Energy Week Winner: Measuring Air Quality on UT Shuttles

Measuring air quality on buses

After measuring air quality during 50 shuttle trips between the Pickle Research Center and main campus, Sahil Bhandari, a graduate student in Center for Energy and Environmental Resources at the Cockrell School of Engineering, presented his findings to the Longhorn Energy Club poster competition held during the 2018 Energy Week—and  won.  Bhandari’s research received the Environment and Sustainability award for efficiently and inexpensively collecting data to gain insight into students’ exposure to pollutants.

The UT Shuttles operated by Austin’s CapMetro offer a sustainable way to commute to and from campus. This system—the largest university shuttle system in the US—provides millions of free rides to UT students, faculty and staff each year. The current research project, funded by a Green Fee grant, intends to both give feedback to CapMetro on current air quality and help build a complete picture of air quality among UT students as part of the research led by Lea Hildebrandt Ruiz, assistant professor in the McKetta Department of Chemical Engineering.

“This project directly addresses health concerns in student lives from public transit use, including exposure to particulate and gaseous pollutants from shuttle idling and infiltration from the outside environment while riding,” says Bhandari. “This project serves as a leap forward towards social equity and ties into the broader sustainability initiatives of the City of Austin, namely, the Austin Mobility Project and the CapMetro Connections 2025 Transit plan.”

The research by Bhandari took place over two months during the 2017-18 winter.  During each trip, he added a personal exposure monitoring system, or air quality instruments, and a GPS to a backpack. The combined instrumentation measured and mapped pollution and particulate levels in the air, including gas phase CO, CO2, and suspended particulate matter (from 0.3 to 10 microns in size). Additional measurements of exposure were conducted in cars, in UT office and lab spaces and in homes for comparison.

Bhandari found that while time spent on a bus accounted for a quarter of the time for which particulate matter was sampled, it accounted for almost half of the total exposure to particulate matter. It should also be noted that the highest levels of pollutants were found indoors while cooking and in a car while on the highway.

“Human’s exposure to air pollution, or how much pollution a person inhales, is determined by pollutant concentrations and people’s activity pattern,” says Hildebrandt Ruiz. “A main focus of our research group is to understand how pollutants form and transform in the atmosphere, which determines their concentrations. Sahil’s project measures concentrations of pollutants during a person’s normal work day, enabling exposure assessment. A better understanding of pollutant exposure will allow for more targeted policies to reduce concentrations and exposure, thereby improving human health.”