Camden Air Quality Monitoring

This interactive page provides information about Camden’s air quality monitors, enabling you to view their locations and the data they collect.

Improving air quality is a key priority for Camden. You can read more about what we are doing to reduce air pollution and how you can help on our air quality web pages.

Monitor types and data

We monitor air pollution levels at many sites across Camden. We choose sites which are representative of public exposure to air pollution. The following air pollutants are monitored:
  • nitrogen dioxide (NO2) and nitrogen oxides (NOX)
  • particulate matter (PM10/PM2.5)
  • sulphur dioxide (SO2)
  • ozone (O3)
  • carbon monoxide (CO)
Air pollution levels are monitored using a number of different instruments. Some of these are very basic pieces of equipment, while others use complex technology. Data from the monitoring stations are collected and uploaded online hourly, daily and monthly depending on the type of system.
Automatic monitoring stations
Camden has five automatic monitoring stations located across the borough. These are permanent installations which contain sophisticated electronic instruments to measure a variety of pollutants. Data is transmitted every 15 minutes to a central management system which is then automatically uploaded to the LondonAir website, where you can find data for all five stations, create graphs and download raw data.  This monitoring network is maintained by King's College London on behalf of the Greater London Authority.
To view a graph of the pollutant levels over the past seven days for each site, please click on the location links below.
Automatic monitoring station data: long-term trends in air quality
The graphs below show annual mean concentrations of NO2, PM10 and PM2.5 measured by the five automatic air quality monitoring stations in Camden, from 2014 until the most recent year for which full ratified data is available.
Diffusion tube monitors
Diffusion tubes monitor long-term trends of NO2 concentrations and we have 19 sites located across Camden which we use for statutory annual air quality reporting. The tubes are typically mounted on lampposts or buildings and are collected every four weeks and sent to a laboratory for analysis, and the data is then uploaded to this website. Although the tubes cannot be used to provide up-to-the-minute pollution levels, they are easy to use and provide helpful complementary background data to the automatic monitors. 
In addition to the 19 monitoring sites that we use for statutory annual reporting, we also have 114 diffusion tube sites which are used for air quality monitoring for transport projects, and a further 10 diffusion tube sites in a community-led monitoring project in Belsize Park and Swiss Cottage.
The below charts display monthly data for each year measured since 2015 for the 19 sites used for statutory annual reporting, as well as 13 sites which form part of the air quality monitoring for the Camden Town Low Emission Neighbourhood (LEN).
Please note each month is numbered to ensure the graph generates in the correct date order. Occasionally results can be compromised due to foreign objects or water droplets in the tube. The methodology recommended in the London Local Air Quality Management Technical Guidance has been applied to fill in any missing data from 2017 onwards, in order to ensure full data coverage.
A note on using diffusion tube data
Individual month-average NO2 concentrations should not be compared directly: a variety of local and environmental factors influence pollutant concentrations and it is advisable to consider the annual mean NO2 concentration which is calculated after taking into account any necessary seasonal or analytical adjustment factors. Month-average NO2 concentration instead provides an indication of seasonal changes.
Please also note that diffusion tube data will not be available for up to three months after the monitoring period due to the duration of the analytical process.

2019 - Monthly NO2 levels by location
2018 - Monthly NO2 levels by location
2017 - Monthly NO2 levels by location
2016 - Monthly NO2 levels by location
2015 - Monthly NO2 levels by location
Community air quality monitoring
Camden’s air quality monitors are located in specific areas across the borough, however we cannot monitor at all locations. We therefore invited residents and community groups to apply for free diffusion tube equipment to monitor their own areas for three to nine months between July 2017 and March 2018.
23 monitoring projects were carried out across Camden in 47 different locations, the results of which are shown below. For approximate locations of the monitors please see the map further down the page.
Please note, the graph below contains the raw diffusion tube data which has not undergone any validation processes, and therefore cannot be considered in comparison to air quality objectives or in the production of air quality assessments.
Please note, if no data is displayed the diffusion tube may have been lost or damaged, or the site was not monitoring that chosen month.

AQ Mesh monitors
Our AQ Mesh monitors are small portable units that measure concentrations of NO2, PM10 and PM2.5 in the air. We have six units which, like our diffusion tubes, are located on lampposts and buildings and are used to monitor specific projects in a number of locations across the borough.
Data is transmitted every hour from the AQ Mesh units directly to a central hub, which is then uploaded on this website every 24 hours.
The below graph shows NO2 levels over the past seven days for each AQ Mesh site, displaying the hourly average of data recorded every 15 minutes.  You can also view, explore and download the information for this graph on the background data page.

NO2 measurements by site location (last 7 days)

PM10 measurements by site location (last 7 days) - not all monitors can capture NO2
AQ Mesh monitors are not certified as 'reference equivalent' analysers, and the data must therefore be considered as suggestive rather than providing a precise measure of pollutant concentrations.


The below map outlines the approximate locations of the 19 statutory diffusion tubes, 13 Camden Town LEN diffusion tubes, five automatic monitoring stations and six AQ Mesh monitors across Camden, which can be zoomed in and out using the tool on the left.

External monitoring data

High Speed 2 Ltd (HS2) is monitoring baseline air quality levels at a number of sites around Camden. You can view this data by clicking the links provided at the bottom of the following page:
You can learn more about our assurances with HS2 and how we are working to minimise and mitigate as far as possible the adverse impacts of the scheme on Camden.
Breathe London is a collaborative London-wide project to use real-time sensors in building a more detailed picture of air quality throughout London. The GLA, Environmental Defense Fund Europe and Air Monitors have worked with Camden and the other boroughs to install an additional 100 AQ Mesh monitors which will be used to assess pollution hotspots and to analyse the impact of traffic, weather and other conditions on pollution levels.
You can find out more on the Breathe London website.

More information

For further information on Camden’s air quality programme, including what we are doing and how you can get involved, please click here.
To sign up for free air quality alerts and forecasts from airTEXT, please visit the sign-up page of the airTEXT website.