The 13^th meeting of the Working Group (WG) 41 of the Technical Committee (TC) 264 on air quality of the European Standard Committee (CEN) dealing with Instrumental Odour Monitoring Systems (IOMS) coded as CEN/TC 264/WG 41, took place in Bilbao, Spain the 3^rd and 4^th of July. A total of 16 experts met to discuss the new standard on IOMSs, previously known as e-noses.

A new Task Group 5 (TG5) was created in the previous meeting in Milan in order to deal with the implications of the standards on Automatic Measuring Systems (AMS) EN 141881 and EN 15267, on IOMSs. Among the many issues addressed in this meeting in Bilbao, a new proposal to bring a Quality Assurance Level (QAL) 1 was discussed.

    Some other important aspects were discussed during this meeting. One interesting topic was brought out to try to answer the following question: How many measurements are needed to define a claim like: 'IOMS features (x±σ) % of correct classifications'? The implications of this statement are important to IOMSs makers that pretend to prove that their system complies with the performance criteria set in this standard.

   EN14181 has now been in operation for over 15 years and describes the quality assurance procedures needed to assure that an IOMS installed to measure emissions to air is capable of meeting the uncertainty requirements on measured values given by legislation; e.g. EU Directives and BREF documents.

   Three different Quality Assurance Levels (QAL 1, QAL 2, and QAL 3) are described in the EN 14181 to cover the suitability of an IOMS for its measuring task before or during the purchase period of the IOMS (QAL 1), the validation of the AMS following its installation (QAL 2), and the control of the IOMS during its ongoing operation on an industrial plant (QAL 3). TG5 will try to adapt the text written right now to the specifics of the EN 14181 and 15267 to ensure the proper quality checks are made.

  The following picture shows the implications of the QAL during the purchase, installation and maintainance of an IOMS.

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