., a carabiner). A pulley is about 90 percent efficient while a carabiner is about

50 percent efficient. We use a ball bearing unit made for rescue applications.

Prusik mindingpulleyThe Prusik minding pulley (PMP) is especially designed for a belay technique that we

discuss later. The side plates are sized to keep two tandem Prusik knots in place when

used as the belay for a raising.Edgeroller

The edge roller is a special purpose pulley for use on a sharp edge to prevent ropedamage and to minimize friction. The big disadvantage is its weight.

EDGE PROTECTORS


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We use CMC Ultra Pro plastic edge protectors for the main and belay ropes. They are

lighter weight and much easier to transport than edge rollers. For edge guards, we use

pieces of a fire hose that can be opened and closed with Velcro. Edge guards are usedwhere friction is not a concern (e.g., for protecting the anchor rope or belay rope).

ASCENDERSAscenders are camming devices for climbing a rope. The same or similar units can be

used in hauling systems to hold the load in place and to get a new "bite" of rope.

Climbers prefer devices with handles that facilitate "jugging." We use the Rescucender,which does not have handles but is stronger and more appropriate for rescue-specific

systems.

STRETCHERS

We currently have two different stretchers-the aluminum Stokes and the Ferno/Thomson

(usually called simply "Thomson"). Each has a specific application and specific

shortcomings. Rescue equipment is packaged with the stretchers:

The following items are packed with the stretchers: 1 victim pad

1 helmet with Velcro attachment

3 20-foot, 1-inch orange slings for victim tie-in to the stretcher

10 20-foot, 11-mm dynamic ropes:

1 for victim or attendant tie-in to the main and belay ropes

2 for load distributing anchors2 for edge attendant tie-in

5 for anchors

several fire hose edge guards

2 edge protectors (CMC Ultra Pro) to protect the main and belay ropes from sharp

edges

custom tarp in the Stokes for sliding on snowThe following items are packed in the accessory bags attached to the stretchers:

2 Rescucenders

2 pulleys for the Z system (an MA system)

2 mini-Prusik minding pulleys (1 for the belay line, 1 spare)

2 pre-rigged yokes

1 load releasing hitch with carabiners

2 sets of 7-mm Prusik slings

1 approximately 6-foot, 8-mm Prusik sling (for passing a knot in the main line)

4 large pear-shaped auto-locking carabiners for the Stokes stretcher or 4 extra-

large auto-locking carabiners for the Ferno/Thomson stretcher

1 brake bar rack

2 48-inch slings for a tilt line

1 wrist restraint

1 helmet restraint

1 fully adjustable seat harness

1 pair goggles

1 stretcher nut wrench (not required for the Ferno/Thomson stretcher)


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Two hardware bags go with each stretcher. One is for setting up the main anchor and

the other for setting up the belay anchor.

The following items are in the hardware bags:

1 set of 8-10 cams

1 set of 9-10 stoppers

15 locking carabiners 3 large locking carabiners

1 Cordelette

12 24-inch slings

8 48-inch slings

1 load releasing hitch with carabiners

1 gear sling

Stokes

The aluminum Stokes gets the most use. This is the most useful stretcher for mountain

rescue applications because it breaks down into two sections and can be carried on a

backpack frame. It's light and compact enough to be carried by one person and is solidenough for vertical raisings and lowerings. A wheel can be attached to this stretcher.Ferno/Thomson

The Ferno/Thomson is a basket stretcher like the Stokes, but it's plastic with a metal

frame. The advantage of the Ferno/Thomson is that it slides easily over snow and is solid

enough for technical rescues. No wheel is available for this stretcher.

Sked

The Sked is basically a sheet of thick plastic that wraps around the victim. It's light and

can be rigged to a backpack, but it's an awkward shape when packaged. It's transparent to

X-rays, which allows X-ray examination of the victim before removing him. Anadvantage is that it works well in a confined space-generally not a consideration in

mountain rescue. We don't use it for technical rescues .

