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Air quality in West Lancs

Our Environmental Protection team check the borough for eight key pollutants which can affect health in the long or short term. These are:

  • Nitrogen dioxide - associated with vehicle exhausts, combustion processes and some industrial processes 
  • Sulphur dioxide - mostly from the combustion of oil and solid fuel, but also from diesel vehicles 
  • Carbon monoxide - from vehicle exhausts and poorly operated boiler plant particles 
  • Very fine particles emitted from vehicle exhausts, combustion processes and industrial sources. Usually referred to as 'PM10' - particles less than 10 microns in diameter. A micron is a thousandth of a millimetre. 
  • Benzene - an organic chemical emitted in exhausts and also during refuelling. 
  • 1,3-Butadiene - another organic chemical emitted in exhausts and also from some industrial processes 
  • Lead - mostly from leaded petrol 
  • Ozone

Nitrogen dioxide air quality monitoring

We primarily monitor the air quality in West Lancashire for nitrogen dioxide, which is one of the main pollutants in the air that we breathe.

Nitrogen dioxide enters the atmosphere mainly through traffic fumes and for this reason monitoring has been targeted in areas where traffic flows are high or standing traffic is predominant.

The Government has set a target limit of 40ug/m3 as an annual average for nitrogen dioxide levels.

The method used to measure Nitrogen Dioxide levels is through the use of diffusion tubes. These tubes work on the principal of diffusion of high concentrations of pollutant at the open end of the tube to low concentration at the closed end where an absorbent chemical is located to collect the Nitrogen Dioxide. The tubes are changed at monthly intervals and sent to a laboratory for analysis and reporting of results.