This European Standard specifies a method to assess the sensitivity of natural stones when exposed to accidental staining. It defines a procedure for the application of the stains, the cleaning and the assessment of the surface appearance after cleaning. It also covers the possibility to assess the efficiency of a surface treatment. Note that the method does not intend to present any de-staining technique. A defined set of staining agents is applied on a defined stone surface. The mode of application is specified. The specimens are conditioned and washed with a standardised cleaning machine. The stones are dried and the possible remainders of the stains are assessed by a visual observation. The test standard is directed at manufacturers and suppliers of natural stone as well as independent test laboratories. The committee responsible for this standard is NA 062-03-11 GA "Gemeinschaftsarbeitsausschuss NMP/NABau: Naturwerkstein; Anforderungen, Prüfverfahren und Terminologie" ("Joint Working Committee NMP/NABau: Natural stone; requirements, test methods and terminology") at DIN.