ASTM E2847-21

Standard Test Method for  Calibration and Accuracy Verification of Wideband Infrared Thermometers

SIGNIFICANCE AND USE
5.1 This test method provides guidelines and basic test methods for the accuracy verification of infrared thermometers. It includes test set-up and calculation of uncertainties. It is intended to provide the user with a consistent method, while remaining flexible in the choice of calibration equipment. It is understood that the uncertainty obtained depends in large part upon the apparatus and instrumentation used. Therefore, since this guide is not prescriptive in approach, it provides detailed instruction in uncertainty evaluation to accommodate the variety of apparatus and instrumentation that may be employed.  
5.2 This test method is intended primarily for calibrating handheld infrared thermometers. However, the techniques described in this guide may also be appropriate for calibrating other classes of radiation thermometers. It may also be of help to those calibrating thermal imagers.  
5.3 This test method specifies the necessary elements of the report of calibration for an infrared thermometer. The required elements are intended as a communication tool to help the end user of these instruments make accurate measurements. The elements also provide enough information, so that the results of the calibration can be reproduced in a separate laboratory.
SCOPE
1.1 This test method covers electronic instruments intended for measurement of temperature by detecting the intensity of thermal radiation exchanged between the subject of measurement and the sensor.  
1.2 The devices covered by this test method are referred to as infrared thermometers in this document.  
1.3 The infrared thermometers covered in this test method are instruments that are intended to measure temperatures below 1000°C, measure thermal radiation over a wide bandwidth in the infrared region, and are direct-reading in temperature.  
1.4 This test method covers best practice in calibrating infrared thermometers. It addresses concerns that will help the user perform more accurate calibrations. It also provides a structure for calculation of uncertainties and reporting of calibration results to include uncertainty.  
1.5 Details on the design and construction of infrared thermometers are not covered in this test method.  
1.6 This test method does not cover infrared thermometry above 1000°C. It does not address the use of narrowband infrared thermometers or infrared thermometers that do not indicate temperature directly.  
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2021
• ICS: 17.200.20 - Temperature-measuring instruments
• Technical Committee: E20 - Temperature Measurement
• Drafting Committee: E20.02 - Radiation Thermometry

