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What do the air quality bands mean?

In the UK, most air pollution information services use the index and banding system approved by the Committee on Medical Effects of Air Pollutants (COMEAP). This index is designed to advise about short term health effects only. Because of this, it is possible for a pollutant at a site to have a low short term index every day and yet fail an air quality standard which is based on long term health effects.

The system index has 4 bands indicating the degree of air pollution and the health risk.

To use the index follow the following three steps:

  1. Step 1. Determine whether you (or your children) are likely to be at-risk from air pollution. Information on groups who may be affected is on the ‘Additional information on the effects of air pollution’ page. Your doctor may also be able to give you advice.
  2. Step 2. If you may be at-risk, and are planning strenuous activity outdoors, check the air pollution forecast.
  3. Step 3. Use the health messages corresponding to the highest forecast level of pollution as a guide.