Using colour photographs, the Standard describes four grades of rust for steel surfaces, and a number of preparation grades achievable when preparing a surface by either blast cleaning, hand and power tool cleaning, or flame cleaning methods. The Standard ISO 8501-1:1988 is based on Swedish Standard SIS 05 59 00:1967 and DIN 55 928, Part 4, Supplement 1:1978. In addition to the photographic examples present in the superseded Standard, it contains four photographs and descriptions of flame-cleaned surfaces.