What building materials refer to non-combustible. What is a combustible group G1
"Fire safety of buildings and structures" on the fire and technical classification of building materials, as well as the provisions of other regulatory framework for fire safety, to which this document refers.
For non-combustible building materials, other indicators of fire danger are not defined and are not normalized.
flammability - The ability of substances and materials to ignition.
ignition is the beginning of fiery burning under the action of the ignition source, with a real standard test is characterized by steady flame burning.
ignition time - Time from the beginning of the test before the emergence of sustainable flame burning.
sustainable flame burning - The burning that continues to the next effect on the sample of the flame from the ignition source.
Radiant thermal stream, affecting the unit of the sample surface.
The minimum value of the surface density of the heat flux at which a stable flame burning occurs.
flame spread - the spread of fiery burning on the surface of the sample as a result of the impact provided for in this standard;
surface Density of Heat Flow (PTTP) - radiant thermal flow, affecting the unit of the sample surface;
critical surface density of thermal flux (PPPTP) - The magnitude of the heat flux in which the spread of the flame is stopped.
In paragraph 5.7, SNIP 21-01-97 * found that combustible building materials for smoke-forming ability are divided into three groups:
D1 (with low smoke-forming ability);
D2 (with moderate smoke-forming ability);
D3 (with high smoke-forming ability).
Group of building materials for smoke-forming ability are established according to GOST 12.1.044-89 "CBST. Firelessness of substances and materials. Nomenclature of indicators and methods of their definition." The specified document contains the following provisions regarding the smoke coefficient.
Smoke formation coefficient - An indicator that characterizes the optical density of smoke formed during flame burning or thermo-oxidative destruction of a certain amount of solid (material) under special tests.
The value of the smoke coefficient should be used to classify materials for smoke-forming ability. Three groups of materials distinguish:
with low smoke-forming ability - smoke-forming coefficient up to 50 m2kg-1 included.;
with moderate smoke-forming ability - the smoke-forming coefficient of St. 50 to 500 m2kg-1 included;
with high smoke-forming ability - the smoke formation coefficient of SV. 500 m2kg-1.
The smoke coefficient value must be included in the standards or technical conditions on solids and materials.
In accordance with paragraph 5.8 SNiP 21-01-97 * combustible construction materials for the toxicity of combustion products are divided into four groups:
T1 (low hazard);
T2 (moderate);
T3 (highly hazardous);
T4 (extremely dangerous).
Group of building materials for the toxicity of combustion products are set according to GOST 12.1.044-89 "CBST. Firelessness of substances and materials. Nomenclature of indicators and methods of their definition." The named document in relation to the toxicity of the products of combustion of polymeric materials provides for the following.
The level of toxicity of combustion products is the ratio of the amount of material to a unit of volume of closed space, in which the produced gaseous products formed during combustion causes the death of 50% of experimental animals.
The value of the combustion product toxicity indicator should be used for a comparative estimate of polymeric materials, as well as include in the technical conditions and standards for finishing and thermal insulation materials. The classification of materials by the value of the combustion product toxicity indicator is given in the table.
The essence of the method for determining the toxicity indicator lies in the combustion of the material under study in the combustion chamber at a given density of the heat flux and detecting the dependence of the lethal effect of gaseous combustion products from the mass of the material related to the unit volume of the exposure chamber.
The table that is installed in GOST 12.1.044-89 is played in Table 2 of the application to the commented law (see Comment on the specified table).
11. In accordance with Part 11 of the commented article, the classes of fire danger of building materials are allocated depending on the fire hazard groups of building materials. These classes are km 0, km1, km2, km3, km4 and km5 are shown in Table 3 of the Annexes to the commented law. It should be noted that the allocation of these classes is an innovation, since earlier in regulatory documents on fire safety (first of all, in SNIP 21-01-97 * "Fire safety of buildings and structures") only groups of fire hazard of building materials were allocated.
