Whether you're hiking or climbing through the mountains in the U.S. or on an expedition to climb Mt. Everest or another tall peak, the threat of an avalanche is the same, anywhere
there's snow fall. Many people have lost their lives in avalanches.
Consider this real-life diary submission from a man hiking in Nepal:
Friday, 10 November. Ang Tsering and I ask all to pack essentials
in their day packs for possible bailout if this [snow] continues. We
meet in the dining tent (resurrected). I hear Ang Tsering yell
"avalanche!" and the next thing I know I'm doubled over -- pinned
against the table. We all get out OK, and we're clearly blessed. The
table either saved us or the avalanche had run its course.
Three of our tents were eight feet deep and five people would have
been buried had they still been packing. Three tents and the dining tent
were totally trashed. Most people were now without duffels, sleeping
bags or day packs. We decided to get the hell out and return to dig out
our tents when this stopped.
About ten minutes down the trail, the route looked suicidal. Below us
in a narrow valley, a group was trying to dig a trail. In 30 minutes, we
moved about 50 feet. Visibility was 200 feet, snowing in sheets, and we
could hear but not see avalanches booming on all sides. This was a
doomsday scenario; there we were, standing in this mess without food,
clothing or sleeping bags. We went back and built a snow platform behind
a safe rock.
We'll take a quick look at the necessary conditions for an avalanche,
then study how you can survive an avalanche - or even avoid it
altogether - during your next ice climbing, snowboarding, or skiing trek in the snow.
"Lean snow winters are often dangerous avalanche winters. That's
because the thin snow cover in November and December turns to weak sugar
snow. When heavier snow falls in late December and in January, that's
when the problems begin. The snowpack becomes the classic house of
cards, with a layer of slab snow sitting on top of the sugar snow. The
slightest disturbance can bring it down," says Knox Williams, director
of Colorado Avalanche Information Center (CAIC).
Williams insists the keys to fewer avalanche deaths are education and
prudence, especially when people visit deep, rural regions.
Why Avalanche Beacons Don't Always Save Lives
Doesn't technology find and save most of those caught in an
avalanche? "Yes and no," says Williams. "Yes, because avalanche beacons
have saved several lives the last few years by allowing a buried victim
to be found quickly; but also no, because once a person is caught in an
avalanche, luck may play a larger role in survival than rescue
equipment. Less than half of the people with beacons who are buried by
an avalanche actually survive. That's because a beacon cannot save you
if you are severely injured or buried deeply.
"Wouldn't it be better to not get buried at all?" Williams
continues. "The key to survival is avoiding accidents altogether
through knowledge and good decision-making in the backcountry."
How Serious is the Threat of an Avalanche?
Well, how serious is the threat of an avalanche anyway? How worried
should you be?
Because snow avalanches are really a whole season's snow released
down a mountainside at once, an avalanche may release tremendous forces
and are a serious threat to the winter traveler.
If you like skiing or snow-related activity, it is very important
that you learn how to avoid being in an avalanche, and increase your
chances of survival if you find yourself in one.
Many Factors Contribute to an Avalanche
There are literally a ton of factors that can contribute to avalanche
conditions. The possible combinations of factors are endless, and the
forecasting of a possible avalanche will often require the evaluation
of extremely complicated situations. However, there are many practical
things you'll read about here that can be helpful to you.
Survival Tip: both experience and statistics show that fully-buried
avalanche victims who are still alive when the avalanche stops moving
must usually be found and dug out within 15 minutes to have any
reasonable chances of survival.
To tell the truth, in North America the
chances of an organized professional rescue team arriving in that time
frame are pretty slim unless the accident happens in an area where an
avalanche safety program operates. But even in such areas, alerting a
team and quickly mounting an organized rescue may well take longer than
the 15-minute window of opportunity.
Your Team Must Be Familiar with Avalanche Rescue
Therefore the efforts of those who survive or witness an accident
(often called 'self rescue techniques' by those in the know) are
absolutely crucial to the survival of any victims. If those on the scene
fail to at least locate any buried victims, it is unlikely that the
organized rescue teams will arrive in time to make a live recovery.
