The fire prevention time of fire doors is mainly determined by fire boards. In this regard, the performance of fire boards used for Class A fire doors is generally better than that of fire boards used for Class B fire doors, so the overall performance is better than that of Class B fire doors.

ZHTdoors albaabbada dabka, 31 sano oo waayo-aragnimo wax soo saar ah oo albaabbada dabka iyo Daaqadaha. Albaabada dabka UL ee ugu muhiimsan, albaabada dabka EN, BS EN albaabbada dabka, iwm.