This International Standard specifies a method for determining and expressing quantitatively the brittleness of photographic film and papers. It does not, however, specify a universal brittleness test for all types of stress encountered for which special tests can be required to correctly rate the material for brittleness. The method is applicable to films with or without a gelatin backing and to fibre-based or resin-coated (RC) photographic papers. It may also be applied to either raw or processed materials although the brittleness level can be quite different after processing from that before processing.