Air Quality & Noise Monitoring Program

Health impacts

The Daily Air Quality Index (DAQI) tells you about levels of air pollution and provides recommended actions and health advice. The index is numbered 1-10 and divided into four bands, low (1) to very high (10), to provide detail about air pollution levels in a simple way, similar to the sun index or pollen index.

More information about the Daily Air Quality Index is available from UK-AIR website.

The overall air pollution index for a site or region is determined by the highest concentration of five pollutants:

  • Nitrogen Dioxide
  • Sulphur Dioxide
  • Ozone
  • Particles < 2.5µm (PM2.5)
  • Particles < 10µm (PM10)

How to use the Daily Air Quality Index

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 provided on the Additional information on the short-term effects of air pollution page. Your doctor may also be able to give you advice.
Step 2: If you may be at-risk, and are planning strenuous activity outdoors, check the air pollution forecast.
Step 3: Use the health messages corresponding to the highest forecast level of pollution as a guide.

Air Pollution Banding Value

Accompanying health messages
for at-risk individuals*

Accompanying health messages for the general population
Low 1-3 Enjoy your usual outdoor activities. Enjoy your usual outdoor activities.
Moderate 4-6 Adults and children with lung problems, and adults with heart problems, who experience symptoms, should consider reducing strenuous physical activity, particularly outdoors. Enjoy your usual outdoor activities.
High 7-9 Adults and children with lung problems, and adults with heart problems, should reduce strenuous physical exertion, particularly outdoors, and particularly if they experience symptoms. People with asthma may find they need to use their reliever inhaler more often. Older people should also reduce physical exertion. Anyone experiencing discomfort such as sore eyes, cough or sore throat should consider reducing activity, particularly outdoors.
Very High 10 Adults and children with lung problems, adults with heart problems, and older people, should avoid strenuous physical activity. People with asthma may find they need to use their reliever inhaler more often. Reduce physical exertion, particularly outdoors, especially if you experience symptoms such as cough or sore throat.

*Adults and children with heart or lung problems are at greater risk of symptoms. Follow your doctor's usual advice about exercising and managing your condition. It is possible that very sensitive individuals may experience health effects even on Low air pollution days. Anyone experiencing symptoms should follow the guidance provided above.