Improving fire investigators’ understanding of fire patterns by increasing knowledge of fire behavior and the impact of ventilation on different fire scenarios
Knowledge of fire dynamics is critical for fire investigators to properly identify a fire’s origin. Fire dynamics depend on the relationship of the fuel, heat, and ventilation during a fire event. A ventilation change as simple as a door left open by an occupant fleeing the fire, a window open remote from the fire, or a window that fails as a result of fire growth could greatly impact the fire damage inside the structure.
- Improve investigators’ understanding of fire patterns by increasing knowledge of fire behavior and the impact of ventilation on different fire scenarios
- Develop knowledge of fire patterns within full-size modern residential homes, incorporating an open floor plan and two-story great room
- Identify and disseminate standard best practices for the use of fire damage and patterns resulting from ventilation during fire based on science
- Conduct fire modeling based on a series of full-scale fire experiments to further the linkage between modeling, fire ventilation and fire patterns
Full-scale testing was performed in representative models of modern single-family homes that incorporated modern construction practices.
Here’s why: over the past 30 years, home construction materials, contents, size and geometry have changed drastically—and consequently, so has fire behavior. Today’s fires, thriving as they do on predominantly synthetic materials, tend to become ventilation-limited. How and where a fire receives oxygen greatly impacts the fire dynamics and subsequent fire patterns.
Researchers performed three types of full-scale experiments over 40 days at UL’s Large Fire Lab in Northrbook, Illinois including:
- Ranch house (1200 sq. ft. single family, ranch-style house) experiments ranged from fires with no exterior ventilation, to room fires with flow paths that connected the fires with remote intake and exhaust vents throughout the structures. Elevated fires originating in a kitchen were also examined.
- Colonial house (3200 sq. ft. two-story colonial style house) experiments ranged from fires with no exterior ventilation, to room fires with flow paths that connected the fires with remote intake and exhaust vents throughout the structures. Elevated fires originating in a kitchen were also examined.
- Exposed electrical cord and cable experiments were designed to compare the thermal conditions that lead to failure of different energized cord and cable systems and the type of trip for different circuit breakers when exposed to flashover conditions. Eighteen configurations which consisted of 6 different cords and cables and 3 circuit breakers for each cord/cable type were installed in the floor at the ventilation opening.
RESOURCE #1: Impact of Ventilation on Fire Patterns Project Page
RESOURCE #2: Fire Investigation Data Portal
This research is led by UL's Fire Safety Research Institute with input from a technical panel comprised of national fire investigation experts that represent a range of forensic specialties in both the public, private, academic, and research sectors.
Award No. 2015-DN-BX-K052, awarded by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice.
Full-scale testing was performed to research how ventilation impacted fire patterns and electrical system damage in single-family homes.
Interactive Training Module Focuses on Fire Behavior and Impact of Ventilation on Residential Fire Damage Patterns
Understanding fire dynamics is essential to understanding fire damage patterns and identifying a fire’s area of origin based on the scientific method. Learn more and watch the video.
Peer-Reviewed Journal Article Examines the Impact of Flashover Fire Conditions on Exposed Electrical Cords and Cables
Research Engineer Craig Weinschenk and Director of Research Daniel Madrzykowski wrote a peer-reviewed journal article along fellow researchers that was published in Fire Technology.