12. In part 12
Classification of building materials
By origin and appointment
By origin, building materials can be divided into two groups: natural and artificial.
Natural Call such materials that are found in nature in the finished form and can be used in construction without substantial processing.
Artificial Call building materials that are not found in nature, but are manufactured using various technological processes.
For appointment, building materials are divided into the following groups:
Materials intended for the construction of walls (brick, wood, metals, concrete, reinforced concrete);
Binding materials (cement, lime, gypsum) used to obtain non-burning products, masonry and plaster;
Thermal insulation materials (foam and aerated concrete, felt, mineral wool, foam, etc.);
Finishing and facing materials (stone rocks, ceramic tiles, various types of plastics, linoleum, etc.);
Roofing and waterproofing materials (roofing steel, tile, asbestos-cement sheets, slate, tol, rubberoid, isol, brizol, porerizol, etc.)
Non-combustible building materials
Natural stone materials. Natural stone materials are called building materials obtained from rocks due to the use of only mechanical processing (crushing, sawing, splitting, grinding, etc.). They are used to build walls, furniture of floors, stairs and foundations of buildings, cladding of various designs. In addition, rock rocks are used in the production of artificial stone materials (glasses, ceramics, thermal insulation materials), as well as raw materials for the production of binding substances: gypsum, lime, cement.
The action of high temperatures on natural stone materials. All natural stone materials used in construction are non-combustible, however, under the influence of high temperatures in stone materials, various processes occur, leading to reduction of strength and destruction.
Minerals included in the stone materials have different coefficients of temperature expansion, which can lead to the occurrence of internal stresses in the stone and the appearance of the defects of its internal structure.
The material undergoes a modification conversion of the structure of the crystal lattice associated with a jump-shaped increase in volume. This process leads to the cracking of monolith and the fall in the strength of the stone due to large temperature deformations resulting from sharp cooling.
It should be emphasized that all stone materials under the influence of high temperatures lose their properties irreversibly.
Ceramic products. Since all ceramic materials and products in the process of obtaining them are subjected to burning at high temperatures, the reinforcement of high temperatures under fire conditions does not have a significant effect on their physicomechanical properties, if these temperatures do not reach softening temperatures (melting) of materials. Porous ceramic materials (clay ordinary brick, etc.), obtained by a firing, not prone to sintering, may be exposed to moderately high temperatures, as a result of which some shrinkage of the structures made of them are possible. The effects of high temperatures in a fire on dense ceramic products, the root of which is carried out at temperatures of about 1300 ° C, practically does not have any harmful effect, since the temperature on the fire does not exceed the firing temperature.
Red clay brick is the best material for the device of fire walls.
Metals. In construction, metals are widely used for the construction of industrial and civil buildings in the form of steel rolling profiles. A large amount of steel is on the manufacture of reinforcement reinforced concrete. Apply steel and cast iron pipes, roofing steel. In recent years, lightweight building structures from aluminum alloys are becoming increasingly wider.
Behavior steels in the fire. One of the most characteristic features of all metals is the ability to soften when heating and restore its physico-mechanical properties after cooling. In case of fire, metal structures are very quickly warmed, lose strength, deform and convert.
Worse in the conditions of the fire, reinforcement steel will behave (see the "Reference Materials" section), which are obtained by additional hardening by the methods of heat treatment or cold broach (stagnation). The reason for this phenomenon is that the additional strength of these steel is obtained by distorting the crystal lattice, and under the influence of heating, the crystal lattice is returned to an equilibrium state and the strength gain is lost.
Aluminum alloys. The disadvantage of aluminum alloys is the high coefficient of temperature expansion (2-3 times more than steel). When heated, a sharp decrease in their physicomechanical indicators occurs. The strength limit and the yield strength of aluminum alloys used in construction are reduced by about twice at 235-325 ° C. In a fire conditions, the temperature in the volume of the room can achieve these values \u200b\u200bin less than one minute.
