Smoke extraction and ventilation systems necessary for fire indoors. They remove heat and smoke that appear during a fire, reducing air temperature. All mechanisms used for smoke exhaust ventilation must be fire resistant for 1 to 2 hours.
The smoke removal and ventilation system should provide an opportunity for people in the building to leave it through fire escape stairs or in elevators. It is very difficult to accurately calculate the smoke exhaust system, since during a fire there are many factors that cannot be taken into account in advance.
Features of the smoke exhaust system and ventilation
Fire ventilation and smoke exhaust are forced.
The system is a system of channels attached to each other. They are made of non-combustible materials. Smoke exhaust is sometimes carried out by a natural method and is provided by the difference in pressure and temperature on the street and in the room where the fire occurred. The smoke exhaust and ventilation system is also equipped with a mechanism for supplying air to stairwells and fire corridors. The purpose of the smoke exhaust ventilation system is to clean the rooms of smoke and soot in the shortest possible time. Its difference from conventional ventilation systems is that high temperature air mixtures must be blown out intensively without violating the integrity and function of the system. It is necessary to provide a very powerful blowing stream.
If you equip air ducts of thin metal, it warps, the sealing of the channels is broken and smoke spreads to other rooms. To prevent this, the channels are isolated in a special way.
Installation of fire ventilation system
Installation of smoke exhaust ventilation includes the installation of fire dampers and smoke exhaust valves. At the points where fire ventilation is connected to the general system, fire valves are mounted. The damper remains open. As soon as the alarm is triggered, the damper lowers and smoke does not enter the general ventilation duct system. Smoke exhaust valves are installed in the fire ventilation channels. Fire dampers can be square or round, of different diameters, which are selected for the diameter of the ventilation duct.
Installation of smoke exhaust ventilation involves the installation of only special radial fans. They are not affected by hot mixtures of air, smoke and soot. So that smoke does not penetrate the elevator shafts, stairwells, air inlet is organized with the help of air fans.
