Presentation Type

Poster

Faculty Mentor’s Full Name

Lu Hu

Faculty Mentor’s Department

Department of Chemistry and Biochemistry

Abstract

Air pollutants from forest fires, including particulate matter and volatile organic compounds (VOCs), are harmful to humans and vegetation. Fire retardant mixtures are widely used to extinguish forest fires by aerial application, which may in turn affect the chemical component of fire smoke. Forest fire retardant includes a viscous solution of diammonium phosphate and color agents; once heated, it is expected to emit various toxic gases including ammonia and VOCs, precursors of particulate matter and ground-level ozone. This study examines the chemical components in toxic air emitted by fire retardant in controlled conditions to estimate their impact on air quality. I conducted laboratory experiments by burning three sets of materials: 1) the widely-used fire retardant only, 2) ponderosa pine needles only, and 3) fire retardant and pine needles combined. I examined the difference in the chemicals from the smoke of each burn, and I detected and analyzed VOCs and carbon dioxide (CO2) using a Proton Transfer Reaction – Mass Spectrometer and LI-COR CO2 analyzer. I calculated emission factors (g/kg) for each compound to estimate the mass of compound emitted per mass of dry fuel burned. I found most VOC compounds from burning both fire retardant and pine needles show an increase in the emission factor compared with burning pine needles alone. Significant amount of ammonia is also emitted when fire retardant is burned. Emission factors determined from the burn experiments are extrapolated to estimate the quantity of VOC and ammonia emissions from the Bitterroot-Lolo National Forest fire in 2016 to understand how fire retardant contributes to air pollution emissions.

Category

Physical Sciences

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Apr 17th, 11:00 AM Apr 17th, 12:00 PM

Laboratory Characterization of Toxic Air Emission from Fire Retardant Used in Wildfires

UC South Ballroom

Air pollutants from forest fires, including particulate matter and volatile organic compounds (VOCs), are harmful to humans and vegetation. Fire retardant mixtures are widely used to extinguish forest fires by aerial application, which may in turn affect the chemical component of fire smoke. Forest fire retardant includes a viscous solution of diammonium phosphate and color agents; once heated, it is expected to emit various toxic gases including ammonia and VOCs, precursors of particulate matter and ground-level ozone. This study examines the chemical components in toxic air emitted by fire retardant in controlled conditions to estimate their impact on air quality. I conducted laboratory experiments by burning three sets of materials: 1) the widely-used fire retardant only, 2) ponderosa pine needles only, and 3) fire retardant and pine needles combined. I examined the difference in the chemicals from the smoke of each burn, and I detected and analyzed VOCs and carbon dioxide (CO2) using a Proton Transfer Reaction – Mass Spectrometer and LI-COR CO2 analyzer. I calculated emission factors (g/kg) for each compound to estimate the mass of compound emitted per mass of dry fuel burned. I found most VOC compounds from burning both fire retardant and pine needles show an increase in the emission factor compared with burning pine needles alone. Significant amount of ammonia is also emitted when fire retardant is burned. Emission factors determined from the burn experiments are extrapolated to estimate the quantity of VOC and ammonia emissions from the Bitterroot-Lolo National Forest fire in 2016 to understand how fire retardant contributes to air pollution emissions.