Flame retardancy test

In general, flame retardancy tests are classified into two methods, the direct flame method and the indirect flame method, as defined in the UL94 standard. The direct flame method involves applying a flame directly to a test specimen mounted vertically or horizontally under controlled conditions. In contrast, the indirect flame method is characterized by the use of a non-flame heat source such as a nichrome wire, where the test is conducted by applying the red-hot wire to the test specimen.