ASTM RRE3168

Annotation of standard text ASTM RRE3168 :

Reference Radiographs are nondestructive testing standards universally accepted because of their high reliability in accept-reject actions. These reference radiographs consist of five individual plates, each containing a series of radiographic images of 0.5 in. (12.7 mm) long slits in thin metal shims. The original radiographs used to prepare the illustrations were generated using various absorbers, geometric parameters (unsharpness, slit widths), and source parameters (kV, mA, time) to produce images of varying noise, contrast, and sharpness. Each radiographic image has a background density of 1.8 ± 0.15. Each visual acuity test plate consists of 25 individual image areas. The images are arranged in five rows and five columns. Each image area is 2 in. x 2 in. (51 mm x 51 mm). All identification is on the back side of the plate. Each plate can be viewed from any of the four orientations (that is, it can be viewed with any of the four edges “up” on the illuminator). Since there are five different plates in the set, this makes for a total of 20 different patterns that can be viewed. The identification of which of the five plates and which of the four orientations was viewed in any given test can be determined from the designation on the back side. A copy of the current ASTM standard is included with the purchase of these reference radiographs.