1.1 These reference photographs are supplied as a means of establishing types and characteristics of surface discontinuities detectable by the penetrant inspection methods. They may be used as a reference for acceptance standards, specifications and drawings.

1.2 Actual dimensions including maximum length of indications and number of indications per unit area must be specified by the users of this document. No attempt has been made to establish limits of acceptability or the metallurgical cause of a discontinuity.