Survival Tip: Don't just take a group of people up in the snow. Be sure to discuss
what kind of conditions (see below) can trigger an avalanche, and also what to do
should your group be caught by surprise. Knowing the ins and outs of avalanche danger
can go a long way -- but sometimes you may still be caught unexpectedly. After reading this
article hopefully the chances of that will become slim.
Self Rescue Procedures
So the makeshift locating and possible rescue procedures should be
understood and practiced by those planning a few days in the snow, in order for the event of an avalanche self rescue to truly be fast and efficient.
Every situation has some rules all its own, but these general
guidelines should give you a good footing (no pun intended) when you're
trying to cope with the fallout (pun here is intended) of an ugly
To Avoid an Avalanche, Learn How to Read the Terrain
Slope steepness - Slopes of 30-45 degrees are the ones most likely
to avalanche, but anything in the neighborhood of 25-60 degrees can do
so under certain conditions.
Slope profile - Convex slopes are clearly the most dangerous; stay
away from them when you can, especially during the period from late
December thru January. Concave slopes are less dangerous, but they can -
and sometimes do - avalanche.
Slope aspect - North-facing slopes are the most likely to avalanche
during the dreaded middle of winter. But south-facing slopes can become
dangerous in the spring and during sunny days, as the sun begins to
rise higher in the sky.
Also, slopes that garner snow during windy conditions are dangerous
because wind-borne snow adds to their rapid accumulation; the hard,
hollow-sounding wind slab may develop there. However windward slopes
(those slopes sitting into the wind) generally have less snow and
benefit from wind compaction.
Ground cover - Areas with large rocks, trees and heavy brush here
and there are a good help in anchoring the snow on the mountain. Smooth,
grassy slopes are much more dangerous.
How to Read the Snow and Avalanche Triggers
New Snow - You should especially suspect dangerous conditions with a
foot or more of soft, new snow. However, conditions can always be
hairy. Stay on your guard whenever you're around snow-covered mountain
Rapid snow settlement is actually a favorable sign. Look for
settlement cones around tree trunks and over rocks. Moist, dense
precipitations create those sought-after settlement cones, because the
snowfall settles rapidly. During windy periods all bets are off however, as even this
snow can suddenly become very dangerous.
Lack of settlement is a danger sign; loose, dry snow can easily trigger an avalanche.
Dangers from Dry Slab Avalanche
Then there's the "dry slab" -- this is the biggest and deadliest avalanche that occurs when the snow begins to slide
as one big unit, then breaks apart and picks up speed and more snow as it slides down the mountain. Many
people have been crushed and lost their lives in this monster. Dry slab avalanches are responsible for nearly all avalanche deaths that occur. Snow in dry slab avalanches has settled in layers, and these layers rest on one another. Just the right amount of weight or movement (say, from a person) can send the whole mountain side down the mountain.
Old Snow - When the old snow depth is sufficient to cover natural
anchors, such as rocks and brush, additional snow layers will slide more
readily. Also, the nature of the old snow surface is important. Rough
surfaces are of course favorable for stability; any smooth surfaces,
such as sun crusts, are not.
A loose, underlying snow layer is more dangerous than a compacted
one. You can check this with a ski pole, ski, or snowshoe.
Ever wonder why you see those pro skiers banging the ends of their
poles into a deep snow before beginning a day of skiing? Now you know.
Crystal Types - All snow is not created equal. You can readily
observe general crystal types by letting them fall on a dark ski mitt or
parka sleeve. Small crystals, such as needles and pellets, result in
more dangerous conditions than the usual star-shaped crystals.
Avalanche Weather Conditions
Wind - Sustained winds of 15 m.p.h. and over during a storm cause
trouble fast. Snow plumes from ridges and peaks indicate that wayward
snow is being blown onto these slopes during clear weather and that
dangerous conditions may be developing, even though it is not storming.
Temperature - Snow persists in an unstable condition longer under
cold temperatures. It settles and stabilizes more rapidly during warmer
weather that's near or above freezing.
But beware high and rapidly rising temperatures in the spring
months. They may result in wet snow slides, particularly from south-
Beware of any rapid change in temperature. Shadows creeping across a
slope may change temperatures enough to create dangerous conditions.
