An example of a smoke removal project. Smoke ventilation project Smoke exhaust system project example explanatory note

Description:

This article provides the basics of smoke control technology with a list of typical preparatory actions for the design of these systems and a list of common design tasks.

Fundamentals of designing smoke exhaust systems

C. E. Magdanz, Project Development Manager, Alvin and Associates, Omaha, Nebraska, USA

Professional firefighters calculate the time for evacuating people from a burning building in seconds. The fire flares up quickly, and the smoke - also a very serious danger - spreads faster than the fire. The natural reaction to a fire is to flee. However, it is difficult to quickly escape from large or high-rise buildings, tunnels, and underground structures. Escape from a fire is impossible for physically helpless people, some hospital patients (critically ill or undergoing surgery), prisoners. For such cases, smoke extraction systems provide the necessary protection.

This article provides the basics of smoke control technology with a list of typical preparatory actions for the design of these systems and a list of common design tasks.

Terminology

The term "" is used here in a broad sense, since this process involves the use of the physical properties of materials and structures, equipment and various methods (singly or in combination with each other) to control the spread of smoke and to remove it. Physical parameters are passive characteristics, such as, for example, the smoke permeability of structures. Equipment - fans, openable windows and smoke detectors. Methods - design solutions, such as room insulation, smoke exhaust aeration, mechanical smoke exhaust system. Insulation of rooms is based on the use of the physical properties of structures designed to prevent the spread of smoke by isolating the source of ignition. The smoke exhaust aeration system uses separate devices, not connected to the duct system, designed to remove smoke due to the natural pressure difference inside and outside the building. A mechanical smoke extraction system uses equipment (fans, ducts, valves, detectors) to control the movement of smoke by creating the necessary pressure differences by mechanical means. The normal operation of mechanical smoke exhaust systems depends on the physical properties of building structures.

Closely related to smoke extraction is the task of firefighting, which uses the physical properties of structures (fire-resistant barriers), equipment (sprinklers) and methods (room insulation). The placement of fire-resistant partitions and sprinkler systems is regulated by various regulatory documents, and these documents do not require mutual agreement. Thus, fire and smoke barriers are often inconsistent with sprinkler system zoning. An example of an object with coordination of fire extinguishing and smoke exhaust systems is a building project with an atrium, in which the signal to turn on the mechanical smoke exhaust system is the flow of water in the pipes of the sprinkler system.

Purpose of smoke exhaust systems

The purpose of smoke exhaust systems is as follows:

Preventing the spread of smoke from an ignition source.

Prevention of smoke ingress on evacuation routes (ensuring acceptable conditions for people evacuating from the building).

Ensuring a microclimate outside the source of fire, allowing the fire extinguishing personnel to work normally.

Protecting people's lives.

Protecting property from damage.

This list does not include the creation of normal conditions in the room where the source of fire is located, nor does it specify the condition that the ways and means of evacuation must be clearly defined and securely separated from other areas of the building.

Development of smoke control systems

The concept of smoke removal is quite ancient. As soon as a man first built a hearth in his dwelling, he immediately realized the need for an opening for the release of smoke.

The modern practice of smoke control dates back to the 1940s, when it became apparent that smoke spreads through the ducts of ventilation systems far beyond the fire. This predetermined the appearance of fire dampers and static smoke protection systems.

Smoke dampers and dynamic smoke extraction systems began to appear in the 1970s when it became clear that shutting off smoke paths in a static smoke control system conflicted with the need to supply fresh air to hospital operating rooms. In operating rooms, supplying clean air to the patient is the first line of defense against infection. When an operation is in progress, it is unacceptable to cut off the supply of clean air, especially when the neighboring rooms are filled with smoke. For this reason, many operating theater air conditioners have been designed to supply 100% outside air (assuming no smoky outside air).

With certain standards in place, equipment manufacturers will be able to specify fan performance at both normal and elevated temperatures in the specifications. This will allow designers to select fans based on their characteristics both in normal operation and in smoke extraction mode.

A useful tool used in the design of smoke extraction systems is computer simulation of aerodynamics. The essence of the numerical modeling method is that the volume of the room is represented as a certain (finite) number of "thin" zones. The ignition source occupies a relatively small number of such zones. A computer is used to solve a set of aerodynamic equations describing the jet stream on a time scale, thus simulating the spread of smoke. The correctness of the simulation was tested in the course of full-scale field studies. The test confirmed the high accuracy of computer modeling, its usefulness and applicability were recognized. However, since computer simulation is quite complex, it requires appropriate qualifications to perform it. The most suitable area for the application of computer models are non-standard buildings of complex configuration.

Research is also carried out in related areas. So, for example, the optimal placement of smoke sensors in rooms and air ducts is determined, the phenomenon of “jumper” is studied when atriums are smoked (when, at a certain placement of exhaust openings, clean air flows through a layer of smoke), the reliability of protection against smoke in staircases by creating excess pressure is studied.

