Background concentrations of NOX and NO (3 sites), PM10 (single
site) and CO (2 sites) within the CCZ all fell whilst NO2 and O3
concentrations rose at the three sites within the zone. These figures
contrast with small average increases in NOX, NO and NO2 monitored
at seven locations in the control area (0.6%, 1.1% and 0.2%
respectively) and average decreases in PM10 (0.8%) and O3 (6.8%)
measured at 5 and 3 monitoring stations respectively.