ISO/IEC 17043:2010(E)ISO/IEC17043First edition2010-02-01Conformity assessment — Generalrequirements for proficiency testing

ISO/IEC 17043:2010(E)Contents PageForeword .ivIntroduction.v1 Scope.12 Normative references.13 Terms and definitions .14 Technical Requirements .44.1 General .44.2 Personnel .44.3 Equipment, accommodation and environment .54.4 Design of proficiency testing schemes.64.5 Choice of method or procedure.104.6 Operation of proficiency testing schemes.114.7 Data analysis and evaluation of proficiency testing scheme results .124.8 Reports .134.9 Communication with participants.144.10 Confidentiality.155 Management requirements.155.1 Organization.155.2 Management system .165.3 Document control.175.4 Review of requests, tenders and contracts.185.5 Subcontracting services.195.6 Purchasing services and supplies .195.7 Service to the customer.205.8 Complaints and appeals .205.9 Control of nonconforming work .205.10 Improvement .205.11 Corrective actions .215.12 Preventive actions.215.13 Control of records .225.14 Internal audits .225.15 Management reviews .23Annex A (informative) Types of proficiency testing schemes .24Annex B (informative) Statistical methods for proficiency testing.28Annex C (informative) Selection and use of proficiency testing.35Bibliography.39

ISO/IEC 17043:2010(E)ForewordISO (the International Organization for Standardization) and IEC (the International ElectrotechnicalCommission) form the specialized system for worldwide standardization. National bodies that are members ofISO or IEC participate in the development of International Standards through technical committeesestablished by the respective organization to deal with particular fields of technical activity. ISO and IECtechnical committees collaborate in fields of mutual interest. Other international organizations, governmentaland non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of conformityassessment, the ISO Committee on conformity assessment (CASCO) is responsible for the development ofInternational Standards and Guides.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.Draft International Standards are circulated to the national bodies for voting. Publication as an InternationalStandard requires approval by at least 75 % of the national bodies casting a vote.Attention is drawn to the possibility that some of the elements of this document may be the subject of patentrights. ISO shall not be held responsible for identifying any or all such patent rights.ISO/IEC 17043 was prepared by the ISO Committee on conformity assessment (CASCO).It was circulated for voting to the national bodies of both ISO and IEC, and was approved by bothorganizations.This first edition of ISO/IEC 17043 cancels and replaces ISO/IEC Guide 43-1:1997 andISO/IEC Guide 43-2:1997, which have been technically revised.

ISO/IEC 17043:2010(E)IntroductionInterlaboratory comparisons are widely used for a number of purposes and their use is increasinginternationally. Typical purposes for interlaboratory comparisons include:a) evaluation of the performance of laboratories for specific tests or measurements and monitoringlaboratories' continuing performance;b) identification of problems in laboratories and initiation of actions for improvement which, for example, maybe related to inadequate test or measurement procedures, effectiveness of staff training and supervision,or calibration of equipment;c) establishment of the effectiveness and comparability of test or measurement methods;d) provision of additional confidence to laboratory customers;e) identification of interlaboratory differences;f) education of participating laboratories based on the outcomes of such comparisons;g) validation of uncertainty claims;h) evaluation of the performance characteristics of a method – often described as collaborative trials;i) assignment of values to reference materials and assessment of their suitability for use in specific test ormeasurement procedures; andj) support for statements of the equivalence of measurements of National Metrology Institutes through “keycomparisons” and supplementary comparisons conducted on behalf of the International Bureau ofWeights and Measurement (BIPM) and associated regional metrology organizations.Proficiency testing involves the use of interlaboratory comparisons for the determination of laboratoryperformance, as listed in a) to g) above. Proficiency testing does not usually address h), i) and j) becauselaboratory competence is assumed in these applications, but these applications can be used to provideindependent demonstrations of laboratory competence. The requirements of this International Standard canbe applied to many of the technical planning and operational activities for h), i) and j).The need for ongoing confidence in laboratory performance is not only essential for laboratories and theircustomers but also for other interested parties, such as regulators, laboratory accreditation bodies and otherorganizations that specify requirements for laboratories. ISO/IEC 17011 requires accreditation bodies to takeaccount of laboratories' participation and performance in proficiency testing. There is a growing need forproficiency testing for other conformity assessment activities, such as inspection or product certification. Mostof the requirements in this International Standard apply to those evolving areas, especially regardingmanagement, planning and design, personnel, assuring quality, confidentiality, and other aspects, asappropriate.This International Standard has been prepared to provide a consistent basis for all interested parties todetermine the competence of organizations that provide proficiency testing. In doing so it replaces both partsof ISO/IEC Guide 43:1997. ISO/IEC Guide 43 included not only guidance on development and operation ofproficiency testing and selection and use of proficiency testing by laboratory accreditation bodies, but alsouseful descriptions of typical types of proficiency testing. This International Standard has preserved andupdated the principles for the operation of proficiency testing described in ISO/IEC Guide 43 and has retainedin Annexes A to C information on typical types of proficiency testing schemes, guidance on appropriatestatistical methods, selection and use of proficiency testing schemes by laboratories, accreditation bodies,regulatory bodies, and other interested parties.

