Fire Dynamics for Fire Investigators
The Fire Safety Research Institute (FSRI), a part of the UL Research Institutes has conducted research examining the impact that changes in home construction materials, contents, size, and geometry have brought to residential structure fire growth and development. Needless to say, these changes in the built environment will impact the fire patterns that investigators will find. Today’s fires are predominantly fueled by synthetic contents and commonly become ventilation-limited. How and where the fire receives oxygen impacts the fire dynamics and subsequent fire patterns. This presentation will examine the current structural fire environment and the basics of fire dynamics, especially related to ventilation limited fires and flow paths. A section on flow paths has been added into the 2024 edition of NFPA 921. Data and videos from full-scale house experiments will be used to enable the understanding of the development of fire patterns relative to the changes in ventilation. The test structures include one-story ranch structures and two-story colonial structures. The colonial had a two-story family room and open foyer. The experiments were planned with the assistance of a technical panel that included members of ATF, IAAI, NAFI, NASFM, NIST, NIST OSAC, and NFPA 921. The test scenarios ranged from fires in the homes with no exterior ventilation, to room fires with flow paths that connected the fires with remote intake and exhaust vents throughout the structures. The impact of HVAC systems on fire development in homes will also be presented. Data from fires started with multi-cell battery modules going into thermal run away will also be presented to discuss the speed of fire growth and the potential for explosions. This presentation will also provide an overview of research results from ongoing research efforts. Featured results will include the recently released materials and products database and full-scale data repositories which are publicly available for use at no cost. Additionally, results from the post-fire exposure risks to fire investigators study and an example of a near miss analysis case will be shared.
