Setting up a decision rule from estimated uncertainty: emission limit value for PCDD and PCDF incineration plants in Wallonia, Belgium

• Published in: Accreditation and quality assurance Vol. 13; no. 11; pp. 639 - 644
• Main Authors: Bergmans, B., Idczak, F., Maetz, P., Nicolas, J., Petitjean, S.
• Format: Journal Article Conference Proceeding Web Resource
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-11-2008; Springer; Springer Nature B.V
• Subjects: Analysis methods; Analytical Chemistry; Applied sciences; Biochemistry; Bottom-up; Chemistry; Chemistry and Materials Science; Chromatography; Combustion; Commercial Law; Compliance; Decision making; Dioxin; Ecotoxicology; Environmental sciences & ecology; Exact sciences and technology; Food Science; General Paper; Incineration; Legislation; Life sciences; Marketing; Mathematical analysis; Outdoor air quality; Ovens & stoves; Pollution; Sciences de l’environnement & écologie; Sciences du vivant; Top-down; Uncertainty; Waste disposal; Wastes; Belgium; Decision-making; Uncertainty; Top-down; Dioxin; Bottom-up; Stability; Overlap; Wastes; Sampling
• ISSN: 0949-1775; 1432-0517; 1432-0517
• DOI: 10.1007/s00769-008-0447-x

Complex analytical procedures are often required to prove the non-compliance with a specific legislation. In the case of a small overlap of the limit, integration of the method uncertainty in the decision-making process is essential. The decision rule proposed in Wallonia, Belgium, for the non-compliance of waste incineration plants with the EU limit value for PCDD and PCDF emissions is presented. The method uncertainty was estimated annually over 6 years from duplicate measurements using two top-down approaches. Depending on the congener, the standard uncertainty varies from 30 to 85%, with a good correlation between calculations. The analytical contribution was estimated using a bottom-up evaluation. The impact of the sampling step was deduced from the whole estimation and represents more than 80% of the total uncertainty budget. No optimisation is foreseen at this time because of practical field constraints. Based on the average fraction of each congener, the uncertainty associated with the measurement result has been established and shows a high stability over the years. Using this value, a guard band has been calculated and will be proposed to the regulatory body.