Richard - I have no direct evidence to support a claim either way, but if a material can only meet HB requirements, I have strong doubts about its ability to have a FS of 200, using ASTME84 test. The Steiner Tunnel testing uses a significantly different method from the 1/2 in. flame test used for HB testing. The burner configurations, amount of heat evolved from the burners and the sample size requirements make the two tests almost impossible to compare. It's like comparing a match stick to a bonfire.
This is not to say that some HB rated material might not be capable of garnering a FS=200. Some materials are rated HB, only because that's what the resin manufacturer requested to have the material tested for. It might possibly meet one or another vertical flame rating requirements, or even 5V, but if the resin manufacturer only requested HB, that's the best they'll get (this is based on my experience testing plastics and printed wiring boards during my tenure at UL), because they aren't interested in paying for vertical flame testing. Regards, Peter L. Tarver, PE ptar...@nortelnetworks.com -----Original Message----- From: wo...@sensormatic.com Sent: Friday, July 28, 2000 7:46 AM I have heard that HB flame rated plastics is considered compliant with the UL723 / ASTM E84 flame spread rating of 200. Doe anyone have any information on this? Richard Woods
