Cool clothing for hot heads

Australian scientists have invented a new high tech vest to help keep soldiers and emergency workers alive in the searing heat experienced in deserts, mines and major fires.

The vest uses a personal cooling system (PCS), jointly developed by CSIRO Australia and the Australian Defence Science and Technology Organisation (DSTO).

It is designed to be worn by military personnel underneath nuclear, biological and chemical (NBC) clothing, body armour and other protective uniforms, by emergency services workers wearing protective clothing and by miners working underground.

A new NBC suit recently developed by DSTO, when worn with the Personal Cooling System, will allow soldiers to operate up to four hours in high temperatures, when previously only one hour was possible. During the Gulf War, troops could generally only last about 20 minutes in the NBC suits before they succumbed to heat stress.

Dr Pratish Bandopadhayay of CSIRO Thermal & Fluids Engineering said surrounding the body in protective clothing prevents cooling by normal sweat evaporation. This reduces the operational time protective clothing can be worn without greatly increasing the risk of injury.

‘The PCS is based on new, patented heat pipe technology which works by collecting body heat through vapour filled cavities in a vest worn on the body. The heat is then transferred via a flexible heat pipe to the atmosphere with the help of an evaporative cooling heat exchanger,’ said Dr Bandopadhayay.

‘The heat exchanger is similar in principle to a bush fridge where a cold cloth is put over a container and the temperature drop caused by evaporation keeps the food cool.

‘This concept has been demonstrated in a series of experiments conducted by DSTO researchers in which thermal strain has been greatly minimised in soldiers exercising in simulated military operations,’ he added.

On the web