Smoke-free stairwells type n1. Smoke-free staircases: types

Dear! You have "error in the root folder".

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:))))))))))))))))))))))))))))))))))))))))))
And you seem to have only the dorsal brain, or are you the same standard-setter who !!! sometimes !!! pushes his delusional thoughts into fire regulations.

Quote Kruger 08/22/2012 09:52:41

For example, an office building, and a canteen building (polyclinic, savings bank, sports club, etc.) is attached to it. There is one fire compartment, and there are two buildings (and, possibly, built at different times).

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I understood what was the matter.
You are hinting at what is written in the rules:
clause 5.3.2 SP4
"!!! BUILDINGS!!! of objects of cultural and entertainment purpose intended for stay (or with an estimated number of places) of more than 50 people, attached to objects of other purposes within
area of ​​the fire compartment should be separated by fire walls of the 2nd type.

Clause 5.4.2.1
"!!!Buildings!!! of trade facilities attached to public facilities for other purposes within the area of ​​the fire compartment should be separated by fire walls of the 2nd type."

These are the words!!! BUILDINGS!!! You were confused.
Uv.Kruger ®, you think exactly like the rule-maker who wrote this rule, and you just don’t want to think a little further. I repeatedly quoted from the film that "The commander must first of all think, and not just wave his saber." But, it seems to you that your back does not succeed in any way, well, or are you really the same about whom I wrote above (!!! STANDARD SET KRUGER !!!)

I will give you another example of writing a norm, which apparently was written by your more competent colleague.
see clause 5.4.4.2 of the same SP4 and what we see with you, and we see the following:
"The specified objects, attached to public facilities for other purposes within the area of ​​the fire compartment, should be separated by fire walls of the 2nd type."

Or another paragraph 5.4.5.1 of SP4:
"Objects of household and communal services organizations, if they contain premises of the functional fire hazard class F5, attached to public buildings for other purposes within the area of ​​the fire compartment, should be separated by fire walls of the 2nd type"

Oh, and one more thing, just to make it clear to you:
clause 5.4.6.2 SP4
"Sports complexes attached to public facilities for other purposes within the area of ​​the fire compartment should be separated by fire walls of the 2nd type."

As we see nowhere is the word!!!BUILDING!!! do not appear, but the FUNCTIONAL purpose of the attached !!! OBJECTS is given !!!

So, SW Krueger ®, you finish with rationing, you are not good at it.

Quote Karamba 08/16/2012 02:25:22 PM

Administrative buildings of industrial buildings

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Definitions of uv.Karamba, what is administrative life. I think you will not find the building of the production building, but probably these are buildings (buildings) connected to the main production building, through passages according to clause 6.7.4 of SP2.
Apparently this is what we're talking about here.

A prerequisite in multi-storey buildings is the presence of a smoke-free staircase, which can be the only way to escape in the event of a fire. For such structures there is a special classification. Each type of cell has its own design features, which should be considered in more detail.

Design purpose

The first thing to start with is the question of the functional purpose of smoke-free stairs. This design is a march of certain sizes, which should be located in a suitable area of ​​\u200b\u200bthe building.

Smoke-free staircases are designed to serve as an emergency exit for people in this building. The main focus is on the fire emergency. The consequence of any scale fire is the smoke of the interior space of the house. Many people who died in a fire were negatively affected by smoke and toxic fumes, and by no means flame. That is why one of the main requirements for an emergency exit is isolation from smoke.

In addition, this type of ladder should allow rescuers to reach the interior to extinguish the fire and rescue injured people. In particular, it is possible to carry people on stretchers.

The presence of smoke-free staircases is a prerequisite for high-rise buildings. Depending on the specific type, different requirements are imposed on them.

Smoke-free staircase performs the function of evacuating people in case of fire

Main types

There are several types of smoke-free staircases. They are classified by location, access to them and the principle of operation. Consider the standard types of smoke-free stairs:

• H1. This is the base model. For such a design, the characteristic features are the availability of access through an open area. The approach to the emergency exit must also be smoke-free.
• H2. For such stairs, air support is provided in the event of a fire.
• H3. They are very similar to type H2, but in this case, access to the march is provided through a vestibule lock. Additionally, the same air support is provided, but it can be supplied both in case of fire and on an ongoing basis.

Standard types of smoke-free staircases

In order to better understand the difference between these types of stairs, you should consider the types H1, H2 and H3 in more detail and identify the most characteristic features for them.

Stairs H1

The presence of a smoke-free H1 type staircase is a prerequisite for residential and public buildings of any plan with a height of 30 meters or more. The peculiarity of this design is, first of all, in providing access to it. In order to get to the stairs of type H1, you need to go along the corridor to an open area of ​​​​the outdoor type. It can be a balcony, a veranda or a fenced area outside the premises.

