Air Quality Monitoring Stations (AQMS)
In 2022 there were two continuous automatic Air Quality Monitoring Stations (AQMS) in the borough of Hammersmith & Fulham that provide real-time 24 hours a day air quality monitoring data. They are Shepherds Bush Green (HF4) and Hammersmith Town Centre (HF5) that are both roadside Air Quality Monitoring Sites. Further information can be found on the Air Quality England website.
The AQMS contains reference compliant equipment that continuously monitors and measures the Main health impacting Air Pollutants Nitrogen Dioxide (NO2), Particulates (PM2.5, PM10) and Ozone (O3) in a roadside cabinet (See below). The term ‘reference’ is applied to instruments which have demonstrated compliance with Defra’s minimum performance requirements and data quality objectives.
As part of the Clean Air Neighbourhood programme four new Air Quality Monitoring Stations have been installed in 2023 at roadside and urban background sites across the borough (See map below). They are
- Fulham Town Centre (HF6) - Roadside
- Riverwalk (Frank Banfield Park) (HF7) - Urban Background
- Wormwood Scrubs (Du Cane Road) (HF8) - Roadside
- Sands End (Philpot Square) (HF9) - Roadside
Roadside Sites (within 1 – 5m of a busy Road) give a better idea of public exposure. Roadside sites are useful for identifying potential health hazards from traffic hotspots - especially those frequented by large numbers of pedestrians.
Background sites (more than 10m away from a main road) should not be dominated by one single nearby pollution source. They are located more than 10m away from a main road and 5 m away from anywhere vehicles stop with their engines idling. Quiet roads within residential areas, schools and other public buildings can be used as background sites if open space such as parks are not available.
Wormwood Scrubs Air Quality Monitoring Station (HF8)
2. Air Quality Sensor Networks
For the last few decades, most air quality monitoring around the world has been undertaken by central or local governments using reference-grade instruments. These reference networks have served as the foundation stone for research, policy development, health impact analysis and continue to play a vital role in our understanding of air quality.
Though this new generation of small automatic Air Quality sensors are improving and provide 24 hour data collection none of them have yet achieved ‘reference equivalent’ status. Instead, these sensors are assessed against a standard known as ‘indicative’.
Breathe London Air Quality Sensors
The Breathe London network is run by the Environmental Research Group at Imperial College London - the same group who run the London Air Quality Network. All Breathe London Air Quality Sensors are co-located with London Air reference air quality monitors before being deployed.
A total of 57 breathe London Air Quality sensors have been installed across the borough during 2021-2023. These Air Quality Sensors are powered by solar panels and have been installed on lampposts at a height of between 2.5 - 3 metres.
As part of the Clean Air Neighbourhood Programme 47 of these Air Quality Sensors have been installed near the student entrances of Primary, Nursery and Secondary Schools across Hammersmith & Fulham. These locations were selected to monitor the impact of the Clean Air Neighbourhood Programme on the concentrations of the health impacting air pollutants NO2 and PM2.5 near to Schools. (See map below)
Breathe London Air Quality Sensor installed at Langford Primary School
There are also Breathe London Air Quality sensors installed near Charing Cross Hospital and Old Oak, White City and Edward Woods Community Centres as part of the Breathe London Community Programme.
The data from these Breathe London Air Quality Sensors is freely available to the public on the Breathe London website.
3. Nitrogen Dioxide (NO2) Diffusion Tube Network
There are currently non-automatic NO2 Diffusion Monitors installed at 56 locations across the borough (See Map below).
A diffusion tube is essentially a small plastic test tube that contain a material that reacts with NO2 in the air. Diffusion tubes is used by the council to complement automatic monitoring data. They are a cheap and effective tool for measuring nitrogen dioxide (NO2). Each tube costs less than £10 including analysis afterwards. Diffusion tubes are prepared by a laboratory, used in the measurement study and then returned for analysis. The NO2 diffusion Tube Monitors are usually installed on lampposts in H&F at a typical breathing height of between 2.0-3.0 m.
The tubes are clear plastic with rubber stoppers at each end. They contain a steel mesh coated with a chemical which absorbs NO2. When the tube is opened (by removing one of the rubber stoppers) the coated steel mesh is exposed to the air and absorbs NO2.
As NO2 concentrations vary by season it is recommended diffusion tube monitoring programmes span a full year (that is twelve 4–5-week exposures).