Which of the following is NOT a plumbing fixture?

A washing machine is classified as a home appliance rather than a plumbing fixture. Plumbing fixtures refer specifically to devices that are directly involved in the delivery and disposal of water. These fixtures typically include faucets, sinks, toilets, and water heaters, which are essential components of a plumbing system and designed to be connected to the water supply or drainage systems.

Faucets are fixtures that allow for the regulated flow of water, while water heaters are essential devices that heat water for domestic use. Pipes, although crucial for the transportation of water, do not serve the same functional purpose as fixtures; they are part of the plumbing system infrastructure rather than fixtures that hold or dispense water.

In contrast, a washing machine, while it uses water and is connected to the plumbing system, acts as an appliance that combines washing capability with water use. Thus, it does not meet the criteria to be labeled a plumbing fixture in the context of plumbing terminology.