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Samuel L. Manzello, Seul-Hyun Park, Sayaka S. Suzuki, John R. Shields, Yoshihiko Hayashi


The present investigation is aimed at extensively quantifying firebrand penetration through building vents using full scale tests that made use of the NIST Firebrand Generator (NIST Dragon) coupled to the Fire Research Wind Tunnel Facility (FRWTF) at the Building Research Institute (BRI) in Tsukuba, Japan. In these experiments, 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, ranging from 5.72 mm to 1.04 mm. 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. While full scale tests are necessary to highlight vulnerabilities of structures to firebrand showers, 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 for the first time. The newly developed facility is known as the NIST Dragon’s LAIR (Lofting and Ignition Research). The NIST Dragon’s 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 through the mesh opening, even down to 1.04 mm opening. The experiments demonstrate that mesh was not effective in reducing ignition for the fine fuels tested and firebrand resistant vent technologies are needed. The reduced scale Dragon’s LAIR facility was able to reproduce the results obtained from the full scale experiments.
Proceedings Title
Proceedings of the 2010 Interflam Conference
Conference Dates
July 5-7, 2010
Conference Location
Conference Title


Wildland-Urban Interface (WUI) Fires, Firebrands, Mesh


Manzello, S. , Park, S. , Suzuki, S. , Shields, J. and Hayashi, Y. (2010), QUANTIFYING WIND DRIVEN FIREBRAND PENETRATION INTO BUILDING VENTS USING FULL SCALE AND REDUDCED SCALE EXPERIMENTAL METHODS, Proceedings of the 2010 Interflam Conference, Nottingham, -1, [online], (Accessed February 27, 2024)
Created July 5, 2010, Updated February 19, 2017