Critical surface heat flux density GOST. Building materials

Heat flux, W / m

Material	Irradiation duration, min

Rough wood
Wood painted with oil paint
Briquette peat
Lump peat
Cotton-fiber
Gray cardboard
Fiberglass
Rubber
Combustible gases and flammable liquids with autoignition temperature, ° С:




>500	-	-
A person without special protective equipment:
for a long time;		-	-
within 20 s		-	-

Comparison of the Q lcr values obtained by calculation using the formula with the data from the table will make it possible to draw a conclusion about the possibility of ignition in a given time or to determine safe distances from the fire source for a given exposure time.

Neutralization and elimination of ignition sources;

Increasing the fire resistance of buildings and structures;

Organization of fire protection.

The engineering and technical measures for fire protection include:

Application of the main building structures of objects with regulated fire resistance and fire hazard limits;

The use of impregnation of structures of objects with antipenes and the application of fire retardant paints (compositions) on them;

The use of devices that limit the spread of fire (fire barriers; maximum permissible areas of fire compartments and sections, limitation of number of storeys);

Emergency shutdown and switching of installations and communications;

The use of means to prevent or restrict the spill and spread of liquid in the event of a fire;

Use of flame retardants in equipment;

Use of fire extinguishing equipment and related types of fire fighting equipment;

Use of automatic fire alarm systems.

The main types of equipment designed to protect various objects from fires include signaling and fire extinguishing equipment.

A fire alarm must communicate a fire quickly and accurately. The most reliable fire alarm system is the electrical fire alarm. The most advanced types of such alarms additionally provide automatic activation of the fire extinguishing means provided at the facility. A schematic diagram of the electrical alarm system is shown in Fig. 14.1. It includes fire detectors installed in the protected premises and included in the signal line; receiving and control station, power source, sound and light alarm means, and also transmits a signal to automatic fire extinguishing and smoke removal systems.

The reliability of the electrical signaling system is ensured by the fact that all its elements and connections between them are constantly energized, which ensures control over the serviceability of the installation.

The most important element of a fire extinguishing system is fire detectors, which convert the physical parameters that characterize a fire into electrical signals. According to the method of activation, the detectors are divided into manual and automatic. Manual call points send an electrical signal of a certain shape to the communication line at the moment the button is pressed. Automatic fire detectors turn on when the environmental parameters change at the time of the fire. Depending on the factor that triggers the sensor, the detectors are divided into heat, smoke, light and combined.

The most widespread are heat detectors, the sensitive elements of which can be bimetallic, thermocouple, semiconductor.

Smoke fire detectors that react to smoke have a photocell or ionization chambers as a sensitive element, as well as a differential light relay. Smoke detectors are of two types: point, signaling the appearance of smoke in the place of their installation, and linear-volumetric, operating on the principle of shading the light beam between the receiver and the emitter.

Light fire detectors are based on fixing various components of the open flame spectrum. Sensing elements of such sensors respond to the ultraviolet or infrared region of the optical radiation spectrum.

The inertia of the sensors is an important characteristic. Thermal sensors have the highest inertia, and light sensors have the lowest.

Firefighting. A set of measures aimed at eliminating a fire and creating conditions under which the continuation of combustion will be impossible is called fire extinguishing.

To eliminate the combustion process, it is necessary to stop supplying either fuel or oxidizer to the combustion zone, or to reduce the supply of heat flow to the reaction zone. This is achieved:

Strong cooling of the combustion center or burning material with the help of substances (for example, water) with a high heat capacity;

Isolation of the combustion center from atmospheric air or by reducing the concentration of oxygen in the air by supplying inert components to the combustion zone;

The use of special chemicals that inhibit the rate of the oxidation reaction;

Mechanical breakdown of the flame by a strong jet of gas or water;

Creation of fire protection conditions in which the flame spreads through narrow channels, the cross-section of which is less than the extinguishing diameter.

Fire extinguishing agents. Currently, the following are used as fire extinguishing agents:

Water that is supplied to the hearth of a fire with a continuous or spray jet;

Various types of foams (chemical and air-mechanical), which are air or carbon dioxide bubbles surrounded by a thin film of water;

Inert gas diluents, which can be used as: carbon dioxide, nitrogen, argon, water vapor, flue gases, etc .;

Homogeneous inhibitors - low-boiling halogenated hydrocarbons;

Heterogeneous inhibitors - fire extinguishing powders;

Combined formulations.

The most widespread fire extinguishing agents are given in table. 14.4.

Table 14.4

Extinguishing agents

Extinguishing agent	Method and effect on combustion
Water, water with a wetting agent, solid carbon dioxide (carbon dioxide in the form of a snow), aqueous solutions of salts	Cooling
Fire extinguishing foams (chemical, air-mechanical); fire extinguishing powder compositions; non-combustible bulk substances (sand, earth, slags, fluxes, graphite); sheet materials (bedspreads, shields)	Insulation
Inert gases (carbon dioxide, nitrogen, argon, flue gases); water vapor; water mist; gas-water mixtures; explosion products of explosives; volatile inhibitors from the decomposition of halocarbons	Dilution
Halocarbons; ethyl bromide, freon 114 B2 (tetrafluorodibromoethane) and 13 B1 (trifluoro-bromomethane); halocarbon-based formulations: 3.5; NND; 7; BM; BF-1; BF-2; water-bromoethyl solutions (emulsions), fire extinguishing powder compositions	Inhibitory effect. Chemical inhibition of the combustion reaction

Water is the most widely used extinguishing agent. However, it is also characterized by negative properties:

Electrically conductive;

It has a high density and therefore is not used for extinguishing oil products;

Able to react with certain substances and react violently with them (potassium, calcium, sodium, hydrides of alkali and alkaline earth metals, saltpeter, sulfur dioxide, nitroglycerin);

Has a low utilization rate in the form of compact jets;

It has a high freezing point, which makes it difficult to extinguish in winter, and a high surface tension - 72.8-10 3 J / m 2, which is an indicator of the low wetting ability of water.