Passing through the open segment, you will find yourself in that part of the building where the location of marches of this type is provided. Such requirements are due to the need to provide natural isolation of the evacuation exit from the smoky part of the building. Therefore, the best option for their placement is the corner part of the building. A particularly advantageous position is the inner corner with additional piers. It is advisable to provide for the presence of a fenced evacuation exit even in the process of designing the building itself, so that in the future it would not have to be converted to fire safety requirements.

Stairwell type H1 is mandatory for residential and public buildings

Stairs H2 and H3

Another design option is smoke-free staircases marked H2 and H3. They are placed in buildings with a height of more than 50 meters. Mostly in modern buildings, it is models of the H2 type that are used, so you should start with them.

For smoke-free staircases of the H2 type, the characteristic features are the presence of an air backwater. The exit to it remains within the inner part of the building, but the presence of a ventilation duct is mandatory. It is thanks to this design that the requirements for air overpressure in the stairwell are met.

More complex in execution are stairs of the H3 type. They provide for the presence of an additional vestibule located on the way to the emergency exit. It is thanks to this extension that the best protection against fire and smoke is provided. In the vestibule, it is planned to use non-combustible materials to remove walls and partitions, and a fire door is also installed, preferably with an automatic porch.

The very design of the staircase remains the same as for the H2 model. The ventilation duct provides air supply and adequate passage pressure. As a result, the ingress and accumulation of smoke and other combustion products in the territory of the emergency exit is prevented.

Stairs type H2 and H3 must be placed in buildings with a height of more than 50 meters

In addition to structural features, it is also important to comply with the requirements of SNiP regarding the dimensions of the passages and the materials used. If violations are detected, the ladder will not be able to fully perform its functions and can be very dangerous in the event of a fire.

Exit to the stairs

In order for the staircase to remain smoke-free even in the case of a close location of the ignition source or in the event of a large-scale fire, it is necessary to ensure the availability of safe approaches. Basically, the emphasis is on the presence of fire partitions and special doors. They must be made of non-combustible and non-toxic materials, all joints are additionally sealed and the degree of resistance to high temperatures and open fire is checked.

The main requirements for exits to this type of evacuation staircase are as follows:

• Lighting. To ensure sufficient visibility, the stairs must be equipped with light sources. According to the rules, windows should be provided on the stairwell of the evacuation type. Auxiliary and emergency light sources are also mandatory.
• Ventilation. To ensure air supply, it is necessary to build a ventilation shaft associated with marches. A hole is left on the top tier to ensure constant air circulation. In some cases, forced provision of this process with the help of ventilation equipment is required.
• Partitions. To prevent the penetration of fire into the territory of the emergency exit, it is necessary to provide additional partitions on the way to the main part of the building. A distance of about 2 meters must be maintained between the elevator shaft and the evacuation passage.
• Free access. In order to get to the cage there should be no obstacles on the way. It is forbidden to block the passage and place objects on its area for both permanent and temporary storage. It is strictly forbidden to close the doors leading to the exit or install additional obstacles on the way to it. The passage must remain open around the clock.
• Information access. People in the building should be aware of the presence and specific location of the emergency exit. For this, a prerequisite is the presence of special signs and an evacuation plan directly.

Requirements regarding exit to the evacuation stairs

Dimensional requirements

In addition to the above requirements for smoke-free stairs, other conditions are also imposed, they relate to the size of the cage and the marches themselves. In order to systematize these indicators, they can be divided into the following groups:

• Height. In order for the average person to move comfortably along the evacuation route, the height of the ceilings in the march area should be at least 190 cm.
• Width. The dimensions of the passage should be 120 cm wide in the air zone. The width of the path to this passage must be at least 110 cm. The unhindered movement of two people must be ensured, as well as the transfer of victims on a stretcher.
• Number of steps. Within one march, a maximum of 16-18 ordinary steps is allowed.
• Step dimensions. The optimal ratios are taken as the basis, which are established for all types of stairs. The step should be wide enough for comfortable placement on its surface of the foot. At the same time, its height is about one and a half times smaller. All elements of the march must be the same in terms of parameters. The slope varies on average from 30 to 40 degrees.
• Number of people. In most cases, standard evacuation marches are limited in terms of the simultaneous presence of people on the cage. Often this number is 15 people, but the exact value depends on the dimensions of the building and its purpose, as well as the type of staircase.
• Handrails. To minimize the risk of injury and facilitate movement, barriers and handrails made of non-combustible materials are mandatory. It is important to consider that they must have a minimum thermal conductivity to prevent them from heating up in case of fire.

Acceptable materials

A smoke-free staircase is often made from materials that are able to withstand heat as much as possible and, of course, not ignite when in contact with high temperatures and fire. That is why the favorites are:

• Metal. It is usually used when it is not possible to build a massive structure. The internal structure of concrete marches is strengthened with metal elements, and fences are also equipped.
• Concrete. The leader in use, as it is completely fireproof. In addition, concrete marches are quite comfortable and durable, they meet the standards for dimensions and other requirements of SNiP. Concrete is used for the construction of internal evacuation structures.

