Avalanche Safety Gear

The best strategy for surviving an avalanche is to avoid being caught in one. All backcountry skiers, boarders, and snowshoers should be trained in avalanche awareness and should be knowledgeable about the conditions and terrain they're entering.

The following avalanche safety gear, as well as the knowledge and skills to use it, should be carried by everyone heading into the backcountry:

• Transceiver
• Probe
• Shovel

Transceivers

Avalanche transceivers (also known as beacons) are designed to help a rescuer locate a buried victim in the least amount of time possible. Although most beacons in use today are fairly intuitive to operate, it is important to practice using them on a regular basis.

Types of Transceivers

Transceivers both transmit and receive a signal at a frequency of 457kHz. (Older 2.275kHz beacons are obsolete and should be discarded). Beacons available today differ in the way they collect and present information from a received signal.

• Analogue beacons beep louder as you get closer to the victim. Often the audible signal is combined with an optical indicator that uses lights or arrows to display signal strength as you navigate toward the victim. Analogue signals are collected through a single antenna and generally have a greater initial range, but require practice to pinpoint a signal within the final few meters of a search. They are suited to grid or induction search patterns.
• Digital beacons offer information in the form of a distance-to-the-victim, and direction-to-the-victim digital display. Collecting information using a dual antenna system and using digital signal processing allows accurately pinpoint the location of a buried individual and lets the user follow an arc or induction search pattern. The advantage to this is that the searcher follows the shortest possible line to the victim. They are particularly precise during a fine search, but may have a smaller initial range. Some digital beacons also convey information to help determine whether the search is a single or multiple person burial and allow you to filter out competing signals.

Neither type of beacon is inherently “better”, if you're buying a beacon, try out several models and select the one that you find easiest and most intuitive to use. More important than the type of beacon you own is your ability to use it.

Transceiver Compatibility

The same technology that makes some digital transceivers so accurate for precision searches may also create compatibility problems with other, older transceivers. Newer transceivers are designed to receive signals only on a very narrow bandwidth, tightly focused around the 457kHz frequency. This highly accurate tuning filters out extraneous noise and permits greater precision in the final phases of a search. But some older transceivers can become less precisely tuned. They may wander off-frequency over time. This situation can cause a transceiver to transmit in a range outside the “hearing” of a precision-tuned newer transceivers. (Some manufacturers deliberately make beacons less selective in their reception than is technologically possible; this wider reception ensures they won't miss slightly off-frequency signals. However, this accessibility reduces the initial search range.)

To avoid transceiver compatibility problems:

1. Have your transceiver factory serviced at the manufacturer's recommended interval (usually every three to five years) to keep it transmitting as closely as possible to 457kHz.
2. At the start of every trip, test that each participant's beacon can transmit to and receive from everyone else's beacon. (Even if two beacons were compatible in the past, one of them may have wandered off-frequency.) Having every traveller in tune with all of their fellow adventurers is essential to having the maximum number of effective searchers available in the event of an avalanche burial. The more searchers, the greater the chance of a successful rescue.

Probes

The only way to penetrate dense, compacted avalanche debris is to use a multi-sectioned aluminium pole called an avalanche probe. They extend two to three metres long, and are held in tension with a cable. When a searcher with a beacon has honed in on a buried person, other members of the party should probe the snowpack for the exact location of the victim. (You cannot pinpoint a person who is deeply buried using only a beacon.) The probe is left in contact with the victim until they have been exposed by shovelling.

Probes also have other uses, such as checking snowpack depth, and testing crevasse bridges and cornices while travelling. For this reason, they are currently carried by most travellers and are recommended over probe poles.

Shovels

Finding the location of a victim is only the first part of the rescue – digging them out is the second critical step. In the seconds after an avalanche, even fresh powder will solidify so densely that you cannot push your hand into it. There are many different types of avalanche shovels. The more high-tech models have telescoping handles that extend to give better leverage when shovelling. Metal blades chop debris better than lexan or polycarbonate, and the bigger the blade, the more snow you can move with each scoop. The important thing about shovels is that everybody in your group has one. It is also worth practising excavation in a team of two or three to learn to shovel effectively as a group.

Read more about Backcountry Safety.