Nitrogen dioxide and benzene were monitored using passive diffusion tubes. For nitrogen dioxide four different tubes were used at each site. Tables 5 and 6 show the results. Although some differences in concentrations were observed, changes are not regarded as significant and were possibly affected more by changes in meteorology than changes in traffic flow and speed. Twelve-hour directional counts were carried out at four junction locations during the before survey, and three junction location during the after period.
Results show a fall in pedestrian flows throughout the periods of the counts.
There was no clear indication as to the reasons for this, but in part it may have been due to pedestrians crossing away from the junctions because of improved conditions along the roads following zone implementation. The zone appears to have had little effect on cycling. There was a small decrease between the before and the 3 month after survey. However, the 12 month after survey showed a similar number of cyclists entering to that recorded in the before data. However, a large minority considered that speeds had either not changed or had increased.