ASTM E1862-14(2022)

Standard Practice for Measuring and Compensating for Reflected Temperature Using Infrared Imaging Radiometers

SIGNIFICANCE AND USE
5.1 The infrared energy that is reflected by a specimen can cause measurement errors for an infrared thermographer measuring its surface temperature. Two procedures are provided for measuring and compensating for this reflected temperature error source, the Reflector Method and the Direct Method.  
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 Due to the nature of the specimens, the repeatability and reproducibility are subjective. However, a measure of the precision of the procedures can be inferred from the results of the replicate procedures specified in 8.1.6 and 8.2.7.
SCOPE
1.1 This practice covers procedures for measuring and compensating for reflected temperature when measuring the surface temperature of a specimen with an infrared imaging radiometer.2  
1.2 These procedures 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 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: 30-Nov-2022
• ICS: 17.200.10 - Heat. Calorimetry
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.10 - Specialized NDT Methods

Relations

• Refers: ASTM E1316-24 - Standard Terminology for <?Pub Dtl?>Nondestructive Examinations
• Effective Date: 01-Feb-2024
• Refers: ASTM E1316-19b - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2019
• Refers: ASTM E1316-19 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Mar-2019
• Refers: ASTM E1316-18 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jan-2018
• Refers: ASTM E1316-17a - Standard Terminology for Nondestructive Examinations
• Effective Date: 15-Jun-2017
• Refers: ASTM E1316-17 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Feb-2017
• Refers: ASTM E1316-16a - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Aug-2016
• Refers: ASTM E1316-16 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Feb-2016
• Refers: ASTM E1316-15a - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2015
• Refers: ASTM E1316-15 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Sep-2015
• Refers: ASTM E1316-14e1 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jun-2014
• Refers: ASTM E1316-14 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jun-2014
• Refers: ASTM E1316-13d - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2013
• Refers: ASTM E1316-13c - Standard Terminology for Nondestructive Examinations
• Effective Date: 15-Jun-2013
• Refers: ASTM E1316-13b - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jun-2013

Overview

ASTM E1862-14(2022) is the recognized international standard for measuring and compensating for reflected temperature using infrared imaging radiometers. Published by ASTM International, this standard outlines practical procedures to identify and mitigate errors in surface temperature measurements caused by reflected infrared energy. Such errors are critical for professionals and organizations employing infrared thermography in nondestructive testing (NDT), quality assurance, and maintenance across various industries.

Infrared thermographers often face challenges when reflected energy from surrounding sources distorts their temperature readings. ASTM E1862 provides two validated approaches-the Reflector Method and the Direct Method-to accurately quantify and compensate for these reflected temperature errors, ensuring reliable and accurate surface temperature measurements.

Key Topics

• Reflected Temperature Error: Addresses how infrared energy, reflected from specimen surfaces, can cause significant inaccuracies in measured temperatures.
• Practical Procedures: Presents two field- and laboratory-ready methods:
  • Reflector Method: Utilizes an infrared reflector with high reflectance, closely matching the specimen's properties.
  • Direct Method: Estimates reflected temperature directly through the infrared imaging radiometer, adjusted for angle and distance.
• Required Equipment:
  • Calibrated infrared imaging radiometer with computer control.
  • Infrared reflector (e.g., aluminum foil or metal plate).
  • Tripod or stable mounting device.
• Measurement and Compensation: Guidance on collecting repeatable data, averaging results, and inputting compensatory values into the device’s interface (commonly labeled as "Reflected Temperature" or "Ambient Temperature").
• Limitations: Notes that specimen characteristics and environmental conditions affect repeatability and reproducibility; encourages multiple trials for accuracy.
• Safety and Best Practices: Recommends safety precautions around energized or heated equipment and advises compliance with relevant health and environmental regulations.

Applications

ASTM E1862 is designed for wide application wherever nondestructive temperature measurement with infrared radiometry is required:

• Nondestructive Testing (NDT): Assists inspectors in identifying equipment faults, thermal insulation failures, and electrical anomalies by delivering precise surface temperature data.
• Predictive Maintenance: Enables maintenance teams to monitor critical assets, preventing unexpected failures due to undetected thermal irregularities.
• Quality Assurance: Used in manufacturing and process industries for the verification of thermal treatments, coatings, or assemblies.
• Research and Development: Supports laboratories and R&D teams in accurately characterizing materials and components using infrared thermography.
• Facility and Building Inspections: Employed in energy audits and building diagnostics to detect heat loss, moisture intrusion, or HVAC inefficiencies.

