Fire pumps are the heart of any fixed fire protection system. Whether installed in commercial buildings, industrial plants, or critical infrastructure, these pumps must deliver water at the correct pressure and flow rate during emergencies. Two terms often encountered when selecting or sizing a fire pump are design flow and rated flow. While they sound similar, they serve different roles in system planning and compliance. Understanding their distinction is key to ensuring your fire protection system is both effective and NFPA 20 compliant.
In this article, we’ll clarify the difference between design flow and rated flow, how each is used, and what implications they carry in real-world applications.
