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Summary of Full Scale Experiments to Determine Vulnerabilities of Building Components to Ignition by Firebrand Showers



Samuel L. Manzello, Sayaka S. Suzuki, Yoshihiko Hayashi


Wind driven firebrand showers are a major cause of structural ignition in Wildland-Urban Interface (WUI) fires in the USA and urban fires in Japan. For over 40 years, past firebrand studies have focused on understanding how far firebrands fly (spotting distance). These firebrand transport studies do not assess the vulnerabilities of structures to ignition from firebrand attack and are of limited use to develop ignition resistant structures. Building codes and standards are needed to guide construction of new structures in areas known to be prone to these fires in order to reduce the risk of structural ignition in the event of a firebrand attack. Proven, scientifically based retrofitting strategies are required for homes located in areas prone to such fires. To meet these objectives requires knowledge regarding the types of materials that can be ignited by firebrands as well as vulnerable points on a structure where firebrands may easily enter. In order to do this, a unique experimental apparatus, known as the NIST Firebrand Generator, has been constructed to generate controlled, repeatable firebrand showers commensurate to those measured from burning conifers and a real WUI fire. 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). This report brings together all of the full scale experimental results conducted by NIST using BRI’s FRWTF to date.
Special Publication (NIST SP) - 1126
Report Number


WUI Fires, Firebrands, Ignition


Manzello, S. , Suzuki, S. and Hayashi, Y. (2012), Summary of Full Scale Experiments to Determine Vulnerabilities of Building Components to Ignition by Firebrand Showers, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 14, 2024)


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Created January 2, 2012, Updated November 10, 2018