NFPA 1410 requires the initial attack line to provide a minimum flow of which value?

• A. 50 gpm
• B. 100 gpm
• C. 200 gpm
• D. 500 gpm

Answer: (B)

The main idea here is that the first line you pull to start suppressing a fire must move a sufficient volume of water to begin cooling, knockdown the fire, and support interior operations. NFPA 1410 sets a minimum flow of 100 gallons per minute for the initial attack line, which is a practical middle ground: high enough to make a real difference in typical early-stage fires, but not so high that it complicates handling or safety in training scenarios. Flows around 50 gpm are generally too low to slow a growing room-and-contents fire effectively, while flows of 200 or 500 gpm are more characteristic of larger-scale streams or special tactics and exceed the minimum needed for an initial attack. In practice, this minimum is often achieved with a common handline setup (like a 1¾-inch line with a suitable nozzle) that can reliably deliver around 100 gpm, aligning training with real-world expectations and safety.