Effect of Reducing Fine Particle Concentration after Use of Air Purifiers in Hospital: Preliminary Results

Abstract

Most hospitals have air-conditioning facilities, but many people are moving, and there are many indoor air pollutants such as fine particle. In this study, air purifier is installed in hospital ward to investigate the improvement of indoor air pollution. We installed 25 air purifiers in 4th floor ward of a university hospital in Seoul, Republic of Korea. The air purifier filter is turned on and off at intervals of 4 weeks, and the indoor fine particle concentration is continuously measured through the dust sensors of the air purifiers. We obtained the outdoor fine particle data from the nearest Air Korea measuring station. We compared indoor fine particle concentrations before and after using the air purifier and compared those after stratification of the types of place (single rooms, rooms with five or six beds, nurse stations, and patient rest room). We also analyzed the average difference and correlation between indoor and outdoor fine particle concentrations. After the use of air purifiers, the difference of indoor and outdoor fine particles concentrations are larger and the correlation between outdoor and indoor fine particle was also lower than that before the use of air purifiers. The average difference of indoor fine particle before and after use of air purifier was about 3.46-5.68 μg/m3. Among the four types of places, the nurse stations had the highest concentration of fine particles, the lowest patient rest room, and there was a difference between the groups.Despite having air conditioning facilities in the hospital, indoor fine particle concentration was lower when air purifiers was used than before use of air purifiers. Particularly in places where people are moving a lot in the ward, fine dust is high. Therefore, additional efforts are needed to lower the concentration of fine particle in hospitals such as use of air purifiers.