Fire doors are classified into three grades, A, B, and C according to different fire resistance time periods. Class A fire doors are 1.5 hours, Class B fire doors are 1 hour, and Class C fire doors are 0.5 hours.

metal door units,fire door vs normal door,fire rated door kick plate,metal door with glass insert,metal door hinges,

fire resistant door manufacturer,metal door units,fireproof main door,fire proof door material,metal door hinges,fire rated door thickness,metal door b&q,metal door with glass insert,fire rated door 90 minute,safety metal door design,

wooden fireproof doors,fire rated door with glass,metal door with glass insert,fire rated door ul,fire rated door residential