Standard - Preparation of steel substrates before application of paints and related products - Visual assessment of surface cleanliness - Informative supplement to Part 1: Representative photographic exemples of the change of appearance imparted to steel when blast-cleaned with different abrasives (SO 8501-1:1988/Suppl:1994) SS-EN ISO 8501-1/Suppl:2001 - Swedish Institute for Standards, SIS