This guide describes the use of reference photographs depicting the appearance of both previously unpainted and previously painted and partially rusted hot-rolled carbon steel prior to and after abrasive blast cleaning. These photographs are intended to be used to supplement the written SSPC/NACE International blast cleaning surface preparation standards. The written standards are the primary means to determine conformance with blast cleaning requirements. The photographs shall not be used as a substitute for the written standards (see Note 7.1).