Wind's impact on structure fires studied

WASHINGTON, Feb. 8 (UPI) -- Wind conditions at a fire scene can change the behavior of the blaze and impact the safety of firefighters, even indoors, a U.S. government report says.

The National Institute of Standards and Technology said the findings are based on detailed computer models of a 2009 house fire in Houston that claimed the lives of two firefighters.

Two NIST fire experts traveled to Houston shortly after the April 2009 fire in a one-story ranch-style home to examine the site and collect data about factors that impact the behavior of the fire -- in particular, the wind at the time -- in order to understand the events that led to the deaths of a 29-year veteran captain and a probationary firefighter.

The computer models showed the fire followed a wind-driven flow path between the den and the front door of the home after the failure of a large span of windows in the den, with temperatures in excess of 500 degrees in the flow path where multiple crews of firefighters were working.

In another computer model that excluded wind, the flow path was not created and temperatures and conditions where the firefighters were working were significantly less hazardous, an NIST release said Wednesday.

"The 'wind' and 'no wind' simulations clearly demonstrate how wind conditions can rapidly change the thermal environment from tenable (survivable) to untenable for firefighters working in a single-story residential structure fire," NIST researchers said.

The findings highlight the importance of including wind condition factors in all structural firefighting operations and adjusting tactics according to changing wind situations, especially in indoor operations, to enhance the safety of firefighters, they said.