We monitor air quality at a number of sites around the borough. There are two techniques used to monitor air quality:

1. Non-Automatic Sampling. Diffusion tubes located around the Borough sampling for Nitrogen Dioxide and Benzene.

2. Automatic Continuous Monitoring. Monitoring stations which report concentrations of carbon monoxide, nitrogen dioxide, ozone, sulphur dioxide and PM10 particulate matter automatically every hour of the day.

Automatic Monitoring Sites

Automatic monitoring stations

• Hillingdon 1 - South Ruislip
• Hillingdon 2 - Hillingdon Hospital
• London Hillingdon Oxford Avenue
• London Hillingdon
• London Hillingdon Harmondsworth
• London Hillingdon Harmondsworth Os
• Hillingdon Hayes
• Hillingdon Sipson

The map showing the locations of the automatic monitoring stations in the borough. Automatic monitors are especially useful for providing near real-time public information and warning people if air pollution is currently high. The air quality data section of this web site provides up-to-date graphs and reports of the latest air pollution levels and forecasts for the borough.

Air quality monitoring data from both automatic and non-automatic methods is an essential part of the process of air quality review and assessment. It provides the scientific background necessary to validate any modelling studies. This ensures that any conclusions reached are accurate and reliable indications of the pollutant concentrations found in the area.