Study on The Composition and Risks of Fire Effluent Condensate

Pioneering Pilot Study Explores the Composition and Risks of Fire Effluent Condensate

December 13, 2023

When you were a kid, did you ever breathe on a cold window and see the moisture in your breath turn into tiny water droplets on the glass? In a similar way, as the high-temperature smoke from a fire meets cooler surfaces, water and other vapors in the smoke can turn into small droplets. In addition to water, this liquid condensate may include other compounds that present human health concerns, including known and probable carcinogens. 

UL’s Fire Research Safety Institute (FSRI) and UL Solutions recently published a pilot study on the composition and associated risks of condensate from residential fires in the journal Fire Technology. This study builds on our work exploring post-fire water contamination in the wildland urban interface (WUI). It is the first of its kind, and its results point to how condensate may create health concerns for direct human exposure and for water distribution systems. 

To explore the composition and risks of fire effluent condensate, FSRI conducted a series of five full-scale room-and-contents fire experiments. They started by collecting baseline measures of condensate in the home. Next, they ignited a fire within the home and eventually extinguished the fire, continually measuring gas temperatures; collecting samples of the condensate produced; and analyzing the amount of volatile organic compounds, anions, and pH in the condensate. They then repeated the experiment four more times, varying the fuel load and external ventilation across the experiments. They also collected and analyzed runoff water samples to compare concentrations of these same compounds that may contaminate water used during firefighting activities. 

Images from  Pilot Study on Fire Effluent Condensate from Full Scale Residential Fires
Pre-test pictures of the fuel load for each experiment on fire effluent condensate

Results Demonstrated Carcinogens in Fire Effluent Condensate

The results of these experiments revealed elevated concentrations of several anions as well as various volatile organic compounds, including benzene, toluene, xylenes, styrene, naphthalene, and acetone. Notably, concentrations of benzene and naphthalene exceeded typical water quality standards. Peak benzene levels were similar to those observed in contaminated water distribution systems following wildfires. In addition, four out of five samples contained chloride concentrations well above the Environmental Protection Agency criteria. These findings provide important evidence for smoke effluent being drawn into compromised piping and condensing, which may subsequently impact drinking water quality.

This pioneering study has shed light on the composition and potential risks associated with fire effluent condensate, revealing relatively high concentrations of known and probable carcinogens. The findings not only deepen our understanding of the effluent released in a fire but also establish the groundwork for continued research and proactive measures to safeguard public health and the environment in the face of these WUI fire events.  

“Our research provides important information on the risks posed by fire effluent condensate and opens doors to new avenues of scientific inquiry. While further research is needed, it’s a valuable step forward in our mission to advance fire safety knowledge to address fire risks and emerging dangers,” said Dr. Gavin Horn, principal researcher on the study.

Read the peer-reviewed journal article: Pilot Study on Fire Effluent Condensate from Full Scale Residential Fires

About Fire Technology:

Fire Technology is a scientific journal that publishes original contributions, both theoretical and empirical, that contribute to the solution of problems in fire safety science and engineering. It is the leading journal in the field, publishing applied research dealing with the full range of actual and potential fire hazards facing humans and the environment. It covers the entire domain of fire safety science and engineering problems relevant in industrial, operational, cultural, and environmental applications, including modeling, testing, detection, suppression, human behavior, wildfires, structures, and risk analysis.

Examining Post-Fire Water Contamination in the Wildland Urban Interface