Concerning the prospects for further research, one can point out the problem of maintaining the system's operability. For example, now there is no provision for any protection by means of smoke removal of places where communications are laid. Another problem is the strength and reliability of smoke protection structures (see sidebar “Smoke protection structures”).

Smoke removal methods

Smoke protection and extraction systems can be either static or dynamic. In the presence of smoke in the building, the static method involves stopping all fans, as a result of which the spread of smoke slows down due to the isolation of the premises when air exchange is stopped (the basic method of combating smoke).

In a dynamic system, when smoke occurs, all or certain fans continue to operate in normal or special mode, creating overpressure areas in accordance with the smoke control scenario. Fans in dynamic systems can be separate to remove smoke and supply clean air for pressurization, or both in sequence.

Dynamic smoke extraction systems can be used alone or in combination with smoke barriers. An example of a separate dynamic smoke exhaust system is an air curtain that creates an air flow as a barrier to the spread of smoke. More common are smoke exhaust systems, the effectiveness of which depends on the reliability of smoke protection structures. Examples include an atrium with an exhaust hood (Fig. 1), a pressurized stairwell (see the sidebar “Creating overpressure in stairwells”), pressurizing elevator shafts and shelters, creating overpressure in “sandwich” zones (Fig. 2). In typical sandwich systems, the fire floor is in the exhaust zone, and one or two floors above and one floor below is in the overpressure zone. Zoning smoke exhaust systems with a single supply unit for all zones are very complex. To simplify installation, commissioning and long-term operation, designers must provide a separate ventilation unit for each zone.

All smoke exhaust systems interact with other engineering equipment of the building, with the greatest importance being the power grid and the fire safety system. Since smoke dampers close on a fire signal, it is permitted not to install these dampers in the air ducts of the smoke exhaust system, since this system must work during a fire. However, this exception does not apply to fire dampers, which must be installed in the ducts of the smoke exhaust system at the points of passage through fire-resistant partitions.

At the same time, it should be noted that many elements related to smoke protection are not controlled by the HVAC engineer.

It is very important for the designer of a mechanical smoke extraction system to coordinate with other specialists to make sure that the protective barriers are secure and properly placed, to check the power supply of the equipment, the connection with the fire alarm and the fire extinguishing system. The correct functioning of the gaseous fire extinguishing system can be impaired by the operation of the smoke exhaust system, since the movement of air necessary for smoke removal can lead to a decrease in gas concentration to a level insufficient to extinguish the fire.

Equipment for smoke exhaust systems

Equipment for smoke exhaust systems can be both special and general purpose. Special equipment is used only in the presence of smoke. General purpose equipment is typically used for other HVAC needs and also serves to remove smoke in the event of a fire.

Special smoke extraction equipment, as a rule, is not replaced during the life of the building, it is always operated in the same way, in accordance with its intended purpose. Special equipment is relatively easy to operate as it serves a single purpose. However, such equipment requires a special place and regular maintenance, as its reliability depends on it. Fans for pressurizing stairwells and for extracting smoke from atriums are examples of special equipment.

The frequency of maintenance of general purpose equipment is determined by its daily use; there is no need to take up extra space in the building, because the same equipment is used for different purposes. At the same time, there are a number of disadvantages - the complication of regulation due to multifunctionality, the possibility of accidental damage to the smoke exhaust system during the reconstruction or renovation of HVAC systems. An example of the use of HVAC equipment for smoke exhaust systems is the supply fan of an air conditioner to create excess pressure in zones in a “sandwich” system.

Buildings in which smoke exhaust systems are commonly used are high-rise buildings, prisons, hospitals, covered markets, underground structures, transit tunnels. Premises inside buildings with the need to install these systems - atriums, evacuation stairs, elevator shafts, shelters, theater stages, smoking rooms.

Preparation for design

1. Familiarize yourself with the requirements of regulatory documents and the wishes of the customer, which determine the need for installing smoke exhaust systems. The regulations provide the minimum requirements. Customers sometimes make demands beyond the required minimum, especially when it comes to protecting property.

2. If a smoke extraction system is expected to be required in the facility, check with regulations. (If you think an alternative solution is possible, be prepared to discuss the issue.) Regulations generally allow for different design approaches. Once the need for a smoke exhaust system has been determined, select the appropriate options and options.

3. After choosing the design principle, check it against the normative documents and discuss the procedure for acceptance tests. Sometimes the acceptance test method can influence the choice of design solution.

4. When designing a system, strive for its possible simplification. In the future, the customer will have to maintain it as vital to the building.

5. Remember that system testing and fire drills will be the first load on the system. Consider weather conditions when considering drill scenarios. If the heat exchanger freezes during a real fire, this is not a problem, but during a drill it is unacceptable.

