BS 476-4:1970(AMD 1983) Fire tests in building materials and structures Part 4: Non-combustibility test for materials: This British Standard, a part of the BS 476 series, specifies a method of test for determining whether building materials are non-combustible within the meaning of the definition.
Materials used in the construction and finishing of buildings or structures are classified “non-combustible” or “combustible” according to their behaviour in the “non-combustibility test”.This test is intended for building materials, whether coated or not, but it is not intended to apply to the coating alone.