1.1 These reference radiographs illustrate the categories and severity levels of discontinuities that may occur in aluminum-alloy and magnesium-alloy die castings. They are intended to provide: 1.1.1 A guide enabling recognition of discontinuities and their differentiation both as to type and severity level through radiographic examination. 1.1.2 Example radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications, and drawings. 1.1.3 The values stated in inch-pounds are to be regarded as standard. Note 1The set of reference radiographs consists of five 81/2 by 11-in. cardboard frames containing radiographs covering discontinuities in aluminum and magnesium alloy die castings. The first four frames each contain two sets of four graded levels of increasing severity, while the last frame contains two ungraded radiographs. The 5 frames are contained in a 101/2 by 111/2-in. ring binder. Note 2Reference radiographs applicable to aluminum and magnesium castings up to 2 in. (50 mm) in thickness are contained in ASTM Reference Radiographs E 155, for Inspection of Aluminum and Magnesium Castings, Volumes I and II. 1.2 Two kinds of illustration categories are covered as follows: 1.2.1 Graded - Three discontinuity categories for aluminum die castings and three discontinuity categories for magnesium die castings, each illustrated in four levels of progressively increasing severity. Category A discontinuities are illustrated for aluminum and magnesium die castings having thicknesses of 1/8in. (3.2 mm) and 5/8 in. (15.9 mm); Category B discontinuities are illustrated for 1/ 8-in. thick aluminum and magnesium die castings; and Category C discontinuities are illustrated for 5/8-in. thick aluminum and magnesium die castings. 1.2.2 Ungraded - One illustration of one discontinuity for 0.20-in. (5.1-mm) thickness aluminum die casting; and one illustration of one discontinuity for 1/8-in. (3.2-mm) thickness magnesium die casting. 1.3 This document may be used for other materials, thicknesses, or with other energy levels for which it has been found to be applicable and agreement has been reached between the purchaser and manufacturer. 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 and health practices and determine the applicability of regulatory limitations prior to use.