Flame resistance test

In general, flame retardancy tests are categorized into two types: direct flame method and indirect flame method, as defined in the UL94 standard. The direct flame method involves applying a flame directly to a test piece mounted either vertically or horizontally under controlled conditions. On the other hand, the indirect flame method is characterized by the use of a non-flame heat source such as a nichrome wire, and the test is conducted by applying the red-hot wire to the test piece.