Air quality monitoring system

As a fast means of transportation, while the subway brings convenience to people's travel.   There are also some problems, including air quality problems. Due to the relatively closed space in the subway station, the air and the atmosphere are isolated, and it is basically in a static and non-circulating state. The air quality is relatively poor, which poses a certain hidden danger to the health of passengers.

Factors affecting air quality in subway stations:

1. Air conditioning system. Air conditioner filter adsorption can remove some pollutants, and outdoor air exchange can dilute the concentration of pollutants and effectively reduce biological pollution.

2. Indoor return air. In order to save energy, the system uses indoor return air to reduce the fresh air volume, and the polluted air returns to the room again, causing secondary pollution.

3. Polluted air outside the station. The polluted air outside the station is directly sent indoors as fresh air

4. Piston wind. The underground tunnels are dark and humid, and the air quality is poor. Through the piston effect, the humid air in the tunnel enters the station.

Major air pollutants in subway stations:

1. Carbon dioxide, this problem seems to be inevitable during rush hour. Since everyone outputs CO2 to the space they are in, when the CO2 concentration exceeds 1000 ppm, people will start to experience drowsiness, difficulty breathing, and drowsiness.

2. There are two main sources of inhalable particles, PM10 and PM2.5.  One of the reasons is that a large number of particles generated by the friction between the subway wheels and the rails when the train passes are affected by the piston wind when entering the subway. The other is the dust carried by the human body, and the secondary dust is formed by crowding and friction.

3. Ammonia, when there are many people in the subway, you will smell the stench from time to time. This is the smell of ammonia. Ammonia is a gas with a pungent odor. After ammonia enters the lungs, it has a stimulating effect on the mucous membranes.

4. Bacteria are easy to breed under certain conditions, such as suitable humidity, excessive dust, insufficient light, etc. After the human body inhales particulate matter that carries bacteria, it can cause various infectious diseases

Indoor Air Quality Systems and improvement in subway stations:

Faced with the complex air environment of subway stations or other underground spaces, it is impossible to fully understand the long-term environmental quality by relying on one-time testing in the early stage.  Using the intelligent online environmental Air Quality Monitor, it is possible to monitor and understand the changes in the subway environment for a long time. On the one hand.  We can monitor the contents of PM2.5, CO2, ammonia and other indicators in the environment in real time, and timely find the areas where the air pollution index exceeds the standard.

Air quality systems using IoT technology. It can monitor indoor temperature, humidity, light, particulate matter (PM2.5/PM10), carbon dioxide, VOC, formaldehyde and other environmental factors, and collect the required data. And transmit the data to the monitoring terminal and display terminal in real time. It enables managers and tourists to see environmental data through monitoring terminals and multimedia displays. And the system provides efficient technical means for the effective management, monitoring, evaluation and regulation of indoor environmental quality such as traffic places, and can detect and suppress various environmental pollution factors in time. Keep traffic participants in a "stable, clean, and safe" environment.