How are "branch lines" defined within a sprinkler system?

Branch lines within a sprinkler system are specifically defined as the pipes that deliver water from cross-mains to individual sprinklers. This characteristic is fundamental to their role in a fire protection system, as they are responsible for transporting the water to the points of application where the sprinklers are located.

The function of branch lines is crucial because they ensure that each sprinkler head receives enough water to effectively control or extinguish a fire. Understanding this definition supports the overall design and installation of sprinkler systems, as efficient water delivery is essential for system performance.

Other concepts mentioned, such as main supply lines or valves, emphasize different components or functions within the sprinkler system. Main supply lines serve a different role by feeding water to the entire system, while valves control water flow but are not themselves branch lines. Similarly, while auxiliary sprinklers may provide extended coverage, they do not define the term "branch line" as used in NFPA 13.