This International Standard describes a method for carrying out an indentation test on a single coating or multicoat system of paint, varnish or related product, using a Buchholz indentor. The length of the indentation produced is indicative of the residual deformation of the coating. This indentation test is not suitable for products which contain a strong plasticizer. NOTE 1 Since the indentation test, like other physical tests on paints, gives results which can be dependent upon time, temperature and humidity, comparable results will only be obtained if the test is carried out under well-defined conditions. NOTE 2 Since the indentation depth depends upon the film thickness, the result obtained for the indentation length is only valid if the coating thickness exceeds a certain minimum value (see Annex A).