Abstract Title: | MEASUREMENT UNCERTAINTIES AND LIMIT OF DETECTION/LIMIT OF QUANTIFICATION - observations from Finnish intercomparison measurements |
Presenter Name: | Ms Tuula Pellikka |
Co-authors: | Mrs Tuula Kajolinna |
Company/Organisation: | VTT Technical Research Centre of Finland |
Country: | Finland |
Abstract Information :
VTT Technical Research Centre of Finland has organized intercomparisons measurements from 1980´s. These measurements have been organized using real stacks. This presentation will describe some challenges that emission measurement laboratories faced 30 years ago, compared to the challenges that they face today. The aim of these intercomparisons has been naturally to evaluate the performance of participating laboratories and to identify if some corrective actions are needed. However, in addition to this, these measurement campaigns have provided very important platform for the dissemination of the knowledge in Finland.
Previous national intercomparison measurements were organised in May 2019 at the waste to energy plant. During this campaign all pollutants which are required to be measured by Waste Incineration Directive were measured, NOx, SO2, CO, HCl, HF, TVOC, particles, heavy metals and PCDD/F, as well as temperature and flue gas velocity. Eight accredited stack testing teams took part in these measurements.
In this presentation examples are given about the results, with the emphasis on how stack testing teams calculate and report their measurement uncertainties and limit of detection (LOD) or limit of quantification (LOQ). At the moment in Europe there does not exist any standard procedure for these topics (for example should LOD or LOQ be used, how to calculate these values or should we use instead measurement uncertainties?). In addition, many standards (such as EN 13211, EN 14385 and EN 1911) are lacking information about how to calculate measurement uncertainties, what should be included in the uncertainty budget as well as what is the maximum permissible uncertainty when this method is used as standard reference method. There is a clear need to develop guidance in Europe in order to guarantee harmonized information about the emissions when we approach zero concentration levels.