Verify that the installation of cooling and refrigeration systems complies with code requirements, the manufacturer's instructions, and listing of the equipment, and have proper access and clearances, supply air, return air, and connection to ducts and plenums. Verify the proper class of refrigerants used. Verify that refrigeration piping, valves, and controls are installed according to code provisions. Verify size, clearances, access, exits, emergency controls, and signs in refrigeration rooms.