Test method for evaluating fabric flammability and predicted skin burn injury in microgravity

To address fire safety concerns associated with the use of flammable fabrics during space travel, an apparatus was designed to be flown on low-gravity parabolic aircraft flights in order to assess the flammability of cotton and 50% cotton/50% polyester fabrics, and the resulting skin burn injury that would occur if these fabrics were to ignite. The apparatus, modelled after a standard fabric flammability test, was also used on the ground for experiments under earth’s gravity. Variables examined in the tests include gravity level, fabric type, air gap size, and orientation of the fabric. Flame spread rates, heat fluxes, and skin burn predictions determined from test results were compared under the two gravity levels. The orientation of the fabric had a large effect on flame spread rates, heat fluxes and predicted skin burn times for tests conducted under earth’s gravity. Flame spread rates and heat fluxes were highest when the fabric was held in the vertical orientation, which resulted in the lowest predicted times to produce skin burns. Flame spread rates and heat fluxes were considerably lower in microgravity than under earth’s gravity, which resulted in longer predicted times to produce skin burns.