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Quality assurance of automated measurement systems. EN14181 approach General Quality Assurance Level 1 (QAL 1) Quality Assurance Level 2 (QAL 2) Quality Assurance Level 3 (QAL 3) Annual Surveillance Test (AST). Contents of this presentation. Incited by (European) environmental legislation
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EN14181 approach General Quality Assurance Level 1 (QAL 1) Quality Assurance Level 2 (QAL 2) Quality Assurance Level 3 (QAL 3) Annual Surveillance Test (AST) Contents of this presentation
Incited by (European) environmental legislation Quality assurance of Automated Measurement Systems (AMS) without specification of measurement principle Netherlands: Continuous and Predictive emission monitoring systems (CEMS and PEMS) Required uncertainty specified in legislation/permit Expressed as 95% confidence interval Confidence interval expressed as % of emission limit value EN 14181 approach: general (1)
EN 14181 approach: general (2) • four Quality Assurance Levels (QAL) • QAL1-3 • Annual Surveillance Test (AST)
EN 14181 approach: QAL1 • Once only; during selection of measurement system • Identification of all uncertainty sources • Quantification of each uncertainty source • Specification of equipment • Actual circumstances • Calculation of the total uncertainty • Compliance test for uncertainty and response time • Calculation of statistical data for QAL3
EN 14181 approach: QAL2 (1) • After installation and every 3/5 years • Calibration • Accredited laboratory • At least15 parallel measurements with Standard Reference Method (SRM) in 3 days within 4 weeks • Sampling system included • Calculation of calibration line (y=a+bx) • Implementation of calibration line • Determination of the valid calibration range
EN 14181 approach: QAL2 (2) • Test for variability • compliance test for uncertainty • Functionality tests (see AST)
EN 14181 approach: QAL3 • Periodic test for on going quality controlby operator • Zero and span check with control gasses • Evaluation of responses with Cusum/Shewart cards • Action when limits (QAL1) are exceeded • Adjustment of settings of analyser • Maintenance • Check on operation of AMS within valid calibration range • Less than 40% of measurements outside valid range • 5 weeks: less than 5% of measurements in a week outside valid range
EN 14181 approach: AST (1) • Yearly verification test • Functionality test • Inspection of sampling system for leakages and contamination • Inspection on alignment of in-situ measurements • Check on responstime and linearity • Check on documentation (log books, maintenance an functionality reports) • Serviceability
EN 14181 approach: AST (2) • Verification measurements • Accredited laboratory • 5 parallel measurements with Standard Reference Method (SRM) in 1 day • Check on validity of calibration line
EN 14181 approach • four Quality Assurance Levels (QAL) • QAL1-3 • Annual Surveillance Test (AST)