Safety / Protective footwear should give safety to the toe of the user under compression load and to the sole against nail penetration. Compression resistance is determined by subjecting the footwear to a specified compression load and measuring the clearance with the help of a modelling clay cylinder. Nail penetration resistance is measured by measuring the maximum force required for a nail to penetrate through the sole. Requirements and Test Methods for Safety, Protective, And Occupational Footwear for Professional Use Clause 5.4: Determination of Compression Resistance Clause 5.6: Determination of penetration Resistance.