Rescue seat

This seat is a harness designed to backpack a victim. The seat is used to carry a victim on

flat, sloping, or vertical terrain. The nature of the victim's injuries must not preclude the

victim from being carried in a sitting position.Figure 4-1 illustrates the set up of the seat. Tie a figure-eight-on-a-bight at the midpoint

of a 20-foot, 11-mm dynamic rope. Tie the main and belay lines through the bight with a

figure-eight follow through. The rescuer must wear a seat harness and tie directly into

one end of this rope with a figure-eight follow through. Locking carabiners attach theadjustable-length blue suspension strap of the seat to the rescuer and to the main and

belay lines. The 11-mm rope must be longer than the blue strap of the seat. Attach the

other free end of the 11-mm rope directly to the victim harness with a figure-eight followthrough. Attach the main yellow lanyard of the seat to the main and belay lines with a

locking carabiner after the victim is secure in the seat. The victim's 11-mm rope must be

longer than the yellow lanyard. During a high-angle or suspended lowering or raising, therescuer's blue suspension strap is adjusted so that the victim's weight is supported

completely by the yellow lanyard. In lower angle terrain, the rescuer shortens the

suspension strap and carries more of the victim's weight on the pack-straps.


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The victim is carried in the diaper seat with the leg loops. The shoulder straps secure the

victim to the harness and must be adjusted so that the "Y" is located between the victim's

shoulder blades.Note that the 20-foot, 11-mm rope and the victim harness are not required for a carry that

involves only flat or low-angle terrain.

For more details, refer to the manual that is located with the seat.

Figure 4-1. Rescue Seat Rigging

BELAY AND LOWERING DEVICES

All the rappel devices described above can be used for belaying or lowering a singleclimber. For stretcher raising and lowering applications, however, a device must handle a

much heavier load. A possible rescue load consists of stretcher, attendant, victim, rigging,and gear-a total of about 440 pounds. We use the following devices for rescue

applications:Prusik slings with Prusik minding pulley

Two Prusik slings with a PMP is currently the best solution for belaying a rescue load.We use two three-wrap Prusik slings made from 7- or 8-mm diameter cord. The shorter


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Prusik is made from 53 inches of cord and the longer one from 67 inches. A concern with

this technique is the flexibility of the cord. If the cord is not flexible enough, it may not

grab the belay line in a fall. The pulley keeps the knots in place during the raising. Thisbelay system requires a skilled rescuer who has trained with this belay method. It also

requires a load releasing hitch (LRH) in case the knots lock up.

Brake bar rackWe use the brake bar rack shown in Figure 4-2 for lowering a rescue load, but we

consider it to be inadequate for belaying. We have shown in a test case that the brake bar

rack will catch a rescue load but will be destroyed in the process.

Figure 4-2. Brake Bar Rack

STRETCHER BASICSRigging

Rigging for a high-angle lowering or raising (where the stretcher is horizontal) is

illustrated in Figure 4-3. We use two lines for both lowering and raising-the main line andthe belay line. The main line carries the load (the stretcher). The belay line should carry

no load unless a problem arises. We tie large figure-eight knots into both of these lines at

the stretcher end. All loose ends of the rigging system should be tied off using the passback method or the half-grapevine knot.


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Figure 4-3. Stretcher Rigging

The following points should be noted when assembling the rigging:1. For the equalization yokes we use two 20-foot, 11-mm dynamic ropes. We use the

double-bowline-on-a-coil knot for equalization. The large auto-lock carabiners in the

accessory bag connect the yokes to the stretcher. We use a figure-eight-on-a-bight withsafety for the tie-in to the main and belay ropes. One yoke should be shorter and should

be used for the head to achieve a slightly head-up position. Pre-rigged equalization yokes

are in the stretcher accessory bag.

2. The attachment loops for the main and belay ropes are tied as figure-eight-follow-through knots. The height of the rigging from the top rail of the stretcher to the main rope

tie-in should be approximately 2 feet.

3. The attendant and victim tie-in uses a single 20-foot, 11-mm dynamic rope. The centralfigure-eight-on-a-bight knot should be very short and should be tied so that

approximately 6 feet remain for the victim tie-in. The longer section is used for the

attendant tie-in.


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4. The stretcher attendant must be in position to guide the stretcher as smoothly and

comfortably as possible down or up the wall. He must also be able to administer first aid

in case of a medical emergency during the lowering or raising. This requires anadjustable tie-in in addition to the fixed tie-in to allow the necessary freedom of

movement. We use two Prusiks to achieve this freedom of movement: One Prusik is

clipped to the attendant's harness to adjust his vertical position with respect to thestretcher. The other is fitted with a foot loop to release tension on the first Prusik so that it

can be adjusted.

5. Small end down is the preferred orientation for the large auto-locking carabinersclipped into the stretcher. The gates are always inward.

