Research on Portland's Harriet Tubman Middle School wins student paper competition

Brett Stinson, a research assistant at the Healthy Building Research Laboratory at Portland State, is making the most of his senior year at the University. Under the guidance of mechanical engineering professor Elliott Gall, Stinson recently won the student thesis paper competition sponsored by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Stinson is also a member of the research team from Professor Gall's lab that recently won the Environmental Protection Agency's Cleaner Indoor Air During Wildfires Challenge for the design and testing of "The Cocoon," a do-it-yourself air filter that removes wildfire-smoke-associated pollutants from indoor environments.

Stinson's thesis, "Determining Airflows and Volatile Organic Compound Source Strengths for an Occupied School," analyzed datasets collected during Professor Gall's 2019 study of indoor air quality at Portland's Harriet Tubman Middle School. The purpose of the initial research, conducted before Stinson arrived at Portland State, was to evaluate the effectiveness of improvements to the school's design and HVAC systems meant to reduce levels of harmful pollutants within the school from nearby Interstate 5. Stinson's research expanded on that work by developing methods to analyze the sources of volatile organic compounds (VOCs) during periods when the building was empty and occupied by students.

Consumer products, building materials, human metabolism, and vehicles are all familiar sources of VOCs, which have negative health impacts, particularly for vulnerable populations. 

By measuring the emission rates of VOCs from these sources, Stinson's work provides insights into an area of indoor air quality research few in the field have examined. It also provides strong evidence that after the improvements to the building, a major source of VOCs within Harriet Tubman Middle School are the students, faculty, staff, and the products they use.

"This work again shows that the building design and particle-phase and gas-phase air cleaning systems in the building are doing a good job removing pollution from the freeway," Stinson said. "It also shows us that when the students and staff arrive, the VOCs go up, and when they leave, the VOCs go down. And that tells us, people are an important source of VOCs in indoor spaces."

Stinson's analysis examined 249 compounds. However, his thesis focuses on eleven VOCs--seven commonly associated with human metabolism or activity and four associated with traffic. The results demonstrate much higher levels of VOCs from sources within the school than from the freeway. Worth noting, though, is that the toxicity of the VOCs measured varies considerably; some VOCs are relatively benign while others are acutely harmful.

Stinson, the president of PSU's chapter of ASHRAE, presented his paper at the competition in January. Winning the competition provided him the opportunity to travel (on a full travel scholarship) to ASHRAE's national conference in Las Vegas, where he presented again. In May, he travels to The Netherlands to compete at the 2022 REHVA World Student Competition.

Stinson graduates with a Bachelor's in mechanical engineering at the end of the Spring Term. He is enrolled in the department's Bachelor's + Master's Pathway program and will be entering graduate school at PSU in the fall, studying in Professor Gall's lab. For his graduate studies, Stinson plans to continue his research on indoor air quality during wildfire smoke events and is considering entering a Ph.D. program after completing his graduate studies.