Code 3548 applies to employers engaged in manufacturing various types of machinery such as bookbinding machines, printing presses, collating machines, punchers, stitching machines, cutters and other equipment.  The raw materials consist of steel bar stock, sheet metal frames, iron and aluminum castings, mechanical components, electric motors, chains and chain sprockets which are purchased from others.  Parts are then machined by milling, drilling, tapping and turning.  Additional parts and/or electrical components, electric motors, etc. are then added on with the use of small hand tools.  The parts are then assembled by welding and bolting together to form the machines, which are then painted and dried before shipment.  Lastly, the machines are inspected and tested for proper functioning prior to shipping them to customers.