What does the term "branch interval" refer to in plumbing?

The term "branch interval" in plumbing is specifically defined as the distance along a stack that corresponds to a story height in a building. This measurement is relevant when considering the venting and drainage systems of plumbing, as it helps to ensure that building codes are met regarding the effective design and functioning of these systems.

Understanding this concept is crucial for proper installation and maintenance of plumbing systems, particularly in multi-story buildings, where adequate ventilation and drainage rely on these specified intervals to prevent issues such as backflow or inadequate drainage. Each story height provides a benchmark for when and where branch lines should be connected and vented to maintain efficiency and compliance with plumbing codes.

Other options do not align with the definition of branch interval; for instance, the vertical section of a water heater pertains to a completely different aspect of plumbing, and the time taken to flush a toilet or the diameter of a pipe does not relate directly to branch intervals and their role in stack and drainage configurations.