Study On Ambient Air Quality In Subway Cars

With the emergence of traffic congestion, public transport has become more and more people's travel choices, according to the survey, there are about more than 60% of Beijing citizens rely on public transport, and rail traffic is favored for its own advantages. As more and more people choose the subway as their travel public transport, the time people take the subway is also grow, air quality in subway cars compartments adverse effects on the human body attracts wide attention from scholars at home and abroad. At present, State Environmental Protection Administration has launched the in-vehicle air pollutant concentration limits and measurement methods for development, but due to in-car air pollution has many technical problems, thus, today there is not a similar standard. Therefore, considerable scientific evaluation of subway environment air quality to safeguard health and improve the management level of Metro operation company is of great theoretical significance.In this study, we select 5 lines of the train carriage and transfer station of Beijing rail transit system which is representative, monitoring of the air condition of the car, the platform and the outdoor. Through reference both at home and abroad literature and related information, select the four kinds of the most representative polluting gas in the carriage: carbon dioxide?CO₂?, volatile organic compounds?VOC?, particulate matter can be entered into the lung?PM2.5? and carbon monoxide?CO?, through air monitoring instrument on its car, platform and platform outside atmosphere in the concentration for measurement analysis, in order to clarify the time and space variation law of air pollutants in subway cars and its influencing factors, to provide scientific basis for the formulation of relevant standards and norms.This research has selected 5 representative lines in the subway of Beijing, carbon dioxide, volatile organic compounds, carbon dioxide and carbon monoxide were monitored in carriage, platform, atmosphere at different times and in different congestion levels. Based on the monitoring data, using statistical analysis to be effects of crowding on the concentration of pollutants in the compartment, and the carriages and the platform outside the station and air pollutant concentrations were analyzed, and correlation analysis of air pollutants on the compartment.Study finds widespread air pollutants in Beijing subway cars higher pollutant concentrations in the carriage during the morning and evening peak, at noon time low concentrations of this characteristic. During morning and evening peak periods of excessive pollutant concentration is more serious through the analysis of contaminants in subway cars, found the subway underground pollutants concentration in overcrowding there is a positive correlation between four measures and there is a positive relationship between air pollutants. In the study, the congestion degree of the compartment is divided into 5 types: free state, seat state, no seat but no seat, no congestion, congestion and severe congestion, the classification standard of air quality in subway carriage based on the inside of the compartment is established, which has no influence on the human body, has slight influence on the human body and has a great influence on the human body.Proposed Metro managers comprehensive examination taking into account air quality in sensitive people and crowding effects on air quality inside train compartments, make effective management methods and measures to improve subway cars in the air quality, safeguarding the health of users.