Materials and products based on mineral melts and glass melts products. This group includes: glass materials, slag and stone casting, sitals and slagositallas, leaf window and showcase glass, patterned, reinforced, sun- and heat shield, facing glass, fiberglass, double glazing, glass carpet-mosaic tiles, glass blocks, etc. .
The behavior of materials and products from mineral melts in high temperatures. Materials and products made of mineral melts are non-combustible and cannot contribute to the development of fire. The exceptions are materials made on the basis of mineral fibers with a content of a certain amount of organic binder, such as heat-insulating mineral plates, silica plates, plates and rolled mats from basalt fiber. The combustibility of such materials depends on the number of entered binder. In this case, the fire hazard will be determined mainly by the properties and number of polymer in the composition.
Window glass does not withstand long heat loads in a fire, but at slow heating may not be collapped for quite a long time. The destruction of glass in light openings begins almost immediately after the flame begins to touch its surface.
Constructions from tiles, stones, blocks obtained based on mineral melts have significantly greater fire resistance than sheet glass, as, even cracking, they continue to carry a load and remain impermeable for combustion products. Porous materials from mineral melts retain their structure almost to the melting point (for foam glass, for example, this temperature is about 850 ° C) and heat-protective functions are performed for a long time. Since porous materials have a very slight thermal conductivity coefficient, even at the moment when the side facing the fire will be melted, heat-shielding functions can perform deeper layers.
Combustible building materials
Wood. When the wood is heated to 110 ° C, moisture is removed from it, and gaseous products of thermal destruction (decomposition) begin to be released. When heated to 150 ° C, the heated surface of the wood turns yellow, the amount of volatile substances stands up. At 150-250 ° C, the wood acquires a brown color due to charring, and at 250-300 ° C, the wood decomposition products are ignited. The temperature of self-ignition wood is within 350-450 ° C.
Thus, the process of thermal decomposition of wood flows into two phases: the first phase - decay - is observed when heated to 250 ° C (to the ignition temperature) and it comes with the absorption of heat, the second, the combustion process itself, comes with heat release. The second phase, in turn, is divided into two periods: the combustion of the gases formed during thermal decomposition of wood (fiery burning phase), and the combustion of the formed charcoal (phase).
Bituminous and tarmers. Building materials, which include bitumens or tar, are called bitumen or degrees.
Ruberoid and Toler roofs can light up even from low-power sources of fire, such as sparks, and continue to burn themselves, highlighting a large number of thick black smoke. When burning bitumeumes and they soften and spread out, which significantly complicates the situation on the fire.
The most common and effective way to reduce the ignition of the roofs made of bitumen and tariff materials is the sprinkler of their sand, filling in the solid layer of gravel or slag, coating with any non-combustible tiles. Some flame retardant effect gives the coating of rolled materials with foil - such coatings are not flammable under the influence of sparks.
It should be borne in mind that rolled materials made using bitumens and descendants in the rolled state are prone to self-burning. This circumstance must be taken into account when storing such materials.
Polymer building materials. Polymer building materials (PSM) are classified according to various features: the type of polymer (polyvinyl chloride, polyethylene, phenol formaldehyde, etc.), production technology (extrusion, injection molding, roller-calender, etc.), destination in construction (structural, finishing materials for floors , Heat-soundproof materials, pipes, sanitary and hardware, mastic and adhesives). All polymeric building materials have high flammability, smoke-forming ability and toxicity.
New class of linoleum km2 B2, d2, T2, RP1
In July 2012, the long-awaited events occurred, made great changes to the federal law. Now questions such as: Non-combustible linoleum, Linoleum G1, Linoleum G1, B1 are not relevant . The main indicators is Linoleum Classm, It can be km1, km2, km3, km4 and km5. The fire safety class is determined by such indicators as: flammability (B2), smoke-forming ability (D2), toxicity (T2), flame proliferation (RP1). Linoleum Now you need to choose, only on the basis of class Km1, km2, km3, km4, km5 and it is important to remember and know. Next, we give a table with old indicators, where the changes in which the changes contributed to the law.According to a change in federal law (hereinafter referred to as FZ No. 117) vinyl linoleum km2 In hospitals, schools and children's preschool, educational institutions are significantly expanded.
