The main objective of this project is to determine whether changes to emission standards from 1992 to the present day have had a corresponding effect on roadside air quality.
Conclusions are to be based on measurements taken from the existing network of the Highways Agency's air quality monitoring stations, both from this contract and the earlier contracts.
The contractor was required to provide a written report containing analyses of the data collected in this and the previous air quality monitoring contracts. These analyses will assist in providing relationships between the air quality monitoring data collected and the changes in standards.
The contractor collected air quality monitoring data from the following four sites: M4 Theale, M25 Staines, M60 Kirkhams and A40 Cheltenham.
Pollutants monitored at some or all of the sites include NOx, CO, PM10, PM2.5, O3, NMHC, CH4, THC, H2S, SO2, PAH, BTEX and carbonyls. Traffic and meteorological data was also collected.