The European Industrial Emissions Directive maps out stricter limits for allowable emissions of sulfur dioxide from large industrial plants. Evidence emerged that the standard reference test method may not be capable of reliably proving compliance at targeted lower concentration levels. Faster, less labour-intensive instruments showed potential as a basis of a more sensitive method but could not be adopted as a standard method without necessary quality procedures.

The project Metrology for sampling and conditioning SO2 emissions from stacks clarified limitations of the existing SRM, proved the equivalence of instrumental methods, and led to the development of a new method for measuring SO2 concentration. Appointed as lead author, the project coordinator led the drafting of a CEN technical specification based on the method devised in the project. Drafts were enhanced by contributions of partners and other expert members of the technical committee for standardisation of methods for air quality (CEN/TC 264/WG 16).

The resulting technical specification CEN/TS 17021, published in January 2017, describes how to sample and determine concentrations of gaseous SO2 emissions from stacks based on instrumental techniques. It is both applicable to periodic measurements and calibrating automated measuring systems permanently installed on stacks, for regulatory or other purposes. CEN recognised the ‘great value’ of the project and ‘pivotal contributions’ of consortium members to the specification, which it hoped would influence a future revision of EN 14791. The specification enables plant operators to benefit from real-time data, facilitates the development of portable instrument markets, and allows the emissions monitoring community to embrace a less labour-intensive approach.

https://www.euramet.org/casestudies/casestudiesdetails/news/fit-for-purpose-emissions-testing/