Indoor environment and air quality in hospital units : Symptoms and signs

Abstract: Indoor environment may influence the occurrence of symptoms such as eye, skin and upper airway irritation, headache and fatigue. The aim of the dissertation was to study relations between subjective indoor air quality, such symptoms, clinical signs from the nose and the eyes and the physical indoor environment, in particular the effect of dampness, type of building, and air humidification. The studies were performed in geriatric hospital units in southern Sweden. The technical investigations comprised a building survey and measurements of indoor air factors, including building dampness in the floor construction. Subjective indoor air quality, and symptoms were related to both personal factors, building characteristics, and the indoor environment. Perception of stuffy air and odour was more common in poorly ventilated buildings. Eye irritation and dry facial skin were more common in new buildings. Air humidification reduced the perception of dry air, static electricity and throat symptoms.Headache, fatigue, reduced tear film break up time (BUT), increased lysozyme concentration in nasal lavage and symptoms from the eye, nose and throat were more common in damp buildings with emission of 2-etyl-1-hexanol, and related to measured dampness and ammonia in the floor.Complaints on air dryness and stuffy air were more common in damp buildings. The hospital workers in a new building with special design, built by an anthroposophic society, had less complaints on perceived air and symptoms, and increased BUT. It is concluded that symptoms and complaints on air quality are common among hospital workers, and related to measurable environmental factors, psychosocial climate and personal factors. Our results indicate that measurement of biomarkers in nasal lavage, and measurement of tear film stability, could be useful tools to study human reactions to the indoor environment. From a preventive point of view, to create healthy buildings, the physical and psychosocial climate must be satisfactory, building dampness should be avoided, room temperature should be 20-22 °C. Subjective air quality and the occurrence of symptoms may also be influenced by selection of building materials, building design and air humidification.