New Fire Danger Requirements for Outdoor Coatings
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Properties of fire fire hazard construction materials |
Km 0. | Km1 | Km2 | Km3 | Km4. | Km5 |
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Spray |
NG | G1. | G1. | Г2. | G3 | G4 |
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Flammability |
IN 1 | AT 2 (was B1) | AT 2 | IN 3 | ||
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Smoke-forming |
D 2 (It was D1) | D2 (was D3 +) | D3. | D3. | ||
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Toxicity |
T2. (was T1) | T2. | T2. | T4. | ||
|
Flame spread |
RP1 | RP1 | RP2 (was RP1) | RP2. | RP4 |
Homogeneous linoleum km2
| Type of coating | Brand | Fire indicators | ||
| iQ Monolit. iQ Aria iqmelodia. iQ Zenith. Plus Primo. Kerama. |
Tarkett. |
B2, d2, T2, RP1 |
Km2 |
|
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Horizon. |
Sinteros. |
B2, d2, T2, RP1 |
Km2 |
In harvesters, including children's preschool, general education institutions, hospitals. On the Evacuation paths up to 17 floors. (Cannot be laid on the stairwells and in the lobbies in the Dow, stairwells and the lobby of hospitals, and on the stairwells and in the lobbies of buildings more than 17 floors) |
Heterogeneous linoleum km2
| Type of coating | Brand | Fire indicators | New fire hazard class |
Permitted scope |
|
Acczent Universal Prizma.City. Modawood. |
Tarkett. |
B2, d2, T2, RP1 |
Km2 |
In harvesters, including children's preschool, general education institutions, hospitals. On the Evacuation paths up to 17 floors. (Cannot be laid on the stairwells and in the lobbies in the Dow, stairwells and the lobby of hospitals, and on the stairwells and in the lobbies of buildings more than 17 floors) |
|
Tarkett. |
B2, D3, T2, RP1 |
Km3 |
In harvesters with a number of up to 300 people, in common corridors, halls and lobby in buildings up to 17 floors. (Cannot be used in wards, bedrooms and children's preschool institutions) |
No longer needed a flammability group on floor coverings of linoleum (M1, G2, G3, G4)
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Purpose |
The list of necessary indicators depending on |
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group |
group |
group |
group |
group |
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Materials for |
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Materials for |
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Roofing |
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Waterproofing |
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Heat insulating |
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Notes: 1. The "+" sign indicates that the indicator must be applied.
2. The sign "-" indicates that the indicator does not apply.
You can also apply PVC coatings, commercial linoleum, in most rooms that are considered evacuation paths.
All you need to know, articles how to choose outdoor coverage
To determine the probability of the appearance of a flame, the main importance of the substances and various materials has a combustibility. This characteristic determines the category of fire danger of structures, premises, industries; Allows you to correctly select the tools to eliminate foci.
The combustion group of all material components of the object determines the success of fire combating, minimizes the likelihood of victims.
Features of various substances
It is known that substances can be in various aggregate states that are important to take into account by defining a combustibility group. GOST provides a classification based on quantitative indicators.
If the substance can be lit, a combustibility group G1 is most optimal to fire safety than g3 or g4.
The combustibility is of great importance for finishing, thermal insulation, building materials. On its basis, the class of fire danger is determined. Thus, plasterboard sheets have a combustibility group of G1, stone wool - NG (not lit), and insulation expanded polystyrene foam in the combustion system of G4, and reduce its fire hazard helps the use of plaster.
Gaseous substances
Determining the gramificence class of gases and liquids, the standards introduce such a concept as a concentration limit. By definition, this is the maximum concentration of gas in a mixture with an oxidizing agent (by air, for example), in which the flame can spread from the ignition point at any distance.
