The fire resistance limit of building structures is measured in. What do the letters REI mean in the abbreviation for fire resistance

12.06.2019 Accessories

Often, fire doors and other structures are usually divided into classes according to fire protection parameters. In this case, the marking EI, EIWor EIS. What do these designations show? In what cases are they used?

Before buying and installing a fireproof door, double-glazed windows and other ceilings, it is important to familiarize yourself with the existing regulations regarding fire safety requirements in a particular building.

Mismatch installed door, windows, etc. the fire protection class required in a given room will serve as a reason for refusing to put the building into operation.

So in general view The EI fire safety class indicates the ability of a structure to withstand the onslaught of open fire in the event of a fire for a certain time.

There are also additional characters added to EI:

EIW- indicates that the heat will not penetrate outside the room through radiation. This marking is relevant only for glazed structures;

EIS- and this is a generally accepted marking for doors with an air duct ventilation grill.

The fire resistance class is assigned on the basis of tests carried out on the product in a special fire chamber. If the test is completed successfully, the company receives the appropriate certificate.

Fire resistance limit EI 60

EI 60 fire resistance limitis the most commonly used type. It can be said that this is optimal combination in terms of value for money.

At the same time, a door, window or ceiling corresponding to this class must last at least 60 minutes (one hour) without loss of structural integrity and prevent the spread of fire, combustion products, and high temperatures outside the room limited by the door.

Fire resistance limit EI 45

EI 45 fire resistance limit, respectively, will ensure that an open flame, combustion products, as well as thermal energy will not spread throughout the building for at least 45 minutes.

Structures with such a fire resistance limit can be installed in places with high traffic, on landings, in office and industrial buildings. In a word, wherever 45 minutes should be enough for the complete and safe evacuation of residents or working personnel.

EI 45 fire resistance limitapplies not only to doors, but also to glazed coverings, including windows and partitions.

Fire resistance limit EI 30

One of the most affordable price options is EI 30 protection class. By this is meant the ability of the structure to resist the spread of flame for half an hour - that is, at least 30 minutes.

Since the presence of an influx of oxygen mainly contributes to the spread of fire, such doors provide tightness during a fire. Thanks to this, neither smoke nor elevated temperatures pass outside.

An additional advantage of doors and double-glazed windows with any degree of resistance EI, including EI 60, can be considered their excellent noise and heat insulation characteristics.

EI 60 doors can be ordered both in a “warm” version and in a “cold” version, that is, designed for installation indoors or in an entrance group.

Fire resistance limit EI 150

Then, as, for example,EI 60 fire resistance limitis standard, the manufacturer can offer non-standard refractory systems. This includes, for example, designs EI 20, EI 100, and 150.

Usually in this case we are talking about the manufacture of products to order according to the individual requirements of the customer.

Often, the thickness of both the working material and the fire-resistant outer coating increases.

However, the principle remains the same: EI 150 allows you to keep the spread of open fire and high temperatures for 150 minutes. They resort to such high fire protection in crowded places and in many hazardous industries.

Fire resistance limit of building structures

In order to give an approximate estimate of the fire resistance limit of specific structures, during their development and design, the following points should be followed:

The fire resistance threshold of layered fences in terms of thermal insulation ability is comparable, and, in most cases, exceeds the totality of the stability limits of individual layers. This indicates that a larger number of layers of the building envelope does not reduce fire resistance. In some cases, additional layers may not play a significant role, for example, cladding made of sheet metal from the side that is not heated;

Enclosing structures with air layer, on average 10% higher in fire resistance than analogues without it. At the same time, its efficiency increases in proportion to the distance from the heating source, regardless of the thickness;

Unsymmetrical arrangement of layers affects the fire resistance depending on the direction heat flow. In the most fire hazardous place, it is recommended to place fireproof materials with low thermal conductivity;

Increased humidity of structures slows down heating, increases fire resistance, except for those cases when, with increasing humidity, the material becomes more brittle (which is especially important for products made of concrete or asbestos cement);