Water with a wetting agent (addition of a foaming agent, sulpanol, emulsifiers, etc.) can significantly reduce the surface tension of water (up to Z6.410 3 J / m 2). In this form, it has good penetrating ability, due to which the greatest effect is achieved in extinguishing fires, and especially when burning fibrous materials: peat, soot. Aqueous solutions of wetting agents can reduce water consumption by 30-50%, as well as the duration of extinguishing a fire.

Water vapor has a low extinguishing efficiency, therefore it is used to protect closed technological devices and rooms with a volume of up to 500 m 3, to extinguish small fires in open areas and create curtains around protected objects.

Finely sprayed water (droplet size less than 100 microns) is obtained using special equipment operating at a pressure of 200-300 mm of water. Art. Water jets have a small impact force and flight range, but they irrigate a significant surface, are more favorable for water evaporation, have an increased cooling effect, and dilute the combustible medium well. They allow not to moisturize unnecessarily the materials when they are extinguished, contribute to a rapid decrease in temperature, the deposition of smoke or poisonous clouds. Water mist is used not only for extinguishing burning solid materials and oil products, but also for protective actions.

Solid hydrocarbon dioxide (carbon dioxide in a snow-like form) is 1.53 times heavier than air, odorless, density 1.97 kg / m 3. Solid carbon dioxide has a wide range of applications, namely: when extinguishing burning electrical installations, engines, in case of fires in archives, museums, exhibitions and other places with special values. When heated, it passes into a gaseous substance, bypassing the liquid phase, which makes it possible to use it for extinguishing materials that deteriorate when wetted (from 1 kg of carbon dioxide, 500 liters of gas are formed). Non-conductive, does not interact with combustible substances and materials.

It is not used to extinguish ignited magnesium and its alloys, metallic sodium, as this decomposes carbon dioxide with the release of atomic oxygen.

Chemical foam is now mainly produced in fire extinguishers by the interaction of alkaline and acidic solutions. Consists of carbon dioxide (80% vol), water (19.7%), foaming agent (0.3%). The characteristics of the foam that determine its fire-extinguishing properties are durability and multiplicity. Durability is the ability of the foam to remain at a high temperature over time (air-mechanical foam has a durability of 30-45 minutes), the ratio is the ratio of the volume of the foam to the volume of the liquid from which it is obtained, reaches 8-12. Chemical foam is highly resistant and effective in extinguishing many fires. Due to its electrical conductivity and chemical activity, foam is not used to extinguish electrical and radio installations, electronic equipment, engines for various purposes, and other devices and assemblies.

Air-mechanical foam is obtained by mixing an aqueous solution of a foaming agent with air in foam shafts or generators. Foam can be of low expansion (K< 10), средней (10 < К < 200) и высокой (К >200). It possesses the necessary stability, dispersion, viscosity, cooling and insulating properties, which make it possible to use it to extinguish solid materials, liquid substances and to carry out protective actions, to extinguish fires on the surface and to bulk fill burning rooms. Air-foam barrels are used to supply low expansion foam, and generators are used to supply medium and high expansion foam.

Fire extinguishing powder compositions are versatile and effective means of extinguishing fires at relatively low specific costs. OPS is used to extinguish combustible materials and substances of any state of aggregation, electrical installations under voltage, metals, including organometallic and other pyrophoric compounds that cannot be extinguished with water and foam, as well as fires at significant subzero temperatures. They are able to provide effective action to suppress the flame in combination; cooling (removal of heat), insulation (due to the formation of a film during melting), dilution with gaseous decomposition products of a powder or a powder cloud, chemical inhibition of the combustion reaction.

Nitrogen is non-flammable and does not support the combustion of most organic substances. It is stored and transported in cylinders in a compressed state, used mainly in stationary installations. They are used to extinguish sodium, potassium, beryllium, calcium and other metals that burn in an atmosphere of carbon dioxide, as well as fires in technological devices and electrical installations. Nitrogen should not be used to extinguish magnesium, aluminum, lithium, zirconium and some other metals that can form nitrides, have explosive properties and are sensitive to impact. Argon is used to extinguish them.

Halocarbons and compounds based on them (extinguishing agents for chemical inhibition of the combustion reaction) effectively suppress the combustion of gaseous, liquid, solid combustible substances and materials in all types of fires. In terms of efficiency, they exceed inert gases by 10 times or more. Halocarbons and compounds based on them are volatile compounds, they are gases or volatile liquids that are poorly soluble in water, but mix well with many organic substances. They have good wetting properties, are not electrically conductive, and have a high density in liquid and gaseous state, which allows the formation of a jet that penetrates into the flame.

These extinguishing agents can be used for surface, volumetric and local fire extinguishing. Halo-hydrocarbons and compositions based on them can be practically used at any negative temperatures. They can be used with great effect to eliminate the combustion of fibrous materials; electrical installations and equipment under voltage; to protect vehicles from fires; computing centers, highly hazardous workshops of chemical enterprises, painting chambers, dryers, warehouses with flammable liquids, archives, museum halls, and other objects of special value, increased fire and explosion hazard.

