Determining Structure Vulnerabilities to Firebrand Showers in Wildland-Urban Interface (WUI) Fires
Samuel L. Manzello, Seul-Hyun Park, Sayaka S. Suzuki, John R. Shields, Yoshihiko Hayashi
Attempting to experimentally quantify the vulnerabilities of structures to ignition from firebrand showers has remained elusive. The coupling of a two unique facilities has begun to unravel this difficult problem. The NIST Firebrand Generator (NIST Dragon) is an experimental device than can generate a firebrand shower in a safe and repeatable fashion. Since wind plays a critical role in the spread of WUI fires in the USA and urban fires in Japan, NIST has established collaboration with the Building Research Institute (BRI) in Japan. BRI maintains one of the only full scale wind tunnel facilities in the world designed specifically for fire experimentation; the Fire Research Wind Tunnel Facility (FRWTF). The present investigation is aimed at extensively quantifying firebrand penetration through building vents using full scale tests. A structure was placed inside the FRWTF and firebrand showers were directed at the structure using the NIST Dragon. The structure was fitted with a generic building vent, consisting of only a frame fitted with a metal mesh. Six different mesh sizes openings were used for testing. Behind the mesh, four different materials were placed to ascertain whether the firebrands that were able to penetrate the building mesh assembly could ignite these materials. Reduced scale test methods afford the capability to test new vent technologies and may serve as the basis for new standard testing methodologies. As a result, a new experimental facility developed at NIST is presented and is known as the NIST Dragons LAIR (Lofting and Ignition Research). The NIST Dragons LAIR has been developed to simulate a wind driven firebrand attack at reduced scale. The facility consists of a reduced scale Firebrand Generator (Baby Dragon) coupled to a bench scale wind tunnel. The BRI/NIST full scale and NIST reduced scale experiments found that firebrands were not quenched by the presence of the mesh and would continue to burn until they were able to fit
, Park, S.
, Suzuki, S.
, Shields, J.
and Hayashi, Y.
Determining Structure Vulnerabilities to Firebrand Showers in Wildland-Urban Interface (WUI) Fires, Fire Safety Journal
(Accessed June 4, 2023)