Volatile Organic Compounds Measured at a Telephone Switching Center From 5/30/85-12/6/88: A Detailed Case Study

Abstract

Volatile organic compounds (VOCs) can cause failures in electronic equipment. This paper presents detailed observations from a three year study of VOCs at a telephone switching office in Neenah, Wisconsin. Included are data on matched indoor and outdoor VOC measurements, as well as corresponding data on HVAC fan operation and ventilation rates. The Neenah office has few occupants and hence provides an opportunity to examine factors that influence VOC levels without the complications associated with daily human activities.

As reported in other studies, total VOC levels indoors were greater than those outdoors. During normal periods (no renovation or construction) the total VOC levels were inversely proportional to the air exchange rates. The sources with the greatest influence on the VOC levels tended to be those with the greatest surface area. The results demonstrate that low baseline levels of VOCs (total VOCs < 60 μg/m³) can be achieved by minimizing VOC sources and providing adequate ventilation. Even during construction and installation of new switching equipment, the VOC levels, although elevated, remained within tolerable limits (total VOCs < 500 μg/m³). Three months after this activity, levels had returned to pre-installation values. Low concentrations of VOCs and low concentrations of airborne particles were not mutually exclusive, nor was it unduly expensive to achieve such low levels.