Hygienic Investigation of Air Conditioning System of Public Places / 环境与健康杂志

ABSTRACT

Objective To understand the sanitary status of the air conditioning system of public places and to discuss the countermeasure.Methods Fifty public places where the air conditioning system were used were selected as the research objects in September 2008.The questionnaires about the hygienic management, the air conditioning system and the cooling tower were used to investigate the basic situations of the air conditioning system in public places,and Legionella pneumophila(Lp) of cooling water in the cooling tower was detected.Results All the fifty public places didn't establish complete sanitary management system.90% of the cooling towers were less than one kilometer from the residential areas, schools, kindergartens, agedness flats and hospitals.And 18% of the cooling towers were less than one hundred meters from the walking streets and entertainment plaza.Moreover,8% of the public places had not fresh air, the air purification wasn't installed in 74% of the public places and sterilization equipments, and automatic or on-line sterilization equipments in the cooling towers weren't installed in all the public places.In addition, the positive rate of Legionella pneumophila in the cooling towers was 89.58%.Thereinto, the positive rate of Lp1 type(79.07%) of Legionella pneumophila was significantly higher than that of Lp2-Lp14 type(11.63%) as well as that of Lp1 type and Lp2-Lp14 type(9.30%)(P0.05).Conclusion The air conditioning systems of public places are being faced with some sanitary problems and the cooling water in the cooling tower was polluted with Legionella pneumophila.Therefore,it is suggested that its sanitary management should be reinforced and the sterilization management of cooling water as well as the shield between the cooling towers and the circumferences should be taken into account.