London Borough of Westminster Monitoring Data
London Marylebone Road (MY1, an AURN site)
Latitude: 51.522530
Longitude: -0.154611
Date Started: 01/01/1997
Longitude: -0.154611
Date Started: 01/01/1997
Altitude: 35 metres
Inlet Height: 3.5 metres
Environment: Kerbside
Inlet Height: 3.5 metres
Environment: Kerbside
Latest Data
This monitoring site data was last updated: 05/05/2026 15:00
| Parameter | Pollution Band | Concentration | Period |
|---|---|---|---|
| Ozone (O3) | Low (Index 3) | 75 µg/m3 | 8 Hour mean |
| PM10 particulate matter (Hourly measured) | No Data | 24 Hour mean | |
| PM2.5 particulate matter (Hourly measured) | No Data | 24 Hour mean | |
| Sulphur dioxide (SO2) | Low (Index 1) | 3 µg/m3 | 15 Minute mean |
| Nitrogen dioxide (NO2) | Low (Index 1) | 14 µg/m3 | hourly mean |
| Nitric oxide (NO) | not applicable | 4 µg/m3 | hourly mean |
| Nitrogen oxides as nitrogen dioxide (NOx as NO2) | not applicable | 19 µg/m3 | hourly mean |
| Carbon monoxide (CO) | not applicable | 0.2 mg/m3 | 8 Hour 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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