NFPA 13R® is a residential sprinkler design standard focused on low-rise residential occupancies. The Standard's intent is to provide a sprinkler system that aids in the control of residential fires and provides improved protection against injury and life loss in multi-family dwellings. Requirements concern automatic sprinkler system design, installation, and maintenance including component listing, hydrostatic tests, sprinkler temperature ratings, design documentation, aboveground pipe and equipment, underground pipe, pre-engineered systems, water supply sources, multipurpose piping systems, and hydraulic calculations.