IAS CALIBRATION and TESTING LABORATORY
ACCREDITATION PROGRAMSDEFINITIONSRevised February 15, 2022
DEFINITIONSACCREDITATION:
Third-party attestation related to a conformity assessment body, conveying formal demonstrationof its competence, impartiality and consistent operation in performing specific conformity
assessment activities. (ISO/IEC 17000:2020)
ACCREDITATION BODY: Authoritative body that performs accreditation (ISO/IEC 17000:2020)
ACCREDITATION CRITERIA: Set of requirements used by an accrediting body which alaboratory must meet in order to be accredited. (ASQ The Measurement Quality Division (2012)
The Metrology Handbook, Second Edition, (Jay L. Bucher Ed.), ASQ Quality Press)
APAC: Asia Pacific Accreditation Cooperation.
ASSESSMENT: Process undertaken by an accreditation body to determine the competence ofa conformity assessment body, based on standard(s) and/or other normative documents and fora defined scope of accreditation (ISO/IEC 17011:2017)
AUTHORIZED REPRESENTATIVE: Individual who is authorized by the laboratory or parent
organization to sign the accreditation application and commit the laboratory to fulfill theaccreditation criteria. (Based on ISO/IEC 17011:2017)
BIPM: International Bureau of Weights and Measures
BASE QUANTITY: Quantity in a conventionally chosen subset of a given system of quantities,
where no subset quantity can be expressed in terms of the others. (JCGM 200:2012)
CALIBRATION: Operation that, under specified conditions, in a first step, establishes a relation
between the quantity values with measurement uncertainties provided by measurement
standards and corresponding indications with associated measurement uncertainties and, in aIAS/TL-CL/013
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from an indication. (JCGM 200:2012)
CALIBRATION ACTIVITY OR PROVIDER: A laboratory or facility—including personnel—thatperform calibrations in an established location or at customer location(s). It may be external orinternal, including subsidiary operations of a larger entity. It may be called a calibrationlaboratory, shop, or department; a metrology laboratory or department; or an industry-speciﬁcname; or any combination or variation of these.
(ASQ The Measurement Quality Division (2012) The Metrology Handbook, Second Edition, (JayL. Bucher Ed.), ASQ Quality Press)
CALIBRATION AND MEASUREMENT CAPABILITY (CMC): A CMC is a calibration andmeasurement capability available to customers under normal conditions: (a) as published in theBIPM key comparison database (KCDB) of the CIPM MRA; or (b) as described in the laboratory’s
scope of accreditation granted by a signatory to the ILAC Arrangement. (ILAC-P14:09/2020)
CALIBRATION PROGRAM: The set of interrelated or interacting elements necessary tomaintain the measurement performance of measuring and test equipment to definedrequirements. (ANSI/NCSL Z540.3-2006 (R2013))
CALIBRATION SEAL: A calibration seal is a device, placard, or label that, when removed ortampered with, and by virtue of its design and material, clearly indicates tampering. The purposeof a calibration seal is to ensure the integrity of the calibration. A calibration seal is usually
imprinted with a legend similar to “Calibration Void if Broken or Removed” or “Calibration Seal—
Do Not Break or Remove.” A calibration seal provides a means of deterring the user fromtampering with any adjustment point that can affect the calibration of an instrument and detecting
an attempt to access controls that can affect the calibration of an instrument. Note: A calibration
seal may also be referred to as a tamper seal. (ASQ The Measurement Quality Division (2012)
The Metrology Handbook, Second Edition, (Jay L. Bucher Ed.), ASQ Quality Press)
CAR (Corrective Action Request): IAS assessment finding that describes the failure to address,
or failure to implement a mandatory requirement of the relevant standard, international
requirement or IAS accreditation criteria. (IAS/ADM/052 IAS Guidance on Classification ofFindings)
CERTIFIED REFERENCE MATERIAL (CRM): Reference material accompanied bydocumentation issued by an authoritative body and providing one or more specified property
values with associated uncertainties and traceabilities, using valid procedures. (JCGM200:2012)
CERTIFICATE OF ACCREDITATION: Document issued by IAS to a laboratory that has met theconditions and criteria for accreditation. A current Certificate of Accreditation, accompanied bya Scope of Accreditation, may be used as proof of accredited status.
