... not the alkene burns materials. It has the fire-resistant ability with over 1000 degrees Centigrade, the panel ... and wallboards limit of fire-resistant is 120 minutes for 100mm thick (REL), 60 ... ), 30 minutes for 50mm thick(REL). The fire-resistant grade for 50-70-100mm thick panel is ... 0/1 grade (Its fire-resistant grade is divided into 0 , 1 , 2 , ...