BS EN 462-5:1996 Non - destructive testing - Image quality of radiographs Part 5. Image quality indicators ( duplex wire type ), determination of image unsharpness value
2013BS EN ISO 19232-5:2013 Non-destructive testing. Image quality of radiographs. Determination of the image unsharpness value using duplex wire-type image quality indicators
1970BS EN 462-5:1996 Non - destructive testing - Image quality of radiographs Part 5. Image quality indicators ( duplex wire type ), determination of image unsharpness value