To use the chart above, simply find the pressure in pounds that your flow figures were tested at in the left hand column. Then follow the line over to the right until you reach the number of gallons per minute under the correct diameter of pipe being used.

All formulas for finding the amount of water that will flow through a pipe in a given time are approximate. The formula used above will give results within 5 to 10% of actual results if applied to pipe lines carefully laid and in a fair condition.