Air quality

What are you breathing?

Defra runs about 170 monitoring stations that measure the air every hour. This page finds the ones nearest your postcode and shows what they are reading now: nitrogen dioxide, fine and coarse particles, ozone and sulphur dioxide, each on the Daily Air Quality Index scale, with the last two days at the nearest station and the index's advice.

  • Measured, not modelled
  • Index bands per pollutant
  • The last 48 hours

How this works

The Automatic Urban and Rural Network and its partner networks report hourly to Defra’s UK-AIR service, which publishes every station’s latest reading through a Sensor Observation Service. The page reads that list, cached for an hour, works out which reporting stations are within 40 km of your postcode, and fetches the last two days for each pollutant at the nearest one so that particles and ozone can be judged on the daily and eight-hour means the Daily Air Quality Index uses. Stations that have not reported for six hours are left out. The dashboard’s air quality panel uses a modelled forecast instead; this page is what the instruments actually measured.

Sources

  • Defra UK-AIR Sensor Observation Service. © Crown copyright Defra via uk-air.defra.gov.uk, licenced under the Open Government Licence (OGL).
  • Postcodes: postcodes.io / ONS Postcode Directory (OGL v3).

For information only. Readings are provisional until ratified and a station’s surroundings decide what it sees.