1.1 This test method covers a laboratory procedure to determine the hot-surface ignition temperature of dust layers, that is, measuring the minimum temperature at which a dust layer will self-heat. The test consists of a dust layer heated on a hot plate.1.2 Data obtained from this test method provide a relative measure of the hot-surface ignition temperature of a dust layer.1.3 This test method should be used to measure and describe the properties of materials in response to hea