Evacuation ladders are most often made of metal or concrete.

Alternative designs

In addition to smoke-free stairs, other types of structures for special purposes can also be used. The main alternative to a non-smokeable staircase of type H is an evacuation model of category L. Such structures are often installed in buildings with a lower number of storeys. In general, they repeat the requirements of the cells described above, but there are some design features of these models.

Fire escapes should also be mentioned separately. They are used to facilitate the process of rescue operations and fire fighting, and can also be used to leave the building, but this is an extreme case. They are smaller in size and are placed outside the building at a certain distance from the walls.

If smoke-free stairs do not meet the requirements of SNiP, they are allowed to be used only in the form of emergency passages. In this case, it is necessary to ensure the presence of serviceable evacuation exits. Without them, it is not allowed to put the building into operation according to the rules.

Jargon used in fire safety design of buildings.

On the website of VNIIPO EMERCOM of Russia, the opinion of specialists from this institute is given regarding the use of the indicated name in relation to stairwells of the H2 type, the exit to which goes through a tambour lock with air overpressure.

Considering that the EMERCOM of Russia periodically “cleans” the question-answer sections on its websites, we consider it necessary to cite this opinion here, with reference to the original source.

Question asked by VNIIPO EMERCOM of Russia:

VNIIPO answer:

The use of the phrase “smoky H2+H3 stairwells” is essentially a typical jargon that has nothing to do with the normatively established classification, and, in a number of ways, contradicts fire safety requirements. In particular, in accordance with the provisions of the Federal Law of July 22, 2008 No.

No. 123-FZ "Technical regulations on fire safety requirements" fire-technical classification provides for only three types of smoke-free staircases: H1, H2 and H3.

Moreover, for stairwells of the H2 type, non-smoking (or preventing the spread of combustion products into their volumes during fires in buildings) is provided by supply smoke ventilation by supplying outside air to these volumes to create excess pressure in them relative to adjacent rooms, corridors, halls on different floors. Floor-by-floor entrances to non-smoky H2-type stairwells are arranged through single or parallel doorways (floor-by-floor entrances are allowed through sequentially located doorways in vestibules provided exclusively for operating technology conditions, but not for additional fire protection). In turn, for stairwells of the H3 type, smoke-freeness is achieved by installing tambour locks at all floor entrances, which are protected by inlet smoke ventilation that provides outdoor air supply to one of these tambour locks (when leaving the floor on which the fire broke out) with the creation of excess pressure in it relative to adjacent rooms, corridors, halls.

note

Thus, each of the considered established types of smoke-free staircases corresponds to a specific design of a single staircase in conjunction with the space-planning elements of the building.

Consequently, the used symbolic addition “H2 + H3” is clearly meaningless: it physically combines various spatial structural elements - two separate stairwells of different designs (at the same time, according to the laws of algebraic addition, a casuistic non-existent type of non-smokeable stairwells is obtained - H5).

In addition to the noted absurdity of physical perception, such an innovation of “smoke-free stairwells of the H2 + H3 type” does not allow to fully implement the existing regulatory framework in all aspects of the use of smoke-free stairwells in buildings for various purposes.

In this regard, even if we exclude from consideration the impossibility of the physical implementation of this "innovation" and analyze only the forced combination of the principles of ensuring smoke-free operation, characteristic of both of these types of staircases, then regardless of the design features of the building part of buildings, it becomes necessary to install on all floor entrances of smoke-free stairwells of type H2 tambour locks, protected by inlet smoke ventilation (a graphical interpretation of such a conclusion is given in Fig. 1 and 2).

At the same time, according to the current requirements of SP 7.13130, such use of vestibule locks on all floors is not required.

For example, when arranging an internal exit from a smoke-free staircase of type H2 to the lobby of the lower floor of the above-ground part of the building (without dividing it into fire compartments), a normative separation of such an exit from the lobby by a vestibule-gateway protected by inlet smoke ventilation is required (Fig. 3).

At the same time, on the upper floors, an additional device of vestibule locks at exits to the stairwell is not required.

In the case of dividing the building part of the building into fire compartments, the arrangement of tambour locks protected by inlet smoke ventilation is necessary at floor-by-floor exits to a non-smoke-proof H2-type stairwell only on the floors of the lower fire compartments while maintaining the usual single doorways on the floors of the upper fire compartment (as it is shown in Fig. 4).

Thus, taking into account the noted features of the design of smoke-free staircases, it is necessary to unconditionally comply with the current regulatory requirements for fire safety in accordance with the established fire-technical classification - without any unreasonable, including jargon "innovations".

Classification of staircases for fire safety

Having visited the houses built according to the projects of various construction companies, you can see that the staircases in them are very similar and have only minor differences. The reason for this is the safety regulations in force, which have been put in place to minimize the risk of casualties in the event of a fire.