6. Do not forget that the purpose of regulatory documents is to protect people, and the designer has a wider task. The project requires the development of an economical system that meets both customer and regulatory requirements. For the designer, this can be a compromise task.

7. Keep minutes of all discussions and decisions made. Using all project documentation, draw up a diagram of the interaction of the smoke exhaust system with other HVAC systems.

Design issues

Since the placement of fire-resistant partitions has a significant impact on the layout of the ducts, they are placed before drawing up a detailed ventilation scheme. Changing the location of these baffles later can be a very big problem for the designer of the smoke exhaust system. An example is the situation with a "sandwich" system, where a fireproof partition separates rooms on the same floor. Relocation of baffles may entail alteration of the air distribution, especially if a separate supply unit is used for each smoke zone.

The only reliable way to field test a smoke exhaust system is to create a source of hot smoke. Since this is practically impossible, cold smoke is usually used in tests. Thus, the real test of the effectiveness of the smoke extraction system is delayed until the event of a fire, which, fortunately, is rare. And because of the rare opportunity for field testing, the improvement in smoke extraction systems, backed by strong arguments in favor of new technology, lags behind HVAC systems for everyday use (heating and cooling).

Since the design principles for smoke exhaust systems vary and the opportunity to actually test them is infrequent, educating standards officials, planners, architects and building owners in this area is a major challenge that is not easy to accomplish. And since HVAC engineers are the leading developers of smoke exhaust systems, they should also become leaders in the process of training other specialists.

Smoke-tight structures

The integrity of smoke-tight structures may not be ensured in the following difficult situations:

1. Building codes often do not explicitly state when smoke-tight ceilings (smoke barriers) must be installed. There are only indirect indications of this - the requirement to install smoke dampers.

2. If there is an indication in the regulations for the installation of smoke barriers, this most often coincides with the requirement for the installation of fire-resistant partitions (fire barriers). However, the developmental production of flame retardant devices with independent test labs usually provides certification for fire resistance and temperature only. Even if one of the manufacturers in their laboratory tests these devices for leaks, building codes do not currently require or recognize certification of smoke barriers for this indicator.

3. Ducts passing through fire-resistant partitions usually require the installation of fire dampers (although there are some exceptions). However, if this fire barrier must also be smoke-tight, few manufacturers can provide complete fire/smoke dampers that have a leak-certified perimeter seal. In fact, many valve specifications do not specify a perimeter seal, as the seal can interfere with thermal expansion of the valves. However, many local regulators require contractors to seal valves despite being out of specification.

4. Flame retardant devices are tested under laboratory conditions, which often do not correspond to reality. For example, some piping systems experience significant thermal elongation (displacement) and all piping is subject to seismic displacement. In tests by independent testing laboratories, pipelines are rigidly attached to fire barriers; this means that in real life the pipelines must be rigidly attached to each crossed fire barrier. When a valve manufacturer is asked if a seal is elastic, the answer is yes. When asked how elastic it is, he answers "more than 25%." When asked about the thickness of the sealant layer, he answers "1 cm". Thus, the physical value of the allowable displacement within the elasticity of the seal is 3 mm, which is less than the normal elongation of a steam line of not very long length. If each steam or condensate line is not rigidly attached to each fire barrier, the first time the system is used, either the pipe insulation or the flame retardant device will be damaged. Some specialty industries (for example, the manufacture of computer chips) use their own ideas, such as rubber gaskets (the same type that are found on the gear levers of front-wheel drive cars), to protect against smoke penetration through fireproof partitions.

Creating excess pressure in the stairwells

Although a detailed explanation of the technique for pressurizing stairwells is not provided in this article, it must still be pointed out that for multi-story buildings with many doors leading to stairs, pressurization is a problem.

An overpressure of 12 Pa gives a load on a 0.9 x 2 m door of about 2 kg. During a fire and smoke, the position of the doors leading to the stairwell differs from the usual one. A good design should determine how much pressure to maintain for smoke protection separately for "most doors closed" and "most doors open" situations, and how the excess pressure will affect the force required to open the doors. Assuming that the automatic control is working properly, a uniform overpressure in a high stairwell can be ensured by supplying air in several places. Do not forget to provide a place for wiring ducts to a variety of supply devices.

Some local codes allow simpler solutions instead of pressurizing stairwells. These include natural ventilation or smoke-proof ventilated shelters.


Reprinted with abridgements from ASHRAE magazine.

Translation from English by O. P. Bulycheva.

The calculation is carried out on the basis of methodological recommendations to SP 7.13130.2013 "Calculated determination of the main parameters of smoke ventilation

1. When calculating systems for removing smoke from open spaces for various purposes (halls) and atriums, designers allow underestimation of the minimum width of the room. In some cases, this affects the determination of the area of ​​the source of fire and, as a result, the performance of the smoke ventilation system decreases.