The disadvantages of these extinguishing agents are: corrosiveness; toxicity; they cannot be used to extinguish materials containing oxygen, as well as metals, some metal hydrides and many organometallic compounds. Freons do not inhibit combustion even when other substances, rather than oxygen, are involved as an oxidizing agent.

Fire extinguishing equipment. The provision of enterprises and regions with the necessary volume of water for fire extinguishing is usually made from the general (city) water supply network or from fire reservoirs and tanks. Requirements for water supply systems are set out in SNiP 2.04.02-84 * “Water supply. External networks and structures "and in SNiP 2.04.01-85 *" Internal water supply and sewerage of buildings. "

Fire-fighting water pipelines are usually subdivided into low and medium pressure water pipelines. The pressure for fire extinguishing from the low-pressure water supply network at the design flow rate must be at least 10 m, while the water pressure required for fire extinguishing is created by mobile pumps installed on hydrants. In the high-pressure network, a compact jet height of at least 10 m must be ensured with the full design water flow and the location of the shaft at the level of the highest point of the tallest building. High pressure systems are more expensive due to the need to use reinforced piping and additional water tanks in the waterworks.

High pressure systems are provided at industrial enterprises that are more than 2 km away from fire departments, as well as in settlements with a population of up to 500 thousand people.

A schematic diagram of a combined water supply system is shown in Fig. 14.2. Water from a natural source enters the water intake and then by the pumps of the first lift station is supplied to the structure for treatment, then through the water lines to the fire control structure (water tower) and then along the main water lines to the inputs to the buildings. The device of water-pressure structures is associated with the unevenness of household water consumption by the hours of the day. Typically a fire fighting network

the water supply system is made circular, which ensures high reliability of water supply.

The rated water consumption for fire extinguishing consists of the costs of external and internal fire extinguishing. When rationing the water consumption for outdoor fire extinguishing, one proceeds from the possible number of simultaneous fires in a settlement that occur within three adjacent hours, depending on the number of inhabitants and the number of storeys of buildings. Consumption rates and water pressure in internal water pipelines in public, residential and auxiliary buildings are regulated by SNiP 2.04.01-85 * depending on their number of storeys, corridor length, volume, purpose.

For fire extinguishing in premises, automatic fire extinguishing devices are used. The most widespread are installations that use sprinkler or deluge heads as distribution devices.

The sprinkler head (fig. 14.3) is a device that automatically opens the water outlet when the temperature inside the room rises, caused by a fire. The sensor is the sprinkler head itself, equipped with a fusible lock, which melts when the temperature rises and opens a hole in the water pipe above the fire. The sprinkler installation consists of a network of water supply and irrigation pipes installed under the ceiling. Sprinklers are screwed into the irrigation pipes at a certain distance from each other.

heads. One sprinkler is installed on an area of 6-9 m2, depending on the fire hazard of the production. If the air temperature in the protected room can drop below +4 ° C, then such objects are protected by air sprinkler systems, which differ from water systems in that these systems are filled with water only up to the control and signaling device, distribution pipelines located above this device in an unheated room, filled with air supplied by a special compressor.

Deluge installations (Fig. 14.4) are similar in design to sprinkler installations, but differ from the latter in that the sprinklers on the distribution pipelines do not have a fusible lock and the holes are constantly open. Deluge systems are designed to form water curtains, to protect a building from fire in a fire in a neighboring building, to form water curtains in a room for the purpose of

prevention of the spread of fire and for fire protection in conditions of increased fire hazard. The deluge system is turned on manually or automatically by a signal from an automatic fire detector using a control and launch unit located on the main pipeline.

Air-mechanical foams can also be used in sprinkler and deluge systems.

Primary fire extinguishing means include fire extinguishers, sand, earth, slags, blankets, shields, sheet materials.

Fire extinguishers are designed to extinguish ignitions and fires at the initial stage of their occurrence. Depending on the conditions for extinguishing fires, various types of fire extinguishers have been created, which are divided into two main groups: portable and mobile.

By the type of extinguishing agent, fire extinguishers are classified:

A) for foam (OP): - chemical foam (OHP);

Air-foam (ORP);

B) gas:

Carbon dioxide (OU) - serves carbon dioxide in the form of gas or snow (liquid carbon dioxide is used as a charge);

Halon (OH) aerosol and carbon dioxide-bromoethyl - serve vapor-generating fire extinguishing agents;

B) powder (OP) - fire extinguishing powders are fed;

D) water (ОВ) - are divided according to the type of the outgoing jet (finely atomized, atomized and compact).

Moderately flammable (B2), having a critical surface heat flux density of at least 20, but not more than 35 kilowatts per square meter;

Hardly flammable (B1), having a critical surface heat flux density of more than 35 kilowatts per square meter;

Highly flammable (G4), having a flue gas temperature of more than 450 degrees Celsius, the degree of damage along the length of the test sample is more than 85 percent, the degree of damage by the mass of the test sample is more than 50 percent, the duration of self-combustion is more than 300 seconds.

Normally combustible (G3), having a flue gas temperature of not more than 450 degrees Celsius, the degree of damage along the length of the test sample is more than 85 percent, the degree of damage by the mass of the test sample is not more than 50 percent, the duration of self-combustion is not more than 300 seconds;

Moderately flammable (G2), having a flue gas temperature of not more than 235 degrees Celsius, the degree of damage along the length of the test sample is not more than 85 percent, the degree of damage by the mass of the test sample is not more than 50 percent, the duration of self-burning is not more than 30 seconds;

Low-flammable (G1), having a flue gas temperature of not more than 135 degrees Celsius, the degree of damage along the length of the test sample is not more than 65 percent, the degree of damage by the mass of the test sample is not more than 20 percent, the duration of self-combustion is 0 seconds;

Combustible - substances and materials that can ignite spontaneously, as well as ignite under the influence of an ignition source and burn independently after its removal.

