There is a high level of uncertainty in government’s model for assessing pollution levels, which may mean that further areas of poor air quality might be missed by the programme. Government uses a national model to identify areas that are likely to be breaching air quality limits, and uses this to direct local authorities to take action. The national model does not directly use the results of monitoring by local authorities; instead, it uses a national network of monitoring stations. The mode...

There is a high level of uncertainty in government’s model for assessing pollution levels, which may mean that further areas of poor air quality might be missed by the programme. Government uses a national model to identify areas that are likely to be breaching air quality limits, and uses this to direct local authorities to take action. The national model does not directly use the results of monitoring by local authorities; instead, it uses a national network of monitoring stations. The model is regularly updated to take account of differences to local modelling, however government estimates that overall uncertainty in the model remains at t Type: recommendation | Number: 2 | Response status: accepted Government response: The government agrees with the Committee’s recommendation Recommendation implemented The government is satisfied that the best available evidence that meets the stringent requirements for assessing compliance with the annual mean Nitrogen Dioxide (NO ) limit value