One system riser can supply up to how many square feet on a single floor in an ordinary occupancy?

One system riser can supply up to how many square feet on a single floor in an ordinary occupancy?

• A. 24000
• B. 52000
• C. 60000
• D. 72000

Answer: (B)

The main idea is how much floor area a single system riser can feed while keeping adequate water pressure at all sprinklers. A system riser is the vertical feed that brings water up to the sprinklers on a floor, and its capacity is limited by hydraulic calculations: the further a sprinkler is from the riser, the more friction loss there is, so the pressure at the farthest head must still meet the required minimum. For ordinary occupancy, design practices typically limit one riser to about fifty thousand square feet on a single floor. This keeps the pressure at the most distant sprinklers within spec; if the floor area is larger, you’d add another riser or create separate zones to maintain proper coverage and pressure throughout.

The main idea is how much floor area a single system riser can feed while keeping adequate water pressure at all sprinklers. A system riser is the vertical feed that brings water up to the sprinklers on a floor, and its capacity is limited by hydraulic calculations: the further a sprinkler is from the riser, the more friction loss there is, so the pressure at the farthest head must still meet the required minimum. For ordinary occupancy, design practices typically limit one riser to about fifty thousand square feet on a single floor. This keeps the pressure at the most distant sprinklers within spec; if the floor area is larger, you’d add another riser or create separate zones to maintain proper coverage and pressure throughout.