EFFECT OF SIDING TREATMENT ON FIREBRAND PRODUCTION FROM BUILDING COMPONENTS

摘要

Wildfires which spread into a community, commonly known as Wildland-Urban Interfacern(WUI) fires, is a significant problem all over the world. Post-fire investigations have demonstrated thatrnfirebrands are the major cause of structure ignitions. Yet, few studies on firebrand production, as wellrnas its ignition, have been conducted as most firebrand research has focused on its transport. In order tornunderstand the mechanism of WUI fire spread and growth, it is necessary to understand firebrandrnproduction both from vegetation and structures. To this end, firebrand production from real-scalernbuilding components under well-controlled laboratory conditions was investigated. Re-entrant cornerrnassemblies were ignited and during the combustion process, firebrands were collected to determine thernsize/mass distribution generated from such real-scale building components under varying wind speed.rnIn prior work, a unique ignition methodology was developed to generate firebrands from re-entrantrncorner assemblies constructed of wood studs and oriented strand board (OSB). In this study, thisrnignition methodology was applied to re-entrant corners constructed from wood studs/OSB but fittedrnwith actual siding treatments (tar paper and cedar siding) to determine the influence of sidingrntreatments on firebrand generation from wall assemblies. Firebrands were collected with pans filledrnwith water, and then the size and mass of firebrands were measured after drying. The size and massrndistributions of firebrands collected in this study were compared with the data from prior componentrntests as well as the limited studies available in the literature on this topic. Some firebrands were foundrnto be lighter for a given projected area than others, likely produced from cedar siding or tar paper. Therneffects of applied siding treatments on firebrand production will be discussed in more detail.