Profile: Approved Lightning Protection Co. Inc. is specialized in providing lightning protection for commercial & industrial buildings. We offer UL Master Label and LPI Certified lightning protection systems, as well as, enhancing lightning protection systems. We also have a complete line of secondary surge protection devices. Air terminals shall be installed for stacks, flues, mechanical equipment, and other objects not located within a zone of protection. Non-metallic objects or metal objects having a metal thickness of less than 3/16'' require the installation of air terminals and required conductors.