6. The stretcher tilt line should be attached to a reinforced cross-support for strength and

so that the line will not abrade.

Rigging for a vertical lowering or raising (where the stretcher is vertical) is simple andrequires only a secure attachment to the head end of the stretcher.Victim tie-in

Figure 4-4 illustrates the proper method for securing the victim in the stretcher. Girth

hitches must be tied at each end of the 1-inch-wide tie-in webbing and as necessary toaccommodate injuries. The top rail of the stretcher must not be used for the girth hitches.

Three tie-ins are used:The first tie-in should have the first wrap go around the chest and under the victim's arm

for a more secure torso tie-in and a less restrictive feel around the arms. Lower arms

should be left unrestrained initially and tied with the Velcro wrist restraint strap as the

last thing.The second tie-in is around the lower part of the upper body.

The third tie-in is for the hips, legs, and feet. Start the tie-in at the hips and use one half

of the 20-foot, 1-inch webbing for one side and the other half for the other side. Use thetwo ends of the webbing for the stirrups. These foot stirrups must be tied with a girth

hitch immediately on both sides of each stirrup. The preferred method is the crossed

stirrup shown in Figure 4-4. A slip knot must NOT be used because it can tighten aroundthe foot and cause loss of circulation or other such complication. Do not use a foot stirrup

if there is an injury to that foot or leg.

Pads should be used as needed to protect and secure the victim. Adaptations to the tie-inmay be dictated by special first aid considerations.


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Figure 4-5. Attendant Tie-in

Site selectionSelecting a site for anchors depends on the situation. Some important considerations are

loose rock; availability and location of physical features like cracks, flakes, trees, andboulders for placing anchors; edge features (important for getting started and rope

management); and adequate room for rescuers to work.return to top

ANCHOR SYSTEMS

For a technical lowering or raising, at least two strong anchors are required. Call one the

main anchor and the other the belay anchor. Both anchors must be "bombproof" becauseeach must be able to hold the rescue load, and the belay anchor must be able to catch a

fall if the main anchor fails. We don't discuss here the individual placements (e.g., slings,camming devices, chocks, pitons, bolts) needed for the anchor. The rescuer's rockclimbing experience in placing protection provides the expertise for "bomber"

placements.Load distributing anchors

A single placement is not considered adequate even for a belay anchor in climbing and

certainly not for a rescue anchor that must carry the load of victim, equipment, and

rescuer.

A system to distribute the load among several anchor placements is essential.The term "self-equalizing anchor (SEA)" is commonly used for this anchor system.

However, the system is not really self-equalizing. It distributes (not necessarily equally)

the load over the included anchors and allows for a reasonable change of direction. So weuse the more appropriate term "load distributing anchor (LDA)."

There are many ways to construct an LDA. We use the system illustrated in Figure 4-6.

The construction requires approximately 20 feet of 11-mm dynamic rope. It consists of abowline-on-a-bight knot with short and long loops to connect to the anchors and a

double-figure-eight knot to connect to the main or belay line.
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The following guidelines are important in constructing an LDA:

1. We use a three-point anchor system for the main and belay anchors. The angle betweenadjacent legs of the three-point system should be less than or equal to 30 degrees. The

length of the outer legs must be 12-15 inches (see Figure 4-6).

2. We use 5 locking carabiners. Doubled non-locking carabiners with opposite andopposed gates is an alternate method in lieu of a locking carabiner. Locking gates should

be on the side away from the rock, if possible.

3. The rope should be a 20-foot, 11-mm dynamic rope.

4. Extend the anchors to the LDA, not the LDA to the anchors. The maximum drop if oneof the anchors fails must be less than one foot. This means that the circumference of the

large loop must be less than eight feet.5. The angle between the outside anchor legs at the load should be less than 60 degrees.6. The system must not include a marginal anchor. If a marginal anchor fails, the entire

system is stressed unnecessarily.

7. Don't get so involved in looking for a three-point anchor that you overlook a naturalanchor (e.g., huge tree, big rock).

