transceiver search techniques vary depending on the number of antennas
in your beacon. Multiple-antenna
beacons display a direction
indicator that points the way to the victim whereas
have you locate the victim by manually searching for the strongest
signal. Many of the instructions on this page apply to both types
of transceivers. However, the coarse search
explained on this page (where you follow the direction indicator)
requires a multiple-antenna beacon. Be sure to read the
owner's manual that was supplied with
your transceiver and to practice regularly!
information on this page is divided into things to do
before you leave the trailhead,
what to do during and immediately
after the avalanche, the signal search
that helps you locate the first signal, the
coarse search that gets you within
a few meters of the victim, and the fine
search which puts you over the victim. Remember that
probing (aka pinpointing) is an important
skill and shoveling takes a significant
amount of time.
Have good, high-quality batteries
in your transceiver.
your partner's) transceiver. Always carry sturdy
Wear your transceiver under your outer layer where
it cannot be damaged or removed by obstacles (such
as trees and rocks). Your pants pocket may be acceptable
(although it may be more susceptible to impact damage).
If you remove clothing due to warm weather, remember
to keep your transceiver under your remaining clothes.
Use safe travel techniques (e.g., route selection,
only expose one person at a time, etc).
Make sure the scene is safe. It is important that
rescuers are not exposed to additional avalanche
hazard. The actual avalanche path is usually safe
if there isn't significant "hang fire"
remaining above the slide.
Once in a safe location (a.k.a. an "island
of safety"), have everybody change their transceiver
to either the off or search mode. If I had a nickel
for every training that stumbled due to a transceiver
being left in the transmit mode...
Note that many transceivers can be set to automatically
switch back to transmit
. This can cause confusion if non-searchers
change to search mode and then unknowingly return
to transmit mode. It's usually best if non-searchers
turn their beacons off
after arriving at
Determine the number of victims. The number of victims
will influence how the search should be organized
(e.g., whether you should perform a
multiple burial search
when to call for additional help, etc). You can
determine the number of victims by interviewing
witnesses, using your transceiver, and by physical
clues (e.g., finding two different brands of skis).
Consider calling for additional help. When you should
call for help is very situational dependent. Be
sure to consider (1) how many additional minutes
the victim will be buried if you do place the call,
(2) how fast the rescuers can respond, and (3) how
you will transport the victims once you do locate
If you are the sole rescuer, the several minutes
it will take to call for help might be better
If you have two or more searchers and one victim,
having the second searcher call for help may
save valuable time getting medical personal
The decision to call for additional help is multifaceted
and complex. It is best to consider these factors
before an avalanche accident.
Look for visual clues (e.g., gloves, skis, etc).
If you see a glove or ski, check to see if it is
connected to a victim. There are many examples,
including avalanches that I have responded to, where
gear on the snow surface (e.g., a glove) was still
connected to the victim.
The goal of the "signal search" is to receive
a signal. Period. If you switch your transceiver
to search mode and receive a signal, you have already
completed the signal search.
The following illustrations show the appropriate
spacing for a 40 meter search strip width. Note
that with a 40 meter search strip, you should get
within 20 meters (half the search strip width) of
the sides of the avalanche.
Because it is much easier to move downhill than
uphill and because you don't want to repeat
the signal search, when in doubt, narrow your search
strip width. It is always better to spend a few
extra minutes searching a narrower strip than to
end up at the bottom of the slide and have to repeat
the signal search while hiking up hill. (Unfortunately,
if the last skier in a group gets buried, the search
must be done from the bottom.)
When using a
transceiver, slowly rotate your beacon in all orientations
(i.e., rotate your wrist 360°) to increase the likelihood
that your antennas will align with the victim's.
Keep your gloves on. It's tempting to take them
off and drop them in the snow when you are working
with your transceiver, but you'll want them
when probing, shoveling, and providing medical care.
Remember, the goal of the signal search is to
receive a signal. You should move
quickly and deliberately. Locating the initial signal
depends more on choosing an appropriate distance
between search paths than on transceiver skill.
The goal of the "coarse search" is to get within
two or three meters of the victim. The coarse search technique
varies depending on whether your avalanche transceiver has
indicator (i.e., has multiple
antennas). These instructions only explain the directional
(i.e., the arrow or lights). If the
distance numbers increase, turn around and follow
the direction indicator in the opposite direction.
(The direction indicator can point in either direction
on the flux lines shown in blue, below. You want
to be moving closer to the victim. A few transceivers
will tell you to turn around if you are moving away
from the victim, but it's still important to look
at the distance indicator. As you follow the direction
indicator, slowly turn to re-orient the beacon so
the arrow is pointed inline with the beacon.
Continue to follow the direction indicator. It will
follow the flux lines as it guides you to the victim
in an arc as shown here.
It is not unusual for transceivers to give an occasional "blip"
in the wrong direction. Pause for a moment while
holding the transceiver very still to allow the
direction indicator to settle.
If the indicator gives conflicting directions (e.g.,
left, right, left), choose one of the directions
and begin walking. The direction indicator will
resolve the conflict as you near the victim.
Move relatively quickly while the distance is more
than 10 meters. Remain calm and move deliberately.
This is a bad time to fall and injure yourself.
When the distance is less than 10 meters, slow down
and pause for a few beeps each time the direction
indicator changes direction.
When you are within two or three meters, you have
completed the coarse search.
On most transceivers, the
will disappear when you are within
two or three meters of the victim. If your transceiver
continues to display the direction indicator, you
should ignore it at this point and focus on the
as explained in the
The goal of the "fine search" is to get as
close to the victim as possible so you can begin
Only one rescuer is needed for the fine search.
Additional rescuers should begin assembling their
. If there are
multiple victims, additional rescuers should begin
a multiple burial
your transceiver just above the snow, slowly
move it left/right and forward/backward while looking
for the lowest distance.
During the fine search, it is important that the
transceiver always points in the same direction
(i.e., don't let it rotate as you swing your
arm to the side). Similarly, get on your knees and
keep the transceiver very close (e.g., a few inches)
above the snow.
Continue to slowly move your hand from side-to-side
looking for the lowest number, and then forward-and-backward
while again looking for the lowest number. This "bracketing"
approach helps you locate the strongest signal.
You may find it helpful to put your foot on the
spot with the lowest number and move it only when
you find a lower number.
Repeat this bracketing process until you find the
spot on the snow with the lowest number (i.e.,
when moving the transceiver left/right or forward/backward
causes the displayed distance to increase).
shows how the Barryvox Pulse
can help you perform the fine search "bracketing.")
Don't waste a lot of time on the fine search. Performing
one or two brackets in each direction should take
less than 30 seconds.
When you find the lowest distance, begin
until you strike
something, leave the probe in place and begin
If your transceiver has fewer than three-antennas,
you may find more than one location on the snow
that gives a low reading. These are
. If this occurs,
simply bracket until you find a low reading (Step
3) and begin probing at that location. You may need
to continue probing beyond the starting location,
but you know you are very close to the victim and
that you will find him if you use proper probing
technique. (See the discussion of
for details on the
distance and probing time.)
If you have multiple
, you will need to use special techniques
to locate the additional victims.