Snowfall Rate - Snow falling at the rate of one inch per hour or
more increases avalanche danger rapidly.
Old Slide Paths - An avalanche path that has slid once will slide
again. Look for old scars in timber and avoid steep gullies and steep,
Recent Avalanche Activity - Look around; if you see new avalanches
you should suspect dangerous conditions.
Sound and Cracks - If the snow sounds hollow, particularly on a
slope full of wind-blown snow, conditions are probably dangerous; if the
snow covers cracks that are found running in the snow, slab avalanche
danger is high.
Check weather forecasts. For particular information, contact a US
Forest Service Snow Ranger or the nearest winter sports area ski
Choosing a Route to Avoid an Avalanche
* The safest routes are on ridge tops and slightly on the windward
side away from the ridges' edge.
* Windward slopes are almost always the safest.
* If you cannot travel on ridges, the next safest route is out in the
valley away from the bottom part of slopes.
* Stay high and near the top if you must cross dangerous slopes or
avalanche paths; if you can see old or new avalanche fracture lines, be
sure to avoid them and other similar areas.
* Go straight up or down if you must ascend or descend a dangerous
slope; do not make traverses back and forth across it.
* Take advantage of areas of dense timber, ridges or rocky outcrops as
islands of safety. Use them for lunch and rest stops and spend the least
time possible out on the open slopes.
* Snowmobiles must not travel across the lower part of slopes, and
especially not across long, open slopes or known avalanche paths.
* Look for, and obey, all signs or other warnings of avalanche
Avalanche Precaution - Rules of Thumb
* Only one person at a time on a suspect slope: all others watch the
person that may be in danger.
* Remove ski pole straps and ski safety straps; loosen all equipment,
put on and fasten mitts, cap, and all other clothing before being
exposed to avalanche danger.
* Carry and use an avalanche cord, as well as a sectional probe.
What To Do if You're Caught in an Avalanche
* Discard all equipment (skis, poles, snowboard, snowshoes). If you
have a snowmobile, leave it.
* Remember the terrain. Be prepared for falls over cliffs, collisions
with trees, and the stop in the runout zone.
* Seek shelter behind rocks, trees, vehicles.
* Crouch low and turn away from the avalanche.
* Cover nose and mouth (snow can fill your nostrils and mouth)
* Brace against impact, hold onto trees, etc.
* Do not cry out or open your mouth as the avalanche is occurring.
As the avalanche slows
* Pull hands and arms to the face and make an air space.
* Thrust and kick to the surface just before the snow comes to a
* Try to stay on top and work your way to the side of the avalanche.
* Thrust an arm toward the surface.
When the Avalanche has Stopped
* Try to dig yourself out.
* Call out when you can, especially when rescuers are near.
* Though we're sure it will be close to impossible, try to stay calm.
The most important thing you can have at that moment is a clear head.
If You are the Survivor
* Mark the place where you last saw the victims.
* Search for them in the fall line and directly below the last seen
* Search the area of greatest snow deposition first.
You are their best hope for survival. Do not desert those
trapped and go for help unless you are certain help is only a few
Remember, you must consider not only the time for you go to get help,
but the time required for help to return. Also, the victim has only a
50% chance of surviving for an hour.
If you do go for help, mark the route so a rescue party can follow it
If You're in a Vehicle and Buried by an Avalanche
Now if you are in a vehicle, the first thing to do is turn off the
engine. Do not smoke or use matches. While it may not be obvious at
first, these activities will waste what precious air you have - a
Open a window and check for depth of burial with some kind of stick,
pole or probe. Do not leave the vehicle unless you feel sure it is safe
to do so or you are in a remote location.
If you have a two-way radio, keep it turned on; it may quickly become
your best friend in this situation. Use it to call for help.
Search & Rescue After and Avalanche
The two very best ways to initialize a good rescue if you happen to
survive, witness, or come upon an avalanche accident are:
1.) To make sure at least one of you possesses and can work an
avalanche transceiver, which helps you find those lost in the snow, and;
2.) To always travel and work in a group when you are traversing through the snow.
