A water closet in a retail establishment has a fixture unit rating of how many?

The fixture unit rating for a water closet, commonly referred to as a toilet, in a commercial setting such as a retail establishment is typically assigned a value of 4 fixture units. This rating is derived based on the average demand placed on the plumbing system by the fixture, taking into consideration its usage patterns in non-residential contexts.

In the context of plumbing codes and drainage design, fixture units help in calculating the potential load that the drainage system must handle. The rating of 4 fixture units for a water closet reflects a balance between the expected usage and the peak demand situations that may occur, ensuring that the plumbing system is adequately sized to accommodate multiple fixtures during busy periods.

The other values do not align with the standardized rates often used in plumbing codes for the water closets in retail establishments. Thus, understanding that the correct fixture unit rating of 4 supports the plumbing design and performance is key in managing water consumption and drainage effectively.