
One difficulty in effectively studying indoor air quality is that several diverse areas of expertise are needed, including chemistry, microbiology and ventilation engineering. Healthy Buildings International integrated these skills in forming unique diagnostic teams to study internal air quality.
In reviewing these building studies worldwide, Healthy Buildings International scientists have found that sixty-three percent of the problems with contaminated air are due to ignorance of correct operating practices and/or inadequate maintenance, rather than any fundamental building design problems.
While it is true that pollutants in buildings emanate from the outdoors and indoors – carpets, furniture, people, equipment, ventilation systems and staff activities such as cleaning, smoking and food preparation – correctly designed and operated ventilation systems are built to handle these challenges. Unfortunately, because some building operators or maintenance employees are apathetic or ignorant of the ventilation system, the problem of poor indoor air quality standards persists.
In 1987, the United States National Institute for Occupational Safety and Health (NIOSH) studied 466 buildings following staff complaints of upper respiratory illness and poor air quality. The study concluded that more than half of the problems were due to inadequate ventilation.
At Healthy Buildings International, the findings have been similar. After inspecting more than 1,136 major buildings totaling more than 15.7 million square meters of property, the three most common causes of “sick buildings” were:
1. Poor Ventilation: fifty percent of the buildings had inadequate fresh air and an alarming eighteen percent were operating with no fresh air whatsoever.
2. Inadequate Filtration: fifty-six percent of the buildings had inefficient filters, forty one percent were basically low grade filter pads, scarcely better than butterfly nets, and fifteen percent were of reasonable quality but poorly installed.
3. Lack of Hygiene: forty-two percent of the ventilation systems were dirty including nine percent with grossly contaminated duct work. Such contaminated systems make perfect breeding grounds for bacteria, moulds and fungi.
In fact, only thirty-eight percent of the buildings studied were well ventilated with efficiently filtered air handling units and clean, well maintained ventilation systems. Significantly, there were no complaints of poor air quality by employees in these buildings.