Empirical Formulae for Fire demand

 

Empirical Formulae for Fire demand

Following are the various formulae for estimating fire demand :

• Buston's Formula
• Kuichling's Formula
• Freeman's Formula
• National Board of Fire Underwriter's Formula

1. Buston's Formula:

                         Q = 5663√ P

where,     Q = Quantity of water in litres per min.

                P = Population in thousand.

                                                   

2. Kuichling's Formula:

                        Q = 3182√ P

where,     Q = Quantity of water in litres per min.

                P = Population in thousand.

3. Freeman's Formula:

                        Q = 1136(P/10 + 10)

where,     Q = Quantity of water in litres per min.

                P = Population in thousand.

4. National Board of Fire Underwriter's Formula:

• Central congested high valued city -

            For P ≤ 2 lakhs:

                Q = 4637√ P(1- 0.01√ P)

where,     Q = Quantity of water in litres per min.

                P = Population in thousand.

            For P > 2 lakhs:

                Q = 54600 litres/min (for 2 lakhs population) + 9100 to 36400 litres/min for a second fire

• Residential cities -

            Small or low building: 

                    Q = 2200 litres/min

            Larger or higher buildings: 

                    Q = 4500 litres/min

            High value residences, apartments, tenements:

                    Q = 7650 - 13500 litres/min

            Three storeyed buildings in density build up sections:

                    Q = 27000 litres/min.