Topic 2c - Part 1: Street level sensing – the role of ultra-local monitoring

Many urban areas around the world have local street level air quality monitoring. The City of London Corporation has been monitoring air quality in the Square Mile since the 1960s, after the Clean Air Act was introduced, monitoring sulphur dioxide and black smoke. Since 2001 the City has been an Air Quality Management Area for nitrogen dioxide (NO2) and fine particles (PM10), so monitoring now focuses on these pollutants.

Ground sensors in the City of London include 60 ‘diffusion tubes’ which monitor nitrogen dioxide, and continuous analysers, at 5 locations, which monitor one or more of NO2, PM10 and PM2.5 24 hours a day. The London Air Quality Network (LAQN), run by King’s College London, monitors air pollution in the whole of Greater London, and was formed in 1993. This covers over 100 continuous monitoring sites in the majority of London’s 33 boroughs.

Data from LAQN this year has shown that Brixton Road has become the first place in London to breach objectives for nitrogen dioxide (NO2) for 2018. However NO2 has considerable decreased in concentrations along Putney High Street, Brixton Road and Oxford Street over the last two years. This is likely due to a combination of better real-world emissions performance of the latest heavy goods vehicles and upgrades to London’s bus fleet. There have been a number of air quality legislation in London that has been recently implemented or will be in the near future. These are:

  • London Toxicity Charge (T-Charge)

  • Ultra Low Emission Zone (ULEZ)

  • Clean Vehicle Checker

  • London Taxis

  • London Buses

Featured Educator:

  • Dr David Green

Don’t forget you can download the video, transcript and take any quizzes available with the links on the right.

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Air quality monitoring station - London Haringey

The monitoring station is located within the grounds of Priory park, in the London Borough of Haringey. It is operated by King’s College London.

Air Pollution monitoring station - Camden

An air pollution monitoring station on Shaftesbury Avenue, in the London Borough of Camden.