EPA \ TAQMN \ Air Quality Monitoring \ Photochemical Site \ Goal

Monitor Goal

The following points are used to explain the purpose and goals of monitoring O3 precursors.

Specific information is closely related to emission types

Each emission type, such as traffic, industrial or vegetation emission has its own unique composition. Therefore monitoring different VOCS is helpful in determining the contribution of different sources to O3 formation and provides essential reference information for O3 control.

Provides Direct Photochemical Evidence

O3 is a secondary product of photochemical reactions. The relationship between reactants and products can be analyzed by monitoring the information regarding VOCS, NOX, and O3.

Confirmation Model Simulation

O3 formation and control are usually simulated using models in order to understand O3 problems in large areas. Information for VOCS not only provides initial values for model calculation but provides actual values that can be compared with simulation values. The model’s parameters can be adjusted and the predictions can be made more accurate. Lack of actual information can make simulations very uncertain and unsuitable for decision making.

Provides a Base for Policy Change

After receiving simulation results and experimental confirmation for photochemical reactions, control strategies can be formulated in different areas. With the assistance of actual test information, risk of inaccurate information is lowered, and this is the ultimate goal for data measurement. After a strategy is put into effect, actual observation data can be used to assess its effects. Therefore, information of VOCS and O3 is very valuable for evaluation of control strategies and necessary for O3 control.

Monitoring Poisonous Materials

Aside from controlling O3, PAMS are also able to detect some toxic substances in the air, such as benzene, toluene and so forth. Instantaneous tracking information for VOCS provides concentration data for many trace substances in the atmosphere and can be used to analyze the composition of pollutants and be a reference for pollution sources.

last update : 2019/11/27