ISO/IEC 17043:2010(E)Conformity assessment — General requirements for proficiencytesting1 ScopeThis International Standard specifies general requirements for the competence of providers of proficiencytesting schemes and for the development and operation of proficiency testing schemes. These requirementsare intended to be general for all types of proficiency testing schemes, and they can be used as a basis forspecific technical requirements for particular fields of application.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For datedreferences, only the edition cited applies. For undated references, the latest edition of the referenceddocument (including any amendments) applies.ISO/IEC 17000:2004, Conformity assessment — Vocabulary and general principlesISO/IEC Guide 99:2007, International vocabulary of metrology — Basic and general concepts and associatedterms (VIM)3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO/IEC 17000:2004,ISO/IEC Guide 99:2007 and the following apply.3.1assigned valuevalue attributed to a particular property of a proficiency test item3.2coordinatorone or more individuals with responsibility for organizing and managing all of the activities involved in theoperation of a proficiency testing scheme3.3customerorganization or individual for which a proficiency testing scheme is provided through a contractualarrangement3.4interlaboratory comparisonorganization, performance and evaluation of measurements or tests on the same or similar items by two ormore laboratories in accordance with predetermined conditions1 / 39

ISO/IEC 17043:2010(E)3.5outlierobservation in a set of data that appears to be inconsistent with the remainder of that setNOTE An outlier can originate from a different population or be the result of an incorrect recording or other grosserror.3.6participantlaboratory, organization or individual that receives proficiency test items and submits results for review by theproficiency testing providerNOTE In some cases, the participant can be an inspection body.3.7proficiency testingevaluation of participant performance against pre-established criteria by means of interlaboratory comparisonsNOTE 1 For the purposes of this International Standard, the term “proficiency testing” is taken in its widest sense andincludes, but is not limited to:a) quantitative scheme — where the objective is to quantify one or more measurands of the proficiency test item;b) qualitative scheme — where the objective is to identify or describe one or more characteristics of the proficiency testitem;c) sequential scheme — where one or more proficiency test items are distributed sequentially for testing ormeasurement and returned to the proficiency testing provider at intervals;d) simultaneous scheme — where proficiency test items are distributed for concurrent testing or measurement within adefined time period;e) single occasion exercise — where proficiency test items are provided on a single occasion;f) continuous scheme — where proficiency test items are provided at regular intervals;g) sampling — where samples are taken for subsequent analysis; andh) data transformation and interpretation — where sets of data or other information are furnished and the information isprocessed to provide an interpretation (or other outcome).NOTE 2 Some providers of proficiency testing in the medical area use the term “External Quality Assessment (EQA)”for their proficiency testing schemes, or for their broader programmes, or both (see Annex A). The requirements of thisInternational Standard cover only those EQA activities that meet the definition of proficiency testing.3.8proficiency test itemsample, product, artefact, reference material, piece of equipment, measurement standard, data set or otherinformation used for proficiency testing3.9proficiency testing providerorganization which takes responsibility for all tasks in the development and operation of a proficiency testingscheme3.10proficiency testing roundsingle complete sequence of distribution of proficiency test items, and the evaluation and reporting of resultsto the participants2 / 39