The standardization of these elements helps citizens quickly leave the building, and firefighters and rescue teams make it much easier to fight fires, since they know the structure in advance.

So what are the types of staircases?

Depending on the presence or absence of insulation, ordinary (L) and non-smoky structures (N) are distinguished.

Type L1

This type of staircase assumes its integration with the corridor leading to the apartments and the elevator. The lighting of the staircase passages of this design occurs naturally through small glazed windows, or through open openings on the walls facing the street.

Homeowners in such homes must exercise a responsible attitude to safety and not block the path of a possible evacuation. An important requirement is a ban on the placement of power cables in the stairwell, since their malfunction can turn the means of ensuring the safe exit of citizens outside into a trap.

There is a limitation on the use of this design: it can be used in buildings whose height does not exceed 28 meters (the indicator is determined by the floor line of the last floor). In practice, we are talking about houses consisting of no more than 10 floors.

Type L2

This design option, like the previous one, is not isolated from the corridors of the rest of the building. Its main difference from type L1 is lighting, which is carried out in a natural way through glazed or open openings in the coating (overhead lighting).

Stairwell type L2 is approved for use in buildings whose height is not more than 9 meters. This is due to the fact that the only source of light can be blocked as a result of smoke, which can disorient citizens during the evacuation.

Type H1

In buildings with a height of more than 28 meters, the use of smoke-free staircases is mandatory. This requirement is due to the fact that if using the usual design for citizens evacuating from the upper floors, there would be a high risk of carbon monoxide poisoning. Another factor is the limited capacity of fire and rescue equipment.

Type H1 is most often found in high-rise buildings. It involves separating the staircase from the corridors near the apartments and elevators with the help of an open passage, which is a loggia or balcony. In the event of a fire, the smoke exits through the passage without getting on the stairs.

Type H2

The design of the H2 staircase differs from the previous version in that the passage to it is closed.

Isolation from the source of smoke is provided by means of forced ventilation. It starts working after receiving a signal from sensors that detect the presence of smoke and allows you to create an air backwater. In order not to create a dangerous draft of air from the fire source, the exit to the stairs is separated by sealed doors.

The ventilation system itself is located inside the staircase.

The design H3 is distinguished into a separate type of staircase. However, it differs only in the location of the air boost system, which is located inside the transition.

Requirements for smoke-free staircases

Along with the safety standards that determine the design of the staircase, there are also requirements related to its individual elements. And this is necessary, since each of them can affect the overall effectiveness of a building's fire protection.

Fire doors

Regulatory requirements provide for the presence of fire barriers. One of their elements are fire doors that fill the openings. They must have the following properties:

• Metal outer part;
• Filler of fire-resistant substances;
• Coating of metal with non-combustible coloring materials.

The marking of fire doors involves the use of the letters E, I along with a numerical value, where:

• E characterizes the loss of the integrity of the door, due to the formation of holes and cracks in it, through which flame or smoke penetrates;
• I denotes the loss of the heat-insulating function, in which there is a temperature effect that destroys the surface of the door that is not facing the flame.
• The numeric value determines the number of minutes after which the above changes occur.

Dimension of the ladder for evacuation

The current standards determine the dimensions of many elements of the staircase:

• The width of the flight of stairs;
• The slope of the stairs and the size of the steps;
• The height of the fence;
• The width of the staircase.

The flight of stairs must have a width not less than the same parameter of the exit (door) to it.

Separate requirements are established for buildings used as kindergartens, hospitals, institutions for the elderly and disabled, as well as in the case of their use to accommodate boarding school students during sleep. The required march width in these cases is 1350 mm. This allows you to speed up the evacuation of these categories of citizens.

If more than 200 hundred people are simultaneously in the building on the floors above the first, the width of the flight of stairs should be 1200 mm. This decision will also speed up the evacuation, minimizing the risk of stampede and panic.

The slope of the stairs must have a ratio of 1/1 and a minimum tread depth of 250 mm. The riser must be no more than 220 mm high.

Stairs must be equipped with a railing (railing), the minimum height of which is 1200 mm.

The landing should have a width equal to the width of the flight of stairs. This is done in order to eliminate the effect of the "bottleneck" and the panic caused by it.

Walls

The main requirement for the inner walls of a smoke-free staircase is the absence of any openings, except for the door.

In the case of using walls as one of the elements of fire barriers, they, like fire doors, must have fire-resistant properties. In this case, the parameter R is added to the indicators E and I, which characterizes the time of maintaining the load-bearing properties in case of fire.

Illumination standards and light opening

The outer walls of the staircase must have windows with a glazing area of ​​1.2 sq. m. The distance from the stairway to the window cannot be less than 1.2 m. This is done so that natural light falls on the flights of stairs.

Type H1 cages are equipped with opening windows, while the height of the opening device cannot exceed 1.7 m.

