What are the best products to use in installations where fire ratings are important?
Mats and grates with UltraSorb® strips, mats and grates with plain metal surfaces like eleGril® stainless steel grates, aluminum thin line grates and mats and grates with carpet tread are the most appropriate for use in installations where fire ratings are important.
What tests measure the performance of mats and grates in a fire?
The two most common tests for entrance mats and grates are the Optical Density of Smoke Generated by Solid Materials, ASTM E662-93 (NFPA 258) and the Critical Radiant Flux, ASTM E648-94 (NFPA 253 and FTM Standard 372).
What is ASTM E662-93?
The ASTM E662-93 Optical Density of Smoke Generated by Solid materials, also known as NFPA 258, is one of the most frequently requested fire tests for entrance matting.
The test involves using a photometric system to optically measure the density of smoke generated when a sample heated. Measurements are taken when the sample is in flaming mode (actually burning) and in non-flaming mode (with radiant heat but no flame). The smoke is measured on a scale of 1 to 1,000. There is no class rating, only pass or fail. To pass, smoke density must be below 450. Most nylon carpets pass this test. Carpets with vinyl backing often fail.
Arden Architectural's standard carpet and UltraSorb® both pass this test. Rugged Scrub®, a polypropylene product, does not. EnvIRONtread® buffed rubber treads do not pass this test either.
What is ASTM E648-94?
The ASTM E658-94, Critical Radiant Flex, is also referenced NFPA 253 and FTM Standard 372. This test measures the amount of heat (radiant energy) needed to keep a carpet flaming. The more energy needed to keep the carpet burning, the less likely the carpet will burn. Therefore, a higher number in the rating is better. There are two rating classes, Class 1 and Class 2. Class one includes ratings above .45 watts/square cm. Class 2 includes ratings between .22 and .45. Our UltraSorb has an average critical radiant flux of .53, making it Class 1. Our standard carpet is Class 2.
