It may seem difficult to move mountains, but material moving machine operators do it all the time, one load of dirt at a time. Heavy goods are moved around construction sites, warehouses, ships, and mines using machinery. Material moving machine operators employ a wide range of equipment in a variety of contexts. The majority of these workers operate forklifts to move materials around warehouses, storage yards, or construction sites. They may employ conveyor belts to pick up products and transport it to and from enormous warehouses, construction sites, and automobiles. Many operators work for mining corporations that dig mines to recover coal, ore, and other commodities. They put material into shuttles or conveyors that travel from mine to surface. Some companies employ platforms and cages that transport personnel and supplies to elevated construction sites or lower them into mines and quarries. In the construction industry, these machine operators use excavators to clear room for buildings and cranes to load and unload building materials. Cranes are also employed to transport cargo at ports and in iron and steel plants. Dredge operators clear vast amounts of sand and gravel from the bottoms of rivers, lakes, and other bodies of water, allowing ships and boats to move freely. In this industry, safe equipment operation is a primary priority; injury and illness rates are greater than in most occupations. As needed, workers wear gloves, hardhats, or respirators. Most material moving machine operators work full-time, with occasional overnight shifts and frequent overtime. Although there are no formal education requirements for most occupations, a high school education is commonly desirable for crane operators, excavation machine operators, and dredge operators, and some states and towns require crane operators to be licenced.