CGPM: General Conference on Weights and Measures
CIPM: International Committee for Weights and Measures

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COMBINED STANDARD MEASUREMENT UNCERTAINTY: Standard measurement
uncertainty that is obtained using the individual standard measurement uncertainties associatedwith the input quantities in a measurement model. (JCGM 200:2012)
COMPETENCE: For a laboratory, the demonstrated ability to perform the tests or calibrations
within the accreditation scope and to meet other criteria established by the accreditation body.
For a person, the demonstrated ability to apply knowledge and skills. Note: The word
qualiﬁcation is sometimes used in the personal sense, since it is a synonym and has more
accepted usage in the United States. (ASQ The Measurement Quality Division (2012) TheMetrology Handbook, Second Edition, (Jay L. Bucher Ed.), ASQ Quality Press)
CONCERN: Minor nonconformity with the requirements of the relevant standard, international
requirement or IAS accreditation criteria (IAS/ADM/052)
CONFORMITY ASSESSMENT BODY: Body that performs conformity assessment activities,
excluding accreditation. (ISO/IEC 17000:2020)
COVERAGE FACTOR: Number larger than one by which a combined standard measurement
uncertainty is multiplied to obtain an expanded measurement uncertainty. (JCGM 200:2012)
COVERAGE INTERVAL: Interval containing the set of true quantity values of a measurand witha stated probability, based on the information available (JCGM 200:2012)
COVERAGE PROBABILITY: Probability that the set of true quantity values of a measurand iscontained within a specified coverage interval. (JCGM 200:2012)
DECISION RULE: rule that describes how measurement uncertainty is accounted for when
stating conformity with a specified requirement. (ISO/IEC 17025:2017)
DERIVED QUANTITY: Quantity, in a system of quantities, defined in terms of the base quantitiesof that system. (JCGM 200:2012)
EXPANDED MEASUREMENT UNCERTAINTY: Product of a combined standard measurement
uncertainty and a factor larger than the number one. (JCGM 200:2012)FLEXIBLE SCOPE OF ACCREDITATION: Scope of accreditation expressed to allow
laboratories to make changes in methodology and other parameters which fall within thecompetence of the laboratory as confirmed by the accreditation body (based on ISO/IEC
17011:2017)
IAF: International Accreditation Forum. The world association of Conformity AssessmentAccreditation Bodies and other bodies interested in conformity assessment in the fields ofmanagement systems, products, services, personnel and other similar programmes ofconformity assessment. (https://www.iaf.nu)
ILAC: International Laboratory Accreditation Cooperation. The international organization for
accreditation bodies operating in accordance with ISO/IEC 17011 and involved in theaccreditation of conformity assessment bodies including calibration laboratories (using ISO/IEC17025), testing laboratories (using ISO/IEC 17025), medical testing laboratories (using ISOIAS/TL-CL/013
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(https://ilac.org/about-ilac/)
IMPARTIALITY: Presence of objectivity. (ISO/IEC 17025:2017)
INTERLABORATORY COMPARISON (ILC): Organization, performance, and evaluation oftests or calibrations on the same or similar items or materials by two or more laboratories inaccordance with predetermined conditions. (ISO/IEC 17025:2017)
INTERNAL AUDIT: systematic, independent and documented process conducted by, or on
behalf of the organization itself, for obtaining objective evidence and evaluating it objectively todetermine the extent to which the audit criteria are fulfilled. (ISO 19011:2018)
INTERNATIONAL STANDARD: (Standard that is adopted by an international
standardizing/standards organization and made available to the public. (ISO/IEC Guide 2:2004)
INTERNATIONAL SYSTEM OF QUANTITIES (ISQ): System of quantities based on the sevenbase quantities: length, mass, time, electric current, thermodynamic temperature, amount ofsubstance, and luminous intensity. (JCGM 200:2012)
INTERNATIONAL SYSTEM OF UNITS (SI): System of units, based on the International Systemof Quantities, their names and symbols, including a series of prefixes and their names andsymbols, together with rules for their use, adopted by the General Conference of Weights andMeasures (CGPM). (JCGM 200:2012)
INTRALABORATORY COMPARISON:
organization, performance and evaluation ofmeasurements or tests on the same or similar items within the same laboratory in accordancewith predetermined conditions. (ISO/IEC 17025:2017) LABORATORY: Body that performs one
or more of the following activities:- testing;- calibration;- sampling, associated with subsequent testing or calibration.
(ISO/IEC 17025:2017)
LEVEL OF CONFIDENCE: alternate expression used by the GUM for “coverage probability”.