Load releasing hitch


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A Larson load releasing hitch (LRH) (see Reference 4-1) uses 20-foot, 8-mm accessory

cord, two pear-shaped locking carabiners, and one standard locking carabiner. Tying this

knot is easier with two people because the carabiners must be held in the proper position.Tie the ends of the cord with a figure-eight. Put one pear-shaped carabiner at the middle

of the cord. Tie a Mnter hitch with the doubled cord on the other pear-shaped carabiner

at least one foot away from the mid-point carabiner (see Figure 4-7). Pull the mid-pointcarabiner toward the Mnter hitch until it nearly touches, then reverse direction and pull

the mid-point carabiner away from the Mnter hitch until they are separated by about six

inches. Make several wraps around the doubled cord between the Mnter hitch and themid-point carabiner until there is just enough space left to push a bight of rope through

between the doubled cord just in front of the mid-point carabiner. Start with this bight

and chain the extra double cord up to the figure-eight, then lock off the chain. Use the

third carabiner to clip from between the double cord (just in front of the figure-eight) tothe mid-point carabiner (see Figure 4-8).

To release the LRH and extend it for use, unclip the third carabiner from the mid-point

carabiner and unlock the chain. Before undoing the chain, clip the third carabiner

between the double cord (just in front of the figure-eight) and completely around thedouble cord just in front of the mid-point carabiner so that the LRH cannot come

completely apart. The chain can then be undone and the wraps removed until the LRHbegins to extend.

Figure 4-7. Load Releasing Hitch, Part 1

Figure 4-8. Load Releasing Hitch, Part 2

LOWERING AND RAISING

Lowering systemsDuring a lowering, the main line to the stretcher is allowed to run through the loweringdevice slowly and uniformly. The speed is at the demand of the stretcher attendant. We

use the brake bar rack for lowering. The number of bars are determined by the load. The

rope must be passed over the first bar (see Figure 4-9). An LRH is essential for passing a

knot.


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The belay line is allowed to run through the belay device (tandem Prusik slings with

PMP) without holding the load. The belay must always be ready to take the load if

needed.

Raising systems

A raising involves pulling the stretcher up a steep wall. In almost every case, a

mechanical advantage (MA) system is required to accomplish this task. We use a Zsystem as shown in Figure 4-9. The main line is pulled in increments (bites) whose length

depends on what the Z allows. A clamp (e.g., Rescucender or triple-wrap Prusik) on the

main line holds the load while a new bite is taken. An LRH should be used between the Zsystem and the anchor in case a knot must be passed (see Passing a Knot).

The belay line is pulled through the tandem Prusik slings, which are tended by a PMP.

Very little slack should be in the belay line.


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Figure 4-9. Z System

Belay techniques for raising and lowering

Tests by various teams and agencies have cast doubt on traditional techniques for

belaying rescue loads. The articles by John Dill in the summer and fall 1990 issues ofResponse (see Reference 4-2) are required reading. These tests have shown that the

triple-wrap tandem Prusik knots with a pulley is a viable belay technique (see Figure 4-

10).


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We use two 7-mm Prusiks (tied with a double-fisherman's knot) of different length (53inches and 67 inches). Three wraps are used around the belay rope. Make sure the knots

are tied neatly with the bridges of the knots on the same side. Clip the two Prusiks and

the Prusik minding pulley (PMP) into a pear-shaped locking carabiner in the followingorder: long Prusik first, then the shorter Prusik, and then the pulley (again, see Figure 4-

10). Then clip this locking carabiner into the belay LDA in series with the LRH. When

properly positioned, the Prusik knots will be about 4 inches apart. The belayer must beexperienced in using the Prusik belay and must be very attentive to keep the knots taut

but free running. On a lowering, the belayer should hold both Prusik knots with one hand

and pull out some belay rope using the thumb and wrist to form a bight of slack (see

Figure 4-11 and Reference 4-1). The rope should be flaked so that it will enter the tandemPrusik system smoothly from the side without twisting. Reference 4-3 recommends that

the belayer should grab both knots and slide them along the rope, twisting the extended

hand 90 degrees for slack. The belay line should never have more than 4 inches of slack.When belaying a raising, the tandem Prusik may be tended by the PMP as the belay rope

is pulled through it. For passing a knot safely, two sets of Prusik slings must be available.

An LRH is required in case the Prusik knots lock up. After using the LRH, always re-tieit so that it will be ready for its next application.

Avoid using the belay rope without back-up for shifting the load during a raising or

lowering.


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Figure 4-11. Tandem Prusiks and Belayer on a Lowering

Passing knots

In case a lowering or raising over more than one rope length is required, tying ropes

together may be more advantageous than setting up additional anchors and systems for

raising and lowering. Passing knots in the main and belay lines requires considerableadditional training.

