ASTM/ISO 51539-23 - 1.12.2020
Significance and Use

4.1?Indicators may be used to show that products have been exposed to a radiation source. They should be used only to provide a qualitative indication of radiation exposure and may be used to distinguish process loads that have been irradiated from unirradiated loads.

Note 1:?The use of indicators does not eliminate the need for other process-control procedures, such as quantitative dosimetry or the controlled segregation of irradiated from nonirradiated products.

Note 2:?See ISO/ASTM Standards 51608, 51649, 51702, 51939, and 51940 for information on the use of indicators in the various types of processing facilities and for unique product applications.

4.2?The indicator manufacturer is obliged to supply a statement regarding the approximate dose level at which the examiner (20/20 vision), at standard illumination (unfiltered daylight, or artificial light of the spectrum and intensity defined by the proper ASTM standard), is able to determine the visual change in the indicator.

1. Scope

1.1?This document covers procedures for using radiation-sensitive indicators (referred to hereafter as indicators) in radiation processing. These indicators may be labels, papers, inks or packaging materials which undergo a visual change when exposed to ionizing radiation (1-5).2

1.2?The purpose for using indicators is to determine visually whether or not a product has been irradiated, rather than to measure different dose levels.

1.3?Indicators are not dosimeters and should not be used as a substitute for proper dosimetry. Information about dosimetry systems for radiation processing is provided in other ASTM and ISO/ASTM documents (see ISO/ASTM Guide 51261).

1.4?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.

1.5?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.