Avalanches are one of the biggest threats to everyone that takes on the snow-capped peaks, be it while snow skiing, snowboarding or hiking. No one wants to entertain the thought of being buried under meters of snow, so to be prepared for an avalanche, is the best defense. Carrying an avalanche beacon while on the slopes is vital for survival and for rescue. Technological advances have improved avalanche beacons and made them easier to use. It is a piece of equipment that could prove life-saving after an avalanche has dealt its potentially deadly blow.
The first form of avalanche beacons were developed by Dr. John Lawton in the year 1968. It was a simple device that used a frequency 2.275 kHz, audible to the human ear, which sent out a tone for the rescue team to follow. The closer the team moved towards the victim, the louder the tone would get. Today, the required frequency is 457 kHz, and the avalanche beacons have become smaller, compact and light.
To start, there are digital and analog avalanche beacons available. Both are commonly used, with the user deciding which device they are more comfortable with. An analog avalanche beacon, works in a similar way to the one Dr. Lawton designed. Together with a visual display, the beacon also transmits an audible signal, getting stronger when nearing the beacon. The signal that is transmitted from the beacon with a single antenna is referred to as the flux line. Digital beacons use multiple antennae, making use of a microprocessor to send vital information such as direction and distance, through its flux line. An audible signal is also transmitted, as with the analog beacons. Although digital beacons are more user-friendly, many still prefer the analog beacon as its battery life is longer than the digital, giving searchers and rescue teams more time to find the victim and most searchers find the real time signal much more accurate during a rescue. Some of the latest technologies have now combined the features of both avalanche beacons to improve rescue times and ensure that they are simple to use.
During rescues, searchers use the flux line to locate the avalanche beacon. The flux line is the electromagnetic signal that is sent out by the beacon. It refers to the way the signal is sent. Most transmitters send out an outward signal at equal strength, while a flux line signal is sent in a three dimensional pattern. Rescue teams train rigorously to be able to conduct induction searches, circle method searches and grid searches, with as much speed and accuracy as possible. Search methods are adjusted according to the situation and scenarios are practiced to provide victims with the best search and rescue effort possible.
When snowboarding or skiing, or simply exploring the mountains on foot or by snowmobile, it is recommended to wear an avalanche beacon at all times. They could safe a life, as avalanches never give warnings before they strike.