37 installation of drywall, flooring, and ceilings for all types of commercial, industrial and government construction; installation of environmental control structures, such as "clean rooms"; insulation contracting services, namely services of insulation of mechanical systems (including, for example, pipes, ductwork, precipitators, boilers, turbines, tanks, generators, baghouses, scrubbers, AQCS components and other equipment) for commercial, industrial, power and process, manufacturing and government construction; insulation of such mechanical systems for nuclear, gas, geothermal, electrical and fossil fuel power plants; insulation of such mechanical systems in refineries and chemical process plants; insulation of such mechanical systems for resource recovery and cogeneration facilities; insulating of such mechanical systems in ships; contracting services relating to the construction of cold storage facilities