Hard-combustible - substances and materials that can burn in the air when exposed to an ignition source, but are unable to burn independently after its removal;

The standard establishes a test method for flame propagation over materials of surface layers of floor and roof structures, as well as their classification according to flame propagation groups. The standard applies to all homogeneous and layered combustible building materials used in the surface layers of floor and roof structures.

Designation:	GOST 30444-97
Russian name:	Building materials. Flame Propagation Test Method
Status:	acts
Date of text update:	05.05.2017
Date added to the database:	12.02.2016
Effective date:	20.03.1998
Approved by:	03/20/1998 Gosstroy of Russia (Russian Federation Gosstroy 18-21) 04/23/1997 Interstate Scientific and Technical Commission for Standardization and Technical Regulation in Construction (MNTKS)
Published:	GUP CPP (CPP GUP 1998)
Download links:

GOST R51032-97

STATE STANDARD OF THE RUSSIAN FEDERATION

CONSTRUCTION MATERIALS

TEST METHOD
TO SPREAD THE FLAME

MINSTROY OF RUSSIA

Moscow

Foreword

1 DEVELOPED by the State Central Research and Design Institute for Complex Problems of Building Structures and Structures named after V. A. Kucherenko (TsNIISK named after Kucherenko) of the State Scientific Center "Construction" (State Scientific Center "Construction"), the All-Russian Research Institute of Fire Defense (VNIIPO) of the Ministry of Internal Affairs of Russia with the participation of the Moscow Institute of Fire Safety of the Ministry of Internal Affairs of Russia

INTRODUCED by the Department of Standardization, Technical Regulation and Certification of the Ministry of Construction of Russia

2 ADOPTED and put into effect by the Resolution of the Ministry of Construction of Russia dated December 27, 1996 No. 18-93

Introduction

This standard was developed on the basis of the draft standard ISO / PMS 9239.2 "Basic tests - Reaction to fire - Propagation of flame along the horizontal surface of floor coverings under the action of a radiation heat source of ignition".

Dimensions are given for reference in mm

1 - test chamber; 2 - platform; 3 - sample holder; 4 - sample; 5 - chimney;
6 - exhaust umbrella; 7 - thermocouple; 8 - radiation panel; 9 - gas-burner;
10 - door with inspection window

Picture 1 - Flame Propagation Testing Machine

The installation consists of the following main parts:

1) a test chamber with a flue and an exhaust hood;

2) a source of radiant heat flux (radiation panel);

3) ignition source (gas burner);

4) a sample holder and a device for introducing the holder into the test chamber (platform).

The installation is equipped with devices for recording and measuring the temperature in the test chamber and the chimney, the surface density of the heat flux, the air flow rate in the chimney.

7.2 The test chamber and chimney () are made of sheet steel with a thickness of 1.5 to 2 mm and lined from the inside with a non-combustible thermal insulation material with a thickness of at least 10 mm.

The front wall of the chamber is equipped with a door with a viewing window made of heat-resistant glass. The size of the viewing window should be such that the entire surface of the sample can be observed.

7.3 The chimney is connected by a scammer through the opening. An exhaust ventilation umbrella is installed above the chimney.

The capacity of the exhaust fan must be at least 0.5 m 3 / s.

7.4 The radiation panel has the following dimensions:

The electrical power of the radiation panel must be at least 8 kW.

The angle of inclination of the radiation panel () to the horizontal plane must be (30 ± 5) °.

7.5 The ignition source is a gas burner with an outlet diameter of (1.0 ± 0.1) mm, which ensures the formation of a flame with a length of 40 to 50 mm. The design of the burner must ensure the possibility of its rotation about the horizontal axis. During the test, the flame of the gas burner must touch the point "zero" ("0") of the longitudinal axis of the sample ().

Dimensions are given for reference in mm

1 - holder; 2 - sample; 3 - radiation panel; 4 - gas-burner

Picture 2 - The diagram of the mutual arrangement of the radiation panel,
sample and gas burner

7.6 The platform for placing the sample holder is made of heat-resistant or stainless steel. The platform is installed on the guides at the bottom of the chamber along its longitudinal axis. The entire perimeter of the chamber between its walls and the edges of the platform should be provided with a gap with a total area of (0.24 ± 0.04) m 2.

The distance from the exposed surface of the sample to the ceiling of the chamber should be (710 ± 10) mm.

7.7 The specimen holder is made of heat-resistant steel with a thickness of (2.0 ± 0.5) mm and is equipped with devices for holding the specimen ().

1 - holder; 2 - fasteners

Figure 3 - Sample holder

7.8 To measure the temperature in the chamber (), use a thermoelectric converter in accordance with GOST 3044 with a measurement range from 0 to 600 ° C and a thickness of no more than 1 mm. To record the readings of a thermoelectric converter, devices with an accuracy class of no more than 0.5 are used.

7.9 To measure PPTP, water-cooled receivers of thermal radiation with a measurement range of 1 to 15 kW / m 2 are used. The measurement error should be no more than 8%.

To register the readings of a thermal radiation receiver, a recording device with an accuracy class of no more than 0.5 is used.

7.10 To measure and record the air flow velocity in the chimney, anemometers with a measurement range of 1 to 3 m / s and an intrinsic relative error of not more than 10% are used.

