Whether the metal structure is at an oil/gas/petrochemical facility with attendant hazardous environment or a mission-critical military installation, electronics, and personnel considerations demand overall direct and indirect lightning protection. A metal structure needs this protection, even though many metal structures are often generally viewed as a “Faraday cage” and supposedly therefore immune from lightning. The reality is that there are many avenues for direct, indirect, and induced paths for lightning energy to get into metal structures. In addition, lightning system codes do not allow the use of metal less than 3/16-inch in thickness as a component of an LPS.
Many metal structures are therefore non-compliant to code without additional LPS components. ALLTEC, Canton, N.C., is a consulting engineer and product solutions provider for many such applications, including mobile military shelter programs. We will discuss the external solution as the most visible and unique portion of the lightning protection three-tier system solution designed for the client.