2. Making a mistake when choosing a fan for an exhaust smoke exhaust system: designers forget to bring the calculated static pressure of the fan to standard conditions. This can be done using the formula:

_____________________________________________ Psv = 1.2 * (PsmN + Pd )/ρsmN

Where P smN - static pressure in front of the fan (according to the calculation result) at the temperature of the flue mixture;
P d - resistance of air ducts and elements not taking part in the calculation when determining P smN;
ρ smN is the density of the smoke mixture at its temperature

3. When choosing a fan according to the graphs, there is a confusion of total and static pressure. The calculation determines the static pressure. And some manufacturer's nomograms are for full pressure. In this case, a fan with an underestimated performance is selected.

4. The bottom of the smoke exhaust damper must be higher than the escape door opening.

5. The valve of the compensating smoke exhaust system must be located in the lower part of the room. As a rule, at a distance of 500 mm, so as not to interfere with mopping.

6. The use of an exhaust smoke ventilation system without an inlet compensating one is unacceptable.

7. Imbalance in air during the operation of anti-draught ventilation is not more than 30%.

8. Determination of the flow rate of the compensating supply of fresh air for compensating the smoke exhaust system must be performed according to the mass flow rate (unit kg / s).

9. During the operation of smoke ventilation, the pressure difference on closed doors (especially evacuation doors) should not exceed 150 Pa. Otherwise, an adult will not open the door, and what can we say about children.

10. When designing corridor smoke exhaust systems, it is imperative to take into account the configuration of the corridor, see clause 7.8.

11. When designing a smoke ventilation system for stairs of multi-storey buildings of the H2 type, it is possible to divide into zones (arrangement of several valves) to reduce pressure on closed evacuation doors.

12. The removed products of combustion must be thrown out at a distance of at least 5 m from the place where the outside air is taken in by the supply smoke ventilation.

13. If the roof and walls are made of combustible materials, then the release of combustion products must be carried out at a height of at least 2 m from the roof level, otherwise protection with non-combustible materials should be provided.

14. The installation of common smoke ventilation systems for premises for various purposes is not allowed. For example, if the joint venture requires smoke removal from the meeting room and the corridor, then it is necessary to design two separate systems and it is prohibited to combine them.

15. When providing pressurization in a safe zone room, it must be taken into account that the supply air must be heated. As a rule, choose an electric heater.

16. In front of the fans of smoke ventilation systems, it is necessary to install check valves with electric drives (normally closed fire dampers with a reversible drive) in accordance with clause 7.11, clause 7.13, clause 7.17. If the valve is located outdoors, the valve must be electrically heated. It is worth paying attention to the fact that the installation of a gravity check valve is a violation of clause 7.19. Since this valve does not retain its position when the power is turned off.

In conclusion, I would like to add that the calculation and design of fire ventilation systems should be carried out by professionals. You can always contact our company for advice on smoke exhaust and air overpressure systems, as well as order a project.

Modern large industrial enterprises cannot be imagined without smoke exhaust systems. After all, they are considered emergency ventilation systems and provide the necessary conditions in order to evacuate people when a fire occurs.

A large-scale industrial enterprise cannot do without a smoke exhaust system in modern conditions. Such a system on an industrial scale is one of the elements of fire safety and makes it possible to create acceptable conditions for the evacuation of a large number of people from premises exposed to fire in the optimal time.

Design of smoke exhaust and protection systems. Appointment of smoke ventilation.

The main task of the system is to quickly remove smoke and combustion products from the room in case of fire. It is especially important to have such systems in areas where there is no free access to fresh air. It is also necessary to remove smoke and products of combustion along the route of people during the evacuation. At the time of a fire, a complex of engineering systems responsible for safety is activated (fire extinguishing, smoke removal, sound notification, access control, communication with services and other evacuation systems).

Objects where smoke exhaust systems are required

It is necessary to remove smoke in case of fire to ensure the safety of people. in a multi-storey building for any purpose (residential, business center, etc.), office buildings, shopping centers and other crowded places, in underground parking lots, in warehouses.

When do you need a smoke exhaust system?

Systems are necessary in absolutely any building, but their significance is updated where the movement of people is limited by objective reasons - for example, in places of detention, or hospitals, or high-rise buildings with intricate corridors. A sudden fire will sow panic, and in the absence of a smoke exhaust system, many people will die just because they did not manage to find the right way out in time.

Under such conditions, the smoke exhaust system will provide people with fresh air, concentrate carbon monoxide and prevent smoke from spreading through the premises, interfering with vision and breathing.

Often the system works in tandem with the ventilation of the room, so when developing the latter, experts pay attention to the selection of equipment that can continue to work in conditions of smoke and high temperatures.

System Benefits

Increased smoke during a fire is one of the causes of disorientation of people and, as a result, panic and possible death. Smoke extraction systems are very effective in dealing with this problem. In addition, one of their indisputable advantages is the localization of carbon monoxide dangerous to human health and life.

