National Physical Laboratory

Monitoring emissions for improved air quality

The National Physical Laboratory (NPL) has played a key role in monitoring emissions, ensuring cleaner air for the UK and beyond.

The Challenge

Blue sky

In the mid 1990s it was clear that an accreditation scheme was required for continuous emissions monitoring. The drivers for this came from industry, the Environment Agency, UK Government and the international community.

The Solution

In 1998 the Environment Agency, with NPL's input, established a rigorous certification scheme (MCERTS) for pollution monitoring equipment, based on internationally-accepted performance standards. The MCERTS scheme initially focused on continuous emission monitoring systems.

In 1999 NPL became the first laboratory to test continuous emission monitors, which measure the gaseous pollutant concentrations within chimney stacks. This meant that certified instruments provided regulators and industry with the best basis with which to monitor releases from industrial processes.

NPL now has a dedicated suite of test and calibration facilities for carrying out instrument tests to the MCERTS standards. These include a variable temperature test cell that can produce accurate concentrations of stack gases and water vapour in simulated stack conditions, and an environmental chamber for testing those parts of the monitoring system exposed to outdoor conditions.

NPL also provides assistance and advice to companies so that they have the confidence of joining the scheme. NPL, based in Teddington, south-west London, is ideally placed to help companies who require assistance in the UK.

The Legacy

The MCERTS scheme, operated by Sira Environmental Ltd, on behalf of the Environment Agency, has evolved to cover a number of other areas of environmental monitoring. These include continuous ambient air monitoring systems (CAMS), portable emissions monitoring equipment and continuous water monitoring equipment (CWMS). The scheme now also provides personnel certification for manual stack emission monitoring and also effluent flow monitoring inspection.

MCERTS is now recognised across Europe and arrangements have been agreed with countries like Germany to ensure that it links together with their environmental monitoring processes.

NPL has been involved in MCERTS from the outset and still plays a lead role in writing the standards used for the approval of instruments as well as assisting instrument makers in developing instruments that will achieve approval. NPL's involvement helps to reduce costs to industry, promotes exports and plays a crucial part in achieving a cleaner environment.

The Impact

The scheme and NPL's role in it helps promote public confidence in monitoring data and provides industry with a proven framework for choosing monitoring systems and services that meet the Environment Agency's performance requirements.

For information, please contact Heather Powell

Find out more about NPL's MCERTS offering

Find out more about NPL's work in Environmental Measurement

Last Updated: 7 Jan 2013
Created: 22 Dec 2010


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