221330: Steam and Air-Conditioning Supply

236220: Commercial and Institutional Building Construction

237130: Power and Communication Line and Related Structures Construction

238110: Poured Concrete Foundation and Structure Contractors

238190: Other Foundation, Structure, and Building Exterior Contractors

238210: Electrical Contractors and Other Wiring Installation Contractors

238220: Plumbing, Heating, and Air Conditioning Contractors

238290: Other Building Equipment Contractors

238330: Flooring Contractors

238340: Tile and Terrazzo Contractors

238390: Other Building Finishing Contractors

238990: All Other Specialty Trade Contractors

333411: Air Purification Equipment Manufacturing

333412: Industrial and Commercial Fan and Blower Manufacturing

333414: Heating Equipment (except Warm Air Furnaces) Manufacturing

333415: Air-Conditioning and Warm Air Heating Equipment and Commercial and Industrial Refrigeration Manufacturing

333911: Pump and Pumping Equipment Manufacturing

333912: Air and Gas Compressor Manufacturing

423720: Plumbing and Heating Equipment and Supplies (Hydronics) Merchant Wholesalers

423730: Warm Air Heating and Air Conditioning Equipment and Supplies Merchant Wholesalers

423740: Refrigeration Equipment and Supplies Wholesalers

561210: Facilities Support Services

811310: Commercial and Industrial Machinery and Equipment (except Automotive and Electronic) Repair and Maintenance