1. In the belay rope for a raising (the belay is not holding the load): Place a second set oftandem Prusik slings approximately one foot below (downhill of) the knot and clip them

to the LRH with a separate sling and locking carabiners (independent of the original

belay). Remove the PMP and place it with the second set of tandem Prusik slings belowthe knot. Remove the original tandem Prusik slings.

2. In the belay rope for a lowering (the belay is not holding the load): Let the knot get

close to the PMP. Place a second set of tandem Prusik slings above (uphill of) the knot

and clip into the LRH. Remove the original set and the PMP. The PMP can then beplaced with the second set of tandem Prusik slings. This leaves about a foot of slack in

the belay line until the stretcher is lowered a little to remove the slack.3. In the stretcher rope for a raising (using a 3:1 Z system): The Rescucender that ismoved to take a new bite can simply be placed on the other side of the knot. The load is

then pulled up until the knot is close to the Rescucender that is holding the load. Place a

Prusik (8-mm cord, triple wrapped) on the load side of the knot down at least 2 feetbelow the knot and clip it into the LDA. Set the Prusik to hold the load with minimum

movement when the load is transferred from the Rescucender. To transfer the load, the Z

system must be pulled just enough to allow the top Rescucender to be released. After thePrusik takes the load, the Rescucender and top pulley can be moved down past the knot

by extending the connection to the LRH about two feet. With this accomplished, the Z

system can be pulled again to allow the removal of the Prusik that was placed to hold the

load during transfer.4. In the stretcher rope for a lowering (extra Rescucenders normally used for raising are

available): Let the knot get to about one foot before the brake bar device (do not let the

knot get locked up in the brake bar). Attach a Rescucender down the rope below thebrake bar device, and clip the Rescucender with a sling and locking carabiner to the LRH.

Allow the Rescucender to take the load, then move the brake bar device to the other side

of the knot and clip it into the LDA (not the LRH). Release the LRH until the brake baragain takes the load, and then remove the Rescucender.


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Communication

The single most important thing for good communication is that one person is in chargeand has full control of the exercise. This person might be called the Safety Officer (SO),

Operation Leader (OL), or something else. We use the term OL. The OL is responsible

for everything (which doesn't mean that he does everything). The OL makes assignmentsfor each task that needs to be done and checks each setup to make sure that things are

done safely.

Communication be>omes important after the individual assignments are accomplishedand the raising or lowering is ready to begin. The OL coordinates the process. Initially,

the OL starts all actions. When the stretcher and attendant are ready to start moving,

however, the attendant initiates the actions. Only the attendant knows whether he wants

to start, stop, go faster or slower, etc.The method of communication depends on the situation. Simple voice commands work

well while everyone is at the anchor site. After the stretcher has moved away from the

anchor site, hearing the commands might be difficult. The OL should assign one person

to the edge to watch the stretcher's progress and relay commands as needed. Radiosshould always be available and used if necessary.

Some teams recommend a whistle code, and it has some advantages. A whistle is easilyheard, and the source can't be confused (assuming only one whistle is on site). However,

you must remember a possibly complex code. A simple "one blast for start" and "two

blasts for stop" isn't enough.

Tag line

A hand line attached to the stretcher can be used to guide the stretcher from the ground

and to help the stretcher attendant in directing the stretcher and providing an offset from

the direction of the main line.

Guiding line

An additional rope between the anchor and the ground can be used to provide an offset so

that the stretcher can be moved over such obstacles as large overhangs. The stretcher isattached to the guiding line with a tether sling at the yoke and a pulley. This guiding line

is under little tension and can be hand held by a rescue team on the bottom.

Tracking line

This line is similar to the guiding line, but it is anchored at the bottom and is under

medium tension. The tracking line can be used to position the stretcher out beyond major

obstacles such as overhangs during high-angle raisings and lowerings.

TRAVERSING SYSTEMS (also called TYROLEAN TRAVERSE)

See Reference 4-4 (Reed Thorne: "Offsetting The Technical Evacuation" 1997 North

American Technical Rescue Symposium) for a detailed discussion. Reference 4-5provides detailed illustrations.

Highline

A traverse is a technique to cross a river or deep canyon or even to descend a very steepface. Basically, this technique requires a bombproof anchor on both ends with lines

strung across. Be aware that tremendous forces can be generated on this system. In

general, understanding the physics of placing a load on ropes and anchors for rescue

techniques is important; for the highline, it is critical.