8 Calibration of the installation

8.1 General

9.6 Measure the long-damaged part of the specimen along its longitudinal axis for each of the five specimens; the measurements are carried out with an accuracy of 1 mm.

Damage is considered to be burnout and charring of the sample material as a result of the spread of flame combustion over its surface. Melting, warping, sintering, swelling, shrinkage, change in color, shape, violation of the integrity of the sample (ruptures, surface chips, etc.) are not damage.

10 Expression of test results

10.1 The length of the flame propagation is determined as the arithmetic mean over the length of the damaged part of five samples.

10.2 The value of KPTPF is established on the basis of the results of measuring the length of flame propagation (10.1) according to the graph of the distribution of PTPP over the surface of the sample, obtained during the calibration of the installation.

10.3 If there is no ignition of the samples or the length of the flame propagation is less than 100 mm, it should be assumed that the KPPTP of the material is more than 11 kW / m 2.

10.4 In the case of forcible extinguishing of the sample after 30 minutes of testing, the value of the PTPF is determined from the results of measuring the length of flame propagation at the moment of extinguishing and conditionally takes this value equal to the critical value.

10.5 For materials with sanisotropic properties, the smallest of the obtained KPPTP values is used for classification.

11 Test report

The test report contains the following data:

Test laboratory name;

Customer name;

Name of the manufacturer (supplier) of the material;

Description of the material or product, technical documentation, as well as the trade mark, composition, thickness, density, mass and method of making samples, characteristics of the exposed surface, for laminated materials - the thickness of each layer and material characteristics of each layer;

Flame propagation parameters (length of flame propagation, KPPTP), as well as the ignition time of the sample;

Conclusion on the distribution group of the material, indicating the value of the KPPTP;

Additional observations when testing the sample: burnout, charring, melting, swelling, shrinkage, delamination, cracking, and other special observations during flame propagation.

12 Safety requirements

The room in which the tests are carried out must be equipped with supply and exhaust ventilation. The operator's workplace must meet the requirements of electrical safety in accordance with GOST 12.1.019 and sanitary and hygienic requirements in accordance with GOST 12.1.005.

Keywords: building materials , flame spread , surface heat flux , critical heat flux , flame propagation length , test specimens , test chamber , radiation panel

GOST R 51032-97

Group F 39

STATE STANDARD OF THE RUSSIAN FEDERATION

Building materials

Flame Propagation Test Method

Building materials

Spread flame test method

Date of introduction 1997-01-01

1. DEVELOPED by the State Central Research and Design and Experimental Institute for Complex Problems of Building Structures and Structures named after V.A.Kucherenko (TsNIISK named after Kucherenko) of the State Scientific Center "Construction" (State Scientific Center "Construction") Defense (VNIIPO) of the Ministry of Internal Affairs of Russia with the participation of the Moscow Institute of Fire Safety of the Ministry of Internal Affairs of Russia

INTRODUCED by the Department of Standardization, Technical Regulation and Certification of the Ministry of Construction of Russia

2. ACCEPTED and put into effect by the decree of the Ministry of Construction of Russia dated December 27, 1996, No. 18-93

3. GOST 30444-97 "Building materials. Test method for flame propagation", put into effect by the decree of the Gosstroy of Russia dated 03.20.98 N 18-21, is recognized as having the same force with GOST R 51032-97 in the territory of the Russian Federation due to the authenticity of their content.

Introduction

This International Standard is developed on the basis of draft ISO / PMS 9239.2, Basic tests - Reaction to fire - Propagation of flame along a horizontal surface of floor coverings under the influence of a radiation heat source of ignition.

Clauses 6 to 8 of this standard are authentic to the corresponding clauses of draft ISO / PMS 9239.2.

1 area of use

This International Standard specifies a test method for flame propagation on materials of surface layers of floor and roof structures, as well as their classification according to flame propagation groups.

This standard applies to all homogeneous and layered combustible building materials used in the surface layers of floor and roof structures.

Throughout this standard, references are made to the following standards:

GOST 12.1.005-88 SSBT. General sanitary and hygienic requirements for the air of the working area

GOST 12.1.019-79 SSBT. Electrical safety. General requirements and nomenclature of types of protection

GOST 3044-84 Thermoelectric converters. Rated static conversion characteristics

GOST 18124-95 Asbestos-cement flat sheets. Technical conditions

GOST 30244-94 Building materials. Flammability test methods

ST SEV 383-87 Fire safety in construction. Terms and Definitions

In this standard, the terms and definitions of ST SEV 383 are used, as well as the following terms with the corresponding definitions.

Ignition time is the time from the beginning of the exposure of the sample to the flame of the ignition source until its ignition.

Flame spread is the spread of a flame combustion across the surface of a specimen as a result of exposure as specified in this standard.

Flame propagation length (L) - the maximum amount of damage to the surface of the sample as a result of the propagation of flame combustion.

Exposed surface - the surface of the specimen exposed to radiant heat flux and flame from an ignition source when tested for flame propagation.

Surface heat flux density (PPHF) is a radiant heat flux affecting a unit of sample surface.

Critical surface heat flux density (KPPTP) - the amount of heat flux at which flame propagation stops.

4 Key points

The essence of the method consists in determining the critical surface density of the heat flux, the value of which is set according to the length of the flame propagation over the sample as a result of the effect of the heat flux on its surface.

5 Classification of building materials

by groups of flame spread

5.1 Combustible building materials (according to GOST 30244), depending on the size of the KPPTP, are divided into four groups of flame propagation: RP1, RP2, RP3, RP4 (table 1).

