중앙집중식 냉방시설의 냉각탑수중 레지오넬라균과 실내외 미생물 분포에 관한 연구

Abstract

Cooling towers water has frequently been known as a source of infection in outbreaks of Legionnaires' disease and a source of indoor air pollution. However, there have been a few reports on the presence of Legionella in cooling towers water and aerosols of various public facilities. This study was carried out to investigate the indoor and outdoor distribution of Legionella spp and microbe from 132 cooling towers water of public facilities detected L. pneumophila in Seoul and Gyeonggi-Do areas. The results showed that the L.pneumophila among the selected 132 cooling towers was detected mostly in July (12.0%), followed by August (4.0%) and June, September no-detected. The L. pneumophila in public facilities was detected mostly in department store (27.3%), followed by hospital (8.7%), office building (5.9%), big market (5.0%) and hotel, subway no-detected. The pH values of cooling towers water with presence of L. pneumophila showed mostly 8.0 or higher (9.5%), followed by 7.0~8.0 (6.8%), lower 7.0 no-detected. The temperature of cooling towers water with presence of L. pnemophila showed mostly 30oC or higher (9.8%), followed by 26~30oC (6.9%), lower 25oC no-detected. The turbidity of cooling towers water with presence of L. pneumophila showed mostly 1~2 NTU (8.8%), followed by above 2NTU (5.9%), lower 1NTU no-detected. The correlation coefficient between indoor and outdoor concentration of microbes in public facilities showed 0.67 in Legionella spp. (p>0.05), 0.93 in bacteria (p<0.01), 0.94 in fungus (p<0.01), 0.98 in coilform (p<0.01), respectively.