Basic Knowledge of Fire Doors

Fire doors refer to doors that can meet the requirements of fire stability, integrity, and insulation within a certain period of time.

Overview of fire doors

Types and levels of fire doors:

According to the material, there are mainly steel fire doors, wooden fire doors, steel-wooden fire doors, and other material fire doors. The most commonly seen are steel fire doors which are widely used in construction due to their low cost and good fire performance. Wooden fire doors are more expensive and are generally used in buildings with higher requirements.

In addition, there are stainless steel fire doors, which are generally used in humid environments such as kitchens, and glass fire doors, which are used in areas with high transparency requirements.

According to the number of door leaves, fire doors can be divided into single leaf, double leaf, and multiple leaf fire doors.

According to the fire resistance performance, fire doors can be classified into insulation fire doors (Class A), partially insulation fire doors (Class B), and non-insulation fire doors (Class C). The fire doors commonly used in buildings are Class A fire doors. According to the fire and insulation performance, Class A fire doors can be further divided into Class A, Class B, and Class C fire doors.

Application areas of fire doors

Fire doors are mainly installed in firewalls, important equipment rooms and special functional rooms, evacuation stairwells, conduits, and other locations where openings must be made. For example, the opening on the firewall of two fire compartments must be a Class A fire door.

Equipment room doors such as those in substations, fire pump rooms, elevator machine rooms, generator rooms, oil storage rooms, fire control rooms, firefighting equipment rooms, and ventilation space regulating machine rooms must be fire doors. It should be noted that equipment rooms located in civil defense areas must be equipped with Class A fire doors.

Vertical shafts such as cable shafts, pipeline shafts, smoke exhaust ducts, exhaust ducts, and garbage chutes should be equipped with Class B or Class C fire doors.

Composition of fire doors

A standard fire door consists of the following parts: door frame, door leaf skeleton, fire-resistant filling material, fire-resistant hinge, fire-resistant lock (push-bar lock), expansion seal strip, door closer, sequencing device, electromagnetic door holder, and fire-resistant glass.

The frame and door leaf skeleton of steel fire doors are made of galvanized steel sheet by stamping and assembling. The thickness of the steel plate of the door frame should be greater than 1.2mm, and the door leaf should be greater than 0.8mm. The physical and chemical properties of the steel plate should meet the corresponding standard requirements of cold-rolled and hot-rolled steel plates.

The wooden fire door should use wood that has been treated with flame retardant and meets the requirements of GB/T8625-2005.

The filling material can use alumina-silicate fiber, rock wool, or perlite fire board. Alumina-silicate fiber and rock wool have serious health hazards due to dust pollution and will gradually be eliminated with the implementation of new standards.

In recent years, perlite fire board has been widely used as the filling material for the door core. Perlite fire board has the characteristics of non-toxicity, good insulation performance, and simple process compared with other door core materials. The filling material mainly focuses on its combustion performance and smoke toxicity.