Preservation of life and health is the primary task of each and every one. The threat of a fire has a potential nature: short circuit, lightning, human factor … It is necessary to create the safest conditions that will minimize the consequences of a possible disaster. Fire doors are one of the most effective methods of protection.
Fire doors: basic requirements for structures
In accordance with modern regulations aimed at creating and maintaining fire safety conditions, doors of a special design are installed in some buildings and structures. This applies to premises where the level of fires is quite high. These include:
- technical rooms located in basements and basements;
- evacuation exits;
- halls and elevator shafts, the doors of which open onto the staircase;
- exits to the attic from floor areas.
In cases where a residential area is connected to a non-residential one, the installation of fire doors is also necessary. Requirements for the individual placement of doors:
- fireproof door blocks are installed in the corridors, between workshops and warehouses, on the way to the resting places of workers;
- staircases are equipped with similar doors to enable quick evacuation of people;
- fire doors are used as interior doors in places where a large amount of paper documentation is stored;
- rooms with working electrical equipment (switchboard, computer and server rooms) are also separated by fire doors.
When executing design documentation for the construction of a building or structure, the type of doors to be installed must be indicated.
Fire doors types: design features, material of manufacture
Fire doors are classified according to two criteria:
- by material of manufacture;
- by structural features.
As for the materials used for their production, structures are distinguished:
- metal door blocks;
- glass blind or with inserts;
- wooden fire doors.
Important! In the manufacture of glass fire doors, it is not allowed to use reinforced glass and triplex.
The classification in terms of design features is the same as for conventional doors:
- swing – are divided into single-floor and double-floor;
Glass options are either made entirely of one material, or have inserts. Fireproof single-door metal, wood, glass doors are produced. Similar materials are used in the manufacture of double doors. With regard to double-floor structures, the swing parts can be the same or different in width.
Another indicator underlying the classification of fire doors is the degree of fire resistance. Fire resistance – the level of temporary duration of the preservation of the functionality of products under the influence of fire. In total, there are 3 types of structures:
- 1st type. Fire resistance is maintained for 90 minutes;
- 2nd type. Fire resistance is maintained for 60 minutes;
- 3rd type. Fire resistance is maintained for 30 minutes.
In residential premises, doors of the 3rd type are usually installed. In institutions – type 2. For doors of the 1st type, metal is used not thinner than 1 mm. Structures are installed in industrial and other premises with an increased level of fire hazard.
Test method for fire resistance of doors
The essence of the method is to track the time from the beginning of the fire impact on the door block until the appearance of one of the signs that make up the fire resistance thresholds – limit states, for example:
- loss of integrity, expressed in the appearance of a stable flame on the sample for 10 seconds. and more, in the appearance of a flame or smoldering of a cotton pad as a result of penetration of fire or combustible gases through the cracks, in the presence of through holes in the tested door block;
- loss of thermal insulation ability. A temperature of 140 ° C and higher is recorded on the surface of the prototype.
As equipment for research, a furnace is used, smoke channels that provide the required pressure in the firing part of the furnace, as well as measuring instruments that record temperature parameters. The oven during testing has a thermal effect on one side of the sample door.
Steel fire doors, product classification
This section focuses on internal steel structures. They are installed both in industrial and civil buildings and have locking devices.
1. Place of installation. It can be both entrance and interior options.
2. Design features. The door block is equipped with a closed or U-shaped box. The complete set can be supplemented with a threshold.
3. Direction of opening: inward or outward.
4. Finishing method. There are several of them:
- standard or powder paint. The first reduces the cost of the structure, the second provides a durable coating, but the price rises at the same time;
- natural or artificial upholstery: leatherette, eco-leather, tiled trim;
- glass and mirror covers;
5. Mechanical characteristics and features of the security system of fire doors:
- standard doors. Locks of the third class (not lower) and anti-removable pins are installed on them;
- reinforced door blocks. Locks not lower than the second level with a large number of crossbars, reinforced hinges;
- protective blocks. Identical to reinforced, but the lock is installed first class.
Important! The manufacturer is obliged to provide a quality certificate for the material used for finishing.
The main requirement for steel doors is the use for the manufacture of sheets and bent profiles. Welding should be used for the connection. Other methods are allowed, but they should be superior in strength to welding methods.
Metal fire doors
Metal fire doors are the most demanded designs. They are installed in the premises of various public buildings: in offices, government agencies, salons, workshops. They perfectly protect basements, garages, warehouses, etc. from fire and smoke.
Door structures characterized by fire resistance of the first type are classified in the middle category. Within an hour, such a door can protect the room from fire and smoke. This option is always equipped with door closers, which enhances the protection necessary to ensure fire safety. Doors of this type can be either blind or contain glass inserts. The door block is installed more often on three hinged hinges, one of which may have a spring that provides self-closing.
Fire doors can withstand high temperatures for half an hour. This is also a significant time to eliminate the fire source. Such door structures are used for interior rooms with access to a common hall or corridor. Among the doors of this type, there are many models with glass inserts. Steel with galvanized and stainless steel coating is used as a material for manufacturing. In addition to their functionality in terms of fire safety, such doors represent decorative value for the interior.
Aluminum fire doors: technical specifications
The above information was mainly related to metal doors made of steel. Aluminum is not popular as a raw material. The reason for the lack of demand is most likely a bias. Aluminum is a soft and light metal, but at the same time has a high level of heat resistance. The existing restrictions on the dimensions of fire doors in accordance for steel structures are completely inapplicable to light aluminum products.
The aluminum fire door includes the following structural elements:
- frame in the form of a box made of aluminum profile;
- canvas, supplemented with thermal insulation material;
- durable glass unit;
- seals to prevent smoke penetration;
- 2nd level locks.
Most often, aluminum fire doors are double-leafed. This design is not only convenient in everyday use, but also provides a clearer path in case of evacuation. Insulation is laid along the edge of the door leaf, which expands when the temperature rises and strengthens the tightness of the structure, preventing smoke from entering the room.
Important! To prevent fire and smoke from entering the room until the door loses its tightness, it is necessary that the profile and other elements holding the canvas have a higher level of fire resistance.
Fireproof wooden doors
Wood is a material subject to rapid combustion. To ignite it, 300 ° C is enough. And if a fire breaks out, the temperature rises to 900 ° C. So is it possible to make a fire door from this material? It is possible, but such door blocks should be characterized by a number of structural and technological features.
The manufacturing process of wooden doors consists of several stages:
- processing of raw materials with special compounds that increase the level of fire resistance;
- assembling a block from processed material;
- applying heat-resistant polymer compounds to the finished structure.
Both wooden single-leaf fire doors and double-leaf doors are subjected to the same impregnation and coating process. The main purpose of the treatment is to prevent the combination of the cellulose present in the wood with oxygen. This reaction is the basis of combustion. The impregnation blocks the penetration of oxygen into the wood.
The frame and panel of wooden fire doors is much more powerful than that of conventional structures. Expanding seals are also used, metal parts (handles, awnings) have a thermal protective layer that reduces the temperature difference between wood and metal in case of fire.