Purpose: This Aerospace Standard establishes an identification system and provides design and tolerance information in describing two series of image quality indicators currently used in radiography of aerospace components@ especially in electronic component evaluation and radiographic film and paper classification. Classification: Individual image quality indicators (IQIs) are classified by use of this standard number@ followed by appropriate codes@ as shown in Table I. Synopsis of the classification system is: AS 1613-A-XX IQI shown in Fig. 1@ with six tungsten wires AS 1613-B-XX IQI shown in Fig. 2@ with six tungsten wires and six lead beads.