Fire Safety Science Digital Archive

The contribution from different types of building panels to the total fire resistance of a construction has been determined experimentally by testing in furnaces of three different sizes. The agreement between a full size furnace according to IS0 834 and a small size furnace is good, while a medium size furnace gives a somewhat higher fire resistance. The panel thickness is the most important factor and has an almost linear relationship with the fire resistance, common for all wood-based boards and also including gypsum boards. Other factors as panel density, moisture content, type of adhesive and structural composition of the panel will also affect the contribution to the fire resistance. The behavior of various wood-based panels may therefore be slightly different. The fire penetration rate as determined from the measurements in a furnace exposure according to IS0 834 is slower than 0.9 mm/min for all boards with density over 400 kg/m3. The insulation criterion is usually determining the fire resistance, while the panel integrity remains a little longer. This is especially true for inorganic boards which may have a considerably longer time until the integrity criterion fails, while the insulation criterion gives a fire resistance of the same order of magnitude as wood-based boards. The influence of some design factors as mineral insulation, studs and double layers of paneling has also been studied, as well as varying thermal exposure.