In simple terms fire loading is a measurement used by fire-fighters and other fire safety professionals to determine the potential severity of a fire in a given space. It describes the amount of combustible material in a building or confined space and the amount of heat this can generate. The more flammable materials there are present in a space, the higher the fire load and therefore the faster a fire will spread, increasing the potential impact of the fire.
A bare room with no furnishings or items present and concrete walls will have a fire loading of nearly zero. The problem occurs when people bring combustible materials into a space, as this increases the fire loading. However these materials are often essential for the useful functioning of the building, so you can’t completely eliminate fire loading in a building, although you can take steps to reduce it.
Reducing Fire Loading
Some specific uses of a building may carry a high fire load than others however. For example, art galleries tend to have paints, solvents and wooden picture frames present, so therefore the fire load is higher. Storing combustibles separately, with space left in between is advisable and even though it may not be the most efficient use of space, it can dramatically help limit the spread of fire. Also thinking about the types of materials that you are storing in a building and considering the possibility of moving them elsewhere is a good idea.
Calculate the Fire Loading of your building
If you want to delve further into the way that fire loading is calculated, this will show you why certain materials contribute more to the fire loading. To calculate the fire loading of a building, multiply the number of flammable materials in a room by the BTUs they generate per pound. You then divide this by the number of square feet in the room to get the fire loading.
BTU stands for British Thermal Unit and is a unit of heat equal to the amount of heat required to raise one pound of water one degree Fahrenheit at normal atmospheric pressure. Different materials have different BTU ratings per pound for example burning paper produces 6,500 BTUs/lb whereas burning petrol produces 19,000 BTUs/lb. As you can see, having petrol present in a building will greatly increase the fire load of a building, so if you want to reduce the fire loading of a particular building, it can help to find out the BTU ratings of the materials you have present and take steps to remove or carefully plan their safe storage.
Fire Loading and Flashover
One of the reasons why calculating the amount of heat generated by a particular substance when burning is so important, is that the build-up of heat in a fire can trigger deadly flashovers – that can engulf a room in seconds. Flashover occurs when organic materials are heated and undergo thermal decomposition. They then give off flammable gases which lead to simultaneous ignition of the combustible materials in a room.
Call the Professionals
When dealing with fire safety, it’s important to consult the opinion of a fire protection specialist. If you’d like more information on fire loading and how to reduce it in your premises, please get in touch with us today for our expert fire protection advice.Tags: BTUs, calculate severity of fire, fire loading, fire safety, flashover, minimise fire load