Principles of creating systems

The essence of ventilation and smoke removal systems is the same. The only difference is that for the formation of the smoke exhaust system, materials are used that ensure its normal functioning at high temperatures. This is achieved by using ferrous metals in their creation. A prerequisite for the installation of smoke exhaust systems is an agreed and approved project.

According to the principle of creation, systems are static and dynamic. A static system consists in simply turning off the ventilation system at the time of heavy smoke and, accordingly, stopping the spread of smoke. In this case, there is no installation of smoke extraction as such, which makes the static system very cheap.

The dynamic principle is considered more effective. The exhaust ventilation system in this case operates alternately to remove unsuitable air from the premises and supply fresh air. With a smoke exhaust system, it is possible to use several fans, each of which is endowed with its own function. At the preliminary stage, a technical task is prepared, our designers select the best solutions and prepare a smoke removal project for approval.

In some cases, a stand-alone system that is used only in emergency situations may be a suitable option.

Regulations

The regulatory framework (SNiPs, SP, GOSTs), which regulates the design, installation, testing of smoke ventilation, is constantly being finalized. Changes and additions are made to the standards to update these documents for modern realities. Ventilation must comply with all applicable requirements. Otherwise, the first fire check will bring a lot of trouble.

  • SP 7.13130.2009: Fire safety requirements. Heating, ventilation, air conditioning
  • GOST R 21.1101-2009: Basic requirements for design and working documentation
  • SP 60.13330.2012 (SNiP 41-01-2003) - Heating, ventilation, air conditioning
  • GOST 21.602-2003: Rules for the execution of working documentation for heating, ventilation and air conditioning

How smoke ventilation works.

Most effective automatic system. Sensors and a control panel are located on the object. If the signals from one or more sensors indicate the presence of a fire, it automatically opens smoke damper and air is pumped out of the room. There are also systems that are started manually from the central console or using special buttons located in easily accessible places.

Equipment for smoke exhaust systems

Smoke removal implemented in various ways. Smoke exhaust fans can force air, which leads to the expulsion of combustion products into the exhaust channels. Also, fans are installed in the channels and work on the hood. Increased requirements are set for smoke exhaust equipment (resistance to high temperatures, reliability of operation in extreme conditions, etc.).

Design features

It is mandatory to calculate the parameters of the system, taking into account all the characteristics of the object. The number of smoke intake devices, the power of the equipment are determined, automation is selected, a decision is made on the type of ventilation. Design solutions must necessarily meet the requirements of regulatory documents.

System maintenance

Maintenance must be carried out regularly to ensure trouble-free operation of the system in the event of a fire. It includes checking the integrity of the air ducts, the health of valves, fans, sensors and other elements of the system. Security systems must be checked for quality of work, measured and updated technical reports, which are presented at the request of the inspector.

In the absence of a project, as-built documentation, protocols for checking security systems, the inspection organization can issue fines, issue instructions to eliminate shortcomings, and even close / seal the facility. We recommend that you carry out checks of engineering systems in advance and.

Project OV Smoke removal Production and warehouse base

LLC "Darna" MO, Istra district

System selection

When choosing one or another smoke exhaust system, it is highly desirable to be guided not only by savings. The choice should be optimal, first of all, from the point of view of safety - in this case, it is necessary to consult with VeerVent specialists who provide professional assistance in the selection and installation of smoke exhaust systems. In addition to consulting assistance, our employees successfully carry out the installation of these systems throughout Russia.

The VeerVent company performs both smoke removal design and installation using certified equipment that meets all building rules and regulatory documentation, followed by commissioning.
The VeerVent team is a team of professionals with extensive experience.

Operation of the smoke exhaust system

The smoke exhaust system is not used to extinguish the fire. Its main goal is to ensure the evacuation of people from the building, and in particular, to ensure that rooms, corridors and stairs are smoke-free. In a fire, the worst thing is not the fire, but the smoke. Carbon monoxide or "carbon monoxide" in doses of 0.4% leads to death. For 2-5 minutes of exposure to a dense layer of smoke, a person loses consciousness.

TASK #1. Ensure smoke-free escape routes from the building;
TASK №2. Ensure access for fire departments.

The smoke exhaust system (synonymous with smoke ventilation) is an exhaust and supply smoke ventilation combined with it. Prior to 2009, inlet smoke ventilation was not installed in the design standards, but in practice, the monstrous volumes of exhaust air led to the intake of doors and made evacuation difficult.Therefore, in 2013, the rules were supplemented.

Today (2018) supply smoke ventilation is mandatory! The main task of the inflow is to compensate for the removed air. We supply fresh air only for the evacuation of people, there is no question of any fire extinguishing.

The exhaust smoke ventilation system removes from 18,000 to 30,000 m3/h of air from only one corridor. This volume of air is comparable to the general ventilation of an office building with an area of ​​3,000 m2 or more. This volume of air can be used for breathing from 400 to 700 people.

