Fire doors are designed to prevent the spread of fire and smoke within a building, providing a crucial safety feature in case of a fire emergency. The "FD" rating on an oak fire door refers to the fire resistance level, and it is usually followed by a number such as FD30 or FD60. The numbers indicate the amount of time the door can resist the spread of fire: FD30: This rating means that the door can resist the spread of fire for up to 30 minutes. FD60: This rating means that the door can resist the spread of fire for up to 60 minutes. Fire doors are constructed using fire-resistant materials and are equipped with intumescent strips around the edges, which expand when exposed to heat, creating a seal to prevent smoke and flames from passing through gaps between the door and the frame. In commercial buildings and residential properties, fire doors are often required by building regulations and fire safety codes, especially in areas where fire compartmentation is necessary, such as stairwells, corridors, and fire exits. When purchasing a fire door, it is essential to ensure that it has been properly tested and certified by reputable organizations to meet the necessary fire safety standards. Installing and maintaining fire doors correctly is crucial for ensuring their effectiveness in a fire emergency.