Due to the presence of forced ventilation systems, H2 stairwells are equipped with windows that do not open.

Internal open staircase

Under the internal open staircase understand the transition between floors, located outside the staircase. If there is no wall on at least one side, then the staircase fits this definition.

Often this design is decorative and has limited evacuation use. Current regulations require a redundant output.

double ladder

This design is based on the use of two symmetrical flights of stairs, which are directed to a common area. This solution is becoming increasingly common due to its decorative properties.

From the point of view of safety, the structure should have a platform and a subsequent single (if any) march, ensuring the minimization of congestion during the evacuation of citizens.

Smoke-free staircases (H1, H2, H3) and fire evacuation stairs

The current level of development of scientific and technological progress does not in any way affect the existence of the fact that fire has been and remains one of the most dangerous enemies of human habitation for thousands of years.

Despite the widespread introduction of rules requiring the use of exclusively non-combustible materials for interior decoration, the statistics remain relentless: people's homes today are by no means invulnerable.

Often the only thing left in the event of a fire for the residents is to flee, that is, to evacuate. The safest way to escape from multi-storey buildings is fire evacuation stairs.

The danger to people in case of fire is not only fire. The smoke is also dangerous. But the most terrible invisible enemy is carbon monoxide.

A person may not notice its effects (unlike ordinary burning, carbon monoxide has neither smell nor color). Carbon monoxide poisoning is characterized by rapid development.

After a few minutes, the victim may lose consciousness, after which he has practically no chance of salvation.

Therefore, in every house, smoke-free stairwells are necessarily equipped as the most important condition for saving residents during a fire. What are the types of smoke-free stairs and stairwells?

Staircase is an integral element of buildings

The staircase is an integral element of multi-storey buildings. There are ordinary structures that serve to communicate floors, as well as evacuation stairs, that is, non-smokeable.

The presence of the latter is the most important condition under which the evacuation of people in case of fire is ensured. For a number of buildings, it is dictated by SNIP, therefore, architects must necessarily provide for when creating a structure project.

Evacuation ladders: purpose

Evacuation stairs must certainly be present in high-rise buildings. Such structures ensure the safety of residents during a fire or in case of other emergencies.

The arrangement of evacuation stairs in various types of buildings is subject to certain standards regarding their size, configuration and placement.

Regardless of the type of model, the general purpose of these structures is to ensure the safe exit of people from the building if necessary.

Residents of the building, employees and visitors of the institution, using evacuation stairs, can leave the premises without danger to life and health. The evacuation exit is designed to protect them from fire and smoke. It is very important to ensure free access to it for all those in the building.

Evacuation stairs can be used as an alternative exit from the premises. This is true for structures that are not equipped with a separate back door. Fire safety rules prohibit the operation of buildings above three floors that are not equipped with an evacuation staircase.

Location

Separate requirements apply to the location of evacuation stairs. Usually their placement is designed in the back of public buildings or from the end, if an open exit is planned.

With the proposed arrangement of an emergency exit inside the building, a separate room or corridor is allocated for such a staircase. This is necessary in order to ensure the safety of descending people in the event of a fire and to prevent blocking the often only possible exit from the house.

Such a room must be equipped with a fire-resistant door capable of containing the flame for at least 1 hour. At the same time, it is important to ensure the sealing of the joints and the rapid removal of smoke.

Each floor must be equipped with an exit to the stairwell. Its width depends on the size of the passage and steps. Semi-closed models provide for the location within the premises of the site, the door from which leads to an external staircase. This is an excellent option for cases where it is not possible to completely isolate the passage from smoke.

For open outdoor types, a special rule applies: the distance from the edge of the stairs to the wall must be at least 100 cm. This reduces the risk of fire entering the emergency exit and prevents the structure from heating up, as well as the protective handrails.

materials

Since this design is intended for use in extreme situations, including fires, the choice of materials used for its construction is determined by certain requirements. The main condition is to ensure the strength and fire resistance of the stairs. Therefore, the most popular materials are concrete and metal.

The use of materials that flammable, crumble or release toxic substances when heated is strictly prohibited.

SNIP and GOST requirements

GOST and SNiP standards regulate the norms by which all types of stairs are installed. They also apply to evacuation models.

• The standard slope of the evacuation stairs is such that the ratio of the length and height of the span is 2:1.
• For 1 march, 3-18 steps are allowed. For 2 marchers, their number should not exceed 16 pieces.
• The width of the tread should serve to ensure the comfort of movement, the optimal size is 24-29 cm.
• The step height is usually 20-22 cm.
• The width of the stairs is provided by the requirements such that 2 people can pass along it at the same time. The smallest allowable value is - 1 m. It is allowed to reduce the dimensions for external structures to 70 cm.
• The area between the marches should correspond in size to the width of the stairs and the exit to it.
• To ensure the safety of evacuation from the building in case of fire, it is necessary to provide an exit to the stairs, which leads to an open space or to a separate room, protected from fire and smoke.

