Today, fires develop 5 to 10 times faster than they did in the 1950s. The performance of a building during fire therefore has a major influence on the safety of building occupants and first-responders.
Combustible materials can contribute to the spread of a fire and can produce toxic smoke, causing enormous risks for people inside a building.
Combustible materials and smoke formation
Toxic smoke inhalation causes more fire-related deaths than the fires themselves. All combustible materials produce some amount of toxic smoke when they burn. How much toxic smoke will be emitted depends on the material, the amount of oxygen available and how long it burns.
In the early stages of a fire before flashover, smoke will come from the first items ignited, often furniture and other contents of the room. As the fire grows and hits the flashover point, the volume and toxicity of the smoke it produces increases greatly.
The fire then continues to consume the room contents as well as combustible building materials. This includes the building exterior if the fire breaks through windows. This feeds the fire further and expands the amount of toxic smoke. Fire and smoke spreading through the building and up the facade will threaten occupants even if they are not near the starting point of the fire.
How does Rockpanel facade cladding perform during a fire?
The core material of Rockpanel boards is basalt, a volcanic rock that does not burn. It melts only at extremely high temperatures (1.000 degrees Celsius and higher). Rockpanel facade boards therefore have only very low amount of calorific content. This calorific content comes from the small amount of binder which will decompose in case of fire. But it will not burn thanks to the stone wool fibre in the panels. The low calorific value implicates that the panels have a very limited contribution to a fire.