Studies on sources of airborne microorganisms and on indoor air quality in a large office building.
Morey-PR; Jones-WG; Clere-JL; Sorenson-WG
Proceedings of the ASHRAE Conference IAQ'86, Managing Indoor Air for Health and Energy Conservation, April 20-23, 1986; Atlanta, Georgia, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. 1986; :500-509
A 1983 study of indoor air quality and sources of microbial contamination in a large office building was presented, as well as results of a 1985 follow up study on the same building. As a result of employees complaining of building related illnesses, NIOSH was invited to conduct the 1983 survey. Airborne microorganisms were collected with instruments using the principle of impaction onto a semisolid culture medium, and a comfort ballot was used to obtain information on how the occupants of the building perceived indoor environmental conditions. The heating, ventilation and air conditioning system (HVAC) was also evaluated. Indoor microbial contamination was found to be associated with recurrent floods, improper preventive maintenance of the air handling unit (AHU) and fan coil unit (FCU) filters, and stagnant water in the AHU and FCU drain pans. Air flow measurements showed that inadequate amounts of outside air were being supplied to the occupants of the building. Widespread complaints by occupants of headaches, upper respiratory irritation and stuffy air were all indicative of sick building syndrome. A number of recommendations were made to reduce microbial contamination and increase the supply of outside air. The follow up study in 1985 showed that monthly replacement of AHU and FCU filters had eliminated this source of microbial contamination. However, other sources of contamination such as the porous insulation within AHUs were found. Measurements of carbon-dioxide levels showed that the supply of outdoor air was still inadequate, and occupants continued to have symptoms of sick building syndrome. The authors conclude that further significant changes in the HVAC system of the building are necessary.
Ventilation-equipment; Air-conditioning-equipment; Equipment-design; Air-flow; Air-filters; Bacteria; Fungi; Air-contamination; Office-workers; Air-quality-monitoring; Workplace-studies
Proceedings of the ASHRAE Conference IAQ'86, Managing Indoor Air for Health and Energy Conservation, April 20-23, 1986; Atlanta, Georgia, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.