MCERTS: Tougher policing, better technology
29 May 2007
The Environment Agency has implemented increased levels of policing of the scheme by both UKAS and the Environment Agency, Jeff Ruddle, accreditation manager for UKAS (United Kingdom Accreditation Service) said at the event held 25-26 April at the Bretby Conference Centre. This, he said, includes the introduction of unannounced visits to assess compliance with the MCERTS standard.
Ruddle pointed out that UKAS is the sole national accreditation body able to assess, against internationally agreed standards, organisations that provide certification, testing, inspection and calibration services. This includes organisations that provide stack testing and monitoring services.
UKAS uses ISO/IEC 17025 -- General requirements for the competence of testing and calibration laboratories-- for its assessments. This standard includes the requirements that testing and calibration laboratories must meet to demonstrate that they operate a quality system, are technically competent and produce technically valid results. MCERTS is an elaboration of this generic accreditation.
Rod Robinson from NPL opened MCERTS 2007 with a presentation entitled ‘FTIR for Emissions Monitoring Applications’. He explained that FTIR is a powerful technique offering simultaneous analysis of multiple compounds through the provision of a complete spectral measurement, but warned that care is needed in its application, whether as a continuous emission monitoring system (CEMS) or as a manual stack sampling/monitoring device.
Robinson outlined some of the key aspects that should be taken into account in the use of FTIR. For example, FTIR produces a response that is corrected with software to remove background effects from materials such as moisture and carbon dioxide. Furthermore, instrument response is analysed by the software and compared with stored (traceable) spectral data. Consequently, any possible errors are less obvious than would be the case with more traditional techniques.
Further issues to be considered are the avoidance of condensation within the FTIR cell, spectroscopic interferences and the need to avoid losses in the sample line.
Two Standards exist relating to the use of FTIR in emissions monitoring – US EPA Method 320 and ASTM D6348. Robinson explained that the ASTM method is the most commonly used in the UK, but that it has its limitations. This is because it provides choices that that can lead to different results. Nevertheless, most people are using FTIR as an alternative to Standard Reference Methods or as a tool to investigate complex emissions at multiple sites.
NPL is involved with the UK’s STA (Source Testing Association) interest group for FTIR that is seeking to develop a new Method based on the ASTM. The group is also looking at ways to simplify the certification of new parameters on an already certified instrument.
Robinson explained that as a multi-gas analyser with a single sensor, calibration is relatively easy. In contrast, the following presentation given by Marc Coleman, also of NPL, outlined some of the potential advantages of Mass Spectrometry but conceded that multicomponent calibration is necessary and that this can take several days. In addition, the technology is currently not well suited to transportation between sites.
Another popular paper at the Conference was titled ‘MCERTS manual stack emission monitoring - the next 5 years’ presented by John Tipping, who manages MCERTS on behalf of the Environment Agency.
Tipping said that the scheme has come a long way since its inception five years ago. MCERTS is now being used extensively, not just for sites the Environment Agency regulates. It also provides the means with which to implement the new quality assurance standard EN14181 and monitoring strategy standard EN 15259 in the UK. There are currently about 400 individuals and 32 organisations with MCERTS; it has been a great success but continues to evolve.
However, feedback from customers over the last few months coupled with the results of unannounced visits has highlighted a number of areas that have failed to meet the MCERTS requirements and would benefit from further improvement. For example, contract review, in some cases, has not been as comprehensive as it should.
A number of changes have been made to the personnel competency standard that will both simplify and underpin the value of this element.
During a question and answer session, Tipping said that the stack testing market is, in some ways, too competitive. This is because a high level of competition is forcing down prices and thereby encouraging practitioners to cut costs at the expense of quality. He hoped that an increased level of policing would help to ensure that a quality service is provided at a fair price.
MCERTS conference, exhibition and workshops events were originally created to provide a forum for the exchange of information relating to the Environment Agency’s monitoring certification scheme. However, the events have grown to cover anyone involved with air quality, including process operators (Part A and B), regulators, local authorities, instrument manufacturers, test houses, contractors, consultants, researchers and academics. The next event will be staged in 2009.
