Space technology keeps its cool

A European Space Agency (ESA) funded project is applying space suit technology to safety clothing for firefighters, steel workers and other people who work in dangerously hot conditions.

The Safe&Cool project is developing a protective material with a built-in cooling system based on the technology developed for the space suits used by astronauts on the International Space Station to prevent them from overheating when exposed to direct sunlight during space walks.

The inability to shed excess heat and moisture can lead to heatstroke, which causes symptoms from loss of concentration through to serious illness and even death. Carrying out hard physical work in impermeable clothes adds greatly to the risk. 

The Safe&Cool system makes use of three special technologies. Firstly a special 3D-textile structure is used in the thermal and moisture management layer to replace the interliner and moisture barrier of classical three-layered protective clothing.

The materials used in the special 3D-textile structure are hydrophobic thermal comfort fibres to avoid a wet feeling when in contact with the body, combined with hydrophilic fibres to create suction channels to transport moisture away from the skin.

The second technology is the cooling apparatus derived from astronauts' suits. This enables liquid to be circulated through tubing inserted in cavities in the 3D-textile structure for heat removal. A water-binding polymer is the third technology and this will be added either as a coating or in the form of a powder dispersed inside the fabrics.

The polymer will absorb and bind excess moisture migrating through the semi-permeable membrane to maintain the temperature below a threshold controlled by the cooling apparatus. If there is a sudden temperature increase, arising from a burn flashover for example, and the cooling system cannot remove heat fast enough from the body, the polymer will release the liquid accumulated, reproducing the human natural sweating process through evaporative cooling.

The cooling apparatus used in the project has already been used successfully in clothing for Formula-1 McLaren mechanics and the Spanish Moto-GP driver, Sete Gibernau.