This article documents the benefits of using smooth bore nozzles on 2½-inch handlines. My experience has indicated that many students in the fire service have learned that the 2½-inch handline is not an attack line but rather a “leader or trunk” line used to stretch a 1¾-inch hose beyond its effective reach or to supply two 1¾-inch hoselines with a gated wye. The standard operating procedure (SOP) on how to load the line appeared to be the indoctrinating point: Caution: When considering friction loss in a 2½-inch trunk line supplying two 1¾-inch lines, each flowing 185 gallons per minute (gpm) from a 15⁄16-inch smooth bore tip, 370 gpm is produced. The resultant friction loss can be as much as 30 pounds per square inch (psi)/100 feet in extended stretch operations; pump discharge pressures may be excessive.

How often do firefighters drill on deploying the 2½-inch line in an offensive, aggressive posture as they gain certification? Proficiency in deploying the 2½-inch line is a fireground necessity whether as a leader line (when it fills out a stretch of 1¾-inch hose) or an attack line. Fireground safety relies on this skill set.

The problem may be that we are all a product of our training. The officer tasked with leading his engine company will draw from previous knowledge. But, has any of his curriculum mandated proficiency in 2½-inch line operations? I fear the 2½-inch line is misunderstood because of a lack of motivation to train on it and its infrequent use.

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