facts on flammability

Slide 14 of 37

A large number of component tests have been developed to screen the open flame performance of components for various end uses. None of these address the fact that materials in combination with other materials will perform differently than they do by themselves. The tests differ in terms of sample size, orientation (horizontal or vertical), intensity of the open flame, and performance criteria. And although it is generally assumed a vertical ignition test is more demanding than horizontal, this is not always the case. You cannot assume because a product passes a vertical flame test that it will survive a horizontal burn test.

Probably the most common open flame component test is California TB117, which uses a vertical orientation, bottom ignition and criterion for time of burning after ignition and maximum burn damage. And while this test often shows a difference between conventional FPF and combustion modified products, the difference may be much smaller or non existent in larger scale composite tests with larger ignition sources under conditions imposing higher ambient temperatures and more significant heat rise.

Other open flame component tests include MVSS 302, a horizontal open flame test uses to evaluate the materials used in the passenger compartment of automobiles. UL 94 is the Underwriter’s Laboratory test for materials that come in contact with electrical equipment and includes horizontal testing of a thin sample before and after accelerated aging. The flooring radiant panel test (ASTM E-948) for carpets and carpet cushion is an example of a test that evaluates extent and rate of flame spread with a sample that is exposed to a radiant heat source varying in intensity along the length of the sample. It is well recognized that the performance of carpet alone will not predict the performance of the same carpet with an insulating layer beneath it such as carpet cushion.