ASTM E2847-11

This guide provides guidelines and basic test methods for the accuracy verification of infrared thermometers. It includes test set-up and calculation of uncertainties. It is intended to provide the user with a consistent method, while remaining flexible in the choice of calibration equipment. It is understood that the uncertainty obtained depends in large part upon the apparatus and instrumentation used. Therefore, since this guide is not prescriptive in approach, it provides detailed instruction in uncertainty evaluation to accommodate the variety of apparatus and instrumentation that may be employed.

This guide is intended primarily for calibrating handheld infrared thermometers. However, the techniques described in this guide may also be appropriate for calibrating other classes of radiation thermometers. It may also be of help to those calibrating thermal imagers.

This guide specifies the necessary elements of the report of calibration for an infrared thermometer. The required elements are intended as a communication tool to help the end user of these instruments make accurate measurements. The elements also provide enough information, so that the results of the calibration can be reproduced in a separate laboratory.

1.1 This guide covers electronic instruments intended for measurement of temperature by detecting the intensity of thermal radiation exchanged between the subject of measurement and the sensor.

1.2 The devices covered by this guide are referred to as infrared thermometers in this document.

1.3 The infrared thermometers covered in this guide are instruments that are intended to measure temperatures below 1000°C, measure thermal radiation over a wide bandwidth in the infrared region, and are direct-reading in temperature.

1.4 This guide covers best practice in calibrating infrared thermometers. It addresses concerns that will help the user perform more accurate calibrations. It also provides a structure for calculation of uncertainties and reporting of calibration results to include uncertainty.

1.5 Details on the design and construction of infrared thermometers are not covered in this guide.

1.6 This guide does not cover infrared thermometry above 1000°C. It does not address the use of narrowband infrared thermometers or infrared thermometers that do not indicate temperature directly.

1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.8 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.