When is smoke extraction needed?

There is very little information on the Internet about exactly where a smoke ventilation system is needed.
Smoke exhaust standards are written in complex language and are scattered across various regulatory documents. In this section, I have collected the most important information. You just have to go through the list and understand - is a smoke ventilation system required in your particular case?

Exhaust smoke ventilation (smoke exhaust) system is required:

1. from the corridors and halls of any buildings more than 9 floors, except for production;

2. from the corridors in the basement and basement floors any buildings where there are premises with a permanent stay of people on these floors;
For example, smoke removal is required from the corridor of the basement floor of a residential building where offices or workshops are located. At the same time, if the exit from such an office occurs immediately to the street, smoke removal is not required.

3. from corridors longer than 15 meters without opening external windows;
Smoke removal from such corridors is not required in one-story buildings and industrial buildings with non-combustible substances. It is also not required if there are no permanent workplaces in all rooms of this corridor, and the doors from the rooms are made in a smoke and gas tight design.

4. from atriums and passages ;

An atrium is a multi-storey hall, a common space with stairs connecting several floors of a building.

5. from warehouses with rack storage more than 5.5 meters high, where materials capable of burning and igniting are stored;

6. from production and storage facilities, but only with the constant stay of people, where materials capable of burning and igniting are used;

Permanent stay of people is more than 6 hours a day or 2 hours continuously during the day.

7. from production and storage facilities with permanent residence of people, in wooden buildings or buildings made of other combustible materials;

8. from the premises without opening outer eyesn area over 50 m2:
8.1 with mass stay of people, mmass stay - there is more than 1 person per 1 m 2 of free space. For example: meeting rooms, classrooms, dining rooms, auditoriums of theaters and cinemas. Actual for all rooms where there are a lot of people and few windows. Often, a smoke removal project is ordered from the dining room of a restaurant in the basement along with the project.
8.2 c permanent workplaces where combustible materials are used or stored. For example: reading rooms, book depositories, exhibitions or archives without opening windows

9. from the premises without opening outside windows regardless of area
9.1 trading floors of shops;
9.2 offices;
9.3 dressing rooms with an area of ​​​​more than 200 m 2.

Smoke removal not required from trading floors (9.1), offices (9.2), if the premises are less than 800 m 2 located on the 1st floor residential building or attached to a residential building and has access immediately to the street, while from the farthest room to the exit should be no more than 25 m.
For example: If the office is less than 800 m2, but more than 25 m from the farthest room to the exit, smoke removal will be required.

9.4 road and communication tunnels when they are connected to the underground floors of the building.

10. from any covered car parks , as well as isolated ramps for cars to enter the floors.


Smoke removal system from car park. The use of jet fans for parking lots is not regulated by Russian standards!

11. from any premises that have access to smoke-free stairwells , regardless of their area and the presence of opening windows.For example, a corridor is less than 15 meters, but the exit from it is through a smoke-free stairwell. In this case, we make a smoke exhaust system in the corridor, and the inflow into the stairs.

A smoke-free staircase is an internal staircase for evacuating people in case of fire in buildings over 9 floors (or over 28 meters high).It is necessary that the premises in question fully comply with all the conditions listed in the paragraph. If any requirement for the room is not met, smoke removal is not required.

Supply smoke ventilation system

The supply smoke ventilation system is a compensation system.
The main goal is to ensure the free opening of escape doors. The air supply of such a system is carried out in the lower part of the room, i.e. in the part of the room below the upper cut-off of the doorway.

As an inflow to compensate for mechanical smoke ventilation systems, the following can be used:

  • external windows in the lower parts of the room with automatic drives;
  • openings in the outer walls and shafts with valves;
  • mechanical support (using a fan).
Opening in the outer wall to compensate for smoke exhaust

First way is used extremely rarely for the reason that it creates the possibility of "favorable misunderstanding" on the part of the inspection bodies.

Second way is used more often, but has one difficulty - the huge dimensions of the mine. In foreign standards, the size of the smoke exhaust shaft is calculated from an air speed of not more than 1.5 m / s, and in Russian - 5-6 m / s is allowed. In the case of using such a shaft, for example, to compensate for smoke removal from a corridor, we get a duct size of at least 1000x600 mm. The height of the air duct laid under the ceiling, namely 600 mm, will make it difficult to lay adjacent communications and greatly lower the final ceiling.


Options for supply smoke ventilation. On the left is a mechanical backwater (fan). On the right is a natural tributary mine

Third way- mechanical support with a fan - more convenient, but also a little expensive.


Roof axial fan for supply smoke ventilation without confuser.

The dimensions of the air duct in this case will be significantly smaller, say 800x400 mm. There are no restrictions on air velocity in mechanical smoke ventilation systems and there cannot be. The system works only in case of fire, therefore it is not taken into account in the overall balance of electricity consumption.

