ASTM E1897-14(2018)

Standard Practice for Measuring and Compensating for Transmittance of an Attenuating Medium Using Infrared Imaging Radiometers

SIGNIFICANCE AND USE
5.1 The transmittance of an attenuating medium can cause errors for an infrared thermographer using an infrared imaging radiometer to measure the temperature of a specimen through the medium. Three test methods are given for measuring and compensating for this error source.  
5.1.1 A procedure is given for measuring the transmittance of an attenuating medium.  
5.1.2 A procedure is given for compensating for errors when measuring the temperature of a specimen having a known emissivity through an attenuating medium with a known transmittance.  
5.1.3 A procedure is given for measuring and compensating for transmittance and emissivity errors when the specimen temperature is known.  
5.2 These procedures can be used in the field or laboratory using commonly available materials.  
5.3 These procedures can be used with any infrared radiometers that have the required computer capabilities.  
5.4 The values of transmittance are defined only in terms of the procedure for the purpose of process control and nondestructive evaluation of materials.
SCOPE
1.1 This practice covers procedures for measuring and compensating for transmittance when using an infrared imaging radiometer to measure the temperature of a specimen through an attenuating medium, such as a window, filter, or atmosphere.2  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 These procedures may involve use of equipment and materials in the presence of heated or electrically-energized equipment, or both.  
1.4 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.  
1.5 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: Historical
• Publication Date: 31-Oct-2018
• ICS: 17.200.10 - Heat. Calorimetry
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.10 - Specialized NDT Methods

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E1897 − 14 (Reapproved 2018)
Standard Practice for
Measuring and Compensating for Transmittance of an
Attenuating Medium Using Infrared Imaging Radiometers
This standard is issued under the fixed designation E1897; 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 3. Terminology
3.1 Definitions of Terms Specific to This Standard:
1.1 This practice covers procedures for measuring and
3.1.1 attenuating medium—a semi-transparent solid, liquid,
compensating for transmittance when using an infrared imag-
or gas, such as a window, filter, external optics or an atmo-
ing radiometer to measure the temperature of a specimen
sphere that attenuates radiation.
through an attenuating medium, such as a window, filter, or
atmosphere.
3.1.2 blackbody simulator—a device with an emissivity
close to 1.00 that can be heated or cooled to a stable
1.2 The values stated in SI units are to be regarded as
temperature.
standard. No other units of measurement are included in this
standard. 3.1.3 filter—a semi-transparent material that attenuates cer-
tain wavelengths of radiation.
1.3 These procedures may involve use of equipment and
3.1.4 infrared thermographer—the person using an infrared
materials in the presence of heated or electrically-energized
imaging radiometer.
equipment, or both.
3.1.5 reflected temperature—the temperature of the energy
1.4 This standard does not purport to address all of the
incident upon and reflected by the measurement surface of the
safety concerns, if any, associated with its use. It is the
specimen.
responsibility of the user of this standard to establish appro-
3.1.6 window—a semi-transparent material that separates
priate safety, health, and environmental practices and deter-
conditioned and unconditioned atmospheres and attenuates
mine the applicability of regulatory limitations prior to use.
certain wavelengths of radiation.
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
3.2 See also Terminology E1316.
ization established in the Decision on Principles for the
4. Summary of Practice
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4.1 Using the computer built into an infrared imaging
Barriers to Trade (TBT) Committee.
radiometer, a method is given for measuring the transmittance
of an attenuating medium.
2. Referenced Documents
4.2 Using the computer built into an infrared imaging
2.1 ASTM Standards:
radiometer, a method is given for compensating for errors
E1316 Terminology for Nondestructive Examinations
when measuring the temperature of a specimen through an
attenuating medium when the emissivity of the specimen and
the transmittance of the attenuating medium are known.
