The next time you hear someone say about an office building: “This place is really sick!” don’t assume iths just an angry employee. It could be an environmental engineer or a medical expert talking about what the U.S. Environmental Protection Agency (EPA) lists among the five most important environmental issues in the United States–sick building syndrome (SBS).
Beginning in the late 1970s, many people working in recently built or remodeled buildings began to complain about respiratory problems, fatigue, and flu-like symptoms, for no apparent reason. The people noticed, however, that the symptoms would disappear when they went home at night and over a weekend. This led doctors and other experts treating these people to look at the buildings as the source of the illness.
Within a few years, the range of building-related symptoms grew to include headache, nose and throat problems, fatigue, eye irritation, and a variety of other troubling, though not acute, physical complaints. Today, the EPA estimates that as many as 30 percent of new or remodeled buildings may cause such problems in some of their occupants.
Making a Diagnosis
When SBS symptoms begin to occur within a building, a team of environmental and medical investigators often makes an inspection of the building and conducts a survey of the people working there. Currently, experts estimate that when 20 percent to 30 percent of the questionnaires from people in a single building show such symptoms, the building is “sick.”
SBS is sometimes confused with building-related illness (BRI), which typically involves an acute infection such as Legionnaires’ disease (actually a potent type of pneumonia) or certain kinds of asthma or allergies. Often, BRI starts in and is spread by the ventilation system. That was the case in the famous outbreak of Legionnaire’s disease in 1976 in Philadelphia. A recent outbreak in a federal office building in Richmond, California, alsow as linked to the ventilation system.
But just because building-related illnesses are more dangerous doesn’t lessen the importance of SBS. Many more people and buildings are affected by SBS than BRI. And when you can no longer go to work without getting sick, or when you start taking more sick days and being less productive, SBS has become a major health problem.
But what could cause SBS? And why did it only start to appear in the late 1970s? Scientists have been unable to find a direct cause-and-effect relationshop between the characteristics of the indoor environment in sick buildings and the SBS symptoms. The scientists’ frustration with the difficulty of finding a cause of SBS is clear when they say “there’s no smoking gun” or “we’re trying to hit a moving target.”
New Kid on the Block
Why is SBS a relative newcomer on the environmental scene? Experts point to the fact that in the last 15 to 20 years building design has stressed centralized heating and air-conditioning systems and more tightly sealed buildings.
In the 1970s, the price of energy skyrocketed. So architects, engineers, and building operators all looked for ways to make buildings more energy-efficient. Because heating and cooling were the two major energy consumers in a building, they immediately looked at ways of wringing more efficiency out of the ventilation system. That meant reusing the heated (or cooled) air within a building as much as possible. To do that, they brought in less fresh air from outside.
Recommended rates of ventilation with outdoor air were dropped from the 15 cubic feet per minute (CFM) recommended by building codes in the 1930s to just 5 CFM in the 1970s. This dramatically reduced air circulatiwn whrn combined with buildings that were now essentially sealed boxes, allowing indoor air pollutants to build up to levels that some scientists believe can trigger SBS symptoms. Of some 350 SBS investigations made by the National Institute for Occupational Safety and Health (NIOSH), ventilation problems were found in nearly 50 percent of the cases. As a result of these findings, building codes have now increased recommended ventilation rates to 20 CFM.
Seeking the Source
But the existence of ventilation problems does not necessarily prove that poor ventilation causes SBS. Many buildings with poor ventilation, for example, do not have SBS. In fact, the latest research indicates that in spite of its prevalence in newer buildings, ventilation problems may not be the SBS “smoking gun” that scientists are looking for. Put another way, simply increasing the ventilation rate may not cure a sick building; there are many other factors to be considered.
Besides poor ventilation rates, experts have identified the following characteristics that could cause SBS symptoms:
* Equipment and materials. Copiers can give off ozone. Synthetic materials used in carpets and adhesives can release toxic fumes.
* Dust and other things that can be breathed in, known as respirable particulate matter (RPM), can be put into the air froM furniture and building materials.
* Poor location fo air ducts inside the building creates bad air-circulation patterns. This results in “dead spots” where little air moves and pollutants from the sources listed above can accumulate.
* Ventilation intake and exhaust locations. Poor placement can such outside pollutants, including the building’s own exhaust, back inside the building.
These are just a few of the many suspects that scientists and engineers are studying to try to identify the causes of SBS. Currently, they admit they’re stumped. But increase research and ongoing attempts to cure known sick buildings may help take some of our buildings off the critical list.
Related article: Treating a Sick Building
How do you treat a “patient” who is 10 stories high, full of steel, concret, and glass, and who makes other people sick? That’s the challenge facing the “building doctors” in Bartow, Florida, trying to “cure” the Polk County Courthouse.
In the fice years since the new courthouse opened, about one-third of the 600 courthhouse employees have complained of sick building syndrome (SBS) symptoms: headaches, fatigue, nausea, and more. That percentage is large enough to consider the building “sick.” But is does little to help investigators “diazgnose” the cause of the building’s sickness. Even among doctors treating the courthouse workers, there’s little agreement about which worker illnesses are related to the building and which are from other sources.
Assuming that worker symptoms can be linked to the building, it still leaves investigators puzzled over what in the building environment is causing the SBS symptoms. The heating and air-conditioning systems? Carpets or furnishings? The building structure itself? The way the building is operated? Scientists have yer to find specific causes for SBS in the Polk County Courthouse or in other SBS sites around the country.
Treating a sick building is not cheap, either. In an attempt to eliminate SBS in the Polk County Courthouse, its bricks, air-conditioning system, roof, and windows are being completely replaced at a cost of nearly $20 million. Will the patient recover? The prognosis is still up in the air.