1.1 This part of ISO 12137 is one of a series of standards dealing with the sampling and testing of paints, varnishes and related products.

It specifies a method for determining, using a curved (loop-shaped or ring-shaped) stylus, the mar resistance of a single coating of a paint, varnish or related product, or the upper layer of a multicoat system. Part 2 of ISO 12137 specifies a method using a pointed stylus. The choice between the two methods will depend on the particular practical problem.

1.2 This test has been found to be useful in comparing the mar resistance of different coatings. It is most useful in providing relative ratings for a series of coated panels exhibiting significant differences in mar resistance.