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 skilled occupations concerned with fabricating, erecting, installing, painting, and repairing structures or structural parts. These occupations require recognized levels of competency often attained via apprenticeship.

This subcategory includes semi- or nonskilled occupations concerned with installing, painting, and repairing structures or structural parts or performing a variety of manual labor tasks, and which do not require attainment of competency as do the skilled occupations; i.e., apprenticeship. Other occupations in this subcategory involve the collecting and disposing of refuse.