Classification

Evacuation ladders are classified according to the type of material, location, and design features. There are three main types of modern evacuation stairs, which differ in such characteristics as purpose, width and configuration:

• placed on special smoke-free staircases inside the building;
• is located inside the building, and is not enclosed by walls;
• located outside and is an emergency exit design.

The latter is used exclusively for evacuation, while the first two types of stairs sometimes replace the main entrance.

About admissible types of constructions

For evacuation, direct marches are also used, equipped with intermediate platforms. In some cases, when there is not enough space for their location, vertical structures like firefighters are installed parallel or with a slight slope to the wall.

Strictly prohibited

Fire safety rules prohibit the construction of stairs:

• with winder steps;
• with curvilinear and irregular spans;
• screw;
• with steps of different sizes.

What are smoke-free stairwells?

The presence of such structures in the house is designed to ensure maximum safety of life and health of people in case of fire. They are marches of certain sizes, which should be located in the areas of the structure suitable for them.

One of the main requirements for an emergency exit is its isolation from smoke. Smoke-free stairwells are distinguished by the fact that during a fire, OFP (fumes, smoke, etc.) do not get into them.

The presence of these structures ensures successful evacuation of people in multi-storey buildings in case of fire. Different requirements are placed on them depending on the particular type.

Types

Smoke-free staircases are divided into several types, which can be classified by their specific design features, location, access to them and principles of operation. Types of stairwells:

• H1 is considered the base model. Characteristic features of the design is the availability of access using an open area. It is necessary to have a smoke-free approach to the emergency exit.
• H2 provides for the presence of air pressure in the event of a fire.
• H3 is an analogue of H2, but provides for access to the march through the vestibule-gateway. Additional air support is also provided, which is supplied both in case of ignition and on a permanent basis.

Requirements

Fire safety in stairwells is ensured by the rules that provide for the safety of human life:

• Emergency lighting is installed in all smoke-free stairs.
• The width of the doorway should be from 1.2 m, and the height - from 1.9 m.
• The width of the exits from flights of stairs should not be narrower than the width of the span.
• When installing a smoke-free cage adjacent to the elevator shaft, a ventilation hole is arranged in the wall to ensure free air access (at the level of the upper floor).
• It is forbidden to place personal belongings in the passages to smoke-free stairwells. The landing should be uncluttered, as rubbish can interfere with the evacuation of people and the work of firefighters.
• It is forbidden to independently install partitions not provided for by the construction project, as well as cutting passages in existing fire bulkheads.
• It is mandatory to equip smoke-free flights of stairs with handrails made of non-combustible and slightly heated materials.

Smoke-free stairs H1

"Building norms and rules" state: in buildings whose height is more than 30 m, smoke-free staircases of type H1 must be arranged.

This view requires the installation of ladders that can be accessed from the landing of the floor, using open air space to move. The location of H1 can be a veranda, a balcony or a fenced landing, taken out of the room.

This is due to the need to provide natural isolation from the smoky part of the building of the emergency exit. The best option for placing this type of staircase is the corner part of the building. The most advantageous position is the inner corner, equipped with additional piers.

Their design feature is the absence of a direct connection with the floors of the building.

The usual placement of H1 cells is in the corners of buildings on the windward side. They are characterized by the presence of transitions of a balcony type, as well as fences with protective screens. The transition is carried out in the form of an open gallery or loggia, the width of the passage must be from 1.2 m. The width between the passages, as well as the gap from the wall to the window, must be at least 2 m.

Smoke-free stairs H2

Stairwell H2 is arranged in a building, the top floor of which is at a height of 28-50 m. In the cells H2, an air overpressure is created (the principle of furnace draft).

It can be permanent or open in the event of a fire alarm.

It is also possible to install an autonomous backwater using electric air pumps that provide air pressure, which must be equipped with uninterruptible power supplies.

When designing ventilation, it is necessary to correctly calculate the traction force (or backwater). The pressure should allow the fire doors to open freely to the stairs. The pressure on the lower floor should be at least 20 pascals, on the upper floor - no more than 150 pascals.

The vestibules or gateways through which the entrance to the H2 stairwells is provided are equipped with fire doors. In smoke-free cages of this category, it is advisable to install vertical partitions with an interval of 7-8 floors.

Smoke-free stairs H3

Smoke-free staircase H3 is also built using air overpressure. Their difference lies in the arrangement of special walk-through rooms with self-closing doors. Their dimensions must be at least 4 square meters. m.

In cells of this type, air is pressurized into the space occupied by the stairs and into special locks. Air draft is carried out on a permanent basis or turns on automatically in case of fire or smoke.

Basic materials

When creating evacuation smoke-free passages, concrete is most often used. It is a fire-safe, durable and easy-to-use material. As an addition to the concrete base, steel structures are used, for example, in the manufacture of fences or doors. Metal spans are also justified in light construction structures.