ISO/IEC 17043:2010(E)3.11proficiency testing schemeproficiency testing designed and operated in one or more rounds for a specified area of testing, measurement,calibration or inspectionNOTE A proficiency testing scheme might cover a particular type of test, calibration, inspection or a number of tests,calibrations or inspections on proficiency test items.3.12robust statistical methodstatistical method insensitive to small departures from underlying assumptions surrounding an underlyingprobabilistic model3.13standard deviation for proficiency assessmentmeasure of dispersion used in the evaluation of results of proficiency testing, based on the availableinformationNOTE 1 The standard deviation applies only to ratio and differential scale results.NOTE 2 Not all proficiency testing schemes evaluate proficiency based on the dispersion of results.3.14subcontractororganization or individual engaged by the proficiency testing provider to perform activities specified in thisInternational Standard and that affect the quality of a proficiency testing schemeNOTE The term “subcontractor” includes what many proficiency testing providers call collaborators.3.15metrological traceabilityproperty of a measurement result whereby the result can be related to a reference through a documentedunbroken chain of calibrations, each contributing to the measurement uncertaintyNOTE 1 For this definition, a “reference” can be a definition of a measurement unit through its practical realization, or ameasurement procedure including the measurement unit for a non-ordinal quantity, or a measurement standard.NOTE 2 Metrological traceability requires an established calibration hierarchy.NOTE 3 Specification of the reference must include the time at which this reference was used in establishing thecalibration hierarchy, along with any other relevant metrological information about the reference, such as when the firstcalibration in the calibration hierarchy was performed.NOTE 4 For measurements with more than one input quantity in the measurement model, each of the input quantityvalues should itself be metrologically traceable and the calibration hierarchy involved may form a branched structure or anetwork. The effort involved in establishing metrological traceability for each input quantity value should be commensuratewith its relative contribution to the measurement result.NOTE 5 Metrological traceability of a measurement result does not ensure that the measurement uncertainty isadequate for a given purpose or that there is an absence of mistakes.NOTE 6 A comparison between two measurement standards may be viewed as a calibration if the comparison is usedto check and, if necessary, correct the quantity value and measurement uncertainty attributed to one of the measurementstandards.NOTE 7 The ILAC1) considers the elements for confirming metrological traceability to be an unbroken metrologicaltraceability chain to an international measurement standard or a national measurement standard, a documentedmeasurement uncertainty, a documented measurement procedure, accredited technical competence, metrologicaltraceability to the SI, and calibration intervals (see ILAC P-10:2002).1) International Laboratory Accreditation Cooperation.3 / 39

