The water required for unexpected fire accidents and undesirable situations with fire is already designed during the water demand planning system. The demand is calculated based on empirical formulas. For all the formulas given below, Q is the discharge calculated in litres per minute and P is the population measured in thousands.
1. Kuichling’s Formula
Q = 3182P1/2
2. Buston’s Formula
Q = 5663P1/2
3. Freeman’s Formula
Q = 1136[0.2P + 10]
4. National Board of Underwater Formula
Q = 4637P1/2[1 – 0.01P1/2]