空调公共汽车内空气中菌落总数及二氧化碳浓度分析

目的了解不同乘客人数、不同季节、不同天气条件的空调公共汽车内空气污染状况,为制定相应的防制对策提供依据。方法选择不同乘客人数、不同季节、不同天气条件的空调公共汽车,分别测定车厢空气中菌落总数及CO2的浓度。结果在微小气候基本相同及开启空调通风系统的条件下,空调公共汽车内空气中菌落总数及CO2浓度在不同乘客人数段差异有统计学意义(P<0.05),随着乘客人数的增加,菌落总数及CO2平均浓度也显著增高。CO2平均浓度严重超标,部分车辆的空气菌落总数亦超标。CO2的最高浓度超出我国《室内空气质量标准》GB/T18883-2002最高容许浓度的7.3倍。在车内乘客人数接近的条件下,空调公共汽车在冬、春季的菌落总数及CO2平均浓度均显著高于夏、秋季。从晴天、阴天到雨天,菌落总数及CO2平均浓度均逐渐降低,车内空气质量逐渐改善。结论空调公共汽车内空气中菌落总数及CO2浓度水平与乘客人数、天气和季节具有一定关系。空调公共汽车这个密闭的公共场所应给予高度警惕和加强防范。

Analysis of Carbon Dioxide Concentration and Aerobic Bacterial Count in Air- conditioned Bus

Objective To investigate the state of air contamination in air-conditioned bus and to provide evidences for instituting relevant countermeasures.Methods The concentration of carbon dioxide and aerobic bacterial count were measured in air-conditioned bus with different quantity of passengers in different seasons and different weather condition.Results Under the same microclimate with the opening of air-condition and ventilation facilities,the difference of carbon dioxide concentration and aerobic bacterial count in air-conditioned bus with different quantity of passengers showed statistical significant differences,and as the increase of passengers the concentration of carbon dioxide and aerobic bacterial count increased significantly.The concentration of carbon dioxide was severely out of the required standard,which was 7.3 times more than that of the maximum allowable concentration in the indoor air quality standard GB/T18883-2002,and aerobic bacterial count in partial buses was also out of the required standard.In the condition of same quantity of passengers,the carbon dioxide concentration and aerobic bacterial count in air-conditioned bus in spring and winter were higher than in summer and autumn.The two indexes in bus stepped down from sunny,cloudy to rainy days and the air quality in bus improved gradually.Conclusion The carbon dioxide concentration and aerobic bacterial count in air-conditioned bus are related to the number of passengers,season and weather variation.It is necessary for us to strengthen precaution to air-conditioned bus because it is a air-tight public place.