A valved pipe shall be provided at the lowest point of each tank to permit emptying of the tank. The tank drain pipe shall discharge as required for overflow pipes and shall not be smaller in size than specified in Table 606.5.7.
|TANK CAPACITY (gallons)||DRAIN PIPE (inches)|
|Up to 750||1|
|751 to 1,500||11/2|
|1,501 to 3,000||2|
|3,001 to 5,000||21/2|
|5,000 to 7,500||3|
For SI: 1 inch = 25.4 mm, 1 gallon = 3.785 L.