In buildings and boardrooms . . .

The walls are coming to life

by Tamara Fernandes

reathe a sigh of relief if your workplace suffers from sick-building syndrome -- help is on its way.

Horticultural science professor Mike Dixon and a team of researchers that includes research associate Allan Darlington and Prof. Bernie Grodzinski, Horticultural Science, and Prof. Chris Hall, Environmental Biology, are creating a "breathing wall." This ecological engineering development is the product of Genetron Systems Ltd.

The research team, sponsored by the Canada Life Assurance Company and the Institute for Space and Terrestrial Science (ISTS), has been evaluating the wall's potential for dealing with poor indoor air quality.

The wall is an ecologically complex and stable biological community capable of improving air quality in partially closed building environments. It is made up of 400 plant species and 50 to 60 animal species (mainly fish, amphibians and some insects). The fish are housed in an aquarium structure at the base of the wall.

"Clean-air generation is what happens routinely outside your window," says Dixon. "What we've done is find a way to package what nature does outdoors and put it in an indoor system."

Air quality is one of office workers' biggest beefs. The presence of a number of contaminants is believed to cause sick-building syndrome. That's when a significant percentage of a building's users complain of acute discomfort, including fatigue, congestion, eye irritations and headaches, while indoors.

The breathing wall may help office workers overcome this effect by both the sheer process of photosynthesis -- using up carbon dioxide and releasing oxygen into the atmosphere -- and natural air filtration. Air is filtered when it passes through the porous lava rocks that make up the wall's base structure. The plant material on the wall, along with the associated microbial population, is believed to take up other common contaminants or metabolize them into a less toxic state.

Contaminants include volatile organic compounds such as toluene, formaldehyde and trichloroethylene. These compounds originate on surfaces and objects found commonly in office buildings, such as carpeting, photocopy machines, building materials, paint and hair spray.

In controlled tests, the breathing wall was capable of removing between 50 and 80 per cent of some contaminants introduced to the system. But the researchers found there were far too many variables influencing and interacting in the system to quantify the volume of wall required to generate a given amount of clean air.

A prototype of this structure was tested successfully in the boardroom of the Canada Life Assurance Company in Toronto. The researchers found that in addition to improving air quality, the wall is esthetically pleasing. This has potential for producing a positive psychological effect on the occupants of the building; studies to evaluate this are planned.

In addition to the support it receives from ISTS and Canada Life, this project is sponsored by the Ontario Ministry of Environment and Energy and the Ontario Ministry of Agriculture, Food and Rural Affairs.