Thomas DiPietro, a research fellow at the Fire Safety Research Institute (FSRI), part of UL Research Institutes, found choosing a topic for his master’s thesis fairly easy. As a fire protection engineering student and an active firefighter, Thomas knew he wanted to investigate a topic related to firefighting or firefighter safety. After months of brainstorming, researching, and consulting with his advisors, Thomas decided to test the thermal properties of firefighter turnout gear. Aiming to expand previous FSRI research, this topic allowed a feasible way to do so.
While Thomas is part of FSRI’s fellowship program, he began his time at the organization as an intern. He quickly discovered a career path that combined his interests in firefighting and engineering. This experience prompted him to pursue his master’s degree in fire protection engineering at the University of Maryland, College Park (UMD). His team at FSRI encouraged him to apply for FSRI’s fellowship program, which supports UMD graduate students’ research assistantships.
Roughly two years later, on July 17, 2024, Thomas defended his thesis, a milestone that represented the end of his fellowship. His thesis, “Experimental Characterization of the Thermal Response of Firefighter Protective Ensembles Under Non-Flaming Convective Exposure,” explored the thermal response of three-layer firefighter turnout gear. The research focused on the turnout gear’s behavior when exposed to majority convection, low-level heat flux in an oven.
Experiments Explored The Thermal Response of Turnout Gear
Thomas conducted a series of experiments to measure the temperature beneath a firefighter’s turnout gear. To simulate firefighters’ skin, Thomas employed a copper calorimeter, a device that can measure the amount of heat absorbed or released. He positioned the copper calorimeter beneath two different protective ensembles. While each protective ensemble consisted of distinct materials based on different gear specifications, both sets consisted of an outer shell layer, moisture barrier layer, and thermal liner layer.
He then measured the temperature of the copper calorimeter while exposing it to temperatures of 100°C, 150°C, 200°C, 250°C, and 300°C. In the first set of experiments, Thomas controlled the heat through majority forced convection via an industrial oven. However, additional experiments were conducted using a radiant heat flux from a Controlled Atmosphere Pyrolysis Apparatus, as radiant heat is commonly used in turnout gear heat transfer research.
Throughout the series of experiments, Thomas recorded the time it took for the copper calorimeter to reach a temperature of 55°C, the point at which a second-degree burn could occur on human skin. He compared that value to currently accepted thermal operating time limits for firefighters.
Findings Demonstrated Reduced Safe Operational Times Above 100°C of Exposure
Results show that once exposure reached above 100°C while the PPE was in contact with the copper disk, the time for a potential burn injury to occur fell below the predicted safe operational time for firefighters of 15—20 minutes. Although protective ensembles consisted of different materials, both types responded similarly and demonstrated no significant differences in time to potential burn injury at every temperature. Future thermal response research should expand upon these findings to ensure safe operational periods for firefighters.
“Conducting research for my Master’s thesis through the FSRI Fellowship program has been an invaluable experience. The knowledge I gained from my studies and mentors prepared me to become a better engineer as I begin my career.”
—Thomas DiPietro, research fellow, FSRI
Thomas’s mentors were Charley Fleishmann, FSRI principal engineer, Keith Stakes, FSRI research engineer, and Dr. Fermanndo Raffan-Montoya, UMD assistant professor. Thomas earned his bachelor’s degree in mechanical engineering with a concentration in aerospace engineering from Rowan University in New Jersey in May 2022. As Thomas wraps up his graduate studies, he looks forward to beginning the next chapter of his fire protection engineering career.
The Fellowship Program is provided to incoming Master of Science students enrolled in the UMD Department of Fire Protection Engineering program and is awarded on a competitive basis. Research conducted through this program has allowed FSRI to sponsor work that expands upon current FSRI projects, such as the PPE Emerging Issues project. Over the years, many of our fellows have gone on to graduate and begin their careers at FSRI and other fire safety organizations.
