1. If the particle size of the animal by-products to be rendered is more than 150 millimetres, the animal by-products shall be reduced in size using equipment specified in the approval, set so that the particle size after reduction is no greater than 150 millimetres or such smaller size as the approval shall specify. The effectiveness of the equipment shall be checked daily and its condition recorded. If checks disclose the existence of particles larger than is permitted in the approval, the process shall be stopped and repairs made before the process is resumed.