Six Steps for Improving Indoor Air Quality

Article excerpt

Today environmental concerns are shared by everyone, particularly among property managers. Our medical vocabulary now features such ominous terms as "sick building syndrome" and "Legionnaire's Disease.' It is a consumer issue which captures media headlines. It is a financial issue, as well, for those who worry about the prospect of litigation and loathe to spend tens of thousands of dollars on yet another "possible" health risk.

What is a sick building?

A sick building is one in which at least 20 percent of the occupants exhibit several of the following symptoms: headache, dizziness, drowsiness, fatigue, nausea, and irritation of the eyes and respiratory system. If these manifestations persist for more than two weeks and disappear or abate when the tenants leave the building, the symptoms are probably caused by a build-up of contaminants within the building.

Honeywell's Indoor Air Quality Diagnostic Center estimates that 20 percent of the buildings in the United States have air-quality problems.

Years of energy-conscious building management has made building envelopes tighter and ventilation schedules more stringent. In a sense we have created a new problem in solving an older one. As we enter an era of renewed energy awareness, it is necessary to reorder our priorities and strive for bottom-line economies that maximize both energy conservation and clean indoor air.

Exposing tenants to contaminated air can be a costly affair. Even if only a few individuals become ill, the cost of litigation can be enormous. A recent article in the Wall Street Journal stated that "Sick-building suits could rival those that have proliferated over asbestos." And unless the offending conditions are diagnosed and corrected immediately, they can be expected to worsen, portending still more lawsuits, unfavorable publicity, tenant cancellations, and government intervention.

Yet, in many cases, indoor air quality can be achieved with a six-step, practical approach to cleaning up the air and maintaining a healthy indoor environment. This simple system is aimed at preventing problems in buildings before they occur and at assuring building owners and property management that they are providing a healthy and productive environment for their tenants, without significant financial outlays.

Become familiar with indoor

air quality standards

The most powerful of the air quality standards is ASHRAE 62-1989, enacted recently by the American Society of Heating, Refrigeration and Air Conditioning Engineers. This respected organization has considerable power in the construction industry and its new air quality standard affects the design of every new building. While not directly enforceable in existing buildings, it can serve as a valuable guideline for assuring acceptable air quality and defining the limits of liability.

Because most buildings were designed before ASHRAE 62-1989 was written, they are probably not in compliance. The requirement is a minimum airflow of 15 cubic feet per minute (cfm) per person, and in most situations the standard is 20 cfm or more. Specific requirements depend on occupant density and the activity for which the space is used.

Further, the standard specifies that these quantities be verified by measurement in the occupant's breathing zone, not by inspection of the operations manual or measurements in the duct-work. This recognizes the fact that duct leakage, obstructions in work space, and poor air distribution may reduce air flow, even though adequate ventilation is available.

Many buildings may be able to comply with these new provisions without retrofit expense merely by altering damper positions. If a system is undersized, modifications will be necessary.

Another provision of ASHRAE 62-1989 requires that outside air used for ventilation meets federal ambient air quality standards. This suggests that the outside air supply may have to be curtailed during critical periods of pollution, e. …