Evaluation of indoor environmental quality in a college teaching and administrative building ; NIOSH health hazard evaluation report

The Health Hazard Evaluation Program received a request from a college to evaluate employees' concerns about health symptoms that were believed to be related to the indoor environmental quality in a campus building. The building had a history of indoor environmental quality complaints, but was mostly unoccupied at the time of our visit in May 2013. During our visit, we looked for past or current water damage, water entering the building, and mold. We interviewed current and former college faculty, managers, and staff. We reviewed (1) ventilation system drawings and maintenance records, (2) reports from indoor environmental quality consultants, and (3) the college's summary of symptoms reported by employees and students. We found the ventilation systems to be well maintained, but airborne contaminants in the dental clinic could spread to other areas of the building. First, the return air from the dental clinic mixed with return air from offices and classrooms before recirculation. Second, the dental clinic was not under a consistent neutral or negative air pressure relative to surrounding areas, meaning that air from the dental clinic could flow to adjacent areas. We saw no evidence of current or past water damage, water entering the building, or mold. Most interviewed employees reported nonspecific symptoms common to workplaces and in the general population. We could not link these symptoms to any specific workplace exposure. One employee may have had a lung condition that could be caused by mold exposure. This employee worked in the building in 2001 when mold problems were found. Additional findings included: (1) some employees using portable ionizing air cleaners (a source of ozone and possibly associated with employee symptoms), and (2) a sewer pipe vented into a cabinet in the dental laboratory. We recommended the employer work with a ventilation engineer to change how return air is mixed and to improve airflow, check for open sewer vents inside the building, and stop sampling for chemical and biological ...