ASTM E 1114 - 92. Standard Test Method for Determining the Focal Size of Iridium-192 Industrial Radiographic Sources

American Society for Testing and Materials (ASTM). Reapproved 1997, 4 pages.
This test method covers the determination of the focal size of an iridium-192 radiographic source. The determination is based upon measurement of the image of the iridium metal source in a projection radiograph of the source assembly and comparison to the measurement of the image of a reference sample in the same radiograph.