旅客空调列车车厢空气质量与空调通风系统卫生学调查

Investigation of Air Quality in Passenger Train and Hygienic Status of Air-Conditioning System

目的了解旅客列车车厢空气质量和空调系统的卫生状况。方法于2009年1—10月,抽取合肥车辆段空调列车车厢108节,其中,硬座车厢30节、硬卧车厢28节、餐车车厢24节(燃煤燃电各12节)、软卧车厢26节。测定车厢空气的PM10、细菌总数、风速、温度、相对湿度、CO2,空调回风管道中的积尘量、细菌总数、真菌总数、β-溶血性链球菌及送风口PM10、细菌总数、真菌总数、β-溶血性链球菌。结果车厢空气CO2的合格率最低(59.2%),其次为温度(67.6%)、相对湿度(79.6%)、风速(91.3%)、PM10(98.1%),细菌总数均合格。CO2合格率为硬座[36.7%(11/30)]<硬卧[50.0%(14/28)]<餐车[70.8%(17/24)]<软卧[84.6%(22/26)]。不同运行年限车厢空气温度、相对湿度、风速、CO2、PM10、空气细菌合格率间比较,差异均无统计学意义。列车空调通风系统回风管细菌总数的合格率最低(15.6%),其次为回风管积尘量(51.5%)、送风口细菌总数(59.2%)、送风口PM10(82.4%)、送风口真菌总数(96.3%)、回风管真菌总数(98.9%)、送风口和回风管β-溶血性链球菌(100.0%)。车厢PM10与送风口PM10(rs=0.824,P<0.001)以及车厢细菌与送风口细菌(rs=0.521,P<0.001)均呈正相关。结论本次调查的旅客列车车厢主要卫生学问题是空气CO2污染和空调回风管细菌总数超标。

Objective To investigate the air quality in the passenger train with air-conditioning ventilation system. Methods Based on the stratified cluster random sampling, from January to October in 2009, a total of 108 train carriages with air-conditioning system were selected to conduct the hygienic survey in Hefei, including 30 third class carriages, 28 third class sleeping carriages,24 dining carriages （coal was used in 12, electricity was used in 12） and 26 carriages with soft berths. PM10,bacteria count, air velocity, temperature,relative humidity, carbon dioxide inside the carriges were determined. The dirt retention quantity,bacteria count,fungus count, β-hemolytic streptococcus in the return air pipe were measured. The PM10, bacteria count,fungus count,β-hemolytic streptococcus at the point of air outlet were also determined. Results The qualified rate of carbon dioxide in carriages was only 59.3% ,which was the lowest. The qualified rates of temperature, relative humidity, air velocity and PM10 were 67.6%, 79.6%, 91.3% and 98.1%, respectively. As for the bacteria count, all were qualified. The qualified rate of carbon dioxide in third class carriages was 36.7%（11/30）,it was 50.0%（14/28） in third class sleeping carriages, in dining it was 70.8%（17/24） and in carriages with soft berths it was 84.6%（24/26）, respectively. The qualified rate of bacteria count in the return air pipe was 15.6%, which was the lowest. The qualified rate of dust deposition at the point of air outlet was 51.5%, bacteria count in the return air pipe was 59.2%, PM10 in the return air pipe was 82.4%, fungus count in the return air pipe was 96.3%, fungus count at the point of air outlet was 98.9%, β-hemolytic streptococcus in the return air pipe and at the point of air outlet was 100.0%, respectively. There was positive relationship between the PM10 concentration inside the compartment and the PM 10 concentration at the air outlet （rs=0.824,P〈0.001）. There was also positive relationship between the bacteria count inside the compartment and the bacteria count at the air outlet （r8=0.521 ,P〈0.001）. Conclusion The main hygienic problems are carbon dioxide pollution in the carriages and bacteria contamination in the return air pipe of air conditioning.