London Borough of Hillingdon Monitoring Data
Hillingdon Harmondsworth (HIL1)
Latitude: 51.487989
Longitude: -0.480984
Longitude: -0.480984
Date Started: 01/07/2007
Environment: Urban Background
Environment: Urban Background
Latest Data
This monitoring site data was last updated: 15/12/2025 14:00
| Parameter | Pollution Band | Concentration | Period |
|---|---|---|---|
| Nitrogen dioxide (NO2) | Low (Index 1) | 26 µg/m3 | hourly mean |
| PM10 particulate matter (Hourly measured) | Low (Index 1) | 11 µg/m3 (Ref.eq) | 24 Hour mean |
| Nitric oxide (NO) | not applicable | 5 µg/m3 | hourly mean |
| Nitrogen oxides as nitrogen dioxide (NOx as NO2) | not applicable | 34 µg/m3 | hourly mean |
Note: Values are based on provisional data. Data are GMT hour ending.
PM10 is measured as a running 24 hour mean, up to the current hour, and the band/index is calculated accordingly.
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