Figure 2

PM 10 values within the Environmental Zone in different vehicle conditions and levels of significance. Position of measurements within 15 intervals each of approximately 28 minutes between 10 a.m. and 5p.m.;RO = roof open, RCWO = roof closed and window open, RCWC = roof closed and window closed. a-c: direction West to East, d-f: direction East to West. Geographical picture by Google Earth