This International Standard specifies a destructive method for determination of the dry film thickness, in which damage to the coat caused in a definite manner is evaluated microscopically. The method is suitable for almost all coat-substrate combinations and also allows determination of the single film thicknesses of coating systems. The method cannot be applied or can only be applied with restrictions in case of too soft and/or elastic coatings (no recognizable scribe or drill hole can be observed), hard (cannot be scribed/drilled) or too soft and/or elastic substrates, too low visual contrast between the coating and substrate, and film thicknesses that are larger than the depth of field of the measuring microscope.