Air Quality Monitoring
Air quality in Hambleton is measured using two methods - real time and passive.
Real time monitoring - the air quality is measured automatically 24 hours a day, 365 days of the year using the Air Quality Monitoring Station (AQMS) at one location in the district. The AQMS houses two separate analysers, one monitors nitrogen dioxide and the other monitors particulate matter. The data is recorded in a data logger where it is held until the information is downloaded by computer to the Council offices.
Passive monitoring - this is carried out using diffusion tubes located across the district. These monitor nitrogen dioxide on a monthly basis.
What are Diffusion Tubes?
A diffusion tube is a small plastic tube which monitors ambient air quality, giving a monthly average. The tube is open at one end during the exposure period and works on the basis of molecular diffusion moving with an absorbent at the sealed and of the tube. After the exposure period the tube is analysed at an independent laboratory and the results sent to the Council.
What is the Air Quality Monitoring Station?
The Air Quality Monitoring Station (AQMS) is a mobile laboratory that samples, analyses and records air quality information automatically. The AQMS can be moved from one site to another so that air quality can be monitored at different locations around the district. However, the AQMS is generally left in each place for about a year so that the influences of the weather and traffic levels can be taken into account when analysing the results.
