CSN EN ISO 16823 This document specifies the principles of ultrasonic through-transmission techniques. Through-transmission techniques can be used for: - detection of discontinuities; - determination of sound 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 the testing of flat products, e.g. plates and sheets. Further, it can be used for tests, for example: - where the shape, dimensions or orientation of possible discontinuities are unfavourable for direct reflection; - of materials with high sound attenuation; - on thin test objects. Original English text of CSN EN Standard. The price of the Standard included all amendments and correcturs.