ISO/IEC 17043:2010(E)NOTE 8 The abbreviated term “traceability” is sometimes used to mean “metrological traceability” as well as otherconcepts, such as “sample traceability” or “document traceability” or “instrument traceability” or “material traceability”,where the history (“trace”) of an item is meant. Therefore, the full term of “metrological traceability” is preferred if there isany risk of confusion.[ISO/IEC Guide 99:2007, definition 2.41]3.16measurement uncertaintyuncertainty of measurementuncertaintynon-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand,based on the information usedNOTE 1 Measurement uncertainty includes components arising from systematic effects, such as componentsassociated with corrections and the assigned quantity values of measurement standards, as well as the definitionaluncertainty. Sometimes estimated systematic effects are not corrected for but, instead, associated measurementuncertainty components are incorporated.NOTE 2 The parameter may be, for example, a standard deviation called standard measurement uncertainty (or aspecified multiple of it), or the half-width of an interval, having a stated coverage probability.NOTE 3 Measurement uncertainty comprises, in general, many components. Some of these may be evaluated byType A evaluation of measurement uncertainty from the statistical distribution of the quantity values from series ofmeasurements and can be characterized by standard deviations. The other components, which may be evaluated byType B evaluation of measurement uncertainty, can also be characterized by standard deviations, evaluated fromprobability density functions based on experience or other information.NOTE 4 In general, for a given set of information, it is understood that the measurement uncertainty is associated witha stated quantity value attributed to the measurand. A modification of this value results in a modification of the associateduncertainty.[ISO/IEC Guide 99:2007, definition 2.26]4 Technical Requirements4.1 GeneralThe development and operation of proficiency testing schemes shall be undertaken by proficiency testingproviders having competence to conduct interlaboratory comparisons and access to expertise with theparticular type of proficiency test items. Proficiency testing providers or their subcontractors shall also havecompetence in the measurement of the properties being determined.NOTE ISO/IEC 17025 or ISO 15189 can be used to demonstrate the competence of a proficiency testing provider'slaboratory, or the laboratory subcontracted to perform tests or measurements related to the proficiency testing schemes.ISO Guide 34 can be used to demonstrate the competence of producers of reference materials that provide proficiencytest items.4.2 Personnel4.2.1 The proficiency testing provider shall have managerial and technical personnel with the necessaryauthority, resources and technical competence required to perform their duties.4.2.2 The proficiency testing provider's management shall define the minimum levels of qualification andexperience necessary for the key positions within its organization and ensure those qualifications are met.4.2.3 The proficiency testing provider shall use personnel who are either employed by, or under contract toit. Where contracted and additional technical and key support personnel are used, the proficiency testingprovider shall ensure that such personnel are supervised and competent and that they work in accordancewith the management system.4 / 39

ISO/IEC 17043:2010(E)NOTE Where technical experts are used on an ad-hoc basis or as part of an advisory or steering group (see,the existence of formal agreements through, for example, group terms of reference or other means, can be considered tosatisfy this requirement.4.2.4 The proficiency testing provider shall authorize specific personnel to:a) select appropriate proficiency test items;b) plan proficiency testing schemes;c) perform particular types of sampling;d) operate specific equipment;e) conduct measurements to determine stability and homogeneity, as well as assigned values andassociated uncertainties of the measurands of the proficiency test item;f) prepare, handle and distribute proficiency test items;g) operate the data processing system;h) conduct statistical analysis;i) evaluate the performance of proficiency testing participants;j) give opinions and interpretations; andk) authorize the issue of proficiency testing reports.4.2.5 The proficiency testing provider shall maintain up-to-date records of the relevant authorization(s),competence, educational and professional qualifications, training, skills and experience of all technicalpersonnel, including contracted personnel. This information shall be readily available and shall include thedate on which competence to perform their assigned tasks was assessed and confirmed.4.2.6 The proficiency testing provider shall formulate the objectives with respect to the education, training,and skills for each staff member involved with the operation of the proficiency testing scheme. The proficiencytesting provider shall have a policy and procedures for identifying training needs and providing training ofpersonnel. The training programme shall be relevant to the present and anticipated needs of the proficiencytesting provider.NOTE It is advisable to consider the need to retrain staff periodically. Staff training policies can take account oftechnological change, the need to demonstrate ongoing competence and aim at continual skills upgrading.4.2.7 The proficiency testing provider shall ensure that staff receive the necessary training to ensurecompetent performance of measurements, operation of equipment and any other activities which affect thequality of the proficiency testing scheme. The effectiveness of training activities shall be evaluated.NOTE Objective measures can be used to assess the attainment of competence.4.3 Equipment, accommodation and environment4.3.1 The proficiency testing provider shall ens

ISO/IEC 17043 was prepared by the ISO Committee on conformity assessment (CASCO). It was circulated for voting to the national bodies of both ISO and IEC, and was approved by both organizations. This first edition of ISO/IEC 17043 cancels and replaces ISO/IEC Guide 43-1:1997 and ISO/IEC Guide