37 Building construction, Building restoration, Construction of railroads and subways, streets and motorways, airports and ports, bridges, viaducts and tunnels, dams, hydraulic and hydroelectric projects, namely, water reservoirs, spillways, wells, river diversion tunnels, water pumping stations, water collection tunnels, pressure pipelines, penstocks, sluices, shafts, canals, intake structures, turbines, pumps, generators, power plants, civil buildings, hospitals and industrial construction complexes in the public and private sectors; repairing of railroads and subways, streets and motorways, airports and ports, bridges, viaducts and tunnels, dams, hydraulic and hydroelectric projects, namely, water reservoirs, spillways, wells, river diversion tunnels, water pumping stations, water collection tunnels, pressure pipelines, penstocks, sluices, shafts, canals, intake structures, turbines, pumps, generators and powerplants, civil buildings, hospitals and industrial construction complexes in the public and private sectors; installation services for elevators, lifts, windows, doors, walls, air handling units, generators, appliances and cooling towers, plumbing equipment, lightning systems, electrical systems, fire systems, sanitary fittings, flooring, ceiling systems, roofs in connection with railroads and subways, streets and motorways, airports and ports, bridges, viaducts and tunnels, dams, hydraulic and hydroelectric projects, namely, water reservoirs, spillways, wells, river diversion tunnels, water pumping stations, water collection tunnels, pressure pipelines, penstocks, sluices, shafts, canals, intake structures, turbines, pumps, generators and powerplants, civil buildings, hospitals and industrial construction complexes in the public and private sectors