This part of ISO 16532 specifies a method for the determination of the grease resistance of paper and board. The paper or board can be tested creased or uncreased. The test is primarily intended to establish a level of grease resistance by determining the time taken for a simulated “fat material” (palm kernel oil) to penetrate (break-through) the sheet for papers such as food board, and greaseproof and vegetable parchment. It is also applicable to paper and board which have been internally or surface sized with organophobic materials, or made grease resistant by a plastic extrusion coating.