What does the term 'fixture unit' measure?

The term "fixture unit" is a critical concept in plumbing design that quantifies the demand a plumbing fixture will impose on the plumbing system. It is a way to assess how much water flow and drainage each fixture contributes to the overall plumbing system’s requirements.

By assigning a certain number of fixture units to different types of fixtures (like sinks, toilets, showers), plumbers can evaluate the cumulative load on the plumbing system and ensure that pipes are sized appropriately to handle peak usage without causing issues such as slow drainage or inadequate water supply. This measurement helps in the design and sizing of pipes, fixtures, and other components within a plumbing system, ensuring efficiency and reliability.

In essence, fixture units help in establishing a standard way to represent the impact of various fixtures on the plumbing infrastructure, which is essential for effective plumbing design and functionality.