Ventilation rate as a determinant of symptoms and perceived odors among workers in daycare centers: Fid-Bau Portal

Ventilation rate as a determinant of symptoms and perceived odors among workers in daycare centers

Ruotsalainen, Risto / Jaakkola, Niina / Jaakkola, Jouni J.K.

Abstract The objective of this study was to assess symptoms related to the sick building syndrome (SBS) and perceived odors among daycare workers, relative to ventilation rates in Finnish daycare centers. A random sample of 30 daycare centers in the city of Espoo was selected for the study. The study population consisted of 268 female nursing workers, who filled in a questionnaire inquiring about symptoms, perceived air quality, and their possible personal and environmental determinants. The response rate was 96%. The ventilation system in most of the daycare centers (63%) was mechanical supply and exhaust; the rest of the centers (37%) had mechanical exhaust only. The exhaust airflows in the children's rooms varied remakably, ranging from 0 to 11 L/s per person (average 4.0 L/s per person). The air change rate varied from 0 to 5 m³/hm³ (average 1.61/h). Though potential personal and environmental confounders were controlled, no consistent associations were observed between the magnitude of airflows or air change rate and the occurence of symptoms or unpleasant odors experienced by the workers. The results indicate that relatively low mehanical ventilation rates are not associated with SBS symptoms and unpleasant odors in conditions where the potential sources of odor are strong and air change is not totally dependent on mechanical ventilation (windows are openable).