ASTM E1543-14 (2022) PDF

Full title and description

ASTM E1543-14 (Reapproved 2022) — Standard Practice for Noise Equivalent Temperature Difference of Thermal Imaging Systems. This practice defines procedures for determining the noise equivalent temperature difference (NETD or NEΔT) — a measure of temperature sensitivity — for conventional forward-looking infrared (FLIR) and other opto-mechanical scanned thermal imaging systems (excludes CCDs and pyroelectric vidicons).

Abstract

This practice describes a laboratory method using a uniform blackbody target and background to measure the peak-to-peak target signal and the RMS background noise across a reference filter, and from those values to calculate NETD (NEΔT). It is intended to provide an objective, repeatable measure of a thermal imaging system’s temperature sensitivity (detector and preamplifier emphasis) under specified conditions (standard background temperature 295 K / 22 °C).

General information

• Status: Current (reapproved 2022).
• Publication date: December 1, 2022 (E1543‑14 reapproval published 2022).
• Publisher: ASTM International.
• ICS / categories: Temperature-measuring instruments; nondestructive testing / thermography (ICS 17.200.20).
• Edition / version: E1543‑14 (original designation year 2014), reapproved 2022 (designation shown as E1543‑14(2022)).
• Number of pages: 4 pages.

Key bibliographic and status details above are drawn from the ASTM/standards record and product listings for the E1543‑14(2022) reapproval.

Scope

This practice covers determination of NETD (NEΔT) for thermal imaging systems that use optical‑mechanical scanning (FLIR and similar). It specifies test conditions (including a photonic detector assumption at 295 K / 22 °C), referenced measurement filters, and measurement of target signal and background noise to compute NETD. The practice does not address charge‑coupled devices or pyroelectric vidicons and does not attempt to address all safety concerns associated with testing.

Key topics and requirements

• Definition and purpose of NETD (NEΔT) as the temperature sensitivity metric for thermal imaging detectors and preamplifiers.
• Test setup: uniform blackbody simulator viewed through a prescribed aperture and standard reference filter.
• Measurements required: peak‑to‑peak target signal voltage, RMS background noise voltage, and target/background temperatures across the reference filter.
• Calculation method for NETD from measured signal and noise values, including conditions for dwell time and frame scanning.
• Limitations and applicability: intended for opto‑mechanically scanned thermal imagers (FLIR type); specifically excludes CCD and pyroelectric vidicon detectors; laboratory conditions (standard background temperature 295 K) may not match field performance.

These topics and procedural requirements are taken from the ASTM practice text and supporting summaries.

Typical use and users

This practice is used by thermal imaging manufacturers and designers to specify and verify detector/receiver temperature sensitivity; by calibration and test laboratories that characterize camera performance; and by nondestructive testing (NDT) practitioners, procurement engineers, and researchers who need objective NETD values for comparison, acceptance testing, or specifications. It is most relevant in laboratory performance testing rather than direct field‑service evaluation.

Related standards

ASTM E1543 is commonly referenced alongside other thermal imaging practices and terminology, including E1213 (Minimum Resolvable Temperature Difference), E1311 (Minimum Detectable Temperature Difference), E1933 (Measuring and Compensating for Emissivity), and E1862/E1897 series for reflected/transmittance compensation; terminology references such as E1316 also apply. These related standards form the suite of ASTM practices for infrared thermography and NDT.

Keywords

NETD, NEΔT, noise equivalent temperature difference, thermal imaging, FLIR, infrared thermography, blackbody simulator, detector sensitivity, nondestructive testing, temperature‑measuring instruments.

FAQ

Q: What is this standard?

A: ASTM E1543‑14(2022) is a Standard Practice that specifies laboratory methods to determine the noise equivalent temperature difference (NETD or NEΔT) of thermal imaging systems that use optical‑mechanical scanning.

Q: What does it cover?

A: It covers test configuration, definitions (blackbody simulator, dwell time, etc.), measurement of target signal and background noise across a reference filter, and calculation of NETD. It assumes a photonic detector at a standard background temperature of 295 K (22 °C) and excludes CCDs and pyroelectric vidicons.

Q: Who typically uses it?

A: Manufacturers, test and calibration laboratories, NDT practitioners, procurement/specification engineers, and researchers comparing or specifying thermal camera temperature sensitivity.

Q: Is it current or superseded?

A: The designation appears as E1543‑14 with reapproval in 2022 (published December 1, 2022). As of the reapproval date the practice is current; users should confirm there has been no subsequent revision or withdrawal after December 1, 2022 when applying the standard.

Q: Is it part of a series?

A: Yes — it is part of ASTM’s suite of thermal‑imaging/NDT practices (for example, E1213, E1311, E1933, E1862, and related terminology E1316) that together address performance, sensitivity, emissivity, reflected/transmitted temperature compensation, and definitions for infrared thermography.

Q: What are the key keywords?

A: NETD, NEΔT, noise equivalent temperature difference, thermal imaging systems, FLIR, blackbody simulator, detector sensitivity, thermography, NDT.