Maximum running 8-hour CO concentrations in all background locations in 2004 are predicted to be well within the proposed limit value of 8.59 ppm.

Estimated roadside CO concentrations in 2004 are expected to be higher. For typical meteorology, the predictions show that no road links are expected to have concentrations higher than 8.59 ppm by 2004 and only 2 are expected to have concentrations greater than the proposed limit value by 2002. For extreme meteorology, such as that experienced in some UK cities in 1991, the predictions show that one road link is expected to have a concentration higher than 8.59 ppm by 2004 and only 14 are expected to have concentrations greater than the proposed limit value by 2002.

Chapter 5         Chapter 7