ASTM E1862-97(2002)e1

Standard Test Methods for Measuring and Compensating for Reflected Temperature Using Infrared Imaging Radiometers

SIGNIFICANCE AND USE
The infrared energy that is reflected by a specimen can cause measurement errors for an infrared thermographer measuring its surface temperature. Two test methods are provided for measuring and compensating for this reflected temperature error source, the Reflector Method and the Direct Method.
These test methods can be used in the field or laboratory using commonly available materials.
These test methods can be used with any infrared radiometers that have the required computer capabilities.
SCOPE
1.1 These test methods cover procedures for measuring and compensating for reflected temperature when measuring the surface temperature of a specimen with an infrared imaging radiometer.  
1.2 These test methods may involve use of equipment and materials in the presence of heated or electrically energized equipment, or both.  
1.3 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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Apr-1997
• ICS: 17.200.10 - Heat. Calorimetry
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.10 - Specialized NDT Methods

Relations

• Replaces: ASTM E1862-97e1 - Standard Test Methods for Measuring and Compensating for Reflected Temperature Using Infrared Imaging Radiometers
• Effective Date: 10-Apr-1997
• Replaced By: ASTM E1862-97(2010) - Standard Test Methods for Measuring and Compensating for Reflected Temperature Using Infrared Imaging Radiometers
• Effective Date: 01-May-2010
• Referred By: ASTM E2758-22 - Standard Guide for Selection and Use of Infrared Thermometers
• Effective Date: 10-Apr-1997
• Referred By: ASTM E2533-21 - Standard Guide for Nondestructive Examination of Polymer Matrix Composites Used in Aerospace Applications
• Effective Date: 10-Apr-1997

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
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Designation: E1862 – 97 (Reapproved 2002)
Standard Test Methods for
Measuring and Compensating for Reflected Temperature
Using Infrared Imaging Radiometers
This standard is issued under the fixed designation E1862; 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.
´ NOTE—Removed Footnote 2 in September 2002 since the organization is no longer in business.
1. Scope 3.1.5 specular reflector, n—a surface that produces a direct
image of a reflected source.
1.1 These test methods cover procedures for measuring and
3.2 See also Terminology E1316.
compensating for reflected temperature when measuring the
surface temperature of a specimen with an infrared imaging
4. Summary of Test Methods
radiometer.
4.1 Two test methods are given for measuring the reflected
1.2 These test methods may involve use of equipment and
temperature of a specimen, the Reflector Method and the
materials in the presence of heated or electrically energized
Direct Method.
equipment, or both.
4.2 A test method is also given for compensating for the
1.3 This standard does not purport to address all of the
error produced by reflected temperature using the computer
safety concerns, if any, associated with its use. It is the
built into an infrared imaging radiometer.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
5. Significance and Use
bility of regulatory limitations prior to use.
5.1 The infrared energy that is reflected by a specimen can
2. Referenced Documents cause measurement errors for an infrared thermographer mea-
2 suring its surface temperature. Two test methods are provided
2.1 ASTM Standards:
for measuring and compensating for this reflected temperature
E1316 Terminology for Nondestructive Examinations
error source, the Reflector Method and the Direct Method.
3. Terminology 5.2 These test methods can be used in the field or laboratory
using commonly available materials.
3.1 Definitions:
5.3 These test methods can be used with any infrared
3.1.1 diffuse reflector, n—a surface that produces a diffuse
radiometers that have the required computer capabilities.
image of a reflected source.
3.1.2 infrared thermographer, n—the person using an infra-
6. Interferences
red imaging radiometer.
6.1 Reflector Method:
3.1.3 infrared reflector, n—a material with a reflectance as
6.1.1 This test method uses an infrared reflector with an
close as possible to 1.00.
assumed reflectance of 1.00, which is an ideal property. Errors
3.1.4 reflected temperature, n—the temperature of the en-
can be minimized by using a reflector having a reflectance as
ergy incident upon and reflected from the measurement surface
close as possible to 1.00.
of a specimen.
6.1.2 Specimens vary in that they can be diffuse or spectral
reflectors, or both. Use of an infrared reflector with reflectance
These test methods are under the jurisdiction of ASTM Committee E07 on
properties as close as possible to those of the specimen will
Nondestructive Testing and are the direct responsibility of Subcommittee E07.10 on
reduce errors.
Emerging NDT Methods.
6.2 Direct Method:
Current edition approved April 10, 1997. Published June 1997. DOI: 10.1520/
E1862-97R02E01.
6.2.1 The Direct Method usually does not account for the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
heat from the infrared thermographer’s body as a source of
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
reflected temperature. If this heat source creates a significant
Standards volume information, refer to the standard’s Document Summary page on
error, use the Reflector Method.
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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E1862 – 97 (2002)
FIG. 1 Reflector Method
6.3 Reflected temperature errors produced by a point
source, such as the sun or a lamp, are difficult to measure
accurately.Theseerrorsourcescanoftenbeavoidedbymoving
the infrared imaging radiometer’s position and angle relative to
the specimen.
6.4 The measured reflected temperature of a specimen may
be specific to the waveband of the infrared imaging radiometer
used. Therefore, the infrared imaging radiometer’s waveband
should be noted with the measured value.
6.5 The significance of the error contributed by reflected
FIG. 2 Estimating the Angle of Reflection and Incidence
temperature can be estimated by shielding the specimen from
various angles and observing any changes in the thermal
image.
6.6 The error caused by reflected temperature can be re- This is the reflected temperature of this specimen when viewed
duced by shielding the specimen from the source of the from the position indicated in 8.1.2.
reflection.
8.1.6 Repeat 8.1.1-8.1.5 a minimum of three times and
average the temperatures to yield an average reflected tempera-
7. Apparatus
ture.
7.1 Calibrated Infrare
...