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Figure 4-12 illustrates a basic highline. The main or track line, a low-stretch 11-mm rope,

is anchored on both sides, and the load hangs off this line. The force on the anchors and

the rope is a function of the sag in the rope. A table in Reference 4-6 shows the tensiongenerated for various spans, sags, and loads . One revealing example is that for a 100-foot

span with a 4-foot sag and a 200-pound load, the tension is 1250 pounds. Since a safety

factor of 10 is recommended for such systems and assuming a perfect anchor and a ropestrength of 6000 pounds, it is clear that the safety factor is not achieved. A 10-foot sag for

a 100-foot span is required to obtain a safety factory of 10. For a 200-foot span, a 20-foot

sag is required. Without a load, two people can pre-tension the track line without an MA.A 3:1 Z system with no more than four people pulling should be used to adjust the

tension with the rescue load in the middle of the span (see Reference 4-3).

Figure 4-12. Highline Rigging

The safety line, a low stretch 11-mm rope, provides the necessary back-up or belay. Therescue load, consisting of victim, attendant, and stretcher is attached to the track and

safety lines with a 2-inch double pulley. The tag lines, 11-mm dynamic ropes, are usedfor moving the stretcher with victim and attendant across the track line. Both lines should

be tied into anchors via tandem triple-wrapped Prusiks and a PMP. Both sides need an

attendant to move the tag lines through the Prusik belays. A brake bar and a Z system can

be added on either side if a lowering followed by a raising is required.

Kootenay highline

This highline system uses only one track line, a low stretch 11-mm rope. The tag lines,

low stretch 11-mm ropes, are used as belay lines. Figure 4-13 (see Reference 4-5)illustrates the rigging for the track line and tag lines at the anchors on each side.

The track line is tensioned with a 2:1 MA that is attached to the rope with tandem triple-wrapped Prusiks. Use only ONE person to pull for tensioning without a load. Failure tofollow this rule could overstress the track line when a load is on the line. With a rescue

load hanging from the track line, up to a total of six persons may be used with a 2:1 MA

to tension the track line. The tension should be backed off when it is not needed any more

to clear obstructions.The maximum practical length of this highline is 300 feet.


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The tag lines are connected to the anchor with tandem triple-wrapped Prusiks and a brake

bar on one side and a 2:1 MA on the other side. The two tag lines are attached to the

pulley with triple-wrapped Prusiks and a figure-eight. Figure 4-14 (see Reference 4-5)illustrates the rigging. The pulley should be a Kootenay pulley with three holes to attach

the stretcher and the two tag lines or a two-inch pulley with a rigging ring or plate clipped

into the pulley with a locking carabiner. Each tag line must be secured like a belay line. Aperson on each end must operate the belay system in complete coordination with each

other to make sure that there is never any slack in either tag line.

Figure 4-13. Kootenay Highline System


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Figure 4-14. Kootenay Highline Rigging

REFERENCES

4-1. Kenneth N. Laidlaw: "Considerations for Technical Rope Rescue and Introduction ofTAC Rope Kit." 11/20/96, www.basarc.org

4-2. John Dill: "Are You Really on Belay?" Response, Summer and Fall 19904-3. Padgett, A. and Smith, B. (1998) On Rope: North American Vertical RopeTechniques for Caving, Search & Rescue, and Mountaineering. Huntsville, Alabama:

National Speleological Society.

4-4. Reed Thorne: "Offsetting The Technical Evacuation" 1997 North AmericanTechnical Rescue Symposium.

4-5. Rick Lipke: Technical Rescue Riggers Guide. Conterra Technical Systems Inc. 1997

4-6. May, W. G. (1973) Mountain Search & Rescue Techniques. Boulder, Colorado:

Rocky Mountain Rescue Group, Inc. 301 pp.4-7. Setnika, Tim J. (1980) Wilderness Search & Rescue. Boston: Appalachian Mountain

Club.

4-8. Mountaineering: The Freedom of the Hills, Sixth Edition, 1998. The Mountaineers.Edited by Don Graydon and Kurt Hanson

4-9. Vines & Hudson (1989) High Angle Rescue Techniques. NASAR.

4-10. CMC Rope Rescue Manual.4-11. Steve Hudson: Myths and Urban Legends of Rope and Prusik Cord Selection for

Rescue. North American Technical Rescue Symposium, Long Beach, CA, November

1997

technical rescue

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