AITHON A90H achieved four hours fire resistance classification on concrete slabs and walls. At the end of the test, after more than 240 minutes of fire, the char showed a perfect integrity and adhesion to the concrete, despite of the heavy slab bending (18 cmt over a 4 mt span).
The BS EN 13381-3 regards the fire resistance of concrete structures and the performance of the intumescent coatings applied on concrete are expressed in terms of equivalent concrete thickness. The method defines the quantities (in gr/m2) of intumescent coating required to achieve the same insulation performance provided by different thicknesses of concrete. The calculation of the equivalent concrete thickness required for slabs and walls exposed to fire on one side is based on fire test results achieved on loaded slabs having minimum (500 gr/m2) and maximum (2035 gr/m2) applied quantity of intumescent coating. Linear interpolation between minimum and maximum is allowed.
BS EN 13381-3