Use bridging wires between the distribution box and the galvanized pipe. Requirements for Explosion-Proof Piping Installation The installation of explosion-proof pipelines. To allow individual control of a piping system, a well-designed distribution system is required. Relate normal depth to discharge for uniform flow in open channels. Pre-engineered modular pipe racks are structures designed and built specifically to support multiple pipes where adequate structure is not available. They are mainly used to run petroleum or natural gas pipelines, or cable trays over a river, gorge, highway, or other obstacles.