When people spend more time inside workplaces and homes, their awareness of indoor environmental quality increases. Sometimes, poor indoor air quality (IAQ) is obvious and inhabitants can quickly identify its source. More frequently, however, accurate determination of the nature and extent of IAQ problems requires scientific measurements. Many circumstances can cause indoor air degradation. Among these are inadequate fresh air being drawn into a building, excess moisture in a building’s air supply as well as prior use of harmful building materials. The first signs of poor indoor air quality may be obvious, such as noxious odors. Other, subtler signs may include excess dust on indoor surfaces or building inhabitants becoming unusually sleepy in the afternoons.
