Determining the traffic contribution to air pollution of Tehran mega city and technological necessities for its improvement

Air pollution in Tehran has a systematic behavior, and its inputs and outputs are specified. It is an example of a complex system considering the number of parameters and the importance of consequences, mutual influence of the factors, the variety of tactics, and the difficulty of measuring and monitoring the related variables. In this paper, the main reasons of Tehran air pollution, and the estimation of each pollution source contribution including traffic in creating the main pollutants are surveyed. This is done by a cause and effect diagram (fishbone diagram), using experts’ survey, and weighting method considering the type and intensity of air pollution consequences. In next section of the paper, taking into account the high contribution of traffic to air pollution, technological necessities including infrastructural, hardware, software, social and cultural ones are proposed for reducing the capital traffic and controlling the traffic indices within the related standard. The most important traffic indices are mentioned and their quantities in Tehran during the years 1384 and 1390 are presented. The quantities analysis shows an estimation of the effectiveness and efficiency of the results to improve the traffic during the above mentioned years. Air pollution and heavy traffic (especially in peak times) are the problems of many mega cities and provincial capitals of the country besides Tehran. Therefore, the results of this paper can be used as a pattern by them.