On April 12, 2009, a fire in a one-story ranch home in Texas claimed the lives of two fire fighters. Sustained high winds occurred during the incident. The winds caused a rapid change in the dynamics of the fire after the failure of a large section of glass in the rear of the house. At the request of the National Institute for Occupational Safety and Health (NIOSH) and the Houston Fire Department (HFD), NIST assisted with examining the fire dynamics of this incident. NIST performed computer simulations of the fire using the FDS and Smokeview, a visualization tool, to provide insight on the fire development and thermal conditions that may have existed in the residence during the fire.
The FDS simulation that best represents the witnessed fire conditions indicates that the critical event in this fire was the creation of a wind-driven flow path between the upwind side of the structure and the exit point on the downwind side of the structure, the front door. The flow path was created by the failure of a large span of windows in the den, in the rear of the structure. In a simulation that excluded wind, the thermal environment surrounding the location of interior operations was improved. Based on the analysis of this fire incident and results from previous studies, adjusting fire fighting tactics to account for wind conditions in structural fire fighting is critical to enhancing the safety and the effectiveness of fire fighters.
Still image from FDS simulation. Temperatures at 1.5 m (5 ft) above the floor throughout the house 10 s after solarium failure. Image credit: NIST.