Table 1

6 Test pieces

6.1 For testing, make 5 samples of material with dimensions of 1100 x 250 mm. For anisotropic materials, 2 sets of samples are made (for example, weft and warp).

6.2 Samples for the standard test are prepared in combination with a non-combustible base. The method of fastening the material to the base must correspond to that used in real conditions.

As a non-combustible base, asbestos-cement sheets in accordance with GOST 18124 with a thickness of 10 or 12 mm should be used.

The thickness of a specimen with a non-combustible base should be no more than 60 mm.

In cases where the technical documentation does not provide for the use of material on a non-combustible base, samples are made with a base and fasteners that correspond to the real conditions of use.

6.3 Roofing mastics, as well as mastic floor coatings, should be applied to the base in accordance with the technical documentation, but not less than in four layers, while the material consumption when applied to the base of each layer must correspond to that adopted in the technical documentation.

Samples of floors used with paint coatings should be prepared with these coatings applied in four coats.

6.4 The samples are conditioned at a temperature of (20 ± 5) ° С and a relative humidity of (65 ± 5)% for at least 72 hours.

7 Test equipment

7.1 A schematic of the flame propagation test setup is shown in Figure 1.

The installation consists of the following main parts:

1) a test chamber with a chimney and an exhaust hood;

2) a source of radiant heat flux (radiation panel);

3) ignition source (gas burner);

4) a sample holder and a device for introducing the holder into the test chamber (platform).

The installation is equipped with devices for recording and measuring the temperature in the test chamber and the chimney, the values of the surface density of the heat flow, the air flow rate in the chimney.

7.2 The test chamber and chimney (Figure 1) are made of sheet steel with a thickness of 1.5 to 2 mm and lined from the inside with non-combustible heat-insulating material with a thickness of at least 10 mm.

The front wall of the chamber is equipped with a door with a viewing window made of heat-resistant glass. The dimensions of the viewing window should provide the ability to observe the entire surface of the sample.

7.3 The chimney is connected to the chamber through the opening. An exhaust ventilation umbrella is installed above the chimney.

The capacity of the exhaust fan must be at least 0.5 cubic meters / s.

7.4 The radiation panel has the following dimensions:

length ........................................ (450 ± 10) mm;

width ....................................... (300 ± 10) mm.

The electrical power of the radiation panel must be at least 8 kW.

The angle of inclination of the radiation panel (Figure 2) to the horizontal plane should be (30 ± 5) °.

7.5 The ignition source is a gas burner with an outlet diameter of (1.0 ± 0.1) mm, which ensures the formation of a flame with a length of 40 to 50 mm. The design of the burner must ensure that it can be rotated about the horizontal axis. During the test, the flame of the gas burner should touch the point "zero" ("0") of the longitudinal axis of the sample (Figure 2).

Dimensions are given for reference in mm

1 - test chamber; 2 - platform; 3 - sample holder; 4 - sample; 5 - chimney; 6 - exhaust hood; 7 - thermocouple; 8 - radiation panel; 9 - gas burner; 10 - a door with a viewing window

1-holder; 2 -sample; 3 - radiation panel; 4-gas burner

7.6 The platform for placing the sample holder is made of heat-resistant or stainless steel. The platform is installed on guides at the bottom of the chamber along its longitudinal axis. Around the entire perimeter of the chamber between its walls and the edges of the platform, a gap with a total area of (0.24 ± 0.04) m2 should be provided.

The distance from the exposed surface of the sample to the ceiling of the chamber should be (710 ± 10) mm.

7.7 The specimen holder is made of heat-resistant steel with a thickness of (2.0 ± 0.5) mm and is equipped with devices for holding the specimen (Figure 3).

1- holder; 2 - fasteners

Figure 3 - Sample holder

7.8 To measure the temperature in the chamber (Figure 1), use a thermoelectric converter in accordance with GOST 3044 with a measurement range from 0 to 600 ° C and a thickness of not more than 1 mm. To record the readings of a thermoelectric converter, devices with an accuracy class of no more than 0.5 are used.

7.9 To measure PPTP use water-cooled receivers of thermal radiation with a measurement range from 1 to 15 kW / sq. M. The measurement error should be no more than 8%.

To register the readings of the thermal radiation receiver, a recording device with an accuracy class of no more than 0.5 is used.

7.10 To measure and record the air flow velocity in the chimney, anemometers with a measurement range of 1 to 3 m / s and an intrinsic relative error of no more than 10% are used.

8 Calibration of the installation

8.1 General

8.1.1 The purpose of the calibration is to establish the PPTP values required by this standard at the control points of the calibration sample (Figure 4 and Table 2) and to distribute the PPTP over the sample surface at an air flow rate in the chimney (1.22 ± 0.12) m / s.

table 2

8.1.2 Calibration is carried out on a sample made of asbestos-cement sheets in accordance with GOST 18124, with a thickness of 10 to 12 mm (Figure 4).

8.1.3 Calibration is carried out during metrological certification of the installation or replacement of the heating element of the radiation panel.

1 - calibration sample; 2 -holes for heat flow meter

8.2.1 Set the air flow rate in the chimney from 1.1 to 1.34 m / s. To do this, do the following:

An anemometer is placed in the chimney so that its inlet is located along the axis of the chimney at a distance of (70 ± 10) mm from the upper edge of the chimney. The anemometer should be rigidly fixed in the installed position;

Fix the calibration sample in the sample holder and place it on the platform, insert the platform into the chamber and close the door;

Measure the air flow rate and, if necessary, by adjusting the air flow rate in the ventilation system, set the required air flow rate in the chimney in accordance with 8.1.1, after which the anemometer is removed from the chimney.

