UL Fire Safety
Research Institute
Ranch House Experiments
To study how ventilation impacts fire damage and fire patterns in single family homes, experiments were conducted in a 1200 sq. ft ranch style house. The 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 Experiments
To study how ventilation impacts fire damage and fire patterns in single family homes, experiments were conducted in a 3200 sq. ft. two-story colonial style house. The 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
These 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.
Compartment Fire Dynamics Experiments
The purpose of the experiments is to close the knowledge gap concerning the use of fire dynamics analysis techniques which were developed with, and/or validated with, gas burner or liquid fuel pool fires by examining the applicability of these tools when actual furniture items are burned. A sense of the uncertainties involved in both the measurements and the analytical models is provided.
About The Research
Impact of Fixed Ventilation on Fire Damage Patterns
(NIJ Award No. 2015-DN-BX-K052)
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. FSRI’s fire investigation project completed scientific research into how ventilation impacted fire patterns and electrical system damage in single-family homes.
During the past decade, research conducted for the purpose of examining firefighting tactics has brought focus to the impact that on-going changes in home construction materials, contents, size, and geometry have on a fire incident. Current residential structure fires are predominantly fueled by synthetic contents and commonly become ventilation-limited. How and where the fire receives oxygen, especially with a ventilation-limited fire, impacts the fire growth. This project explored both the subsequent fire damage patterns and exposure of energized electrical cords.
Key Objectives:
1
To examine how differences in ventilation to full-scale structure fires result in changes to the fire damage and fire patterns within the structure.
2
To measure the fire environment within the structures and compare the data with the fire damage in the structures.
3
To document the repeatability or lack thereof of the fire conditions and fire patterns within a structure based on the available ventilation.
4
To provide a discussion of basic fire dynamics in structures, specifically regarding the impact of ventilation on the resulting fire patterns.
Examination of the Use of Fire Dynamics Analysis Techniques With Furniture Fueled Fires
(NIJ Award No. 2017-DN-BX-0163)
Computational models are increasingly relied upon in fire investigations, as part of the scientific method, to analyze data or to test hypotheses. The models can be used to qualitatively to gain insight on fire phenomena or fire-induced fluid flows. The models can also be used for quantitative analysis if an appropriate range of uncertainty is included. Model results, much like measurements, have varying degrees of uncertainty that can be affected as much by limitations of the model as well as unknowns in the model input parameters.
Understanding of the limitations, accuracy, and inherent uncertainties in each model is primarily based on fire measurements generated with well-characterized and, in many cases, steady-state heat sources, such as natural gas-fueled burners or liquid hydrocarbon pool fires. However in practice, the fires that are investigated are often fueled by natural and synthetic solid materials. These fuels are three-dimensional (as opposed to a two-dimensional burner surface), and the foam plastics used in furnishings tend to drip and flow during burning. Fires with these fuels are characterized by non-steady burning where rapid transitions in energy and fuel output are possible.
Key Objectives:
1
Evaluate the repeatability of key test measures associated with fire dynamics analysis such as heat release rate (HRR), heat flux, gas velocity, oxygen concentrations, and temperature.
2
Assess the accuracy of a range of predictive fire algorithms and models based on a fire in a compartment. The fires in the compartment were fueled by a natural gas burner or a piece of upholstered furniture. The model results were compared to the compartment fire test results.
Project Partners
This research was supported by Award Nos. 2015-DN-BX-K052 and 2017-DN-BX-O163, awarded by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice. The opinions, findings, and conclusions or recommendations expressed in this publication / program / exhibition are those of the author(s) and do not necessarily reflect those of the Department of Justice.
UL FSRI assembled a technical panel of national fire investigation experts that represent a range of forensic specialties in both the public, private, academic, and research sectors to guide the fire pattern and electrical research in support of the Impact of Fixed Ventilation on Fire Damage Patterns project.
Click here to see the project technical panel.Training
Impact of Ventilation on Fire PatternsIntroduction to Heat Transfer and Fire Measurements
UL Xplorlabs -- Fire Forensics: Claims and Evidence
Reports
Impact of Flashover Fire Conditions on Exposed Energized Electrical Cords and CablesImpact of Fixed Ventilation on Fire Damage Patterns in Full-Scale Structures
Modeling Gas Burner Fires In Ranch and Colonial Style Structures
Examination of Fire Dynamics Analysis Techniques: Assessment of Predictive Fire Algorithms and Models