The fire resistance time of Class B fire door shall not be less than 1.0 hours, and the hardware fittings used on the fire door must also be fire-resistant hardware fittings. Usually, the fire door of this grade is generally used for the entrance door of family decoration.

ZHTdoors yong’inga qarshi eshiklar, yong’in eshiklari va derazalarida 31 yillik ishlab chiqarish tajribasi. Asosiy UL yong’in eshiklari, EN yong’in eshiklari, BS EN yong’in eshiklari va boshqalar.