What is Fire load/ Fire Load Calculation

Definition of FIRE LOAD:
·        The weight of combustible material per square foot of floor space.

·        The combustible contents or interior finish of a building per unit floor area, often expressed as pounds per square foot or as Btu per square foot.

·        The amount of fuel within a building which has the potential of burning and releasing heat to feed the growth of a fire.

Fire load can be calculated as follows:-
Weight of material in Kg (mass) X Calorific value of the material - Answer in Kj
For example:
1 tonne of propane @ a calorific value of 47.3 x 10 to the power of 3 Kj/Kg
= 1000 x 47.3 x 10 to the power of 3 = 47300 Kj
If you want to relate this to wood equivalent the formula is:-
mass x calorific value divided by the calorific value of wood, for example (with the calculation above):
1000 x 47.3 x 10 to the power of 3 divided by the C of wood (17.6 x 10 to the power of 3)
= 47300000 divided by 17600
= 2.7 tonnes (wood equivalent)

Calculating the Fire Loading of a Compartment
The fire loading of a compartment is a way of establishing the severity of a fire and the measurement (kj) is related to the heat output. As stated by Drysdale (1985) the formula for calculating the fire loading is noted as:

Calorific Value x Mass (or volume)       = Area Fire Loading Kj/m2
Floor Area

Information on the mass of materials should be obtained from a number of sources using different methods, these included: contacting the manufacturer, consulting information currently available at the location and using relevant standards. The classification of the fire load in each area should be shown using the above formula.