When determining the minimum flow rate for a fire sprinkler system, the available water supply should be based on what?

The minimum flow rate for a fire sprinkler system is primarily determined by the minimum pressure control setting for the pump. This is because the performance of the fire sprinkler system relies significantly on the pressure generated by the pump to ensure that water is distributed effectively to the sprinkler heads. A pump set to a specific minimum pressure control can provide consistent and reliable flow rates necessary to combat a fire, ensuring that the system operates as intended during emergencies.

While factors like the tank's capacity, the size of the pipes, and the dwelling's overall water usage are important considerations in the design of a comprehensive plumbing system, they do not specifically dictate the minimum flow rate necessary for the effective operation of a fire sprinkler system. The pump's pressure control setting directly relates to the system's capacity to deliver water at the required flow rate to suppress fires.