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 02:00 on Monday 23rd April 2018

  • Low9
  • Moderate0
  • High0
  • Very High0
  • No Data16
  • 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

London Hillingdon Harmondsworth Os

Maximum pollution level at this monitoring site is Index 2
Parameter Pollution Band Concentration Period
PM2.5 Particulate matter (PM2.5)
Updated: 22/04/2018 06:00 		Low (Index 1) 8 µg/m3 (Osiris) 24 Hour mean
PM10 Particulate matter (PM10)
Updated: 22/04/2018 06:00 		Low (Index 2) 25 µg/m3 (INDIC GRAV) 24 Hour 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.