Wooden elements are used in a small volume: wooden handrails or door handles, which must be treated with fire-fighting compounds.

Modern high-rise buildings require emergency exits, called smoke-free stairwells.

This type of evacuation must be provided by the architect during the development of the building itself. The life of people living in high-rise buildings largely depends on its presence.

An important condition is that smoke-free stairs must comply with the requirements of SNiP, otherwise their presence will be considered as an additional exit, not an evacuation one.

Why do we need non-smoke type staircases?

The need for houses with a large number of floors of a staircase that is not prone to smoke is due to the following factors:

• Prevention of death of people during the fire of the structure;
• The possibility of free penetration of employees of the fire organization to the source of ignition;
• Protection of people during the evacuation period from the action of toxic substances contained in the smoke during a fire;
• Providing rescue services with access to any floor of the building in order to save human lives and the possibility of carrying out on stretchers the victims who are unable to move independently;
• The ability of each occupant of the building to descend from any upper floor to the lower one without harming their own health during the period of necessary evacuation.

There are many options for smoke-free stairwells, depending on this they must meet certain requirements.

Types of smoke-free staircases

Basically, all evacuation routes in multi-storey buildings are divided into three types depending on their location according to the principles of functioning and accessibility:

• Type H1 - access to the stairs is provided by getting into an open area. Exit paths must also be smoke-free;
• Typical stairwell H2 - this type assumes the presence of an air backwater, the opening of which is necessary in the presence of fire situations;
• Typical stairwell H3 - design and operation is similar to H2, the difference is that the air pressure can be used on an ongoing basis, and access to the stairs is through a vestibule - a gateway.

Stairwell type H1

Smoke-free staircase type H1 is mandatory in buildings with a height exceeding 30 meters.

Access to this staircase is through a corridor to an open area. It can be an unglazed veranda or a regular balcony, as well as any other area that has a special fence and is located outside the building.

The best option for the location of H1 stairs is the corner part of a high-rise building. This is interpreted by the need for an isolated exit from smoke. In addition, the door that leads to the open area must be made of fireproof material.

Stairwell type H2

This type of evacuation structure is required in buildings with a height of 28 to 50 meters.

A feature of this structure is that the structure itself is located inside the building. The walls where the smoke-free staircase is located must be made of fire-resistant material.

The door leading to the emergency exit is located directly in the building, so the presence of a ventilation duct is a prerequisite. It is due to his presence that the requirement for air pressure on the stairs is fulfilled.

Basic rules for the operation of smoke-free staircases

Regardless of what types of staircases in your house, the operating rules for all are the same:

• You can never block the passage to the emergency exit;
• It is necessary to monitor the presence of lighting of stairwells;
• Periodically check the operation of the ventilation duct (if the escape route belongs to class H2);
• It is important to monitor the relevance of the availability of information about the paths leading to the emergency exit;
• Evacuation passages should not contain any cable channels, except for those provided for by fire safety.

SNiP requirements for emergency exits

Not every staircase can be an emergency exit.

It must comply with the requirements of SNiP:

• The width of the emergency passage must be at least 1.2 m;
• Height not less than 1.90 m;
• The number of marches on the stairwell between floors should be no more than 15.

The main materials used in the manufacture of smoke-free stairwells

In order for the staircase to be truly fireproof, the material of its manufacture plays an important role.

The fact is that it must withstand high temperatures when in contact with fire.

The best options are concrete and metal.

The metal structures of the flights of stairs are very well suited for the construction of evacuation routes of the H1 type.

For type H2, it is best to use a concrete structure, since they are not only durable and comfortable, but also always comply with the requirements of SNiP.

There are cases when wood is used to build a smoke-free staircase, but in this case it must be impregnated with a special solution that prevents fire.

According to what characteristics are smoke-free exits checked by firefighters

It is important to know by what parameters the evacuation routes are checked.

When putting a multi-storey building into operation:

• Compliance with the main parameters;
• Inspection of the structural integrity of the structure;
• Evaluation of the quality of the protective coating;
• The presence of the integrity of the weld;
• Compliance with the requirements for the placement of a smoke-free stairwell;
• Testing the strength of the following structural elements: steps, beam fastenings, platforms, stair railings and roofs.

In addition, once every 5 years, the possibility of operating emergency exits is checked according to the following characteristics:

• Checking the integrity of the structure of the structure;
• No cracks in the welds;
• The quality of the protective coating;
• Integrity of the beam fastenings of the stairs;

Tested for strength:

1. steps;
2. Stair railings;
3. Venues;
4. Balcony railings.

All the above requirements for smoke-free staircases are important to know not only for architects and employees of construction companies, but also for the common man.

Two and three-story mansions should also be equipped with emergency exits.

