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NFPA 13

Riser sizing by demand

Suggested riser diameter for a given total demand and velocity limit.

d = √(4·Q / (π·v)). Targets velocity ≤ 6.1 m/s.

Result
Minimum internal diameter
91.4 mm
Next standard size (DN)
DN100

Formula: d = √(4Q / (π·v))

Reference: NFPA 13

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