Do test methods yield meaningful performance specifications

There is an urgent need for standards to evaluate the protection against intense heat afforded by textile materials. But there is equally a need to look carefully at where and how they should be applied. In most intense heat exposure accidents in which fires or explosions are involved, the bulk of the energy incident on the victim is in the form of radiant heat. Convective heat tests are subject to a number of problems that create uncertainty in the interpretation of test data, and in many instances, high-intensity radiation tests would provide the information required. The performance requirements for each application should be carefully considered. In some occupations, it is more important that other risks, such as heat exhaustion, be given higher priority in the setting of garment performance requirements. Protective clothing can reduce the risk of injury but cannot guard against all hazards. Where the test exposure exceeds about 10 kW/m 2 , a mandatory pass-fail screening, consisting of a simple mechanical rigidity assessment following exposure, should be included. This eliminates materials that maintain a rigid char until the moment deformation is applied. It is important not to misinterpret test results. Test methods are essentially a means of ranking performance, whereby the heat transfer of materials can be compared under similar conditions, and a measure of the degradation obtained under those conditions. They ought not to be regarded as duplicating real-life exposures.