14 Tractor Safety Guidelines E. Machine Hazards Farm machinery produces power, which creates a number of hazards for both operators and bystanders. General machinery hazards include thrown objects, pinch, crush, wrap and shear points. Injuries can be serious, including amputations or death! It is important to recognize and be alert for machinery hazards and take precautions to avoid injury. Pinch Points Belt drives, chain drives, gear drives, and feed rolls are all pinch points. When guards cannot be provided, operators must avoid contact with hands or clothing in pinch point areas. Thrown Objects Any object that can become airborne because of moving parts is a thrown object. Some examples of equipment and implements that can throw objects include mowers, stalk cutters, and combines. Pull-In Points Pull-in points occur where objects are pulled into equipment, usually by some type of processing. Examples include feed rolls, grinders, and forage harvesters. Never attempt to hand-feed materials into moving feed rollers. Wrap Points Wrap points include rotating power take off (PTO) and other shafts (e.g., joints, couplings, shaft ends and crank shafts). Avoid contact with components on rotating shafts, such as couplers, universal joints, keys, keyways, pins, or other fastening devices. Splined, square, and hexagonal shafts are usually more dangerous than round shafts because the edges tend to grab fingers or clothing more easily than a round shaft. However, round shafts may not be smooth and can also grab quickly. Crush Points Crush points are created when two objects move toward each other or one object moves toward a stationary object. Examples include pivot points, such as articulated steering on four-wheel drive tractors, working under raised heavy objects like combine heads, hitches, telescoping shafts, hoods, and doors.