Full Description JIS T 8020:2020 specifies two complementary methods (Method A and Method B) for determining the behaviour of materials used for protective clothing against heat and fire subjected to heat radiation. These tests are carried out on representative single or multi-layer textiles or other materials intended for clothing for protection against radiant heat. They are also applicable to assemblies, which correspond to the overall build up of a heat protective clothing assembly with or without underclothing.