Air Quality in Weymouth and Portland
Air quality across Weymouth and Portland is reviewed annually against the National Air Quality Standards set by the Government. You can view the annual reports from the latest round of review and assessment below:
Air pollution can affect human health as well as the natural environment and buildings. Air is made up from nitrogen, oxygen, argon and traces of carbon dioxide, hydrogen and other gases. This balance can be affected by our activities and when it is altered the environment can then be considered to be 'polluted'.
The Environment Act 1995 requires local authorities to review air quality having regard to the relevant regulations made under the Act. This is known as Local Air Quality Management (LAQM). It means identification of pollutant hotspots where members of the public may be exposed to proposed exceedances of specific air quality objectives and looking to improve things.
National objectives are given in regulations (Air Quality Regulations 2000) for seven pollutants.
Environmental Health have been actively reviewing the air quality within the borough for some years now. We monitor levels of nitrogen dioxide (NO2) at 12 sites throughout the borough and particulates (PM10) at one location. The remainder of the pollutants for which objectives have been set have previously been identified to be well within the limit values. We regularly assess the industry within the borough and assess emissions to air, allowing us to decide to change our monitoring programme if we identify a change in circumstances.
The results obtained for nitrogen dioxide are recorded to assess whether the objectives are likely to be met, or if local levels are reducing. We have a database which is regularly updated. The results are also sent to be added to data held by DEFRA which looks at the trends and variation of concentrations throughout the country.
We use the following methods to monitor for nitrogen dioxide and particulates.
1. Passive method - diffusion tubes
A cheap and easy to use method to provide an average concentration of nitrogen dioxide over a four or five week period. Very useful for identifying areas of concern which then allows us to consider if further in-depth monitoring is required. There are approximately 14 diffusion tubes located throughout the borough. View a summary of Weymouth and Portland's monitoring results from our Nitrogen Dioxide Diffusion Tube Survey.
2. Automatic monitoring method (NO2) (chemiluminescence)
This is a 'real-time' way of measuring nitrogen dioxide. The analyser constantly draws air and measures NO2. Results are compared to co-located diffusion tubes, so a factor of how much the tubes are over or under-reading is calculated and then applied to our other tubes. This analyser is located to the Boot Hill (Rodwell Road) area of Weymouth.
3. Automatic monitoring - particulates (PM10) TEOM FDMS
There is considered to be a correlation between NO2 and PM10. The council were fortunate to make a successful grant bid to DEFRA to enable the purchase of this real-time analyser. Located to Boot Hill (Rodwell Road area) it sits with the NO2 analyser.