2. Traffic Analysis
2.1 Traffic Composition
As it can be clearly seen from Figure 5 that the most
dominant type of traffic was passenger cars, which represented
the highest percentages (54-63%) of the total traffic volume at all
monitoring stations. Motorcycles represent the second largest
group, ranging between 17-28% of total traffic at most
observation stations. On the contrary, trucks and buses
represented the smallest group of vehicles representing only
about 10% of the total traffic. It is observed that passenger cars
and motorcycles exhibit higher percentages in total traffic
composition than other vehicle types, thus they will have
significant influence on the roadside pollutant concentrations