Presentation on theme: "ISO 17025 Calibration Verification of Spark Emission Spectrometers."— Presentation transcript:
ISO Calibration Verification of Spark Emission Spectrometers
Presented by Ken Suddaby Canalytical Instrumentation Services Inc Heritage Road, Unit 7 Burlington, Ontario Canada L7L 4X9 Tel: Fax:
Canalytical Incorporated in Sales and service representative for several manufacturers whose products include Spark Emission, ICP and Mercury Analyzers. Provider of 3 rd party service on various spectrometer brands.
Why ISO 17025
Calibration work for QS 9000 companies to be performed by: –the manufacturers direct representative. OR –Accredited to ISO/IEC Guide 25 or ISO/IEC QS9000
TS16949 ISO/TS will require that all suppliers comply with ISO 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- E Standard practice for Evaluating an Optical Emission Vacuum Spectrometer to Analyze Carbon and Low-Alloy Steel Manufactures are not consistent with acceptance criteria.
Process to Accreditation
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
Sample Data Certified MeasuredStandardNumber ofCoverage95% StandardContent %UncertaintyContent %DeviationMeasurementsDeltaFactorConfidence YunKUY-UY+U BAS BAS BAS BAS CMSI BAS BAS
Customer receives a snapshot of each calibration curves integrity
Summary Sheet Precision 1 Sigma Standard Error of EstimatePrecisionSEE Range %Content %FactoryActualFactoryActualPass/Fail Al PASS C PASS Co PASS Cr PASSFAIL Cu PASS Mg PASS Mn PASS Mo PASS Ni PASS P PASS S PASS Si PASS Ti PASS V PASS
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 R 2 Value and alpha. ISO Certification