How does PVC-U perform in a fire?
There are plenty of reasons why PVC-U has added value to the construction industry, but most individuals do not realise that it is much less likely to burn than wood or paint. The action of PVC-U in fires is well understood and reported by scientific authorities.
According to a document produced by the British Plastics Federation:
“PVC-U has other distinct advantages in the event of a fire. “The development of a fire occurs in three distinct phases: ignition; flame spread; general blaze. The avoidance of ignition is the primary requirement in fire prevention, followed by the inhibition of flame spread.
Halogenated flame retardants can improve the fire resistance of materials. Since 57% of PVC-U is chlorine, it is an intrinsically self-extinguishing polymer. This is one of the reasons why it has been widely used in conveyor belts for mining – where the risk of ignition must be avoided.”
Interestingly, “Because rigid PVC-U cannot continue to burn without continuously applied heat from an external source, it cannot contribute to the spread of a fire.”
It is comforting to know that although all organic materials used in buildings including PVC-U will eventually burn in the event of a fire, PVC-U products are self-extinguishing and will stop burning when the ignition source is withdrawn.