The standpipe system demand shall include 500 gpm for the first standpipe and ______ gpm for each additional standpipe until the total system demand is simultaneously flowing.

The standpipe system demand shall include 500 gpm for the first standpipe and ______ gpm for each additional standpipe until the total system demand is simultaneously flowing.

• A. 150 gpm
• B. 250 gpm
• C. 350 gpm
• D. 500 gpm

Answer: (B)

Standpipe system demand is built around a fixed amount for the first standpipe and then a smaller, repeated increment for each additional standpipe that could be flowing at the same time. The first standpipe is assumed to need 500 gpm to provide adequate initial attack capability. For every extra standpipe that might be in use simultaneously, an additional 250 gpm is added. So, for two standpipes you’d have 500 + 250 = 750 gpm; for three standpipes, 500 + 2×250 = 1000 gpm, and so on. The 250 gpm increment reflects the sharing of flow between multiple hoses while keeping the overall system pressure and capacity within practical limits.

Standpipe system demand is built around a fixed amount for the first standpipe and then a smaller, repeated increment for each additional standpipe that could be flowing at the same time. The first standpipe is assumed to need 500 gpm to provide adequate initial attack capability. For every extra standpipe that might be in use simultaneously, an additional 250 gpm is added.

So, for two standpipes you’d have 500 + 250 = 750 gpm; for three standpipes, 500 + 2×250 = 1000 gpm, and so on. The 250 gpm increment reflects the sharing of flow between multiple hoses while keeping the overall system pressure and capacity within practical limits.