Researchers collaborate to improve our air

by Janice Hamilton

Photo: Concordia engineering professor Fariborz Haghighat (left) and McGill professor of medicine Jean-Pierre Farant are doing research and supervising graduate students together.

What do paint, cleaning materials, carpets, chairs, even new clothes and toys made from synthetics have in common? They can all be sources of odours that contribute to poor indoor air quality. Some can even make us sick. But few of us think twice when we bring them into our homes or workplaces.

Concerned about the problems posed by these contaminants, two professors at Concordia and McGill are sharing their expertise and lab facilities to identify and monitor sources of indoor air pollution.

Fariborz Haghighat, Graduate Program Director of Concordia's Department of Building, Civil and Environmental Engineering, is collaborating with Jean-Pierre Farant, a professor of occupational health in the Faculty of Medicine at McGill, and director of the Environmental Research Labs there.

"Our two labs complement each other," Haghighat said. Farant added that because labs of this type are costly, both universities benefit. In his lab, Haghighat puts samples of materials such as carpet or linoleum into containers, then takes air samples to see whether they emit gases. He sends the air samples over to McGill to be identified.

Indoor air quality has become an increasingly serious problem in recent years because buildings are more tightly sealed, and because people, especially children and the elderly, spend more time indoors than ever before. Farant and Haghighat suspect the increased incidence of asthma in children is related to airborne contaminants in homes and daycares, and they are planning a study to identify the chemical culprits and their sources.

Haghighat, a ventilation expert, and Farland met in 1992 and began collaborating soon after. One joint project involved monitoring air quality in 20 Montreal office buildings. Currently, they are jointly supervising several graduate students, including McGill PhD student Soheil Rastan, who is developing an instrument that can identify the main source of air contamination in a building.

"When a new building opens, people often complain about the smell," Haghighat explained. The conventional approach to finding the source of an odour is to take samples of the various materials present and test them in the lab. Rastan is developing a cup-like instrument that can sample the air next to each piece of furniture, carpet, and other potential sources in the room. The air contains a combination of all contaminants, so on-site sampling should give a more accurate picture of what goes on.

Another McGill PhD student, Alan Rossner, is perfecting a simple-to-use sensor that people can employ themselves to monitor and identify the sources of contaminants in their homes or workplaces. An earlier model of this sensor was used on the space shuttle. Both Rossner and Rastan use the Concordia lab to double-check the findings of their sensors.

Concordia Master's student Julia Popa, who is also being co-supervised, is studying the way new building materials can act as sponges, absorbing contaminants from the air and later releasing them, just as rooms can retain the smell of cigarette smoke. "She is looking at how a material absorbs a chemical and releases it later on," Haghighat explained.

Haghighat has also been collaborating with the Danish Institute of Building Research in a study of the perception of odours. "We measure the chemical coming from the material, and simultaneously ask people how they perceive the odour so we can correlate the two," he said.

Noting a parallel to wine tasters and perfume testers, he continued, "We are trying to find out how chemicals in the air affect odour perception. The ultimate aim is to develop a sensor that could act like a human nose." When installed, such a sensor could control the amount of fresh air coming into a building so that air quality improves while energy consumption remains minimal.

For more on asthma information available at Concordia, click here.