|Tests in SINTEF’s laboratory basin show that the smart helicopter survival suits offers good protection against loss of heat when the wearer is in the sea. Photo: SINTEF Health Research|
Thanks to a cooperative project between these two partners offshore platform personnel on the Norwegian continental shelf have been issued with – literally – smart helicopter survival suits.
These offshore workers are among the first people in the world who can go to work in clothes with built-in intelligence.
The new suit has already aroused the interest of design experts.
The partnership is one of the recipients of the 2008 Good Design Mark, an award given by the Norwegian Design Council.
Combined helicopter and survival suit
Ever since the “Oil Age” came to Norway, platform workers have been easily recognisable in the heliports at Norwegian airports as they troop out to waiting helicopters in bright orange suits that will keep them from either drowning or freezing to death in the event of an emergency landing or a helicopter crash-landing at sea.
Now this group of workers is in the process of putting on a new generation of colourful suits. Thanks to their special qualities, the garments can be used both during helicopter transport and as survival suits out on the platform.
Not satisfied with what was available
The smart suits were developed in response to new demands made on behalf of the Norwegian Oil Industry Association (OLF).
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 Norwegian offshore oil-fields.
This initiative was enthusiastically received by the trade unions involved. The working group documented that users were dissatisfied with several aspects of the suits then in use.
The offshore workers felt that they were being “boiled alive” in the helicopters on warm summer days. At the same time, they feared that the original suits did not offer complete protection against heat loss during long periods in cold seawater.
The working group gained acceptance of their viewpoint that the helicopter suits must solve both of these problems in order to be approved.
Norwegian scientists and industry people have now demonstrated that what seemed to be conflicting requirements for cooling and heat insulation can be met.
The Norwegian clothing manufacturer Helly Hansen immediately started work on developing a new helicopter suit that would include solutions for all the new items on the long list of specifications.
Among other points, these innovations covered protection against spray on the face, 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.
Helly Hansen also gave SINTEF the task of developing solutions for cooling and heat insulation, based on SINTEF's work on SmartWear technology
“Smart use of functional textiles can give clothes completely new properties. In our work on the helicopter suit, we have made use of our knowledge of how heat and cold affect the human body, and how smart textiles can work in the same direction as the body's own reactions to cooling and heating”, explains research director Randi Eidsmo Reinertsen of SINTEF Health Research who is also a professor of physiology at the Norwegian University of Science and Technology.
Paraffin wax spheres
A core component of the new Norwegian helicopter suit is a commercially available textile that contains tiny in-woven capsules. These are filled with microscopic particles that consist 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.
“Melting requires heat, which the wax takes from the body, cooling the wearer in the helicopter cabin on warm days”, explain product designers Kristine Holbø and Jarl Reitan of SINTEF Health Research.
“In the laboratory, we have demonstrated that the skin temperature of the wearers does not rise by much. 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 time” says senior scientist Hilde Færevik, also of SINTEF Health Research.
An analogy from everyday life is a glass of water with ice-cubes. Until all the ice has melted, the water in the glass remains at the melting temperature of ice, i.e. zero degrees Celsius. Only when all the ice has thawed will the temperature of the water begin to rise.
The laboratory studies also showed that the subjects felt much more comfortable in the new suits than the old ones.
Protection against heat loss
At the same time, Færevik and her colleagues at SINTEF have documented that the new suit offers good protection against loss of heat when the wearer is in the sea.
“We believe that this is both because the paraffin wax releases the stored heat as it returns to the solid state, and because the suit contains extra insulation at the places where the body releases most heat,” she explains.
Important for survival
The suit ensures that the skin temperature of the wearer never falls below 15 degrees anywhere on the body in the course of six hours in water at a temperature of two degrees Celsius.
This ensures, for example, that helicopter passengers retain their ability to grasp things during long involuntary stays in the sea.
Warm hands and feet also ensure that heat is evenly distributed to all parts of the body, which is important for survival and for the ability to make a contribution to one's own rescue.
Not like the Michelin Man
“Critical voices claimed that the new requirements would make the suits too bulky, but by intelligent distribution of the insulation, we have avoided that they take up too much room”, explains Jarl Reitan.
In tough competition with recently developed clothing from foreign manufacturers, the Norwegian suit was victorious in a call for tenders from StatoilHydro, the first oil company to swap its old helicopter suits for the new variety.
SmartWear - a SINTEF Group area of special effort
SmartWear is one of six SINTEF Group areas of special effort. The aim of the programme is to develop two types of smart clothing:
Clothing with integrated instrumentation, i.e. with in-built sensors and communication equipment.
Clothing made of functional materials, i.e. materials that give them new properties in the event of changes in temperature or other aspects of the environment in which users find themselves.
These are multidisciplinary efforts, in which SINTEF researchers in information and communications technology, materials science, physiology and product design collaborate across disciplinary boundaries.