NBN EN ISO 3452-3:1999

This European standard describes two types of reference blocks: - Type 1 reference blocks are used to determine the sensitivity levels of both fluorescent and colour contrast penetrant product families; - Type 2 reference blocks are used for routine assessment of the performance of both fluorescent and colour contrast penetrant facilities and part-used containers. The reference blocks are used in the same conditions as the pieces to be tested according to EN 571-1.