A water closet in a retail establishment has a fixture unit rating of ________________.

In plumbing design, the fixture unit rating provides a way to quantify the demand a plumbing fixture places on the system. For a water closet, commonly used in retail establishments, the typical fixture unit rating is established based on its expected usage frequency and the volume of water it uses.

A rating of 4 fixture units for standard water closets aligns with the Omaha Plumbing Code, reflecting that this type of fixture generally sees a moderate to high volume of use in a retail environment. This means that while it may not be used as frequently as fixtures in higher-traffic commercial spaces, it still has more considerable demand than a fixture with a lower rating.

The code specifies that when planning the plumbing system, it's essential to consider these fixture unit ratings to ensure the system can handle the expected loads, significantly impacting the sizing of pipes and other plumbing components. Hence, the rating of 4 effectively addresses the expected use without overestimating the demand, which can lead to unnecessary larger piping and system components.