Monitoring air quality is a systematic observation of the state of the atmosphere, the content of harmful substances in it. This work is very important due to increased pollution. To ensure the monitoring of atmospheric air of the city, a modern organizational and technological base is used. Surveillance can be carried out at stationary posts or in mobile laboratories.
Major pollutants
Human activity contributes 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, the movement of cars, etc. Any dust (not just industrial) is harmful to the human respiratory system. Asbestos dust is considered the most harmful. Some types of dust may contain radioactive substances and other harmful components. Dust pollution affects the radiation balance and precipitation pattern. It slightly inhibits human-induced global warming. Protective forest belts, tree planting, filters are created to combat atmospheric dust. Sometimes watering the territory, filling the soil, on which plants are then planted, are used. For those who are forced to constantly or often 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 during the burning of plastics, coal, oil and petroleum products, biomass, and sometimes natural gas. Soot can absorb harmful substances and in this case it is harmful to human health. Soot itself is a product of burning organics that 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 by the reaction of sulfur or nitrogen compounds with water vapor to form acid droplets. 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 markedly inhibit global warming. Sulfur and nitrogen compounds are released during the operation of vehicles, thermal power plants, and industrial enterprises. And also with volcanic eruptions.
- Gas (molecular) substances are very diverse and are released during various natural and anthropogenic processes. Emissions of unhealthy substances and greenhouse gases are of the greatest importance. Greenhouse and ozone-depleting gases often remain in the atmosphere for centuries and have a ubiquitous effect on radiation flows. Methane, which has the lightest molecule, penetrates the atmosphere most of all, making it a universal greenhouse gas.
Why environmental monitoring
The concentration of pollutants in the air is variable and depends on many reasons. Therefore, systematic monitoring of its composition is required. They allow you 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. The most important monitoring is 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 for unloading highways, the construction of bypass routes around the city. If severe pollution is found near industrial facilities, this means that measures are needed to improve the operation of treatment facilities or it is necessary to expand the sanitary protection zone. An increase in the content of pollutants at remote stations indicates unfavorable regional or global trends when a solution to the problem is possible only at the state or international level.
Monitoring methods
Air pollution can be monitored in different ways. Usually use 3 options:
- Stationary, when all observations are made from one observation station.
- Route, when several points for sampling are used for observation.
- Mobile, when measurements are made 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 allow us to assess the dynamics of the pollution level over a long time. Moreover, as a whole, and for individual components. Sampling is done regularly.
Route view of monitoring
Route observations allow you to cover several points at once, when the installation of posts in each of them is impractical. In this case, a rather detailed study of the air composition in a certain territory is obtained. To carry out such observations, vehicles are used. Sampling is carried out at the same points in the terrain. A laboratory on wheels can master up to 10 observation points per day, however, on average, from 3 to 5 points are used for observations. Measurements are taken at the same time, and the order of visiting places does not change.
Mobile monitoring
Mobile observation posts, often referred to as trickle lights, are used to take samples directly near the facility. For such observations, vehicles are also used. In this case, a certain distance from the chimneys to the places of measurements is observed. The number of measurement points is large, their location and measurement time is determined by the situation or spontaneously. Sampling takes place over a short period of time.
General rules for any measurement point are open terrain and the presence of dense soil or cover underfoot.
Features of stationary observations
Before installing stationary pavilions, the following activities are carried out:
- Preliminary concentrations of pollutants are determined, for which they use calculations and data from other observation posts.
- The features of the relief and the nature of the buildings are being studied.
- Plans for future development of the area are being studied, especially with regard to industrial enterprises.
- Comprehensive studies of the meteorological situation in the area are being carried out.
- The estimated role of transport and energy is determined.
The number of stationary posts in a village is determined by its size, number of inhabitants, environmental conditions, and the amount of greenery. If the environmental situation is not favorable, then the posts can be placed at the rate of: 1 post per 5-10 km. Observation posts are located in different environmental conditions: near highways, in green spaces, in residential and industrial areas.
In our country, for the standardization of observations using the same type of POST type pavilions, which have the same equipment. Such standardization allows you to minimize 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
In our country, the standard Atmosphere-P model is used as a mobile laboratory. 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 limitations in operating conditions:
- The temperature inside the car should not be higher than 35 ° C.
- Permissible values of atmospheric pressure should be in the range of 680–790 mm Hg. Art.
- The upper limit of permissible humidity is 80 percent.
- Even on hard artificial turf, the speed should not exceed 50 km / h.
To determine the direction and speed of the wind, a sensor is used that is located on the roof of the car.
What gives air quality monitoring
Air monitoring systems are important in connection with the effect of harmful substances on human health and the environment. In some countries, such as India, air pollution is one of the main causes of disease and premature death. Measuring the composition of atmospheric air allows us to estimate the concentration of pollutants and to identify cases when their level exceeds the MPC. If there is one, it may make sense to develop a set of measures to reduce the level to safe. The main objectives of monitoring air pollution:
- Collection of information on the number and dynamics of pollutants in the observation zone.
- Development of adequate measures to reduce pollution.
- Reducing the harm from the work of industrial enterprises for people living in the observation zone.
- Assessment of the level of transport pollution on the streets.
- Assessment of the feasibility of placing new industrial enterprises or transport interchanges in the study area.
- Creation of a database on the environmental situation in the study area.
State monitoring of atmospheric air
All information obtained by monitoring the quality of atmospheric air is then analyzed by environmentalists. Over time, measurement techniques become simpler and more affordable. In Russia, state monitoring of 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 bodies in accordance with the procedure adopted by the Government of the Russian Federation. The list of facilities where atmospheric air monitoring is mandatory is established by the territorial authorities.
Conclusion
Thus, monitoring the state of atmospheric air is a very important work in the modern world. The health and well-being of many people depends on its quality. The methods for monitoring atmospheric air are different and depend on the tasks and conditions of the area. 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.