Fire resistance decreases at high loads - structures with the most stressed section serve as an indicator for determining the fire resistance limit;

The period of exposure to heat also affects the ability of a material to withstand high temperatures in a fire;

Structures whose heat resistance cannot be determined usually have a higher heat resistance limit of similar statically determinate structures. It is also important to take into account the additional forces resulting from thermal deformations;

The fire resistance of a structure does not depend on the flammability of the materials of which it is composed. Yes, thin metal profiles have a minimum fire resistance limit, while wooden structures have a higher rate with the same ratio of the heated perimeter of the section to the area and impact force, tensile strength or yield strength.

Attention! Combustible materials used in the design of a building, instead of slow-burning or non-combustible ones, can greatly reduce the fire resistance of the entire structure. This is especially true when the burnout rate exceeds the warm-up rate.

Methods for improving fire safety

To increase the resistance of structures to high temperatures and bring it to the specified parameters, during construction, different kind fire retardant materials. They allow you to block the surface of the protected structure from the thermal effect and keep it in working condition for a certain period of time.

Fire retardant coatings are used for:

building structures, which include columns, frames, trusses, blocks, slabs and floors;

air ducts and gas ducts with relevant safety requirements;

cabling, penetration through fire-resistant fences;

containers with oil products, flammable and combustible liquids;

plasters, concrete or brick finishes - relevant for structures designed for additional loads.

For these purposes, special facing plates are used, protective screens, surface coating with flame retardants, impregnation wooden structures chemicals.

Systems that increase the limits of fire resistance are various types and consist of different materials. The most commonly used: heat-resistant fillers (vermiculite, expanded clay, basalt, etc.), inorganic-based binders (gypsum, cement), polymers that increase the overall resistance and strength of structural elements. The above systems can be used both independently and be combined.

Upon contact with high temperature the organic components of the binder coating swell, simultaneously forming foam coke. Thus, the material burns out slowly, while the structure remains functional for a long time. long time. Mineral coatings block heat flow by releasing a large number steam, because they contain bound water. Due to this, the temperature rises gradually, and the structure is not destroyed so intensively.

Fire-resistant sandwich panels are divided into two types depending on their ability to withstand fire.

structures of the first type. Barriers with a maximum fire resistance limit (REI 150 walls), where "150" indicates the time (in minutes) during which the barrier is able to maintain its fireproof properties, "R" is the loss of bearing capacity, "E" is the loss of integrity, and " I" - loss of heat-insulating ability of the structure.
structures of the second type. The limit of fire resistance of barriers is more than REI 45.

Fire-resistant panels are usually divided into three main groups: fire walls (firewalls), partitions and ceilings. The construction of fire-resistant walls, partitions and ceilings is one of the most effective ways safety of buildings from fires.

Partitions

Fire partitions are vertical enclosing structures that separate rooms within one floor. They are able to delay the spread of fire within no more than one floor. Partitions must be installed in places of possible accumulation of explosive mixtures. They are also installed in niches for communications, basements and warehouses, elevator shafts and channels to reduce possible damage in case of fire. Fire barriers of the 2nd type, compared to other groups of fire barriers made of sandwich panels, have the lowest fire resistance index - they are able to withstand the spread of fire from 15 to 45 minutes. Fire doors, gates, windows and valves should be provided to fill openings.

firewall walls

The firewall wall is installed vertically between buildings along the entire height, crossing all structures and floors of the building. It rests on foundations or foundation beams and retains fire resistance even in the event of a one-sided collapse of structures adjacent to them. It is installed to divide the building into compartments (parts of the building separated by walls). The compartments, in turn, are separated by other fire-resistant barriers. Fire walls of the 1st type can be equipped with fire locks, when they are installed, it is unacceptable to use other types of filling openings. When erecting type 2 fire walls, fire doors, gates, windows and valves should be provided. This type of barrier retains heat-insulating properties for at least 2.5 hours.

