Calorific value is the basis for A1/A2 Euroclasses
ROCKWOOL stonewool withstands temperatures of more than 1000°C. The amount of organic binder is low enough to meet the best Reaction to Fire Euroclass A1. The calorific value or PCS* is less than 1.5 MJ/kg which is far below the limit value of 2 MJ/kg for Euroclass A1.
ROCKWOOL cored sandwich panels with selected organic adhesives meet the second best classification A2, where the limit calorific value is 3 MJ/kg for the panels and 4MJ/m² for each adhesive and coating layer. The critical part is the surface value of 4MJ/m² for the adhesive and coating layer.
So ROCKWOOL cores are the natural first choice if you require robust fire protection performance and, quite simply, if your business cannot afford the risk of a fire and fire spread.
The calorific value of building products is an important criteria for fire risk assessments. The bigger the quantity of organic materials in building products, the larger the amount of organic gases that may develop during a fire. Organic gases are really dangerous because they move much faster than organic liquids or melting materials. A huge concentration of hot organic gases together with an ignition temperature of more than 400°C causes flashover (a fire explosion of hot gases that exacerbates rapid fire spread as it can occur away from the primary fire source).