Most passive fire protection products are ‘fire resisting’. Fire resistance is the ability of elements of construction such as beams/columns, walls, floors and doors etc. to ‘resist fire’ for certain periods of time. A component with a fire resisting function operates in one or more of three ways:
- It resists structural collapse
- It resists the passage of smoke and hot gases (integrity)
- It resists heat conduction (insulation).
A structural floor in a multi-storey building will require all three. A non-loadbearing compartment wall will have to provide insulation and integrity. A steel beam or column will only have to provide structural stability.
Loadbearing elements such as beams, columns, walls and floors have to be able to support their load under fire conditions. Separating elements such as doors, walls, glazed screens and suspended ceilings have to stop fire passing through them either as flames or by heat conduction. Loadbearing and separating elements such as loadbearing walls and floors have to do both.
Any building services that pass through separating elements such as cables, pipes or fire resisting ducts need to be fire stopped to ensure that the service does not provide an easy route for fire. These are critically important since they are often located in concealed spaces, which means that fire can pass unnoticed. It is vital that all protection measures are correctly designed, specified and installed if the building is to behave as expected should fire break out.