Overlappings

A fire barrier is a barrier whose main purpose is to limit the spread of fire from one floor to another. It is possible to equip fireproof ceilings of the 1st type with fire locks, in their device it is unacceptable to use other types of filling openings. Overlappings are divided into 4 types, depending on the time during which they can resist the spread of fire:

the first can protect the building from the spread of fire within 2.5 hours;
the second - within 1 hour;
the third will keep the spread of the flame for no more than 45 minutes;
the fourth - for 15 minutes.

Fireproof partitions, firewall walls and ceilings from the manufacturer, the Teplant company, are considered one of the most reliable options for supporting fire protection buildings for various purposes. They meet all requirements for structures. regulatory requirements, are characterized high quality, ease and practicality during assembly.

Fire barriers	Type of fire barriers	Fire resistance limit fire barrier, min.	Type of filling openings, not below	Gateway type, not lower
	1	REI 150	-	1
	2	REI 45	2	2
Partitions	1	EI45	2	2
Partitions	2	EI 15	3	3
Overlappings	1	REI 150	-	1
	2	RE 60	2	1
	3	RE 45	2	2
	4	RE 15	3	3

it special kind enclosing fire systems that serve to fill openings in fire barriers of various building structures (buildings and structures). Their main task is to contain the spread of fire and combustion products in a fire.

It should be noted that from the point of view normative documents PD is also understood as fire doors, hatches, valves, windows, curtains and curtains, so hereinafter we will use the general term "fire doors" or "PD".

Except when it comes to a specific type of structures (gates, hatches, windows, etc.) for filling openings in fire barriers.

Technical characteristics of PD are classified according to the following main features:

Fire resistance limits - E, EI, EIW, EIS, EIWS

This is the period of time (indicated in minutes or hours) from the moment the flame begins to affect the surface, until the onset of one or more limit states.

The fire resistance limit of PD is determined during fire resistance tests in accordance with GOST.

Basic limit states of PD:

E - loss of door integrity, and / or
I - heat-insulating ability.

Other types of limit states include:

W - achievement of the limiting value of the heat flux density - for glazed PDs with a glazing area of more than 25% of the sheet area, and
S - achievement of the limiting value of smoke and gas tightness - for smoke and gas tight PDs with a glazing area of more and less than 25% of the leaf area.

The fire resistance limit of refractory structures is measured in minutes - 15, 30, 60, etc. minutes and is designated as EI-15, EI-30, EI-60 respectively. The fire resistance limit of fire windows is indicated only by the loss of integrity (E), i.e. E-15, E-30, E-60.

In the course of testing structures for fire resistance, the smallest value of the onset of the limit state is taken.

So if the design during the tests lost its heat-insulating ability (I) at the 35th minute, and integrity (E) at the 65th, then the product will be assigned a fire resistance limit of EI-30.

It is also important that the fire resistance indicators should be read as - “not less than (15, 30, 45, 60) minutes”, that is, a design with a fire resistance limit of EI-60 can contain fire for more than 60 minutes, but less - nothing can not.

Types and classes of PD

According to table No. 24, Federal Law 123, there are three types, each of which corresponds to one or another fire resistance limit:

PD type 1 corresponds to the fire resistance limit EI-60 (60 minutes);
PD type 2 corresponds to the fire resistance limit EI-30 (30 minutes);
PD type 3 corresponds to the fire resistance limit EI-15 (15 minutes).

Web materials

It refers to the material of which the fabric of the structure consists.
According to the type of material, the following types of PD are distinguished:

- the canvas, as well as the frame of such doors, are usually made of steel with a thickness of 1 mm or more, hence their other name - steel (iron) fire doors;
– the sheet consists of specially treated wood and/or wood-based refractory materials. The box can be either metal or wooden;
Glazed - metal or wooden PD with glazing less than 25% of the door leaf area;
and partitions - the door leaf of such structures is more than 25% made of translucent material, as a rule, it is fire-resistant glass or fire-resistant glass with a gel-like non-combustible filling. The frame and frame of the leaf of such doors most often consist of aluminum.

