By Damond Benningfield in 40 Acres, Jan | Feb 2020 on |

On a sunny autumn afternoon, wires are taped to the walls and ceiling of UTest House, a nondescript three-bedroom, two-bath structure on the corner of an otherwise vacant lot at the Pickle campus in north Austin. The wires converge in a cramped control room, which soon will be phased out in favor of a facility in an adjacent shed. Tanks of carbon dioxide, which is released to trace air movements in the house, perch in a corner of the control room. Microphone stands, which hold monitoring instruments, form an obstacle course through the 1,300-square-foot house, and carpet squares stand near the front door, creating an environment that looks both structured and chaotic.

“Everything is improvised,” says Atila Novoselac, an engineering professor and supervisor of UTest House. “We’re doing everything here for the first time.”

UTest House was designed to allow researchers to study the effects of paints, cleaners, and other substances on the quality of indoor air. Researchers also study how building materials and stuff inside the walls and ceiling pollute the outdoor air that enters the house. By letting dust accumulate on vinyl flooring, for example, researchers discovered that small children and pregnant women could be exposed to dangerous levels of chemicals that can affect growth and development.

“In a week or two, you can get high levels of these chemicals leaching from the floor into the dust,” says Richard Corsi, a professor emeritus of engineering and supervisor on the project. “If a child crawls across the floor, it kicks up the dust and inhales a lot of it. That shows that you should be damp-mopping the floor regularly.”

Corsi, who moved to Oregon in 2018 to become dean of the College of Engineering and Computer Science at Portland State University but maintains his UT affiliation, adds that the average American lives to be 79 years old and spends 70 of those years indoor. “And 54 of those years are spent in their own home, which is just extraordinary,” Corsi says. “So, the dominant exposure to bad stuff in the air is likely to be in our homes, not outdoors.”

Novoselac agrees, adding that there are many unknowns in an indoor environment, and that the exposure to chemicals is an order of higher magnitude there.

“So when you study indoor air quality, it’s like opening Pandora’s box,” he says. “While you’re trying to answer one question, three more open up. For us, that’s a gold mine. We don’t need to look for problems—they’re all around.”

UTest House began as part of a new interdisciplinary program, funded by the National Science Foundation, to train PhD students in indoor environmental science. The NSF grant allowed the program to request money for instrumentation, and Corsi inquired whether a house would qualify. “They said ‘You could try,’” he recalls. The agency bought Corsi’s justification, and the house was set up in 2006. Today, it’s supported by government and private foundation grants and contracts from businesses. “We’re basically running a small company,” Novoselac says.

The UTest House is the endgame. The researchers begin their studies by conducting small-scale testing in chambers the size of large microwave ovens, evaluating small samples of paint or other household compounds. They then move up to room-sized chambers where the environment is tightly controlled.

After that, the experiment moves to UTest House, which provides conditions like those found in a typical home. “Testing in the house is completely different than the lab,” Novoselac says. “In the lab you don’t have the natural environment—the wind, solar radiation, temperature fluctuations. So, we have to step away from the lab and test in more real-world conditions.”

A few years ago, those conditions told the UTest House team that clay-based plasters and paints remove ozone from outdoor air that seeps in through cracks in the walls, but they don’t add any contaminants of their own. And in 2018, 60 researchers from 12 universities selected UTest House as the site for HOMEChem, a month-long extravaganza in which the scientists analyzed the effects of cooking and cleaning on the air and on the contamination on cabinets, floors, and other surfaces. They’re still analyzing the results.

Novoselac is also studying a question he’s been pondering for a while: What happens when you let your air-conditioner fan blow constantly instead of cycling when the thermostat cuts on and off? So far, he hypothesizes, as air bypasses the cooling coil, removing humidity, the moisture condenses inside ducts. Dust, almost an organic soil, accumulates on that moisture.

“That’s ground for growing the wrong kind of mold,” he says. “I can’t prove that that’s very bad, but I’m searching for funding to study it”—in a house where dust is always welcome.

Engineering professor Atila Novoselac inside the UTest House, by Brian Goldman