C27283_NOx Gas Analysers STA 2024 -2025

The AURN is the UK's largest automatic monitoring network and is the main network used for compliance reporting against the Ambient Air Quality Directives. It includes automatic air quality monitoring stations measuring oxides of nitrogen (NOx), sulphur dioxide (SO2), ozone (O3), carbon monoxide (CO) and particles (PM10, PM2.5). These sites provide high resolution hourly information. Further details of the current network are available on http://uk-air.defra.gov.uk The Environment Agency on behalf of the Department for Environment, Food and Rural Affairs (Defra), Affiliated Local Authorities and Devolved Administrations is seeking to procure gas analysers to measure the following gases: oxides of nitrogen (NOX), nitrogen dioxide (NO2), ozone (O3) and sulphur dioxide (SO2). The gas analysers will in general be used on the UK's largest Air Quality Monitoring Network the AURN and the associated Automatic London Network (ALN).

The Environment Agency reserves the right to use the instruments for other Air Quality Monitoring activities.

The Environment Agency manages and maintains the AURN and ALN, which monitors air quality across the UK. The gas analysers are managed by the Central Management and Control Units (CMCU) (further defined below) and it has been indicated that a number of replacements are required due to the equipment having a critical parts failure, becoming damaged, not producing data of sufficient quality, reaching the end of life, or not having sufficient available spare parts from the manufacturer.