In the quest to understand and improve indoor air quality, a team of researchers led by Andrew B. Martin from the University of Colorado Boulder has shed new light on how particulate matter (PM2.5) from cooking emissions travels through multi-story houses. Their findings, published in the journal *Indoor Environments* (translated from the original title), could have significant implications for the energy sector and indoor air quality management.
Martin and his team instrumented a multi-story test house with 13 PM2.5 monitors to track the movement of fine particulate matter generated from cooking activities. They found that about 10% of ambient PM2.5 concentrations penetrated indoors with a time lag of approximately one hour when there was no indoor activity. Interestingly, both pan frying and air frying of the same food ingredients produced similar peak PM2.5 concentrations.
The study revealed that it took between 2 to 4 minutes for kitchen peak concentrations to reach other sensors on the first floor and about 8 minutes to reach the second floor. “This time lag is crucial for understanding how pollutants spread throughout a house,” Martin explained. “It highlights the importance of ventilation strategies to mitigate exposure.”
The researchers also discovered that PM2.5 concentrations were heterogeneous on the first floor, with non-kitchen areas peaking at 45% ± 9% of kitchen levels. On the second floor, concentrations were more homogeneous, peaking at 18% ± 2% of kitchen levels. Using a typical occupancy scenario, the highest estimated personal PM2.5 exposure (44%) was experienced in the kitchen/dining area, which accounted for 9% of the time spent at home.
To analyze particle transport throughout the house, the team employed three modeling approaches with increasing input requirements: a multi-box model, an empirical model, and the NIST CONTAM model. All models successfully predicted time-integrated PM2.5 concentrations on both floors, with R2 values ranging from 0.57 to 0.82 and RMSE from 6 µg m−3 to 11 µg m−3.
“This research provides a comprehensive understanding of how cooking emissions travel through a house,” Martin said. “It’s a stepping stone towards developing more effective ventilation and air filtration strategies.”
The findings could have significant commercial impacts for the energy sector. As buildings become more energy-efficient, the need for effective indoor air quality management becomes increasingly important. Understanding the transport of particulate matter can help in designing better ventilation systems that balance energy efficiency with air quality.
Moreover, the study highlights the potential for low-cost sensors to monitor indoor air quality, making it more accessible for homeowners and businesses to take proactive measures. “Low-cost sensors are a game-changer,” Martin noted. “They make it possible to collect detailed data on indoor air quality without breaking the bank.”
As the world continues to grapple with the challenges of indoor air pollution, this research offers valuable insights that could shape future developments in the field. By understanding how pollutants move through our homes, we can take steps to create healthier indoor environments.