Monitoring and predicting air pollution

The Mayor of London, Sadiq Khan, announced on 30 January 2018 that he is teaming up with Imperial College London to improve the way he informs the public, particularly those who are most vulnerable, about incidents of poor air quality in the capital.

Imperial College London will directly notify schools, and potentially care homes, and GPs' surgeries soon of moderate, high and very high pollution episodes.

The Mayor is also making it easier for all Londoners, including schools and community groups to take a more active role in fighting pollution. Personal and relatively low-cost monitoring systems are becoming more accessible to buy. These can be valuable tools, but knowing how best to use the systems is vital if the results are to provide meaningful information.

Read more in our new monitoring guidance report.

London’s air quality is constantly monitored at around 100 different locations. These sites are operated and funded by London boroughs.

• the London Air website of Imperial College London records real time and historical monitoring data
• Ricardo Energy and Environment also manages the data sets from some sites within London, more information is on the Air Quality England website

Despite cuts in most pollutants, levels of PM10 and NO2 are still too high in some areas of London. We are working hard to reduce concentrations of these pollutants. However, around 30-40% of air pollution comes from outside Greater London.

Between 3 and 8 times a year, London’s air pollution is particularly high. On these days, you can protect yourself and others by avoiding the car and using back streets to walk and cycle instead.

Transport for London (TfL) now broadcasts air quality advice across London whenever pollution is high or very high. You will see notifications at Tube stations, bus stops, river piers, on digital signs along major roads. Information is also published on the TfL website.

• Sign up for free pollution alerts on the airTEXT website
• See air quality updates on London Air

The Mayor of London, Sadiq Khan and the Mayor of Bengaluru in India, Sampath Raj, announced on 5 December 2017 that they will lead a global partnership of up to 20 other world cities on tackling global air pollution. The initiative will be delivered by the C40 Climate Leadership Group as part of its new Air Quality Network programme.



London’s “Breathe London” network is a major £750,000 trail cutting-edge street-by-street sensor air quality monitoring system which will be used to analyse harmful pollution in thousands of toxic hotspots across the city including near schools, hospitals, construction sites and busy roads. This data will support policy making, and help inform and engage local communities.



Find out more and see the latest data from the network on the Breathe London website.