Which of the following best describes gas piping?

Gas piping is best described as a system that is composed of pipes, valves, and fittings specifically designed to convey fuel gas. This terminology encompasses the essential components that work together to transport gas safely and efficiently from the supply source to appliances or fixtures that use the gas.

In residential and commercial applications, the gas piping system must be constructed of materials that are suitable for gas transfer, such as black iron, copper, or PVC for specific uses, which may include various fittings and valves to control flow and ensure safety. This distinction highlights the importance of each element within the system and its role in delivering gas safely to end-use locations.

The other descriptions do not adequately capture the comprehensive nature of gas piping. For example, characterizing it as a temporary installation does not hold true, as gas piping is typically a permanent feature of buildings designed for long-term use. While some installations may utilize flexible materials, the statement that it is made only of non-flexible materials overlooks the existence of flexible connectors used in certain applications. Lastly, suggesting that gas piping is only used in commercial settings ignores the widespread use of gas piping in residential environments, where it is just as critical for the functioning of home appliances.