A number of years ago all manufacturers of avalanche transceivers
agreed to manufacture only transceivers that transmitted and received on
a frequency of 457 kiloHertz (or 457 kHz). One of the benefits of using
this frequency is that it allowed a new and faster searching method,
called the "induction-line" technique, to be employed. Up until that
time transceiver searches were conducted using an older and usually much
slower technique called the "grid-search technique." This simple
improvement has saved many a life.
Learning the induction-line technique is a practical skill and it
should be practiced several times a season or, better still, at the
beginning of each outing. Like most techniques, this procedure cannot be
learned from a simple description alone.
In addition, at the beginning of each trip and at critical points
thereafter, avalanche transceivers should be checked periodically to
ensure the device is in working order.
The basis of the induction-line technique utilizes the fact that an
avalanche transceiver actually has an electromagnetic field that
surrounds it each time the transceiver transmits. This field has a
three-dimensional shape somewhat like an apple, surrounding the device
and whoever is using it at that moment.
Using the transceiver in 'receive' mode, the searcher moves or
orients their transceiver until it is passing along one of the "flux
lines" of the electromagnetic field. That "flux line" is then followed
like a railroad track curving into a station (naturally the flux lines
are not actually visible, but you are in effect following an
induction-line or flux line - hence the name of the technique).
Once you have picked up a signal, you begin by carefully scanning to
find the direction in which the signal is strongest. You now quickly
move in that direction for a distance of about 15 feet (5 meters). If the signal immediately gets weaker,
consider moving in the opposite direction instead. You always want to
travel in the direction that makes the signal stronger or sound louder.
On beacons with visual indicators, you want more lights or bars
illuminated on an LED or LCD display.
Some points to keep in mind when pinpointing
* Particularly if using transceivers with loudspeakers, only one
person should home in and pinpoint the signal.
* When homing in on the victims location, move as quickly as possible
and turn the volume of your transceiver down whenever possible.
* When pinpointing the final location, use a logical pattern and slow
down so as not to miss the strongest point.
* Mark the area where the signal is strongest.
* Probe the marked area using a logical pattern.
* When the victim is hit with the probe, do not remove the
probe. Notify the rescue leader of the hit. Note the approximate
depth of the victim. Begin rescue digging.
Victim Recovery and Rescue Digging
Digging for a victim is tiring and can take actually longer than the
search, so it is important to be as efficient as possible. Here are some
tips that make the recovery process easier and faster.
If the victim is deeply buried, begin digging well away from the
probe. As a rule of thumb, the hole required to expose the victim will
be at least the square of the depth: that is, if a victim is buried 6
feet deep (or 2 meters), the hole required to remove the victim will be
at least 6 feet by 6 feet.
Dig on the downhill side of the probe and throw snow downhill.
Too many people digging at once get in each others' way. It's a
better idea to use only a few diggers at one time. Besides, diggers
should be rotated often anyway - every few minutes if possible. As soon
as one begins to tire or slow down someone fresh should take over.
There's no room for ego here. Time is absolutely of the essence.
Deep holes may require tiers with diggers on each tier moving snow
from the bottom to the surface.
When the victim is found, uncover the head and chest immediately,
clear the mouth and airway, and begin first aid while the rest of the
victim's body is still covered.
If a transceiver search is unsuccessful, secondary procedures - such
as setting up a probe line - must be used.
Setting Up a Probe Line
If a transceiver search is unsuccessful, probe around likely burial
areas; for example, around found articles belonging to the victim(s),
around trees, rocks, in gullies or deep deposits. Basically anywhere
known or suspected to be the victim's line of travel.
Make sure to mark recently probed areas. With every second counting,
you don't need to look over the same real estate twice.
If probing around found items or in likely areas of burial is
unsuccessful, an organized probe line may be useful if there are enough
searchers on the scene to set one up. A probe line needs at least 6
searchers to be efficient. If there are not enough searchers, continue
with the probing of likely areas.
Three Hole Per Step
Recent Research (Auger and Jamieson, 1997) indicates that the three
hole per step technique is the most efficient means of probing and can
be effective even with relatively small numbers of probers.
To set up the probe line, establish the most likely area of burial.