There is a myth that there are plastic PDs, but this is nothing more than fiction. Although the fire door can be finished with plastic (especially for wooden fire doors), there are no technologies for manufacturing a plastic fire door yet.

This is due to the fact that PVC products, in principle, cannot withstand prolonged exposure to fire - plastic not only has very low refractory properties, but also extremely toxic when burned, which is unacceptable for this type of structure.

Where are PDs installed?

These places are strictly regulated by regulatory documents. In general, the following main places where PDs are installed can be distinguished:

In crowded places - shopping and business centers, cinemas, hotel complexes, hospitals, schools, libraries, museums, etc.;
Technical rooms, as well as rooms with electrical, gas and other fire hazardous equipment - switchboard, industrial premises, boiler rooms, warehouses (especially warehouses with flammable and explosive substances), kitchens of canteens and restaurants, etc.;
On the ways of evacuating people from the building (premises) - exits to evacuation stairs, exits from elevator halls, emergency and fire exits.

Design features

There are the following design features refractory structures:

Number of door panels

There are two main types:

Single floor (in technical documentation, as a rule, are not indicated at all or are indicated by the number 1);
Double-field (indicated by the number "2", for example G2 - deaf double-field right).

In another way, such doors are called single-leaf and double-leaf, respectively.

In turn, double-sided fire doors are divided into equal-sided ones - when both door leaves the same size and multi-field - when the door leaves are of different sizes.

Distinguish between active and passive doors. The active leaf is the one on which the handle for opening and closing is located, the passive leaf is without a handle. The active sash can be either right or left;

Orientation of opening

Fire doors, like any others, can be right (in the technical documentation, as a rule, they are not indicated) or left (indicated - “L”, for example, the GL door is a deaf single-leaf left door).

Often the direction of the door is mistakenly determined by the opening side - if the door opens to the left, then it is left-handed.

This is not so, in fact, the side of the door is determined by the outer door hinges from the side of the active sash.

Those. if you stand facing the door so that door hinges of the active sash are on the outside (or on the side closest to you) door frame if the hinges are hidden), and if they are on the right, then the door is right, if the hinges are on the left, then the door is left;

door leaf type

There are two main types:

Deaf cloth - in the technical documentation it is designated - "G", for example GL - deaf single-field left;
Glazed canvas - denoted - "C", for example S2L - glazed double-left, otherwise glazed fire doors are called translucent.

When choosing a fire door, it is important to remember the following:

Installation and assembly

Can only be carried out by an organization licensed to this species works.

If you do not have a license for the right to install fire doors, it is strictly forbidden to install such doors on your own. Responsibility for such a violation can be very serious, up to criminal.

When buying, you need to check with the seller whether he has a license to install doors.

If the seller is not engaged in installation, you will have to look for a third-party organization (the one that has a license for this type of work), which means you will have to spend your time and money searching for a licensed installer.

Certification of fire-resistant structures

Actually, only those doors that have passed fire resistance tests, according to the results of which a certificate is issued, can be called fireproof.

In other words, the PD certificate is a guarantee that the doors you bought are really fireproof. And this means that in a fire they will help save people's lives, material values and property.

Passport for the product

It is important to remember that a certificate of conformity and a fire door passport are two different things.

The passport for a specific product for each manufacturer may be different in content, volume, etc., while the certificate has one strictly established form.

A passport without a certificate of conformity is not valid, and such a door cannot be called fireproof.

Cost and approximate prices

When buying PD, you need to be guided by the rule - "the more and better - the more expensive."

That is, the larger the area door leaf and glazing, the better and more expensive Decoration Materials and fittings, the more additional equipment installed on the canvas (fenders, transoms, ventilation grates etc.) - the more the price will increase significantly.

Remember!

If the door is called a fire door, it means that similar designs of a particular manufacturer have been tested for fire resistance.

And this means that this type of construction complies with the requirements of GOST and they must have a certificate of conformity, and in any case, they are required to contain the fire for the declared time.

