During the negotiation of the EU Directive on Ambient Air Quality and Cleaner Air for Europe, DEFRA undertook a review of the automatic monitoring networks taking into account the requirements of the directive.
The changes to the Automatic Urban and Rural, and Hydrocarbons networks fall into three broad areas:
(i) A reduction in the number of carbon monoxide and sulphur dioxide monitors, commensurate with the generally low levels of both pollutants currently found. However, there will be increased sulphur dioxide monitoring in some areas around particular industrial hotspots.
(ii) Movement of oxides of nitrogen monitors from agglomerations to zones, and from urban background to roadside.
(iii) The creation of a PM2.5 network, and changes to the PM10 network. In addition to setting the minimum number of PM monitors to be operated, the directive specifies the ratio of PM10:PM2.5 and urban background: roadside sites which must be operated; in both cases this ratio must be between 2:1 and 1:2.
This will result in:
the closure or removal from the network of 20 complete sites
the opening or affiliation into the network of 33 new sites (mainly for PM10/PM2.5 and oxides of nitrogen)
the removal of 51 carbon monoxide analysers
the removal of 32 and the addition of five sulphur dioxide analysers
the movement and/or addition of 29 oxides of nitrogen sites
the addition of 67 PM2.5 sites
the movement and/or addition of 21 PM10 sites
the movement of 11 benzene sites
the removal of 13 and the addition of four ozone sites
To date the following have been completed:
the closure or removal from the network of 20 complete sites (from 1 October 2007).
the dissemination of data from 51 carbon monoxide and 32 sulphur dioxide sites stopped on 1 October 2007.
the addition of 17 local authority sites into the network; a further five sites will be brought into the network during May/June. For the remaining sites, work is ongoing to identify suitable local authority sites to bring into the network.
the purchase of type approved gaseous analysers for DEFRA-owned sites to replace existing non-type approved equipment. These analysers will be installed during routine site visits during 2008.
the installation of 22 reference method equivalent PM10 analysers and the procurement of 11 PM2.5 analysers.
an OJEU notice has been published to procure the remainder of the particulate matter analysers.