The development of odor emission rates from EU6 classified glass fiber bag filters was studied in four air-handling units (A HU), and emissions from the same kind of filters with EU3 classified polyester prefilters were studied in two units. The filters were loaded in six AHU in downtown Helsinki. The pressure drop was measured, and the odors of the filters were evaluated by a trained panel under laboratory conditions (T= 20o C, face velocity 1. 0 m/s) every sixth week. The odor emissions of simultaneous atmospheric dust samples were also studied.

In two case-referent studies the associations between questionnaire symptom reports, expressed as SES (Sick Building Syndrome) in office workers or facial skin symptoms among VDT-workers, and physical data from offices in 160 buildings were investigated. The results show that low outdoor airflow rate and presence of certain pollution sources, such as copying machines, tended to be associated with an elevated prevalence of SES.