MANAGEMENT REVIEW: Review by laboratory management of its management system atplanned intervals, in order to ensure its continuing suitability, adequacy and effectiveness,
including the stated policies and objectives related to the fulfilment of the ISO/IEC 17025
standard. (based on ISO/IEC 17025:2017)
MANAGEMENT SYSTEM: The way in which an organization manages the interrelated parts ofits business in order to achieve its objectives. (https://www.iso.org/management-systemstandards.html)
MEASURAND: Quantity intended to be measured (JCGM 200:2012)

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MEASUREMENT: Process of experimentally obtaining one or more quantity values that canreasonably be attributed to a quantity (JCGM 200:2012)
MEASUREMENT ACCURACY: Closeness of agreement between a measured quantity value
and a true quantity value of a measurand. (JCGM 200:2012)
MEASUREMENT ERROR: Measured quantity value minus a reference quantity value. (JCGM200:2012)
MEASUREMENT PRECISION: closeness of agreement between indications or measured
quantity values obtained by replicate measurements on the same or similar objects under
specified conditions. (JCGM 200:2012)
MEASUREMENT PROCEDURE: Detailed description of a measurement according to one ormore measurement principles and to a given measurement method, based on a measurement
model and including any calculation to obtain a measurement result. (JCGM 200:2012)
MEASUREMENT UNCERTAINTY Non-negative parameter characterizing the dispersion of thequantity values being attributed to a measurand, based on the information used. (JCGM200:2012)
MEASURING INSTRUMENT: Device used for making measurements, alone or in conjunction
with supplementary devices. (JCGM 200:2012)
METROLOGY: Science of measurement and its application. (JCGM 200:2012)
METROLOGICAL TRACEABILITY): Property of a measurement result whereby the result canbe related to a reference through a documented unbroken chain of calibrations, eachcontributing to the measurement uncertainty. (JCGM 200:2012)
METROLOGICAL TRACEABILITY CHAIN: Sequence of measurement standards andcalibrations that is used to relate a measurement result to a reference. (JCGM 200:2012)
MOBILE OPERATIONS: Operations that are independent of an established calibrationlaboratory facility. Mobile operations may work from an office space, home, vehicle, or use avirtual office.
MRA: Mutual Recognition Arrangement. For example, through the ILAC MRA, ILAC aims todemonstrate the equivalence of the operation of its Member Accreditation Bodies. As aconsequence, the competence (within the accredited scopes) of laboratories, inspection bodies,
proficiency testing providers and reference material producers accredited by these accreditation
bodies is demonstrated and recognized by all signatory accreditation bodies. (based on ILACP4:05/2019)
NATIONAL METROLOGY INSTITUTE (NMI): There is only one NMI in each country, and it
maintains that country’s national standards and provides traceability to the International Systemof Units (the SI) at stated levels of confidence – often called measurement uncertainty(https://www.npl.co.uk/resources/q-a/what-is-a-national-metrology-institute)
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Page 5 of 8NATURAL CONSTANT: A natural (physical) constant is a fundamental value that is acceptedby the scientiﬁc community as valid. Natural constants are used in the basic theoreticaldescriptions of the universe. Examples of natural physical constants important in metrology are
the speed of light in a vacuum (c), the triple point of water (273.16 K), the quantum charge ratio(h/e), the gravitational constant (G), the ratio of a circle’s circumference to its diameter (p), andthe base of natural logarithms (e). (ASQ The Measurement Quality Division (2012) TheMetrology Handbook, Second Edition, (Jay L. Bucher Ed.), ASQ Quality Press)
NONCONFORMITY: non-fulfilment of a requirement (ISO/IEC 17021-1:2015)
OFF-SITE TESTING/CALIBRATION: Any testing or calibration conducted at a facility that isdifferent than the permanent facility assessed and accredited by IAS. (IAS/TL-CL/026)
PROFICIENCY TESTING (PT): Evaluation of participant performance against pre-establishedciriteria by means of interlaboratory comparisons. (ISO/IEC 17025:2017)
QUANTITY VALUE: Number and reference together expressing magnitude of a quantity (JCGM200:2012)
RANDOM MEASUREMENT ERROR: Component of measurement error that in replicate
measurements varies in an unpredictable manner. (JCGM 200:2012)
REFERENCE MATERIAL: Material, sufficiently homogeneous and stable with reference tospecified properties, which has been established to be fit for its intended use in measurement
or in examination of nominal properties. (JCGM 200:2012).
