ASTM E 3362 : 2026

1.1This guide covers the most common questions about reference radiographs and digital reference images and their use. Reference radiographs and digital reference images are used throughout industry to create acceptance specifications by identifying, categorizing, and grading discontinuities in relation to their radiographic appearance.

1.2Reference radiographs of castings and weldments are film radiographs that are viewed on a film illuminator and compared to a film radiograph of a production part such that discontinuities in the production part can be identified and graded for severity. Reference radiographs are not to be compared to digital radiographs.

1.3Digital reference images of castings and weldments are digitized from the same film radiographs as the reference radiographs, loaded on to DVD media, and are viewed on a digital display at a user-selected resolution and compared to a digital radiograph viewed on a digital display such that discontinuities in the production part can be identified and graded for severity. Digital reference images are not to be compared to film radiographs.

1.4Reference radiographs and digital reference images assist the interpreter by replacing a word specification with a radiograph illustration of real indications in real radiographs. There are several sets of reference radiographs. They can be grouped into five categories: castings, weldments, demonstrations, film digitization, and visual acuity. This guide explains the categories and how reference radiographs are used.

1.5All versions of reference radiographs are the same regardless of age or packaging or mounting style. For example, Reference Radiographs E505 purchased when first approved in 1974 are the exact same as those purchased now and in the future.

1.6Table X1.1 in Appendix X1 lists all ASTM reference radiograph and digital reference image standards.

1.7Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.

1.8This 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.

1.9This 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.