ISO 16823:2012 specifies the principles of through-transmission techniques.
Through-transmission techniques can be used for: a) detection of imperfections; b) determination of attenuation.
The general principles required for the use of ultrasonic testing of industrial products are described in ISO 16810.
The through-transmission technique is used for testing of flat products, e.g. plates and sheets.
Further, it is used for testings e.g.: 1) where the shape, dimensions or orientation of possible imperfections are unfavourable for direct reflection; 2) in materials with high attenuation; 3) in thin products.