This survey describes a series of ignition sources potentially applicable to assessing fire-test-response characteristics resulting from the ignition of electrical and electronic insulation materials or of electrical or electronic products containing such materials. This survey describes both flaming and non-flaming ignition sources, since the outcome of a non-flaming ignition can be the eventual flaming ignition of these materials or products. Non-flaming ignition sources include smoldering cigarettes, glow wires, hot wires and radiant heat sources. Radiant heat sources are often accompanied by a supplementary igniter, which can be a pilot flame. Flaming ignition sources include both premixed flames and diffusion flames. The overall characteristics of ignition sources being discussed include: 1. The intensity of the ignition source. This is a measure of the thermal insult onto the test specimen resulting from the combined conduction, convection and radiation effects caused by the ignition source. 2. The location of the impingement of the ignition source on the test specimen. 3. The duration of exposure of the test specimen and whether it is continuous or intermittent. 4. The orientation of the test specimen in relation to the ignition source. 5. The ventilation conditions in the vicinity of the ignition source and exposed surface of the test specimen. A variety of standard test methods, specifications and regulations have been issued (by organizations including ASTM, NFPA, ISO, IEC, IEEE, TJL and FAA) that contain ignition sources used for electrical and electronic insulation materials and the products in which they are used. This survey describes such ignition sources and includes information on the standard method in which they were first described.
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