The ASTM E648 test is a standard of the American Society of Testing and Materials (ASTM) that measures the fire resistance of interior floor coverings that are exposed to a flaming ignition source in a graded radiant heat energy test chamber. This test simulates a scenario in which floor coverings within a corridor would be exposed to flames and radiant heat emanating from a fire in an adjacent space. Results obtained from this test are used by code officials in the acceptance of floorcoverings for a building corridor application.
The scope of testing involves mounting a test specimen horizontally to a concrete substrate on the floor of the test chamber. A gas-fired burner with multiple flamelets is ignited above one end of the test specimen and, after a preheat period, the multi-flamelet burner is lowered so that the flames touch the test specimen. The test is concluded when all burning of the specimen extinguishes, which is called the “critical radiant flux at flameout.” The test specimen is evaluated, and the distance of the burns are measured. The shorter burn distances receive higher critical radiant flux values, and higher values are considered better.
The results from the test are recorded and the specimen is classified according to two categories, with the rating of Class 1 being the most fire-resistant category.
Class 1: Minimum critical radiant flux at flameout of 0.45 watts/cm2
Class 2: Minimum critical radiant flux at flameout of 0.22 watts/cm2