This practice is under the jurisdiction of ASTM Committee E07 on Nonde-
4.3 Using the computer built into an infrared imaging
structive Testing and is the direct responsibility of Subcommittee E07.10 on
radiometer, a method is given for measuring and compensating
Specialized NDT Methods.
for unknown transmittance and emissivity errors when the
Current edition approved Nov. 1, 2018. Published December 2018. Originally
specimen temperature is known.
approved in 1997. Last previous edition approved in 2014 as E1897 – 14. DOI:
10.1520/E1897-14R18.
This practice was originally adapted in 1997, by agreement, from the Guideline
5. Significance and Use
for Measuring and Compensating for Reflected Temperature, Emittance and
5.1 The transmittance of an attenuating medium can cause
Transmittance developed by Infraspection Institute, 425 Ellis Street, Burlington, NJ
08016.
errors for an infrared thermographer using an infrared imaging
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
radiometer to measure the temperature of a specimen through
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
the medium. Three test methods are given for measuring and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. compensating for this error source.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1897 − 14 (2018)
5.1.1 A procedure is given for measuring the transmittance 7.2 The procedure for measuring the transmittance of an
of an attenuating medium. attenuating medium requires a tripod or device to support the
5.1.2 Aprocedureisgivenforcompensatingforerrorswhen infrared imaging radiometer.
measuring the temperature of a specimen having a known
7.3 The procedure for measuring the transmittance of an
emissivity through an attenuating medium with a known
attenuating medium requires a high-emissivity source that is
transmittance.
heated to a stable temperature at least 20 °C above ambient
5.1.3 Aprocedure is given for measuring and compensating
temperature.
for transmittance and emissivity errors when the specimen
7.4 The procedure for measuring and compensating for
temperature is known.
unknown transmittance and emissivity errors when the speci-
5.2 These procedures can be used in the field or laboratory
men temperature is known requires a calibrated thermometer to
using commonly available materials.
measure the temperature of the specimen.
5.3 These procedures can be used with any infrared radi-
ometers that have the required computer capabilities.
8. Procedure
5.4 The values of transmittance are defined only in terms of
8.1 To measure the transmittance of an attenuating medium,
the procedure for the purpose of process control and nonde-
use the following sequential steps:
structive evaluation of materials.
8.1.1 Place the infrared imaging radiometer on the tripod or
support device at the desired location and distance from the
6. Interferences
blackbody simulator.
6.1 Practice for Measuring the Transmittance of an Attenu-
8.1.2 Point the infrared imaging radiometer at the black-
ating Medium:
body simulator and focus on a portion that has an emissivity of
6.1.1 This practice requires a blackbody simulator with an
0.95 or greater. Make sure that the blackbody simulator is at a
emissivity of 0.95 or greater that is at least 20 °C warmer than
stable temperature at least 20 °C above the ambient tempera-
ambient temperature. Potential errors can be minimized by
ture.
ensuring the stability of the temperature difference between the
8.1.3 Use an appropriate infrared imaging radiometer mea-
sourceandtheambienttemperatureduringtheprocedure.Also,
surement function (such as spot temperature, crosshairs, or
the transmittance meas
...

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: E1897 − 14 E1897 − 14 (Reapproved 2018)
Standard Practice for
Measuring and Compensating for Transmittance of an
Attenuating Medium Using Infrared Imaging Radiometers
This standard is issued under the fixed designation E1897; 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*Scope
1.1 This practice covers procedures for measuring and compensating for transmittance when using an infrared imaging
radiometer to measure the temperature of a specimen through an attenuating medium, such as a window, filter, or atmosphere.
1.2 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.
1.3 These procedures may involve use of equipment and materials in the presence of heated or electrically-energized equipment,
or both.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 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.
2. Referenced Documents
2.1 ASTM Standards:
E1316 Terminology for Nondestructive Examinations
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 attenuating medium—a semi-transparent solid, liquid, or gas, such as a window, filter, external optics or an atmosphere
that attenuates radiation.
3.1.2 blackbody simulator—a device with an emissivity close to 1.00 that can be heated or cooled to a stable temperature.
