Heathrow Airwatch uses cookies to make the site simpler. Find out more about this

Latest air quality summary

Number of monitoring sites in each pollution band

Heathrow Airwatch was last updated at 12:00 on Saturday 21st July 2018

  • Low23
  • Moderate0
  • High0
  • Very High0
  • No Data2
  • 25

    Total monitoring sites

Green Low (1-3) Orange Moderate (4-6) Red High (7-9) Purple Very High (10)
Grey Offline | Find out more about the air pollution index and bandings

« Return to site summary list

Hounslow 4 - Chiswick High Road

Maximum pollution level at this monitoring site is Index 2
Parameter Pollution Band Concentration Period
PM2.5 Particulate matter (PM2.5)
Updated: 21/07/2018 10:00 		Low (Index 2) 19 µg/m3 (BAM) 24 Hour mean
PM10 Particulate matter (PM10)
Updated: 21/07/2018 10:00 		Low (Index 2) 25 µg/m3 (VCM) 24 Hour mean
Oxides of Nitrogen (NOXasNO2)
Updated: 21/07/2018 10:00 		not applicable 49 µg/m3 hourly mean
Nitrogen dioxide (NO2)
Updated: 21/07/2018 10:00 		Low (Index 1) 32 µg/m3 hourly mean
Nitric Oxide (NO)
Updated: 21/07/2018 10:00 		not applicable 11 µg/m3 hourly mean

Note: These results are based on provisional data. The data are presented in graphical form based on the highest pollutant measured at each site.