This major category includes occupations concerned with fabricating, erecting, installing, paving, painting, and repairing structures and structural parts, such as bridges, buildings, roads, motor vehicle body and frame members, cables, girders, plates, and frames. The worker's relationship to hand tools and power tools is more important than that to stationary machines, which are also used. This category also includes semi or nonskilled occupations related to the above, as well as other occupations involved primarily in manual labor.

This subcategory includes occupations concerned with transporting people or cargo over highways, streets, within compounds of construction or institutional areas, on waterways, or in the air.

This subcategory includes occupations concerned with generation, transmission, and distribution of electricity; generation and distribution of steam for heat and power, including marine propulsion; generation of utility gas, and storage and distribution of natural and manufactured gas for power, illumination, or heating purposes; filtration, purification, and distribution of water for domestic, commercial, or industrial consumption; and collection, treatment, and disposal of sewage.