3.1.3 filter—a semi-transparent material that attenuates certain wavelengths of radiation.
3.1.4 infrared thermographer—the person using an infrared imaging radiometer.
3.1.5 reflected temperature—the temperature of the energy incident upon and reflected by the measurement surface of the
specimen.
3.1.6 window—a semi-transparent material that separates conditioned and unconditioned atmospheres and attenuates certain
wavelengths of radiation.
3.2 See also Terminology E1316.
4. Summary of Practice
4.1 Using the computer built into an infrared imaging radiometer, a method is given for measuring the transmittance of an
attenuating medium.
This practice is under the jurisdiction of ASTM Committee E07 on Nondestructive Testing and is the direct responsibility of Subcommittee E07.10 on Specialized NDT
Methods.
Current edition approved Dec. 1, 2014Nov. 1, 2018. Published December 2014December 2018. Originally approved in 1997. Last previous edition approved in 20102014
as E1897 – 97 (2010).E1897 – 14. DOI: 10.1520/E1897-14.10.1520/E1897-14R18.
This practice was originally adapted in 1997, by agreement, from the Guideline for Measuring and Compensating for Reflected Temperature, Emittance and
Transmittance developed by Infraspection Institute, 425 Ellis Street, Burlington, NJ 08016.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1897 − 14 (2018)
4.2 Using the computer built into an infrared imaging radiometer, a method is given for compensating for errors when
measuring the temperature of a specimen through an attenuating medium when the emissivity of the specimen and the
transmittance of the attenuating medium are known.
4.3 Using the computer built into an infrared imaging radiometer, a method is given for measuring and compensating for
unknown transmittance and emissivity errors when the specimen temperature is known.
5. Significance and Use
5.1 The transmittance of an attenuating medium can cause errors for an infrared thermographer using an infrared imaging
radiometer to measure the temperature of a specimen through the medium. Three test methods are given for measuring and
compensating for this error source.
5.1.1 A procedure is given for measuring the transmittance of an attenuating medium.
5.1.2 A procedure is given for compensating for errors when measuring the temperature of a specimen having a known
emissivity through an attenuating medium with a known transmittance.
5.1.3 A procedure is given for measuring and compensating for transmittance and emissivity errors when the specimen
temperature is known.
5.2 These procedures can be used in the field or laboratory using commonly available materials.
5.3 These procedures can be used with any infrared radiometers that have the required computer capabilities.
5.4 The values of transmittance are defined only in terms of the procedure for the purpose of process control and nondestructive
evaluation of materials.
6. Interferences
6.1 Practice for Measuring the Transmittance of an Attenuating Medium:
6.1.1 This practice requires a blackbody simulator with an emissivity of 0.95 or greater that is at least 20°C20 °C warmer than
ambient temperature. Potential errors can be minimized by ensuring the stability of the temperature difference between the source
and the ambient temperature during the procedure. Also, the transmittance measurement accuracy can be increased by increasing
this temperature difference.
6.1.2 Errors can be minimized by ensuring that the temperature of the attenuating medium is as close as possible to the reflected
temperature incident upon the specimen.
6.1.3 The compositions and thicknesses of attenuating media can vary within the same specimen. Errors can be minimized by
measuring through the same portion of the specimen every time.
6.2 Practice for Compensating for Unknown Errors When Measuring the Temperature of a Specimen With a Known Emissivity
Through an Attenuating Medium Having a Known Transmittance:
6.2.1 Errors can be minimized by ensuring that the temperature of the attenuating medium is as close as possible to the reflected
temperature incident upon the specimen.
6.3 The transmittance of an attenuating medium may be specific to the temperature of the medium and the spectral waveband
of the radiometer used to make the measurement. Therefore, the temperature of the measured specimen and the spectral waveband
of the radiometer used should be noted with the measured transmittance value.
6.4 The use of these test methods to compensate for the transmittance of an attenuating medium is valid only when measuring
the temperatures of specimens that are
...