Engineering controls Devices such as machine guards are usually the first step in preventing hand and finger injuries, particularly those that result from improper use of tools and machinery or careless material handling. Many injuries occur at the point of operation on a machine or tool. Punching and shearing machines like power presses, metal cutters, or shears can crush hands, break bones, and amputate hands and fingers. Rotating shafts like cams, couplings, flywheels, and spindles can catch, mangle, or break fingers. In-running shafts, such as nip points on belts, chains, pulleys, grinders, conveyors, or clutches can catch, mangle, or break hands.
Sanders can scrape the skin.
Pointed objects like screwdrivers, knives, punches, staples, or splinters can puncture the skin. Since we use our hands for virtually everything we do, it's easy to take them for granted. Guards should be installed on any machine where hands could possibly come in contact with the point of operation, or with moving parts. Guard design should ensure that there is no way for hands and fingers to get in from any angle, and that the guards don't create their own pinch points. Guard design also has to permit machine maintenance.