Design & SizingQuestion 18 of 110
Using the rational method Q = 0.0104 x A x i, where A is the projected roof area in square feet and i is the rainfall rate in in/hr, what is the design storm flow for a 6,000 ft^2 roof at a 3 in/hr rainfall rate?
a.62 gpm
b.187 gpm
c.124 gpm
d.312 gpm
Explanation
Q = 0.0104 x 6,000 x 3 = 187 gpm. The 0.0104 factor converts one inch per hour of rain over one square foot into gpm. This design flow is then read against the vertical leader and horizontal storm-drain tables to size the conductors.
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