Preparation of steel substrates before application of paints and similar products. Visual assessment of surface cleanliness. Part 1: Notching stages and preparation stages for uncoated steel substrate and steel substrate after complete removal of previous coatings. The standard visually assesses the degree of rusting and cleanliness of uncoated steel. The standard is also known as the Swedish standard for blasting grades with cleanliness values in Sa and manual surface preparation by mechanized means in St. The standard contains high quality photographs for evaluating the degree of rusting and cleanliness after manual and mechanical cleaning or cleanliness after blasting. The different grades are defined by verbal descriptions along with photographic illustrations that are representative examples within the tolerance range for each grade as verbally described. It is applicable for hot rolled steel surface ready for painting by methods such as blasting, manual or mechanized cleaning and flame cleaning.