In this case, the radiation panel and the gas burner are not turned on.

8.2.2 After carrying out work according to 8.2.1, the values of PPTP are established in accordance with Table 2. For this purpose, the following is performed:

The radiation panel is turned on and the chamber is heated until the thermal balance is achieved. The heat balance is considered achieved if the temperature in the chamber (Figure 1) changes by no more than 7 ° C within 10 minutes;

Install a thermal radiation receiver in the hole of the calibration sample at the L2 control point (Figure 4) so that the surface of the sensing element coincides with the upper plane of the calibration sample. The readings of the receiver of thermal radiation are recorded after (30 ± 10) s;

If the measured value of PPTP does not correspond to the requirements specified in Table 2, the power of the radiation panel is adjusted to achieve the heat balance and the measurements of PPTP are repeated;

The above operations are repeated until the AFT value required by this standard for the L2 reference point is reached.

8.2.3 The operations of 8.2.2 are repeated for the control points L1 and L3 (Figure 4). If the measurement results meet the requirements of Table 2, PPTP measurements are carried out at points located at a distance of 100, 300, 500, 700, 800 and 900 mm from point "0".

Based on the results of the calibration, a graph of the distribution of the PPTP values along the length of the sample is plotted.

9 Testing

9.1 Preparation of the installation for testing is carried out in accordance with 8.2.1 and 8.2.2. After that, the chamber door is opened, the gas burner is ignited and positioned so that the distance between the flame torch and the exposed surface is at least 50 mm.

9.2 Place the sample in the holder, fix its position using the fixing devices, place the holder with the sample on the platform and insert it into the chamber.

9.3 Close the chamber door and start the stopwatch. After holding for 2 min, the burner flame is brought into contact with the sample at point "0" located along the central axis of the sample. Leave the flame in this position for (10 ± 0.2) min. After this time, return the burner to its original position.

9.4 If there is no ignition of the sample within 10 min, the test is considered complete.

In the event of ignition of the sample, the test is terminated when the flame combustion stops or after 30 minutes have elapsed from the start of exposure of the sample to a gas burner by forced extinguishing.

During the test, the ignition time and the duration of the flame combustion are recorded.

9.5 After the end of the test, open the chamber door, extend the platform, and remove the sample.

The test of each successive sample is carried out after cooling the sample holder to room temperature and checking the compliance of the PPTP at point L2 with the requirements specified in Table 2.

9.6 Measure the length of the damaged part of the specimen along its longitudinal axis for each of the five specimens. Measurements are carried out with an accuracy of 1 mm.

Damage is considered to be the burnout and carbonization of the sample material as a result of the spread of flame combustion over its surface. Melting, warping, sintering, swelling, shrinkage, change in color, shape, violation of the integrity of the sample (rupture, surface chips, etc.) are not damage.

10.1 The length of flame propagation is determined as the arithmetic mean over the length of the damaged portion of five specimens.

10.2 The value of KPPTP is established on the basis of the results of measuring the length of flame propagation (10.1) according to the graph of the distribution of PTPF over the surface of the sample obtained during the calibration of the installation.

10.3 In the absence of ignition of the samples or the length of the flame propagation is less than 100 mm, it should be considered that the KPPTP of the material is more than 11 kW / m2.

10.4 In the case of forced extinguishing of the sample after 30 minutes of testing, the value of the PPTP is determined by the results of measuring the length of flame propagation at the moment of extinguishing and conditionally take this value equal to the critical value.

10.5 For materials with anisotropic properties, the smallest of the obtained KPPTP values is used for classification.

11 Test report

The test report contains the following data:

Test laboratory name;

Customer name;

Name of the manufacturer (supplier) of the material;

Flame propagation parameters (flame propagation length, KPPTP), as well as the ignition time of the sample;

Conclusion on the distribution group of the material, indicating the value of the KPPTP;

Additional observations when testing the sample: burnout, charring, melting, swelling, shrinkage, delamination, cracking, and other special observations during flame propagation.

12 Safety requirements

Introduction

1 area of use

3 Definitions, symbols and abbreviations

4 Key points

5 Classification of building materials according to flame propagation groups

6 Test pieces

7 Test equipment

Figure 1 - Flame propagation test apparatus

Figure 2 - Diagram of the mutual arrangement of the radiation panel, sample and gas burner

Figure 3 - Sample holder

8 Calibration of the installation

8.1 General

Figure 4 - Calibration sample

8.2 Calibration procedure

9 Testing

10 Expression of test results

11 Test report

12 Safety requirements

UDC 691.001.4: 006.354 OKS 91.100 OKSTU 5719

Key words: building materials, flame propagation, surface heat flux density, critical heat flux density, flame propagation length, test specimens, test chamber, radiation panel.

The method is large-scale, which is associated with the dimensions of the installation (shaft furnace) and samples of the test material.

It is used for testing all homogeneous and layered combustible materials, including those used as finishing and facing, as well as paint and varnish coatings.

The essence of the method lies in exposing a sample of the material to the flame of a gas burner for 10 minutes and recording the parameters characterizing its behavior under fire exposure.

12 samples. Sample sizes: 1000x190 mm, thickness up to 70 mm. they are placed vertically, folded in 4 in the form of a box.

The test setup is a vertical shaft furnace.

The sequence of operations in the test process is as follows.

Weigh the samples and attach them to the holder frame. 4.

Insert samples 6 into the combustion chamber 9, fix and close the door 5.

Turn on the fan 13 (turning on the fan is the beginning of the test).

Light the gas burner 10.

