This International Standard specifies a method for the determination of the edgewise compressive strength (ring crush resistance) of paper and paperboard, especially board used in the manufacture of cartons and packing cases. This International Standard applies to all paper and paperboard with a thickness in the range of 280 micrometres to 580 micrometres. It may also be used for paper and board having a thickness less than 280 micrometres but those results are more a reflection of the paper's stiffness than its compressive strength. For paper and board having a thickness exceeding 580 micrometres, it may be impossible to bend them to the circumference without disturbing the structure.