Related Standards

For a comprehensive approach to infrared thermography and nondestructive examinations, consider referencing these related ASTM standards:

• ASTM E1316: Terminology for Nondestructive Examinations-provides key definitions to ensure consistent interpretation of NDT practices.
• Other ASTM Infrared Testing Standards: Look for standards on equipment calibration, test methods for specific materials, or procedures for different radiometry applications.

By implementing ASTM E1862-14(2022), organizations benefit from improved accuracy in temperature measurement, reduced error from reflected energy, enhanced safety, and global compliance with recognized best practices in infrared imaging and nondestructive testing.

Keywords: ASTM E1862, reflected temperature, infrared imaging radiometer, infrared thermography, nondestructive testing, temperature compensation, radiometry, surface temperature measurement, quality assurance, predictive maintenance.

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: E1862 −14 (Reapproved 2022)
Standard Practice 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.
1. Scope 3.1.2 infrared reflector, n—a material with a reflectance as
close as possible to 1.00.
1.1 This practice covers procedures for measuring and
3.1.3 infrared thermographer, n—the person using an infra-
compensating for reflected temperature when measuring the
red imaging radiometer.
surface temperature of a specimen with an infrared imaging
radiometer.
3.1.4 reflected temperature, n—the temperature of the en-
ergy incident upon and reflected from the measurement surface
1.2 These procedures may involve use of equipment and
of a specimen.
materials in the presence of heated or electrically energized
equipment, or both.
3.1.5 specular reflector, n—a surface that produces a direct
image of a reflected source.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.2 See also Terminology E1316.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter- 4. Summary of Procedure
mine the applicability of regulatory limitations prior to use.
4.1 Two procedures are given for measuring the reflected
1.4 This international standard was developed in accor-
temperature of a specimen, the Reflector Method and the
dance with internationally recognized principles on standard-
Direct Method.
ization established in the Decision on Principles for the
4.2 Aprocedure is also given for compensating for the error
Development of International Standards, Guides and Recom-
produced by reflected temperature using the computer built
mendations issued by the World Trade Organization Technical
into an infrared imaging radiometer.
Barriers to Trade (TBT) Committee.
5. Significance and Use
2. Referenced Documents
5.1 The infrared energy that is reflected by a specimen can
2.1 ASTM Standards:
cause measurement errors for an infrared thermographer mea-
E1316 Terminology for Nondestructive Examinations
suringitssurfacetemperature.Twoproceduresareprovidedfor
measuring and compensating for this reflected temperature
3. Terminology
error source, the Reflector Method and the Direct Method.
3.1 Definitions:
5.2 These procedures can be used in the field or laboratory
3.1.1 diffuse reflector, n—a surface that produces a diffuse
using commonly available materials.
image of a reflected source.
5.3 These procedures can be used with any infrared radi-
ometers that have the required computer capabilities.
This practice is under the jurisdiction of ASTM Committee E07 on Nonde-
5.4 Due to the nature of the specimens, the repeatability and
structive Testing and is the direct responsibility of Subcommittee E07.10 on
reproducibility are subjective. However, a measure of the
Specialized NDT Methods.
precision of the procedures can be inferred from the results of
Current edition approved Dec. 1, 2022. Published December 2022. Originally
the replicate procedures specified in 8.1.6 and 8.2.7.
approved in 1997. Last previous edition approved in 2018 as E1862 – 14(2018).
DOI:10.1520/E1862-14R22.
This practice was originally adapted in 1997, by agreement, from the Guideline
6. Interferences
for Measuring and Compensating for Reflected Temperature, Emittance and
6.1 Reflector Method:
Transmittance developed by Infraspection Institute, 425 Ellis Street, Burlington, NJ
08016.
6.1.1 This procedure uses an infrared reflector with an
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
assumed reflectance of 1.00, which is an ideal property. Errors
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
can be minimized by using a reflector having a reflectance as
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. close as possible to 1.00.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1862 − 14 (2022)
FIG. 1 Reflector Method
6.1.2 Specimens vary in that they can be diffuse or spectral 8.1.2 Place the infrared imaging radiometer on the tripod or
reflectors, or both. Use of an infrared reflector with reflectance support device at the desired location and distance from the
properties as close as possible to those of the specimen will specimen.
reduce errors. 8.1.3 Point the infrared imaging radiometer at the specimen
and focus on the portion of the specimen where the reflected
6.2 Direct Method:
temperature is to be measured.
6.2.1 The Direct Method usually does not account for the
8.1.4 Place the infrared reflector in front of, and parallel to,
heat from the infrared thermographer’s body as a source of
the specimen (see Fig. 1). Maintain a safe working distance
reflected temperature. If this heat source creates a significant
error, use the Reflector Method.
6.3 Reflected temper
...