NIOSH Advises College to Review Ventilation in Response to IEQ Complaints

Published June 10, 2015

During a recent health hazard evaluation (HHE), NIOSH staff evaluated indoor environmental quality (IEQ) conditions in a college campus building that housed offices, classrooms, and a dental clinic. The HHE was requested by an employer representative who notified the agency that employees were concerned about perceived poor IEQ in the building.

NIOSH personnel found no evidence of past or current water damage, water entering the building, or mold during their walk-through survey of the building. Though the ventilation system appeared well maintained and functioned as designed, the NIOSH report indicates two conditions that could lead to airborne contaminants from the dental clinic spreading to other parts of the building. According to the report, return air from the dental clinic was mixing with return air from offices and classrooms before being recirculated, and the dental clinic was not kept under a consistent neutral or negative air pressure relative to surrounding areas of the building. NIOSH staff also found one uncapped plumbing vent in a cabinet in the dental laboratory.

NIOSH personnel conducted interviews with building occupants as part of their evaluation, and most interviewed occupants reported “nonspecific symptoms common to workplaces and in the general population.” NIOSH staff did not identify current problems with the building that could be associated with employees’ symptoms. However, the report states that one employee may have developed hypersensitivity pneumonitis from working in the building when mold problems were found in 2001.

The NIOSH report recommends that the college consult with a ventilation engineer to review the ventilation system design for the building for possible improvements. The college should also stop environmental sampling for chemical and biological agents, which had been ongoing over the past 13 years. NIOSH also recommends that employees using portable ionizing air cleaners should stop use because the devices may release ozone, which can cause symptoms similar to those reported during the interviews.

View the full NIOSH report as a PDF. Other HHE reports are available on the agency’s website.