Line up searchers in a straight line and space them apart approximately
from wrist to wrist. Searchers probe three times: once directly in front
of them, then reaching left and right with their probe about 1
1/2 feet (or about 45 cm) on either side of the middle hole. Searchers
take one normal step forward and repeat the process.
As noted above, the '3 hole per step technique' has distinct
advantages, particularly where a small group of rescuers must search a
large area. It has been widely adopted throughout many areas as one of
the quickest, easiest ways to find someone trapped under an avalanche
The Open Space Coarse Probe
On particularly rough terrain or when fewer rescuers are available,
probers spread out from fingertip to fingertip. Each prober then inserts
their probe once just outside of the left foot, then again just outside
of the right foot. This technique provides much of the efficiency as the
'3 hole' technique, but the speed with which the area is covered
Probing for a Vehicle
The Fine Probe
As noted above, the '3 hole per step' technique has distinct
advantages, particularly where a small group of rescuers must search a
large area. But when a protracted time has passed without success (many
hours or even days) and the rescue team leader feels there's very little
hope of finding a buried avalanche victim alive, an alternative probing
technique may sometimes be employed. The "fine probe" technique has a
very high probability of detection (near 100%). Due to the fact that it
uses a much closer spacing, the amount of time and manpower required to
search a given area is greater and can take as much as five times as
long to probe a given area as with the '3 hole per step' method.
Self Rescue on Roads
Carrying out a self rescue where an avalanche-covered road strewn
with vehicles may be involved will follow a similar procedure to that
described above. There are some specific considerations, however:
* Stop in a safe location.
* Direct vehicles and people to a safe area.
* Check dimensions of avalanche and determine whether vehicles could
caught in it.
* Before carrying out any rescue procedures, carefully assess the
further avalanches. (Remember, you do not have as much information as
you might in
a backcountry situation.)
* If you feel the situation is unsafe and that no one is buried in the
avalanche, simply send for help and wait for assistance.
Getting Help After an Avalanche
Which brings us to the last real issue: getting help. If help is
nearby, consider the safety of those going out, how many will be left to
continue searching, the probable time before rescue teams arrive, and
the survival chances of any victim(s) during that time.
Also, before going for help note the following information:
* the exact location of the accident;
* access (road, trail, helicopter);
* time of accident;
* weather and snow conditions;
* if number of people buried, how many;
* rescuers on site
Continue searching for as long as you can, but make provisions for
the feeding, sheltering, and safety of searchers if an extended hunt is
As we've said at the beginning of this article, no descriptions can
prepare you for every eventuality; but we feel we've given you a
fighting chance. Remember, even experienced mountain climbers like the
ones trekking thru Nepal at the beginning of this little composition
discovered what can happen in an instant during an avalanche.
Also, if it weren't for the watchful eyes of the man who wrote that
Nepalese diary entry and his associate, many of their friends might
still be lost in the mountains of Nepal if they hadn't been on the
lookout, and if all those involved hadn't worked together thru the whole
ordeal. That, dear friends, is probably the most important avalanche
lesson we can give.
New Inventions for Avalanche Survival: The Avalanche Airbag
There's been a lot of news about the airbag system for saving lives in an avalanche. It's worn in a backpack and when an avalanche is about to hit, the person wearing the pack triggers the airbag release, which inflates and (as it's designed) helps the person ride on top of the avalanche, rather than underneath it where most deaths occur. Enough people have been in avalanches and tested this system that we're now getting a clear picture that it isn't as reliable as early reports indicated. In other words, even if you buy the Avalanche airbag pack and use it in an avalanche, you can still end up dead. It is not a guaranteed life-saver.
Avalanche airbag - snow enthusiasts split on use of avalanche survival aids
The Avalanche airbag may even be a bit dangerous. Let me explain: It may give the wearer a false-sense of security and thus cause that wearer to be a little less cautious up in the snow.
Survival Tip: If you're going to wear one of these packs -- kudos to you. It just might save your life. But don't let it give you a false-sense of security and make you less cautious up in the snow. Be cautious and be smart up in avalanche country. People die every year. People are crushed, their bodies turned into pretzels. Know the terrain. Proceed with caution.