NFPA 1911 pump capacity test checks pump performance at various pressures. What percent of rated flow is required at 200 psi?

• A. 70%
• B. 100%
• C. 50%
• D. 25%

Answer: (A)

NFPA 1911 uses a pump capacity test to verify that as discharge pressure increases, the pump still delivers a substantial portion of its rated flow. The 200 psi test pressure represents a high-friction, high-pressure scenario you’d encounter in real fires, so the standard requires the pump to maintain at least 70% of its rated flow at that pressure. This ensures the pump has enough capacity under common operating conditions (hose friction, nozzle pressures, elevation losses) without requiring perfect performance. If the flow falls below 70% at 200 psi, the pump would be considered not capable of meeting the standard and would need maintenance or service. For perspective, a pump rated at 1500 gpm should deliver at least about 1050 gpm at 200 psi. The other percentages would either be unrealistically high or indicate poor performance; 70% is the threshold that NFPA 1911 uses to balance realistic pump behavior with adequate firefighting capability.