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ISO 17025 Calibration Verification of Spark Emission Spectrometers. Presented by Ken Suddaby Canalytical Instrumentation Services Inc. 1110 Heritage Road, Unit 7 Burlington, Ontario Canada L7L 4X9 Tel: 905 331 3386 Fax: 905 331 3388. Canalytical. Incorporated in 1997.
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ISO 17025 Calibration Verification of Spark Emission Spectrometers
Presented byKen SuddabyCanalytical Instrumentation Services Inc.1110 Heritage Road, Unit 7Burlington, OntarioCanadaL7L 4X9 Tel: 905 331 3386Fax: 905 331 3388
Canalytical • Incorporated in 1997. • Sales and service representative for several manufacturers whose products include Spark Emission, ICP and Mercury Analyzers. • Provider of 3rd party service on various spectrometer brands.
QS9000 • Calibration work for QS 9000 companies to be performed by: • the manufacturer’s direct representative. OR • Accredited to ISO/IEC Guide 25 or ISO/IEC 17025
TS16949 ISO/TS 16949 will require that all suppliers comply with ISO 17025 and that all independent test and calibration lab sub-contractors be accredited to the standard.
Challenges to Accreditation • No Defined Standard to Certify compliance of Spark Emission performance. • ASTM only have recommended methods and practices. ie ASTM- E1009-95 Standard practice for Evaluating an Optical Emission Vacuum Spectrometer to Analyze Carbon and Low-Alloy Steel • Manufactures are not consistent with acceptance criteria.
Requirements for ISO17025 • Development of Quality Manual • Acceptance criteria of Spark emission spectrometers?
Criteria of Acceptance Precision Accuracy Test Uncertainty Ratio of 4:1 as Compared to Factory Specifications
Measurement Uncertainty • Type B Evaluation of Standard Uncertainty • As per NIST Technical Note 1297
Precision • CRM is Analyzed for 5 consecutive burns to obtain the Standard Deviation • Compared to the Instrument Manufacturers’ published precision data at the various levels of concentration.
Determination of Accuracy • Calculate the Standard Error (SE) from the Delta of the CRMs. Compare this data to • The Calculated Standard Error (SE) of the CRMs from their Confidence level.
The Report Includes
Customer receives a snapshot of each calibration curve’s integrity
Cover Letter • Includes: • Definitions • Exceptions, trends with recommended plans of action • Formulas
Definitions • Standard Error (SE) or Standard Error of Estimate (SEE) • This is a measure of how well a calibration has been defined; Standard Error (SE) is used in this practice as an indicator of accuracy. It is CRM (Certified Reference Material) dependant and instrument operator dependant. ATSM E 1009 • Precision (Repeatability) • The agreement among repeated measurements, usually expressed as repeatability or reproducibility. The precision is the Relative Standard Deviation (1 sigma). • Range • The analytical range of the calibration curve(s) of the particular element in the alloy tested. Represented in percent unless otherwise stated. • Content • The content of the sample, in percent, at which the comparison for precision was taken. • Alpha • The slope of the comparison between the analysis mean of the element and the Certified Value. • Delta • The difference between the actual certified value and the measured content. • Y-U • The measured content less the sum of the standard uncertainty and instrument confidence (U). • Y+U • The measured content plus the sum of the standard uncertainty and instrument confidence (U).
Certificate Requirements • Name, Address, Instrument, SN. • Elements, Exceptions, Standards. • Environmental Conditions • Uncertainty of Measurement • Evidence of Traceability
Customer Summary • A quick visual of each analytical line. • Provides the statistical data for each analytical line. • Includes: Standard Deviation of each CRM, Variance, 95% Confidence level, Measurement Uncertainty, Standard Error of the range tested. • Also provide the R2 Value and alpha. • ISO 17025 Certification
Identified trends Improved customers accuracy Identified hardware issues through precision