It took longer to research the local plumbing codes and plan the installation than it did to run a new natural gas line to the standby generator I am installing. Code requires an external shutoff valve, a flexible pipe coupling to the generator (to isolate vibration), a 3″ sediment trap, and black steel pipe for all plumbing. Planning involved sizing the pipes and valves to carry the required volume of natural gas and routing the pipe from the existing system to the new location using nothing but commercially available pre-cut lengths of pipe (avoiding the need for renting a pipe threader or obtaining custom cut lengths of pipes). Natural gas pipe fittings leave no room for error. The slightest leak can lead to a house leveling explosion. Every joint must be tested. I used two methods to be absolutely certain of my work. The first method involves applying the equivalent of soapy water to each joint and inspecting for bubbles. The second involves over pressurizing the line with compressed air and checking the next day to ensure that the pressure has not dropped.