Of the three types of atmospheric pollution (thermal, vehicular, industrial), the first two are those largely responsible for the change that takes place in the composition of the low-lying urban air strata. Vehicular emissions play a big role in low altitude urban pollution. A phenomenon of this type, particularly when the town topography is considered to be of the 'closed' type, tends to concentrate vehicular emissions for a long time. In this report specific vehicle-generated pollutants are considerably diversified, qualitatively and quantitatively. The tests that are given here, have great practical importance. In fact, an investigation of the type described in the document can be made by using a setup that would include even more equipment because the cost of the sampler is low, and the sampler is very easy to operate. Interpretation of the data obtained by the samplers leads to the conclusion that pollution is heaviest at the low levels (to about 3 meters) during rush hours. At slightly higher levels (6 meters for the case in point), the mean pollution level tends to decrease, though remaining constant.