In the case of mechanical backwater, we will have to buy a fan, equip it with an automation cabinet and a frequency converter in accordance with GOST R 53302-2009, but this is a more reliable option than all the others.

Can not use as an inflow opening of external doors and gates, because escape doors must be equipped with self-closing devices. This derogation is possible only in the case of atriums and arcades.

Can be used as compensation, ordinary general ventilation, but in practice this is not convenient. Firstly, the volumes of supply air in general exchange and smoke ventilation differ by an order of magnitude, which leads to an increase in the cost of ventilation equipment.Secondly, the requirements for the ventilation system are becoming more stringent and must comply with the requirements of the smoke ventilation system.
It is cheaper to make two separate independent systems.

What will happen if you do not make a smoke exhaust compensation system.

FROMwatch the video below.

Exhaust smoke ventilation system

The choice of system directly depends on the number of storeys of the building.In one-story buildings, it is allowed to design a natural smoke exhaust system, i.e. self-opening valves in the roof and transoms.In buildings over 1 floor - a mechanical smoke ventilation system.

It is necessary to constructively divide the room into smoke zones, up to 3000 m2 each. Each zone has its own separate system. Otherwise, the smoke spreads along the ceiling of such a huge room. The temperature of the smoke decreases, and consequently the gravitational pressure also decreases. The rule is non-negotiable.

Natural smoke extraction

In a natural smoke exhaust system, as in any natural engineering system, there is one big minus and one big plus. The advantage is that the system is passive, i.e. does not require large capital expenditures, does not consume electricity and has a minimum of working mechanisms that should be checked and maintained. And the minus is in ensuring the stable operation of such a system.

Regulations oblige us to provide wind protection for such roof flaps and transoms, which we absolutely cannot guarantee.

Natural smoke extraction does not require a compensation system. The calculation of the natural smoke exhaust system is carried out depending on the shape of the room, the type of fire load (what exactly is burning), the area and the possible location of the fire.

Natural smoke hatch on the roof of the warehouse complex
Natural smoke hatch in operating mode with rack and pinion drive

The natural smoke exhaust system is used only in one-story buildings: warehouses, warehouse-type shopping centers, production workshops. The equipment of such a system in buildings with more than one storey is prohibited.

Mechanical smoke exhaust system (roof fan and wall fan)

The mechanical smoke exhaust system is powered by an exhaust fan. Typically, smoke exhaust fans are of 2 types - roof and wall. Both fans perform the same role, but in completely different situations.

It is installed on top of the smoke exhaust shaft on the roof and removes smoke from all floors of the building, throwing it vertically upwards. The complexity of installing such a fan lies in the complexity of the design of the mounting frame. For a long time, there were no ready-made mounting frames for such fans, and it was necessary to develop an additional section of project documentation, in which the dimensions of such a design were calculated. The second difficulty is in the type of fans.


Roof mechanical smoke exhaust fan with a vertical riser on the mounting sleeve.

The roof fan is designed for installation on a shaft and should be located at a height of 2 meters from the roof, or at a lower height, but in this case it is necessary to make a roof only from non-combustible materials.

The simplest solution for placing smoke exhaust fans on the roof, I think, is axial roof fans or duct smoke exhaust fans. They do not affect the waterproofing of the roof. Does not require installation of additional shafts and frames.

Air ducts of smoke ventilation systems can be made of any type of steel, but with a fire-retardant coating. It is possible to use both welded, rebated and spiral-wound air ducts with the only requirement: the thickness of the steel sheet is at least 0.8 mm.

Wall fan, unlike the roof, is local, i.e. can work on a specific floor, and throw combustion products through the grate on the facade of the building. This allows not to lay air ducts through all floors to the roof and not to equip an exhaust shaft. The fan is placed on the outer wall of the floor, either from the street or indoors.


Wall-mounted smoke exhaust fan (outside the building) with an exhaust pipe, providing a jet speed of at least 20 m/s. (SP7 clause 7.11 d)
Wall-mounted smoke exhaust fan (inside the building). Engine in a thermally insulated casing with an additional channel for cooling.

For smoke removal from parking lots, large retail areas, wall fans are most likely not suitable. The maximum flow rate of the removed air is 35,000-38,000 m 3 /h. But for smoke removal from corridors, small office and retail premises - a great idea.

How to avoid installing a smoke exhaust system?

The main problem with the system is its size and cost. The minimum section of the smoke exhaust duct is 800x500 mm or 1000x300 mm, both sizes being extremely rare. There are a number of measures that legally compensate for the smoke exhaust system, i.e. exclude installation requirements.

