Monitoring and analysis of secondary water supply quality of passenger train in a certain district / 公共卫生与预防医学

ABSTRACT

Objectives To investigate the sanitary condition of the secondary water supply for passenger trains in the administration area, to evaluate the influencing factors of the secondary water supply system for passenger trains, and to put forward suggestions for improving the water quality of the secondary water supply for passenger trains. Methods The water quality of secondary water supply of 48 trains of 24 pairs of CRH type passenger trains and 160 trains of 10 pairs of type 22 passenger trains and 30 pairs of type 25 passenger trains in Lanzhou Railway Bureau in 2019 was analyzed and compared. Results The qualification rate of 208 samples tested was 73.08%. The qualification rate of secondary water supply quality of type 22 and 25 passenger trains was 62.50% and 66.67%, respectively, and the difference was not statistically significant（χ2=0.23 ，P＞0.05）. The qualification rate of secondary water supply of CRH passenger train was 97.92%, which was statistically significantly different compared with that of type 22 and 25 passenger trains（χ2=18.40, 18.15, P2=0.056, 0.054, 0.056, 0.22, 0, and 0.22, P>0.05). The total number of bacterial colonies, total coliform, turbidity and iron in the secondary water supply of type 22 and 25 passenger trains did not meet the standard, while only one water sample for the secondary water supply of CRH passenger trains did not meet the standard. Conclusion The quality of secondary water supply of CRH passenger train is obviously better than that of type 22 and 25 passenger trains. Changing the position of defecation port and water injection pipe of type 22 and 25 passenger trains, selecting non direct train defecation collection system, or adding appropriate amount of chlorine disinfectant into the water supply hose can significantly improve the qualification rate of bacteriological indexes of secondary water supply of passenger trains.