ASTM E1897-14(2022) PDF

Overview

ASTM E1897-14(2022) - Standard Practice for Measuring and Compensating for Transmittance of an Attenuating Medium Using Infrared Imaging Radiometers - provides established procedures for assessing and correcting the impact of attenuating media when using infrared imaging radiometers. Infrared thermographers frequently encounter semi-transparent materials such as windows, filters, and atmospheric layers, all of which can interfere with accurate temperature readings by reducing infrared radiation transmission. This standard outlines comprehensive test methods and guidance for both field and laboratory settings to ensure reliable temperature measurements and process control, particularly in nondestructive testing and evaluation contexts.

Key Topics

• Attenuating Medium and Infrared Measurement: Defines key concepts such as attenuating medium (any semi-transparent solid, liquid, or gas that reduces infrared radiation), blackbody simulator, emissivity, and reflected temperature.
• Transmittance Measurement: Procedures for accurately measuring the transmittance of a window, filter, or other medium, crucial for compensating measurement errors.
• Temperature Compensation Methods: Test methods for compensating for transmittance and emissivity errors depending on the available information, whether it is the known emissivity, known transmittance, or known specimen temperature.
• Practical Test Procedures: Step-by-step guidance for using calibrated infrared imaging radiometers and related equipment to assess transmittance and adjust measurement parameters.
• Process Control and Nondestructive Evaluation: Application of transmittance values to ensure precise process control and material evaluation.

Applications

The practical value of ASTM E1897-14(2022) lies in its robust applicability across many industries where infrared thermography serves as a critical nondestructive testing method. Common uses include:

• Industrial Inspections: Verifying temperature profiles through protective windows or filters in furnaces, electrical enclosures, and process vessels.
• Building Diagnostics: Measuring surface temperatures through glass or atmospheric conditions for energy audits, moisture analysis, or heat loss assessments.
• Materials Testing: Nondestructive evaluation of components where a transparent or semi-transparent barrier is present.
• Research and Development: Ensuring accuracy in experiments that require temperature measurements through various optical materials.
• Quality Assurance: Supporting QA processes where reliable temperature measurement is essential for product conformity and safety.

The standard allows practitioners to use widely available materials and infrared radiometers with computer capabilities, making it accessible in both controlled laboratory environments and field applications.

Related Standards

For a comprehensive approach to infrared imaging, nondestructive testing, and precise radiometric measurements, ASTM E1897-14(2022) is often used in conjunction with related standards, such as:

• ASTM E1316: Terminology for Nondestructive Examinations, which provides essential definitions for the terms used in ASTM E1897.
• Other Infrared Thermography Standards: Refer to ASTM and ISO documents regarding infrared testing methods and equipment specifications.
• Guidelines on Emissivity and Reflected Temperature: Supplementary documents and manufacturer guidance to enhance measurement accuracy in complex environments.

Summary

ASTM E1897-14(2022) establishes reliable procedures for measuring and compensating for the transmittance of attenuating media in infrared temperature measurement. It ensures precise temperature readings by addressing error sources associated with windows, filters, and atmospheric conditions, supporting process control and nondestructive evaluation in various technical fields. The standard's practical guidance helps maximize the value and reliability of infrared imaging radiometers, contributing to improved safety, quality, and efficiency in thermal measurements.