general building construction services; general civil engineering, namely, basic construction services; bricklaying, tile laying, and block laying services; installation, repair and maintenance of machinery, namely, pumps, freezers/freezing equipment, turbines, boilers, burners, fans, heaters, air-conditioning apparatus, metalworking machines and machine tools, chemical-mechanical polishing machines used in the manufacture of semiconductors; electrical contracting; electrical work, namely, installation and repair of electric appliances, installation and repair of electric distributing wires; telecommunication work, namely, construction, installation, maintenance and repair of telecommunication equipment and systems; repair and maintenance of burners, boilers, pumps, freezers, freezing equipment, computers and computer peripherals, central processing units, programmed data carrying electronic circuits or magnetic disks; maintenance, inspection and management, namely, planning, designing, operating, and repair of boilers; repair and maintenance of plants, namely, machines and apparatus for treating water, sewage water, industrial water, industrial waste water, night soil, refuse, industrial waste, industrial waste gases and heat; installation, repair and maintenance of equipment for supplying water to or draining water from buildings; installation, replacement and cleaning water receptacles or water tanks in elevated positions; repair and maintenance of pumps and fans; installation and cleaning of pumps, boilers, electric power plants, petro-refining plants and petro-chemistry plants and other plants, namely, machines and apparatus for treating water, sewage water, industrial water, industrial waste water, night soil, refuse, industrial waste, industrial waste gases and heat
Building Construction and Repaircustom design of plants, namely, machines and apparatus for treating water, sewage water, industrial water, industrial waste water, night soil, refuse, industrial waste, industrial waste gases and heat; engineering services in the field of environmental hygienic facility systems and water purifying apparatus and water contamination control equipment; engineering services in the field of ultrapure water production systems and various other environmental hygienic systems; engineering services in the field of cogeneration systems and other electric power plants
Computer and Scientific