Changes phase - The new survival suit, which was been developed to accommodate the extreme environmental changes required by the Norwegian crews being transported to the oil platform. “From a production perspective, people claimed that it was impossible to meet the conflicting requirements for cooling and heat insulation in the same suit,” says Research Director Randi Reinertsen, a Professor of Physiology at SINTEF and head of the working group that developed the new survival suit.

“We utilized a textile that can change phase and made use of our knowledge about how cold and heat affect the human body. This enabled us to develop a suit that works in tandem with the body’s own reactions to cooling and heating.”

In-woven capsules – The technology utilized within the survival suit is a textile containing tiny in-woven capsules. This material can handle the extreme cooling and heating required. The capsules are made with tiny particles that contain a specially developed type of paraffin wax. If the survival suits occupant temperature rises above a predetermine level, the wax changes state from solid to liquid.

“Melting requires heat, which the paraffin wax takes from the body and cools the wearer in the helicopter cabin on hot days”, says Reinertsen. “On the other hand, if the person ends up in the sea, the paraffin wax changes phase and returns to a solid state, enabling the suit to return the stored heat back to the body.”

To understand the thermodynamics of the paraffin wax, visualize a glass of water containing ice cubes. As the ice has melts, the water will main an approximate temperature a little above the freezing point of the ice. The temperature of the water/ice mixture will remain at this temperature until all of the ice has melted.

“The findings show the textile keeps the suit wearer satisfactorily warm and comfortable for up to six hours in difficult conditions in the sea,” says Reinertsen.
That can mean the difference between life and death.