REFERENCE MEASUREMENT STANDARD: Measurement standard designated for thecalibration of other measurement standards for quantities of a given kind in a given organization
or at a given location. (JCGM 200:2012)
RISK: Effect of uncertainty on objectives (ISO 31000:2018)
REQUIREMENT: Provision that conveys criteria to be fulfilled.
SCOPE OF ACCREDITATION: Specific laboratory activities for which accreditation is sought or
has been granted (based on ISO/IEC 17011:2017)
STANDARD, PRIMARY: Measurement standard established using a primary reference
measurement procedure, or created as an artifact, chosen by convention. ((JCGM 200:2012)
STANDARD, SECONDARY: Measurement standard established through calibration withrespect to a primary measurement standard for a quantity of the same kind. (JCGM 200:2012)
STANDARD, WORKING: Measurement standard that is used routinely to calibrate or verify
measuring instruments or measuring systems. (JCGM 200:2012)
STANDARD MEASUREMENT UNCERTAINTY: Measurement uncertainty expressed as astandard deviation. (JCGM 200:2012)
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STATEMENT OF UNCERTAINTY: Statement on the calibration certificate or test report of thevalue of measurement uncertainty for any specific test or calibration.
SYSTEM OF QUANTITES: Set of quantities together with a set of noncontradictory equations
relating those quantities. (JCGM 200:2012)
SYSTEMATIC MEASUREMENT ERROR: Component of measurement error that in replicate
measurements remains constant or varies in a predictable manner. (JCGM 200:2012)TEST UNCERTAINTY RATIO: The ratio of the span of the tolerance of a measurement quantity
subject to calibration, to twice the 95% expanded uncertainty of the measurement process usedfor calibration. (ANSI/NCSL Z540.3-2006 (R2013)
TRACEABILITY: see Metrological Traceability definition
TYPE A EVALUATION OF MEASUREMENT UNCERTAINTY: Evaluation of a component ofmeasurement uncertainty by a statistical analysis of measured quantity values obtained under
defined measurement conditions. (JCGM 200:2012)
TYPE B EVALUATION OF MEASUREMENT UNCERTAINTY): Evaluation of a component ofmeasurement uncertainty determined by means other than a Type A evaluation of measurement
uncertainty. (JCGM 200:2012)UNCERTAINTY BUDGET: Statement of a measurement uncertainty, of the components of thatmeasurement uncertainty, and of their calculation and combination. (JCGM 200:2012)UNCERTAINTY OF MEASUREMENT: see measurement uncertainty
VALIDATION: Confirmation of plausibility for a specific intended use or application through theprovision of objective evidence that specified requirements have been fulfilled. (ISO/IEC17000:2020)
VERIFICATION: Confirmation of truthfulness through the provision of objective evidence thatspecified requirements have been fulfilled. (ISO/IEC 17000:2020)

REFERENCES
ANSI/NCSL Z540.3-2006(R2013) American National Standard for Calibration—Requirements
for the Calibration of Measuring and Test Equipment (withdrawn October 2020)
ASQ The Measurement Quality Division (2012) The Metrology Handbook, Second Edition, (JayL. Bucher Ed.), ASQ Quality Press
IAS/ADM/052 IAS Guidance on Classification of Findings
IAS/TL-CL/026 IAS Policy on Off-Site Testing/Calibration
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Page 7 of 8ILAC-P14:09/2020 ILAC Policy for Measurement Uncertainty in Calibration
ISO 19011:2018 Guidelines for auditing management systems
ISO 31000:2018 Risk Management - Guidelines
ISO/IEC Guide 2:2004 Standardization and Related Activities – General Vocabulary
ISO/IEC 17000:2020 Conformity assessment – Vocabulary and general principles
ISO/IEC 17011:2017 Conformity assessment – Requirements for accreditation bodies
accrediting conformity assessment bodies
ISO/IEC 17021-1:2015 Conformity assessment — Requirements for bodies providing audit andcertification of management systems
ISO/IEC 17025:2017General requirements for the competence of testing and calibrationlaboratories
JCGM 100:2008 Evaluation of Measurement Data – Guide to the expression of uncertainty inmeasurement (GUM)
JCGM 200:2012 International Vocabulary of metrology – Basic and general concepts andassociated terms (VIM)

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