ASTM_E_2623_-_14.pdf

Designation:E262314Standard Practice forReporting Thermometer Calibrations1This standard is issued under the fixed designation E2623;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice contains reporting requirements for ther-mometer calibrations included in ASTM Committee E20 TestMethods.1.2 This practice covers reports of calibration for radiationthermometers,liquid-in-glassthermometers,resistancethermometers,digital thermometers,and new thermocouples.NOTE1This practice does not apply to used thermocouples.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E77 Test Method for Inspection and Verification of Ther-mometersE344 Terminology Relating to Thermometry and Hydrom-etryE1137 Specification for Industrial Platinum Resistance Ther-mometers2.2 Other Standards or Guides:ANSI/NCSL Z540.3-2006 American National Standard forCalibrationCalibration Laboratories and Measuring andTest EquipmentGeneral Requirements3ISO/IEC 17025:2005 General Requirements for the Compe-tence of Testing and Calibration Laboratories3JCGM100:2008 Evaluation of Measurement DataGuideto the Expression of Uncertainty in MeasurementISO/IEC Guide 98-3 Uncertainty of MeasurementPart 3:Guide to the Expression of Uncertainty in Measurement(GUM:1995)NIST Technical Note 1297 Guidelines for Evaluating andExpressing the Uncertainty of NIST MeasurementResults,1994 EditionUKAS M3003 The Expression of Uncertainty and Confi-dence in Measurement,Edition 2ANSI/NCSL Z540.2-1997(R2002)U.S.Guide to the Ex-pression of Uncertainty in Measurement3.Terminology3.1 DefinitionsDefinitions given in Terminology E344,unless otherwise defined herein,apply to terms as used in thispractice.3.2 Definitions of Terms Specific to This Standard:3.2.1 correction,nnumerical value added to the uncor-rected result of a measurement to compensate for errors.3.2.1.1 DiscussionThe correction is equal to the negativeof the estimated errors.Since the systematic error cannot beknown perfectly,the compensation cannot be complete.3.2.2 error,nthe indication of a thermometer or tempera-ture measuring device minus the true value of the correspond-ing input quantity.3.2.2.1 DiscussionSince the true value cannot bedetermined,in practice a conventional true value is used.Thisconcept applies mainly when the instrument is compared to areference standard.3.2.3 gradient zone,nthe section of a thermocouple that isexposed during a measurement to temperatures in the rangefrom tamb+0.1(tm tamb)to tamb+0.9(tm tamb),where tambisambient temperature and tmis the temperature of the measuringjunction(all in C).3.2.3.1 DiscussionThis term is used in thermocouple cali-bration reports as part of the description of the thermal profilealong the length of the thermocouple.Although thermocoupleemf is a function of the measuring and reference junctiontemperatures,the emf is actually generated along the length ofthe thermocouple,wherever the thermoelements pass through atemperature gradient.The gradient zone definition is intendedto describe,in an approximate way,the section of thermo-couple that created most of the emf during the calibration.3.2.4 half-maximum heated length,nthe distance betweenthe tip of the temperature sensor and the position along the1This practice is under the jurisdiction ofASTM Committee E20 on TemperatureMeasurement and is the direct responsibility of Subcommittee E20.07 on Funda-mentals in Thermometry.Current edition approved Dec.15,2014.Published January 2015.Originallyapproved in 2008.Last previous edition approved in 2008 as E2623 081.DOI:10.1520/E2623-14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 length of the sensor leads or sheath where the temperatureequals the average of the calibration-point and ambient tem-peratures.3.2.4.1 DiscussionThis term is used in thermocouple cali-bration reports as part of the description of the thermal profilealong the length of the thermocouple.4.Summary of Practice4.1 This practice describes the required information neces-sary for reporting results of temperature calibrations includedin ASTM Test Methods.5.