Waxy fabric makes helicopter trips more comfortable
Norwegian oil workers will be the first to benefit from a smart suit that uses wax beads to keep the wearer cool in a stuffy helicopter cabin, but becomes heat retaining if an accident plunges them into cold seas.
The garment is made from a commercially available textile that is woven to incorporate tiny capsules filled with microscopic particles of a specially developed type of paraffin wax. If the skin temperature of the wearer of the clothing rises above 28 degrees Celsius, the wax changes phase from solid to liquid.
The design, which has already won an order from oil company StatoilHydro, was jointly developed by the SINTEF Norwegian research institute and specialist textile manufacturer Helly Hansen in response to appeals from the Norwegian Oil Industry Association.
In 2000, OLF appointed a working group to define the properties that helicopter suits should have in the future to be approved for use during transport to and from offshore oil-fields.
At that time, workers felt they were being ̶0;boiled alive̶1; on warm summer days, but feared that existing suits did not offer complete protection against heat loss during long periods in cold seawater.
The woven-in capsules help to provide a solution to both problems. Melting requires heat, which the wax takes from the body, cooling the wearer in the helicopter cabin on warm days. ̶0;In the laboratory, we have demonstrated that the skin temperature of the wearers does not rise by much,̶1; said SINTEF senior scientist Hilde Færevik. ̶0;We registered that our test subjects did not begin to sweat until as long as 80 minutes at an air temperature of 27 degrees, because the melting process actually lasts such a long time̶1;.
At the same time, the suit offers protection against loss of heat when the wearer is in the sea, with the paraffin wax releasing the stored heat as it returns to the solid state. Extra insulation at the places where the body releases most heat means that the skin temperature of the wearer should never fall below 15 degrees even after six hours in water at a temperature of two degrees Celsius.
Other features include protection against spray on the face, different sizes for large and small individuals, a breathing lung, emergency beacon and the ability to turn the wearer the right way up in the sea.
Image: The new suits include a range of features