Air pollution is considered to be one of the most burning problems of environment preserving. If without water and food people can live during a few weeks, without air they can die in several seconds. The question under consideration here is to choose any air pollutant and find out the most reasonable and appropriate way of its sample collection and analysis.
Ecology experts and scientists outline six main criteria of air pollutants. The group consists of ground-level ozone, particulate pollution, carbon monoxide, lead, nitrogen oxides and sulfur oxides. These criteria are believed to have the strongest impact on the environment and provoke the most serious health problems in humans.
Carbon monoxide is a chemical compound that is the result of fossil fuels burning. Except the motor vehicles fires and some other industrial equipment are the sources of carbon monoxide. This gas is dangerous for human health as it influences hemoglobin and blocks transportation of oxygen to body cells. In this case the insufficient amount of oxygen in blood reduces the traditional work of body’s organs; it can cause diseases and may lead to death.
There are several ways of measuring criteria of air pollutants. The most reasonable method of sample collection for carbon monoxide is validated method presented by OSHA, when air volume from 2 to 5 liters is collected and put into special sampling bag with five layers of aluminization. In order to collect the necessary amount of air, a low-flow rate sampling pump is usually used. In the laboratory the ionization detector is applied for air sample analyzing. For this reason collected air from the aluminized sampling bag is put into a gas chromatograph.
Carbon monoxide is detached from carbon dioxide, hydrocarbons (except methane), as well as water with a stripper column through application of semi-continuous method that is fully automated. . After that, carbon monoxide and methane are taken apart on an analytical column, and the carbon monoxide is sent further through a catalytic reduction tube. Later carbon monoxide is changed to methane. The carbon monoxide, which already is in the form of methane, is going to the next stage through a flame ionization detector. The signal that establishes the final result is in direct proportion to the concentration of carbon monoxide in the air (Carbon monoxide).
The advantage of this method is that analysis in the laboratory should be made no more than within fourteen days after air was put into sampling bag. This means that it is impossible to delay investigation and it helps to deliver results on time. Moreover, this method is preferable to use because its precision and accuracy value is very high, while bias and overall error values are low. Moreover, the level of air humidity has no impact on the analysis result; and this very sample may be also investigated for the content of other air pollutants criteria.
Speaking about the type sample collection, grab or continuous sample it is quite difficult to choose the one or another. Both of them are good. The only difference between them is the area of their application. For instance, grab sample is better to use for measuring fuel engines gas emissions. The obtained result will not be changed with time flow, as it is directly connected with technical characteristics of vehicle and fuel it consumes. Continuous sample collection is advised to be applied for measuring industrial carbon monoxide emissions, as CO content in this case depends on branch of industry, applied technologies and the amount of produced goods. Continuous sample collection will help to monitor the changes in CO emissions and reveal total damage, which a particular enterprise can cause.
To sum it up, it is important to emphasize that air pollution is a continuous and dangerous process. People should understand that we should pay attention at this problem in order to find out air pollutant criteria and take measures to reduce their bad impact on the environment. That is why method of carbon monoxide collection and analysis described above is the most reasonable and appropriate to use as it provides good accuracy values and are available to be applied by any laboratory.