− Common decision . Justify the lack of smoke removal by calculating fire risks. The calculation does not apply to apartment buildings, children's institutions and medical hospitals.
− For any premises up to 200 m2 . Equip an automatic fire extinguishing system. Including equipment with a modular system is possible, which is less expensive and practical.
− For trading floors, offices and corridors over 15 m . Add to the recreation room with external opening windows.
− For exhibitions, archives, workshops and book depositories(if point 2 does not apply)– justify the rejection of the smoke exhaust system by the lack of permanent jobs in accordance with the project of architectural solutions.

Algorithm for starting the smoke exhaust system

The fire smoke exhaust system must be activated from three independent signals:
- from the "Fire" button from the security console;
- from the "Fire" button installed in the corridors on the evacuation routes;
- from the operation of two or more fire detectors in one specific zone (on the same floor).

The procedure for starting smoke exhaust systems:

Turning on the system from one of 3 independent signals;
sound notification of people about a fire alarm;
shutdown of general ventilation systems, air conditioning and air-thermal curtains. Closing fire dampers on the ventilation system;
lowering the elevator to the 1st floor of the building and opening the doors;
starting the fan and opening the exhaust smoke ventilation valves;
start of the fan and opening of the supply smoke ventilation valves (20-30 seconds after the exhaust ventilation).

It makes no sense to do smoke removal from underground passages.

Smoke exhaust design

You can order a smoke removal project from me without intermediaries. I will go to the site and design the system.
The cost of working documentation for smoke removal is from 25,000 rubles. (for remote control from the corridors) up to 75,000 rubles. (for remote control of apartment buildings and small shopping centers).
Strictly in accordance with the smoke exhaust design standards SP 7.13130.2013, SP 5.13130.2009, SP 2.13130.2012.
I perform the calculation according to the methods of R NP "ABOK" 5.1.5-2015 and VNIIPO 2013
My contacts +7-963-729-71-20 (Aleksey)

The answer is simple - they are designed to clean the atmosphere in the premises from combustion products for the safe evacuation of people.

Which rooms need smoke extraction systems?

It may seem that smoke exhaust systems are a tribute to the times, and there is no urgent need for them. However, it is not. There are public buildings and premises where such systems cannot be dispensed with in the event of an emergency.

It:

  • · catering establishments (canteens, bars, etc.);
  • administrative buildings with a large staff;
  • entertainment and shopping centers;
  • premises that gather a huge audience.

In all of the above places you can not do without equipment from VOSStroy. The company's professionals carry out the design of a smoke exhaust system and turnkey installation.

What is the difference between conventional hood and smoke extraction systems?

To fully clean the air inside the room, conventional air ducts are not enough. They are usually made from materials that do not withstand elevated temperatures. Components melt, adding gas content. If a separate segment of the ventilation system fails, its function will be impaired.

Another danger is the spread of fire. This occurs during the burnout of individual sections of ventilation. That is why the air ducts of smoke exhaust systems are made of steel with a refractory layer. It withstands extreme internal temperatures without burning through external fire.

The smoke exhaust system does not use a duct fan. There are several reasons for this:

  1. The fan is not resistant to fire, like ordinary ventilation systems;
  2. The fan motor is located inside the box. At high temperatures, it fails;
  3. A banal fan is not able to remove smoke from rooms equipped with air ducts.
The reason is low power.

Only special centrifugal fans, called "smoke exhaust fans", are capable of fully extracting smoke. Their level of operating noise exceeds the performance of analogues. But there is no alternative to them.

Creation of smoke exhaust systems

Getting started is a project.

The creation of a smoke removal system takes place in the following steps:

1. Obtaining an order for the execution of the project (terms of reference).

2. Implementation of design activities.

Specialists receive complete data on the premises, examine them, and look for the possibility of installing the system. This determines how feasible the task is in a particular building. After all, the cross-sectional area of ​​\u200b\u200bcommunications should be unchanged over the entire length. The thickness of the duct wall and the insulation layer must be taken into account. Therefore, the system design process is carried out on an individual basis in order to optimally place the pipe in a given room.

3. Direct installation of the system.

This is the final stage.

It comes from the moment the project documentation is prepared and the necessary approvals are received.

The specificity of air ducts is a solid mass. It is taken into account during the installation process. The possibility of covering with protective materials directly on the object is also important. The choice of the client is provided with special heat-resistant mats attached to the walls of the structure, or a jelly-like quickly hardening composition.

Smoke exhaust fans are mounted on the roof. The reason is the desire to extend their service life. The valves of the system are installed according to the project documentation.

Price of installation and accessories

Calculating the cost of the system is a complex and responsible process. It depends on the given room and building. Therefore, it is better to entrust it to professionals. The company "VOSStroy" will provide you with:

  • preparation of the project with obtaining the necessary approvals from the Moscow supervisory organizations (optional);
  • a real estimate of the complex of works;
  • contract for the supply and installation of a smoke exhaust system (no hidden fees);
  • factory quality materials;
  • high-quality fans and delivery on time;
  • qualified installation work without disrupting the deadlines and your activities;
  • system testing.
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