by Sylvain Comeau

Next time construction workers start tearing down walls in that empty office across the hall, you might want to open a window, or even take a week off. Renovation work may well be the culprit in many cases of sick building syndrome.

Lan Chi Nguyen Thi just completed her Master’s thesis in Building Engineering, in which she conducted a study on contaminants released by renovations. She found that high levels of chemical emissions and organic contaminants like mold spores, were released by metal welding, the removal of old carpets and ceiling tiles, and other commonplace renovation activities.

However, Nguyen Thi says, building owners fail to take the air quality problems stemming from renovations seriously enough.

“The impact on indoor air quality is not well controlled. Problems come up because people are not moved out of buildings during renovations; they may be moved to another office on the same floor, or at best, to another floor. That’s not enough to prevent a drop in air quality,” she said in an interview.

For most, the issue is comfort level, although some people are more sensitive to emissions.

“Even after a renovation, the level of exposure in a typical office building won’t make you drop to the floor and choke, but it can be uncomfortable and unpleasant over the long term if you work there every day, with symptoms like headaches and respiratory irritation. And there is also a segment of the population who get very sick, because they suffer from allergies and chemical sensitivities,” Nguyen Thi said.

Renovations are a major contributor to indoor air quality problems, “because we have so many old buildings now,” said Gemma Kerr, who is co-thesis supervisor along with Building Engineering Professor Fariborz Haghighat. “We are not actually putting up that many new buildings. Mostly we just renovate old buildings, so that a new type of activity can take place there, or a new tenant can move in.

“There is almost continuous renovation work going on, so there are lots of opportunities for problems to arise.”

Renovations can essentially tear away the barriers that had previously sealed in assorted contaminants, unleashing them into the air. Kerr provides some unpleasant examples.

“Fumes from glue may get into the ventilation system when workers are painting or caulking or mold spores can get out into other parts of the building and start new mold colonies when water-damaged drywalls are torn down.”

Nguyen Thi and Kerr say they will pursue this research, assuming a sponsor emerges, as partners in their Ottawa-based consulting company, InAIR Environmental Ltd. They hope that this kind of research will eventually lead to new government regulations protecting office workers; current regulations only protect the construction workers doing the renovation, and no regulations at all cover the problem of mold.

That’s because we don’t really know how mold affects people, Kerr said. “We do know that a healthy person may be able to withstand certain levels of exposure to mold, while someone who is more vulnerable may get very ill.”

Mold has been much in the news lately, following the death of a patient at the Royal Victoria Hospital after exposure to mold spores in an operating room.

In a related study, Nguyen Thi and Kerr suggest some protocols for landlords who want to keep their tenants happy and healthy. Ultimately, they would like to produce a simple document with clear guidelines that building owners can follow, to fill the void until new government regulations are put in place.

“Once you know what kinds of contaminants are generated by each activity, then you can come up with guidelines on what kinds of barriers should be used,” Nguyen Thi said. “My goal is not to produce numbers and figures, because building owners don’t care about that. They just want to know: How do I make sure that occupants in the building are not affected by the renovation? How do I keep problems from spreading?”

“We examine the effectiveness of procedures to protect office workers,” Kerr added. “It can be very simple, depending on the extent of the renovation being done, and other factors. It may require fans blowing air out the window, or plastic sheeting, or simply closing the door. Small steps like that could make a big difference.”

The study was sponsored by the American Society for Heating, Refrigerating and Air Conditioning Engineers.