Tool 13 - Calculating Air Pollution Near Roads Using CAR-International Model
CAR International is a simple to use air quality dispersion model. This model has been developed by the Dutch Institute Environmental, Energy and Process Innovation (TNO) in cooperation with the Netherlands National Institute of Public Health and Environmental Protection (RIVM). Although CAR International is no longer supported, it is still helpful in calculating concentrations of a number of air pollutants such as:
The model, CAR International, is contained in this CD-ROM. Please read the instructions for installation and the guidance notes for CAR International.
Results of CAR International
The level of pollution of a given pollutant near roads is calculated
at a distance to the road axis ranging from 5 to 30 meters. The following
concentrations of the above-mentioned five pollutants can be calculated
with CAR International:
Average annual and peak concentrations of CO, NO2 and benzene can subsequently be compared with the (WHO) air quality guidelines in order to identify potential air pollution problems.
This version of the CAR International model requires Microsoft Windows
operating system (95, 98, 2000, XP).
The following window will open.
Table 13.1 Entry pages of Car International
The model is very easy to use, as long as the necessary parameters and input data are available. It requires few data, as follows:
Table 13.2 Factors That Users Can Change
Table 13.2 above presents those factors that users can change. These factors have been fixed based on an average Dutch situation. In case of developing countries, the factors have to be adopted locally, especially the emission factors.
The following tables give the necessary parameters that have to be fed
into the model in order to calculate the pollutant concentrations.
Given below are the specifications:
1. Speed Types: CAR International uses four speed types
2. Tree Factor: The tree factor represents the influence of trees on the dispersion of air pollutants. There are three options described as below:
3. Road Types: CAR International Distinguishes between five road types
Table 13.3 Results
The TNO Environmental Sciences developed the CAR International computer programme. For further information on this programme, please contact TNO-MEP, Department of Environmental Quality, P.O Box 6011, 2600 JA Delft, The Netherlands. Tel +31-15-2696035, fax +31-15- 2616812, Email: O.Weinhold@mep.tno.nl
The following example from Dar es Salaam is based on a speadsheet which uses the same parameters as the above model. Air pollution concentrations for five streets in Dar es Salaam are calculated: