Fire is one of the most important “enemies” of man: it easily destroys buildings, houses, various structures, crops.
Flaring fires occur less and less every year – and this is due not only to human accuracy, but also to the use of modern special-purpose devices – fire extinguishing installations.
Conventionally, the currently used systems can be divided into 2 types:
Sprinklers are recommended for use in rooms where a lot of heat is expected during a fire. They are designed to fight localized fires or to cool structural elements. Deluge installations are used on large areas and for setting up water curtains.
The sprinkler fire extinguishing system got its name from the English sprinkler – sprinkler, sprinkler. This fire extinguishing system differs from deluge systems in that water is constantly in them, and the spray head (in fact, the sprinkler) is equipped with a heat lock or closed with a heat-sensitive flask.
When the temperature rises to the programmed level, the lock is unsoldered (the bulb bursts), and the extinguishing liquid begins to irrigate the fire. There are also fine spray systems.
Deluge installations have their own characteristics. Their purpose is to extinguish the source of fire and prevent the further spread of the flame. The “role” of the irrigating part in this case is performed by a drencher (from drench – which in English means “irrigate”) – an open-type head. Its inclusion in work does not come from a thermal lock (like in sprinkler installations) – in this case it is simply absent.
The signal to start the equipment comes either from a person (by pressing a button) or from a fire safety system (for example, from a smoke detector). In fact, the main difference between these systems lies in the design of the heads.
It should also be added that installations of this category are kept empty, and the extinguishing liquid (it can be either water or foam) begins to be supplied to the network only when a signal is received.
The use of such equipment is usually chosen for premises in which the risk of fire is minimal, or its damage is not capable of quickly causing great damage.
According to the principle of operation, the installation seems to create a wall of water (foam), which both prevents the spread of fire and extinguishes it, and in addition also prevents the spread of harmful substances that can be released during combustion.
Usually, its use is relevant in corridors, above doorways, and also locally – for example, around a possible fire source. However, similar installations are used for other cases – to cover the full area of a possible fire.
About types and categories
Depending on the fire extinguishing agent used, the installations can be as follows:
1. Automatic water fire extinguishing installations – fire extinguishing occurs by means of water injection;
2. Automatic foam fire extinguishing installations – in this case, of course, the fire-fighting agent is a special foam composition;
3. Modular gas fire extinguishing installations – local installations of a smaller size, which can be put into operation (automatically or manually) in certain 4. Sections (as a result – savings are achieved and premises that are not endangered will not be flooded);
5. Powder fire extinguishing installations – equipment in which instead of water and foam, mineral salt with special additives is used to extinguish the fire (depending on the purpose, the composition of the salt may vary).
Powder fire extinguishing design is a rather difficult task. Not every enterprise will deal with the solution of such an issue as the design of fire extinguishing systems. It is also possible to use gas systems when carbon dioxide (CO2) acts as an extinguishing agent. By the way, this method is one of the oldest (it has been practiced for over a hundred years).
The installation of a gas fire extinguishing system is partially different from other systems, since the fire extinguishing agent here is gas (most often carbon dioxide). Fire extinguishing installations of this type are now used extremely rarely, and mainly at specific industrial facilities, so we will not focus on them.
Sprinkler fire-fighting systems are subdivided into:
1. Water-filled – in this case, the system pipeline is filled with extinguishing liquid only;
2.Water-air – in this case, the supply pipeline is filled with water, and the supply and distribution ones can contain either air or water;
3. Air – in this case, the supply and distribution pipelines are always filled with air.
Deluge systems, according to the type of filling of the pipeline, are not divided into categories. However, water-based fire extinguishing systems of this type are classified according to the type of drive:
The design of automatic fire extinguishing installations is the most important stage in the creation of building security systems. In the future, the fire safety of the facility will largely depend on the extent to which all points of the project are consistently and competently implemented. It is clear that it is more expensive to save money on a design firm here.
Designing water fire extinguishing is a complex process, including the creation of detailed documentation. In terms of its importance to safety, it can only be compared with the development of a fire alarm project.
The design of automatic fire extinguishing is carried out in the following stages:
1) A preliminary assessment of the premises requiring protection is carried out.
2) Locations requiring the installation of sprinkler heads are identified.
3) The location of the pump is determined.
4) The “routes” of the line are determined through which water (foam, powder) will flow.
5) The locations of the sensors are determined.
6) The locations of the water intake points are determined.
7) The required pump power, the volume of its reservoir, type (water, foam, powder, deluge or sprinkler) are determined.
Without fail, an agreement will be carried out in the appropriate authority, which must evaluate the drawn up project. To create home fire extinguishing installations, coordination and approval is not required – this is relevant only for industrial buildings.
Installation of water fire extinguishing systems should also be carried out only by specialists. Correctly performed installation of fire extinguishing is a guarantee of timely operation of each element of the system. The water fire extinguishing system is installed in several stages:
1) Selection of fire extinguishing equipment and delivery.
2) Laying of cable routes and water pipelines.
3) Installation of irrigation devices, sensors, the pump itself, control panels.
4) Integration of the system into engineering networks.
5) Commissioning works are in progress.
After these stages, the water fire extinguishing system is ready for testing and acceptance.