Wind Driven Fires

A million dollar Baltimore County, Maryland  home was destroyed Sunday December 13, 2009  by a fire that tore through the 4,700-square-foot structure with such intensity that firefighters were forced to battle the flames from the exterior. Shortly after 21:00 hours, Baltimore County Fire Dispatch alerted crews for Fire Box 50-2 at 12607 Nancy Lee Court in the Worthington Trace subdivision in the Chestnut Ridge area. As firefighters were responding, dispatch advised they were receiving multiple calls to 911, with some reporting the entire house was on fire. While en route to the scene, Chestnut Ridge Volunteer Fire Company Captain Dan Uddeme reported heavy fire was visible and requested a 2nd alarm and a Tanker Strike Team as the house sits in an area without fire hydrants. Upon arrival, Capt. Uddeme reported fire had consumed the entire 2nd floor and roof area and was spreading.

Firefighters were forced to use exterior operations due to the heavy volume of fire. Responding units set up for rural water operations, shuttling more than 17,000 gallons of water from an underground tank on Greenspring Avenue and Walnut Avenue near the scene. Reisterstown Volunteer Fire Companys Engine 412 was also utilized for its Compressed Air Foam System, with several handlines and the ladder pipe from Glyndon Volunteers Truck 404 flowing foam. The Baltimore County Fire Investigation Division is investigating to determine the fires cause and origin. Video and data was obtained from Michael Schwartzberg’s Firepix1075 . Additional photos, HERE and newsreports, HERE

While watching the video, take the time to listen to the wind howling across the mic and observe the intesity level of the fire severity and propogation in the Charlie side. This provides an opportunity for those that are not familiar with the NIST Wind Driven Fire Studies or the PWC (VA) Kyle Wilson LODD to take some time to read about the affects of wind on incident operations, strategies and tactical personnel safety. This was a 4,700 SF large volume residential structure. Think about the performance and your deparment’s capabilities? Remember, it’s not “just” a house fire

Take a look at the Prince William County (VA) Fire & Rescue case study information related to Technician I Kyle Wilson – LODD Report. This event: Technician Kyle Wilson died in the line of duty on April 16, 2007 while performing search and rescue operations at a house fire on Marsh Overlook Drive, located in the Woodbridge area of Prince William County. On that day, Technician Wilson was part of the firefighter staffing on Tower 512 which responded to the house fire that was dispatched at 0603 hours. The Prince William County area was under a high wind advisory as a nor’eastern storm moved through the area. Sustained winds of 25 mph with gusts up to 48 mph were prevalent in the area at the time of the fire dispatch to Marsh Overlook Drive. Initial arriving units reported heavy fire on the exterior of two sides of the single family house and crews suspected that the occupants were still inside the house sleeping because of the early morning hour. A search of the upstairs bedroom commenced for the possible victims. A rapid and catastrophic change of fire and smoke conditions occurred in the interior of the house within minutes of Tower 512’s crew entering the structure. Technician Wilson became trapped and was unable to locate an immediate exit out of the hostile environment. Mayday radio transmissions were made by crews and by Technician Kyle Wilson of the life-threatening situation. Valiant and repeated rescue attempts to locate and remove Technician Wilson were made by the firefighting crews during extreme fire, heat and smoke conditions. Firefighters were forced from the structure as the house began to collapse on them and intense fire, heat and smoke conditions developed. Technician Wilson succumbed to the fire and the cause of death was reported by the medical examiner to be thermal and inhalation injuries.

• LODD Report Fact Sheet (29.3 kb)
• LODD Investigative Report (9.16 mb)
• LODD Report Presentation (6.65 mb)
• LODD Report Basic House Model (Section 1) (1.87 mb)
• LODD Report Fire Model (Section 3) (5.16 mb)
• LODD Flashover Chart (60 kb)

 National Institute of Standards and Technology – NIST Wind Driven Fire Research HERE Smoke and heat spreading through the corridors and the stairs of a building during a fire can limit building occupants’ ability to escape and can limit fire fighters’ ability to rescue them.  Changes in the building’s ventilation or presence of an external wind can increase the energy release of the fire.  This can also increase the spread of fire gases through the building.  In some cases, such as the Cook County Administration Building fire in October 2003, the fire gas flow, into the corridors and the stairway prevented fire fighters from suppressing the fire from inside the structure.  This fire resulted in 6 building occupant fatalities and fire fighter injuries in the stairway.  The Fire Department of New York City has experienced many wind driven fire incidents which have resulted in fire fighter fatalities and injuries.

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, such as single family homes, to control the fire flow by introducing pressure from the front door and venting the house through a strategic exit opening.  If done correctly, this tactic can remove significant amounts of heat and smoke from the structure, thus improving the fire fighters’ working environment and improving the chances of survival for the building occupants.  NIST has completed several studies which have a two fold impact: 1) providing guidance on the safe use of PPV and 2) characterizing and validating the modeling of PPV with a computational fluid dynamics (CFD) computer model, so that the model can be used as a training tool for the fire service. Fire Chief Magazine article HERE