That is, a PD for 10 thousand rubles will contain fire in the same way as the door that costs 20 thousand rubles - this is a fact. And if the seller assures you otherwise, this is nothing more than a marketing ploy.

The thing is that an expensive door will most likely look more expensive and more elegant. And what kind of fire-resistant design is needed for your specific situation - it's up to you.

In everyday life, the consumer does not need to be interested in the fire resistance characteristics of equipment and premises. Most of the citizens live with the installation of a safe life, so the indicators fire resistance and the availability of fire fighting equipment are of interest exclusively to specialists in this field.

Understand the basic concepts of fire safety to all citizens, because it can save health and even life. I propose to consider the common abbreviations for fire safety levels and the classification of the degrees of fire hazard and the factors that determine them.

What does REI mean?

The abbreviation can be found on the packaging some building materials and in buildings (often on signs near fire extinguishers). Interpretations differ somewhat among themselves, but we will consider those listed in building codes and rules (SNIP). The Latin letters REI are interpreted as follows:

"R" indicates for loss of bearing capacity, in other words, it is the stability of the building/material during a fire. The loss of bearing capacity simultaneously characterizes the weakening of the level of thermal insulation and the integrity of the structure.

The indicator is checked as follows: element of a building or equipment amenable to fire treatment. The expert visually determines how long the material reaches its ultimate strain. The time is indicated in minutes.

The stability index is calculated not only in the field of fire safety. This concept is used for corrosion, pressure and other factors that can change the design of the object. It turns out that the bearing capacity indicator indicates the permissible load level.

"E" is characterized as loss of integrity. Experts determine the period of fire exposure, after which through cracks and holes form on the material. For example, if the designation “60EI” is indicated on the object, this means that with a fire treatment of 180%, the material begins to crack after 60 minutes.

The digital indicator always indicates the time, and the alphabetic indicator always indicates the criterion being checked and the temperature.

"I" - Latin index, characterizing thermal insulation properties designs. It is also referred to as the extreme flash point. The index characterizes the time interval after which the nearby objects heat up to the limit level.

This kind of objects are not amenable to fire directly. Often this occurs after the loss of integrity, when fire and combustion objects penetrate through cracks in heated equipment.

What is fire resistance and how is it determined?

Fire resistance is general characteristicsfire safety of the facility. If we are talking about a building, this level is determined on the basis of fire safety indicators. individual elements the buildings.

It should be borne in mind that the real level will always be slightly lower than the specified one, because the room does not consist of only walls. Wallpaper, accessories, household items significantly raise the level of fire risk.

Fire classification

First of all, it is divided into actual and required. The required indicator is displayed in the SNiP in the section " fire safety buildings and structures". When the structure of the building reaches a certain level, a group of experts checks the actual level, i.e. the actual one.

If it is lower than required, permission for further construction not issued. Each type of object has its own acceptable fire safety level.

It is determined by the degree of fire resistance. There are 5 of them in total. The first degree of REI 120, and the fourth - REI 45 - these are the acceptable levels for inside walls of living quarters. The same degrees for car windows will be somewhat lower. Aisles for the criteria of the fifth degree are not indicated.

What forms the fire resistance index?

The index is mainly affected by the elements that make up the equipment or structure. First of all, objects are defined as combustible or non-combustible. Equipment item classify in the following way:

non-flammable - K0;
low fire risk - K1;
moderately flammable - K2;
fire hazardous - K3.

The regulatory acts "Fire safety of buildings and structures" detail the characteristics of materials.

Buildings are classified in a similar way, their performance depends on the above levels of fire hazard of the elements. The indexes for structures are as follows:

C0 - if the level of elements used in the process of building does not exceed K0;
C1 - when the main indicators are K0, K1. K2 is allowed for external walls;
C2 - the maximum fire hazard indicator - K3 (allowed for external and load-bearing walls);
C3 - carriers, external walls, non-attic coatings are not standardized. Wall limit staircase and fire barrier - K1, for the landing of stairs - K3.