Atmospheric air quality monitoring is a systematic observation of the state of the atmosphere, the content of harmful substances in it. This work is very important in connection with the growth of pollution. To ensure the monitoring of the atmospheric air of the city, a modern organizational and technological base is used. Observation can be carried out at stationary posts or in mobile laboratories.
Main pollutants
Human activities contribute to an increase in the concentration of dust, soot, liquid aerosols and chemical molecules in the air.
- Dust pollution is associated with both natural causes and agricultural work, construction, industry, traffic, etc. Any dust (not just industrial) is harmful to the human respiratory system. Asbestos dust is considered the most harmful. Some speciesdust may contain radioactive substances and other harmful components. Dust pollution affects the radiation balance and the nature of precipitation. It slightly slows down human-caused global warming. To combat atmospheric dust, protective forest belts, tree plantings, and filters are being created. Sometimes they use watering the territory, filling the soil, on which plants are then planted. For those who must constantly or frequently inhale dust, personal protective equipment is recommended.
- Soot emissions are associated with the operation of vehicles, thermal power plants, industrial enterprises, landfills. It is released when plastics, coal, oil and oil products, biomass, and sometimes natural gas are burned. Soot can absorb harmful substances and in this case it is harmful to human he alth. Soot itself is a product of burning organic matter, which is not toxic. It reduces the flow of solar radiation, and when it hits snow or ice, it accelerates its melting, contributing to global warming.
- Chemical aerosols are formed when sulfur or nitrogen compounds react with water vapor to form droplets of acids. Falling to the surface, they can cause acid rain. Aerosols also cause an increase in cloudiness and an increase in the reflectivity of the Earth. Aerosols significantly slow down global warming. Sulfur and nitrogen compounds are emitted during the operation of vehicles, thermal power plants, and industrial enterprises. And also during volcanic eruptions.
- Gas (molecular) substances are very diverse and are released under various natural andanthropogenic processes. Of greatest importance are emissions of harmful substances and greenhouse gases. Greenhouse and ozone-depleting gases often remain in the atmosphere for centuries and have widespread effects on radiative fluxes. Methane is the highest penetrating agent in the atmosphere, having the lightest molecule, making it a versatile greenhouse gas.
Why environmental monitoring is done
Concentration of pollutants in the atmospheric air is not constant and depends on many factors. Therefore, systematic monitoring of its composition is required. They allow to calculate the average level of pollution, the dependence of the level of pollution on the direction of the wind, to determine the dynamics of pollution and its composition. Monitoring is most important near highways, industrial enterprises, in the central parts of the city, as well as in places remote from human activity.
The results of environmental monitoring of atmospheric air are important for decision-making, both at the local and state levels. High transport pollution indicates the need to unload highways, the construction of bypass roads around the city. If severe pollution is found near industrial facilities, then this means that measures are needed to improve the operation of treatment facilities or it is necessary to expand the sanitary protection zone. Rising levels of pollutants at remote stations are indicative of unfavorable regional or global trends whenthe solution to the problem is possible only at the state or international level.
Monitoring methods
Monitoring of air pollution can be carried out in different ways. Usually 3 options are used:
- Stationary, when all observations are made from one observation station.
- Route, when several sampling points are used for observation.
- Mobile, when measurements are taken from different points, depending on the direction of the winds.
Stationary monitoring
Stationary monitoring is used for long-term and high-quality observation, similar to observation at a weather station. Such laboratories are placed in the most convenient places. The data obtained make it possible to assess the dynamics of pollution levels over a long period of time. And both as a whole and for individual components. Sampling is done regularly.
Route type of monitoring
Route observations allow you to cover several points at once, when setting posts in each of them is inappropriate. In this case, a fairly detailed study of the composition of air in a certain area is obtained. Vehicles are used to carry out such observations. Sampling is carried out at the same points in the area. A laboratory on wheels can handle up to 10 observation points per day, but on average, 3 to 5 points are used for observations. Measurements are taken at the same time, and the order of visiting places does not change.
Mobilemonitoring
Mobile observation posts, often referred to as flare stations, are used to take samples directly outside the plant. Vehicles are also used for such observations. At the same time, a certain distance from the chimneys to the measurement sites is observed. The number of measurement points is large, their location and measurement time is determined by the situation or spontaneously. Sampling occurs within a short period of time.
The general rules for any measurement points are open terrain and solid ground or pavement underfoot.
Features of stationary observations
Before the installation of stationary pavilions, the following activities are carried out:
- Preliminary concentrations of pollutants are determined, for which calculations and data from other observation posts are used.
- The features of the relief and the nature of development are being studied.
- Plans are being explored for future development in the area, especially for industrial plants.
- Comprehensive studies of the meteorological situation in the area are being carried out.
- The intended role of transport and energy is being determined.
The number of stationary posts in a settlement is determined by its size, the number of inhabitants, the environmental situation, the amount of greenery. If the ecological situation is not favorable, then posts can be placed at the rate of: 1 post per 5–10 km. Observation posts are located in different environmental conditions: neartrails, in green spaces, in residential and industrial areas.
In our country, for the standardization of observations, the same type of pavilions of the POST type are used, which have the same equipment. Such standardization allows minimizing the spread of possible errors that could arise due to differences in the technical features of the devices. All stationary observations are carried out every day, regardless of the seasons and weather conditions.
Features of mobile laboratories
As a mobile laboratory in our country, the standard model "Atmosfera-P" is used. In addition to equipment for measuring air quality, it is equipped with devices for meteorological measurements. It is used for route and mobile observations. There are some restrictions on operating conditions:
- The temperature inside the vehicle should not exceed 35°C.
- Atmospheric pressure should be between 680-790 mm Hg. st.
- The upper humidity limit is 80 percent.
- Even on hard pavement, speed must not exceed 50 km/h.
To determine the direction and speed of the wind, a sensor is used, which is located on the roof of the car.
What air quality monitoring does
Atmospheric air monitoring systems are important due to the impact of harmful substances on human he alth and the environment. ATIn some countries, such as India, air pollution is one of the main causes of disease and premature death. Measuring the composition of atmospheric air makes it possible to assess the concentration of pollutants and identify cases where their level exceeds the MPC. If this is the case, it may make sense to develop a set of measures to reduce the level to a safe level. Main objectives of ambient air pollution monitoring:
- Collection of information on the quantity and dynamics of pollutants in the observation area.
- Develop adequate measures to reduce pollution.
- Reducing the harm from the work of industrial enterprises for people living in the observation area.
- Assessment of the level of transport pollution on city streets.
- Evaluation of the feasibility of placing new industrial enterprises or transport interchanges in the study area.
- Creating a database on the ecological situation in the study area.
State air monitoring
All information obtained by monitoring the quality of atmospheric air is then analyzed by environmentalists. Over time, measurement techniques become simpler and more accessible. In Russia, state monitoring of atmospheric air pollution is carried out everywhere. It is one of the components of state environmental monitoring. It is carried out by federal and other executive authorities in accordance with the procedure adopted by the Government of the Russian Federation. List of facilities where atmospheric air monitoring is mandatory,established by territorial authorities.
Conclusion
Thus, monitoring the state of atmospheric air is a very important work in the modern world. The he alth and well-being of many people depends on its quality. Atmospheric air monitoring methods are different and depend on the tasks and terrain conditions. Naturally, tracking alone is not enough to solve environmental problems. It only provides the authorities and the public with the necessary information. On its basis, it is necessary to take adequate measures to reduce the level of air pollution.
