The loss of life in the tragic incident on Saturday morning at Siachen Glacier has left numerous families shocked and speechless. The avalanche smashed, probably at the time when soldiers were sleeping, and buried alive around 135 army personnel.

An avalanche occurs when a mass of snow falls down a mountainside. That is because new snow (which is not wet) accumulates on a more heavy snow layer. Since the new snow layer is not compact, it could slide down towards the base of the mountain. Avalanches could be triggered by loud noise like, firearm shots, etc.

According to Wikipedia, different tools and methodology can be applied for rescuing people stuck in avalanche. Recently, a device called an Avalung has been introduced for use in avalanche terrain. The device consists of a mouth piece, a flap valve, an exhaust pipe, and an air collector. Several models of Avalung either mount on one’s chest or integrate in a proprietary backpack.

During an avalanche burial, victims usually suffer from asphyxiation as the snow around them melts from the heat of the victim’s breath and then refreezes, disallowing oxygen flow to the victim and allowing toxic levels of CO2 to accumulate. The Avalung ameliorates this situation by drawing breath over a large surface area in front and pushing the warm exhaled carbondioxide behind. This buys additional time for rescuers to dig the victim out. Similarly, avalanche airbags help a person avoid burial by forcing the person towards the surface. Avalanche airbags work on the principle of inverse segregation. ]Avalanches, like mixed nuts and breakfast cereal are considered granular materials and behave fluid-like (but are not liquids) where smaller particles settle to the bottom of the flow and larger particles rise to the top. Provided the airbag is properly deployed, the chances of a complete burial are significantly reduced.

IFTIKHAR MIRZA,

ISLAMABAD, April 7.