From the moment of the start of the tests, the temperature of the flue gases is recorded within 10 minutes using thermocouples 8 and the self-burning time of the sample.

After testing, the cooled samples are removed from the oven, the length of the damaged part of the samples is measured and weighed.

The test results are evaluated according to the table. 1.5.

Table 1.5

Classification of materials by flammability groups

Group flammability materials	Flammability parameters
Group flammability materials	Flue gas temperature /, ° С	Length of damageSi, %	Damage by weightSu, %	Duration of independent COMBUSTION 1sg,with

Note. For materials of flammability groups G1-GZ, the formation of burning melt drops during testing is not allowed.

Flammability Test Method for Materials

. The method is used for all homogeneous and layered combustible building materials.

The essence of the method consists in determining the flammability parameters of the material at given standard levels of exposure to the sample surface of a radiant heat flux and flame from an ignition source, which are determined on the device shown in Fig. 1.8.

Flammability parameters are KPPTP - critical surface heat flux density and ignition time.

КППТП - the minimum value of the surface heat flux density (ППТП), at which a stable

flaming combustion. KPPTP is used to classify materials according to flammability groups.

Levels of exposure to radiant heat flux should be in the range from 5 to 50 kW / m 2.

For testing, 15 samples are prepared, having the shape of a square with a side of 165 (-5) mm, a thickness of not more than 70 mm.

The test order is as follows.

After conditioning, the sample is wrapped in a sheet of aluminum foil, in the center of which a hole with a diameter of 140 mm is cut.

Turn off the power supply and set the thermo-EMF (voltage) value obtained during the calibration of the installation using the regulating thermoelectric converter (thermocouple), corresponding to PPTP 30 kW / m 2.

After reaching the specified value of thermo-EMF, the installation is kept in this mode for at least 5 minutes. In this case, the value of thermo-EMF should not deviate by more than 1%.

Place the shielding plate on the shielding plate, replace the simulator with a test specimen, turn on the movable torch mechanism, remove the shielding plate, and turn on the time recorder.

Stop the test after 15 minutes or if the sample is ignited. To do this, place the shielding plate on the protective plate, stop the time recorder and the movable burner mechanism, remove the holder with the sample and place the simulator sample on the movable platform, remove the shielding plate.

The value of PPTP is set to 20 kW / m 2 (if ignition was recorded in the previous test) or 40 kW / m 2 in its absence. Repeat the operations on p. 5-7.

If at PPTP 20 kW / m 2 ignition is recorded, reduce the value of PPTP to 10 kW / m 2 and repeat operations 5-7.

If there is no ignition at PPTP 40 kW / m 2, set the value of PPTP 50 kW / m 2 and repeat operations 5-7. In the absence of ignition at PPTP 50 kW / m 2, 2 more tests are carried out with this PPTP, and if ignition is not observed, then the tests are stopped.

11. After determining two values of PPTP, one of which is observed ignition, and the other is absent, set the value of PPTP by 5 kW / m 2 more than the value at which there is no ignition, and repeat the operations of paragraphs 5-7 on three samples.

For KPPTP consider the smallest value of PITP, at which for the sin of samples the ignition is fixed.

The flammability of materials is assessed by

Flame Propagation Test Method for Materials

The method is used to test all homogeneous and layered combustible materials used in the surface layers of floors and roofs of buildings.

The essence of the method is to determine the critical surface heat flux density (KPPTP), the value of which is set along the length of the flame propagation along the sample as a result of the effect of the heat flux on its surface.

Flame propagation length (I) - the maximum amount of damage to the surface of the sample as a result of the propagation of flame combustion.

For testing, 5 samples of material with a size of 1100 x 250 mm are made. For anisotropic materials, 2 sets of samples are made (for example, weft and warp). Samples are prepared in combination with a non-combustible base. The method of fastening the material to the base must correspond to that used in real conditions. Asbestos-cement sheets with a thickness of 10 or 12 mm are used as a non-combustible base. The thickness of a specimen with a non-combustible base should be no more than 60 mm.

The test setup consists of the following main

test chamber with chimney and exhaust hood;

a source of radiant heat flux (radiation panel);

an ignition source (gas burner);

a sample holder and a device for introducing the holder into the test chamber (platforms).

The installation is equipped with devices for recording and measuring the temperature in the test chamber and chimney.

The test order is as follows.

After calibrating the installation, i.e. after establishing the required GOST values of the PPTP at the specified points of the calibration sample and on its surface, as well as preparing it for operation, open the chamber door and ignite the gas burner, positioning it so that the distance to the exposed surface is at least 50 mm.

Place the sample in the holder, fix it, place them on the platform and introduce them into the chamber.

Close the cell door and start the stopwatch. After holding for 2 min, the burner flame is brought into contact with the sample at the point

located on the central axis. Leave the flame in this position for 10 minutes. After the expiration of the time, the burner is returned to its original position.

If the sample has not ignited within 10 minutes, the test is considered complete. In the event of ignition of the sample, the test is terminated when the flame combustion has ceased or after 30 minutes.

the sample is carried out after cooling the sample holder to room temperature and checking the compliance of the PPTP with the requirements of GOST.

Measure the length of the damaged part of the sample along its longitudinal axis for each of the five samples.

The length of the flame propagation is determined as the arithmetic mean over the length of the damaged part of five samples.

Combustible building materials, depending on the size of the KPPTP, are divided into 4 groups of flame propagation

Critical surface heat flux density GOST. Building materials

Introduction

8 Calibration of the installation

10 Expression of test results

11 Test report

12 Safety requirements

Classification of materials by flammability groups

Flammability Test Method for Materials