1. When buying an apartment in a multi-storey building, do not forget to ask about the availability of evacuation routes;
2. Make sure they are in working order;
3. Conduct an exercise with all members of your family on the use of escape routes so that there is no panic at the moment of danger (especially if the H2 stairwell is used);
4. Make sure that the path to the smoke-free staircase is always open. In cases of its obstruction, contact the perpetrators with a request to remove the barrier.
5. Only the vigilant attitude of everyone living in a high-rise building can help save the lives of hundreds of people.

Various smoke-free staircases are now integral elements of modern multi-storey buildings. Why? Yes, because in the event of a sudden fire, they can become the only way to salvation. For structures of this kind, there is a special classification. And this article describes the features of types H1, H2, H3, which need to be considered in more detail.

The main purpose of all smoke-free cells

The above-mentioned stairwells are marches that have certain dimensions and are located in the most suitable areas for them in multi-storey buildings. Such structures should serve as emergency exits for people in specific buildings. First of all, we are talking about situations directly related to fires.

After all, significant smoke in the upper space of buildings is a consequence of any fires, regardless of their scale. And many people die in such situations not at all from the flame itself, but from the extremely negative influence of all kinds of toxic fumes and smoke. Therefore, emergency exits must be isolated from smoke.

However, that's not all. With the help of ladders, photos of which can be seen in the article, rescuers have the opportunity to get to the interior of the houses in order to quickly put out the fire and bring the injured residents out. These structures even allow people to be carried out on a stretcher in case of emergency.

Key varieties of unique designs

After watching videos located on different network resources, it becomes clear that all smoke-free cells are divided into three main types:

Standard requirements for such structures

Absolutely all smoke-free staircases must one hundred percent comply with certain mandatory requirements. Basically, they relate to both the dimensions of entire structures and the dimensions of the marches themselves:

1. The minimum height of the ceilings located in the march areas must be at least 190 cm. This is the only way for the average person to move along the evacuation routes quite comfortably.
2. Having studied the features of types H1, H2, H3, you can find out that the width of the passages in the so-called "air zones" should reach 120 cm. But the dimensions of the paths leading to them cannot be less than 110 cm, this is really extremely important. Indeed, in this way, completely unhindered movement of two people and the transfer of victims on special stretchers are ensured.
3. The steps of flights of stairs must have the same parameters. As for the slope, it usually does not exceed 40 degrees.
4. A maximum of 18 ordinary steps can be located on one march, this can be clearly seen in the photo below.

All kinds of fences made exclusively from non-combustible materials are considered mandatory elements of smoke-free structures. They allow not only to minimize the risk of injury to people, but also significantly facilitate movement.

Useful information about H1 cells

Various specialized videos perfectly demonstrate that in buildings with a height of about 30 m, high-quality class H1 smoke-free structures must be equipped. They are directly related to the floors of buildings. And the structures of a similar plan are located precisely in the corners of the houses (on the windward side).

These staircases are equipped with balcony-type transitions, which are protected by reliable protective screens. Their width cannot be less than 1.2 m. But the dimensions of the walls between such transitions must already reach 2 m.

What you need to know about class H2 structures?

It is noteworthy that non-smokeable staircases of type H2 are mainly equipped in buildings whose height is from 28 to 50 m. The list of their main features includes:

Although in such structures, autonomous air supports from electric pumps are sometimes equipped. These devices are equipped with uninterruptible power supplies. But for this, it is necessary to carefully calculate the traction force even when designing mandatory ventilation.

Arrangement of smoke-free structures of type H3

Having considered the main features of the types H1, H2, H3, it can be understood that the staircases of the third class are still different from other structures. They are complemented by special rooms designed for people to cross, in which self-closing doors are installed on innovative door closers. Their dimensions should be at least 4 square meters. meters, no less.

Separately, it is worth mentioning the air pressure. In such structures, it is carried out not only in the space occupied by the stairs, but also in the existing gateways. In addition, the backwater can be switched on automatically during fires or it can be supplied on an ongoing basis.

Materials used for the manufacture of staircases

Modern smoke-free structures, the photos of which are in this article, are created exclusively from materials that can resist heat well and not ignite in direct contact with fire. For example, concrete is one of them. It is absolutely fireproof, and marches made from it have increased strength.

Sometimes metals are also used for cells of this kind. However, these materials are used only in cases where it is simply not possible to build more massive structures. Craftsmen reinforce both the internal parts of concrete marches and the fences with metal elements. All this is perfectly visible on the video.

Why is it worth contacting our specialists?

In order for smoke-free staircases to perform their functions quite well, they must be made only from the highest quality materials in accordance with all the rules. Using the services of our specialists, customers can easily purchase very beautiful, most reliable, and most importantly, really durable structures in Moscow at the lowest prices.

Experienced craftsmen create such structures in accordance with generally accepted requirements and standards. In addition, they always take into account the wishes of customers during their work. That is why our designs today are wildly popular.