NFPA Research Report
Large structures, such as high rise buildings, have additional challenges for fire fighters and
building occupant safety such as increased travel distance (exposure time), more complicatedegress path, and potentially larger fires. Most notably, changes in the building’s ventilation or presence of an external wind, especially in high-rise buildings, can increase the energy release of the fire. This can also increase the spread of fire gases through the building. What tactics or tools are appropriate for use with a wind driven fire and how should the tactics or tools be implemented? Positive Pressure Ventilation (PPV) is being used by fire departments on smaller structures, and if done correctly, this tactic can remove significant amounts of heat and smoke from the structure. However the question remains as to whether these PPV fans can be used successfully under wind driven fire conditions in large structures? Other tactics incorporating devices, such as fire window blankets or smoke curtains to control the ventilation conditions or the use of a special fire nozzle from the floor below the fire floor have been tried by the fire service under “real fire” conditions with varying levels of success. Unfortunately, there is no data to understand the capabilities and limitations of these fire fighting approaches.

This project provided real-scale data to guide the development of appropriate tactical options for use under wind driven conditions. The goal is to improve the safety of fire fighters and building occupants by enabling a better understanding of wind driven firefighting tactics, including structural ventilation and suppression. The technical information resulting from this study contributes to our understanding of the dynamics of fire phenomena and prediction of fire intensity and growth under wind driven conditions. This data provides a basis to identify methods and promulgate improved Standard Operating Guidelines (SOG) for the fire service to enhance firefighter safety, fire ground operations, and use of equipment.

The National Institute of Standards and Technology, with the support of the Fire Protection Research Foundation and the U.S. Fire Administration conducted eight fire experiments to examine the impact of wind on fire spread through a multiroom structure and examine the capabilities of wind-control devices (WCD) and externally applied water to mitigate the
hazard. The measurements used to examine the impact of the WCDs and the external water application tactics were heat release rate, temperature, heat flux, and gas velocity inside the structure. Measurements of oxygen, carbon dioxide, carbon monoxide, total hydrocarbons and differential pressures were also measured.

Each of the experiments was recorded with video and thermal imaging cameras. The experiments were designed to expose a public corridor area to a wind driven, post-flashover apartment fire. The door from the apartment to the corridor was open for each of the experiments. The conditions in the corridor were of
critical importance because that is the portion of the building that firefighters would use to approach the fire apartment or that occupants from an adjoining apartment would use to exit the building.

The laboratory tests that NIST and the Fire Protection Research Foundation conducted are described in NIST Technical Note 1618, “Fire Fighting Tactics Under Wind Driven ...

The field study, in which NIST teamed with the Fire Department of New York City and the Polytechnic Institute of New York University, is reported in NIST Technical Note 1629 “Fire Fighting Tactics Under Wind Drive Fi... (http://fire.nist.gov/bfrlpubs/fire09/PDF/f09015.pdf).

Both projects were supported by the Department of Homeland Security’s Federal Emergency Management Agency Assistance to Firefighter Research and Development Grant Program and the United States Fire Administration.

A double DVD set on the research is available for teaching purposes. It includes a video overview, both reports, a PowerPoint presentation summarizing the results, training videos, and video documentation of all of the experiments. The information is available at www.fire.gov. The DVD set can be ordered by emailing a request to madrzy@nist.gov.