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:E2847 −21
Standard Test Method for
Calibration and Accuracy Verification of Wideband Infrared
1
Thermometers
This standard is issued under the fixed designation E2847; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
1.1 This test method covers electronic instruments intended
mendations issued by the World Trade Organization Technical
for measurement of temperature by detecting the intensity of
Barriers to Trade (TBT) Committee.
thermal radiation exchanged between the subject of measure-
ment and the sensor.
2. Referenced Documents
1.2 The devices covered by this test method are referred to
2
2.1 ASTM Standards:
as infrared thermometers in this document.
E344 Terminology Relating to Thermometry and Hydrom-
1.3 The infrared thermometers covered in this test method
etry
are instruments that are intended to measure temperatures
E1256 Test Methods for Radiation Thermometers (Single
below 1000°C, measure thermal radiation over a wide band-
Waveband Type)
width in the infrared region, and are direct-reading in tempera-
E2758 Guide for Selection and Use of Wideband, Low
ture.
Temperature Infrared Thermometers
1.4 This test method covers best practice in calibrating
3. Terminology
infrared thermometers. It addresses concerns that will help the
3.1 Definitions of Terms Specific to This Standard:
user perform more accurate calibrations. It also provides a
3.1.1 cavity bottom, n—the portion of the cavity radiation
structure for calculation of uncertainties and reporting of
source forming the end of the cavity.
calibration results to include uncertainty.
3.1.1.1 Discussion—The cavity bottom is the primary area
1.5 Details on the design and construction of infrared
where an infrared thermometer being calibrated measures
thermometers are not covered in this test method.
radiation.
1.6 This test method does not cover infrared thermometry
3.1.2 cavity radiation source, n—a concave shaped geom-
above 1000°C. It does not address the use of narrowband
etry approximating a perfect blackbody of controlled tempera-
infrared thermometers or infrared thermometers that do not
ture and defined emissivity used for calibration of radiation
indicate temperature directly.
thermometers.
1.7 The values stated in SI units are to be regarded as the 3.1.2.1 Discussion—Acavity radiation source is a subset of
standard. The values given in parentheses are for information
thermal radiation sources.
only. 3.1.2.2 Discussion—To be a cavity radiation source of
practicalvalueforcalibration,atleast90 %ofthefield-of-view
1.8 This standard does not purport to address all of the
of a radiation thermometer is expected to be incident on the
safety concerns, if any, associated with its use. It is the
cavity bottom. In addition, the ratio of the length of the cavity
responsibility of the user of this standard to establish appro-
versus the cavity diameter is expected to be greater than or
priate safety, health, and environmental practices and deter-
equal to 5:1.
mine the applicability of regulatory limitations prior to use.
1.9 This international standard was developed in accor- 3.1.3 cavity walls, n—the inside surfaces of the concave
dance with internationally recognized principles on standard-
shape forming a cavity radiation source.
3.1.4 customer, n—the individual or institution to whom the
calibration or accuracy verification is being provided.
1
This test method is under the jurisdiction of ASTM Committee E20 on
Temperature Measurement and is the direct responsibility of Subcommittee E20.02
2
on Radiation Thermometry. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Nov. 1, 2021. Published December 2021. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 2011. Last previous edition approved in 2014 as E2847 – 14. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/E2847-21. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E2847−21
3.1.5 distance-to-size ratio (D:S), n—see field-of-view. 5. Significance and Use
3.1.6 effective emissivity, n—the ratio of the amount of
5.1 This test method
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E2847 − 14 E2847 − 21
Standard Test Method for
Calibration and Accuracy Verification of Wideband Infrared
1
Thermometers
This standard is issued under the fixed designation E2847; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers electronic instruments intended for measurement of temperature by detecting the intensity of thermal
radiation exchanged between the subject of measurement and the sensor.
1.2 The devices covered by this test method are referred to as infrared thermometers in this document.
1.3 The infrared thermometers covered in this test method are instruments that are intended to measure temperatures below
1000°C, measure thermal radiation over a wide bandwidth in the infrared region, and are direct-reading in temperature.
1.4 This guide test method covers best practice in calibrating infrared thermometers. It addresses concerns that will help the user
perform more accurate calibrations. It also provides a structure for calculation of uncertainties and reporting of calibration results
to include uncertainty.
1.5 Details on the design and construction of infrared thermometers are not covered in this test method.
1.6 This test method does not cover infrared thermometry above 1000°C. It does not address the use of narrowband infrared
thermometers or infrared thermometers that do not indicate temperature directly.
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.8 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.This standard does not purport to
address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish
appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.9 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
1
This practice test method is under the jurisdiction of ASTM Committee E20 on Temperature Measurement and is the direct responsibility of Subcommittee E20.02 on
Radiation Thermometry.
Current edition approved May 1, 2014Nov. 1, 2021. Published May 2014December 2021. Originally approved in 2011. Last previous edition approved in 20132014 as
ε1
E2847E2847 – 14.–13 . DOI: 10.1520/E2847–14.10.1520/E2847-21.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E2847 − 21
2. Referenced Documents
2
2.1 ASTM Standards:
E344 Terminology Relating to Thermometry and Hydrometry
E1256 Test Methods for Radiation Thermometers (Single Waveband Type)
E2758 Guide for Selection and Use of Wideband, Low Temperature Infrared Thermometers
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 cavity bottom, n—the portion of the cavity radiation source forming the end of the cavity.
3.1.1.1 Discussion—
The cavity bottom is the primary area where an infrared thermometer being calibrated measures radiation.
3.1.2 cavity radiation source, n—a concave shaped geometry approximating a perfect blackbody of controlled temperature and
defined emissivity used for calibration of radiation thermometers.
3.1.2.1 Discussion—
A cavity radiation source is a subset of thermal radiation sources.
3.1.2.2 Discussion—
To be a cavity radiation source of practical value for calibration, at least 90 % of the field-of-view of a radiation thermometer is
expected to be incident on the cavity bottom. In addition, the ratio of the length of the cavity versus the cavity diameter is expected
to be greater than or equal to 5:1.
3.1.3 cavity walls, n—the inside surfaces of the concave shape forming a cavity radiation source.
3.1.4 customer, n—the individual or institution to whom the calibration or accuracy verification is being pro
...