If there is no such boundary value, and the gas cannot be self-propagated, then it is called non-combustible.
Liquid
Fluids are combined, if there is a temperature at which they can ignite. If the fluid ceases to burn in the absence of an external heating source, then it is called difficulty. Non-combustible fluids do not light up in the air atmosphere under normal conditions.
Some fluids (acetone, ether) can flash at 28 and below. They are part of particularly dangerous. Tanning fluids at 61 ... 66 ℃ and above are referred to as flammable (kerosene, White spirit). Tests are carried out in an open and closed crucible.
Solid
In the field of construction, the most relevant is the definition of a combustibility group of solid materials. It is preferable to use substances of the combustibility group of G1 or NG, as the most resistant to ignition.
Classification
The intensities of the combustion process and the conditions of its flow determines the likelihood of a fire enhancement, an explosion occur. The outcome of the incident depends on the combination of the properties of the feedstock.
General division
According to the national standard of fire and explosive danger, substances and diverse materials of them are divided into the following groups:
- absolutely non-flammable;
- difficult to burn;
- combustible.
Can not burn in air, which does not exclude the interaction with oxidizing agents, with each other, water. Consequently, some representatives of the group under certain conditions represent fire hazard.
It is difficult to combine compounds that are burning during the ignition in air. As soon as the source of the fire is eliminated, the burning stops.
Flawing substances in certain conditions light up or in the presence of a source of fire, continue to burn intensively.
Classification for the combustibility of building raw materials and products is considered in a separate updated standard. Construction nationwide norms take into account the categories of all types of products used in the work.
According to this classification, non-combustible building materials (NG) are divided into two groups depending on the test mode and values \u200b\u200bof the indicators obtained.
In the group 1 includes products, with a study of which the temperature inside the furnace increases no more than 50 ℃. Reducing the mass of the sample does not exceed 50%. The flame is not lit at all, and the released heat does not exceed 2.0 MJ / kg.
In 2, the NG group includes materials with the same indicators of temperature increase inside the furnace and mass loss. The difference is that the flame burns up to 20 seconds, the heat of the combustion should not be greater than 3.0 mJ / kg.
Classes of aghounds
The combustible materials are investigated by similar criteria, divided into 4 groups or classes, which denote the letter G and the number located next to it. For classification, the values \u200b\u200bof the following indicators take into account:
- gas temperatures released with smoke;
- degree of size reduction;
- weight reduction value;
- flame saving time without a combustion source.
K G1 includes a group of materials with a smoke temperature not exceeding 135. Loss of length is stacked by 65%, weight - 20%. Flame itself does not burn. Such construction products are called self-fighting.
In G2 includes a group of materials with a smoke temperature not exceeding 235. Loss of length is laid in 85%, the masses - 50%. Independent burning continues not more than 30 seconds.
K g3 includes materials in which the smoke temperature does not exceed 450. Loss of length is more than 85%, weight - up to half. Flame itself burns no more than 300 seconds.
The combustible group G4 includes materials in which the smoke temperature exceeds 450 ° C. Loss of length exceeds 85%, masses - more than 50%. Independent combustion lasts more than 300 seconds.
It is permissible to use the following consoles in the title of each combustion group in the order of increasing the digital index:
- weakly;
- moderately;
- fine;
- sylinding materials.
The above combustion indicators along with some other characteristics are necessarily taken into account when developing project documentation, drawing up.
Of great importance also has the ability to form smoke, toxicity of combustion products, the rate of possible spread of fire, the likelihood of rapid ignition.
Class confirmation
Samples of materials are subjected to tests in laboratories and in open areas according to standard methods separately for non-combustible and combustible building materials.
If the products consist of several layers, the regulatory is provided for a flammability check for each layer.
Definitions are carried out on special equipment. If it turns out that one of the combustion components is high, this status will be enshrined in the product as a whole.
Installation for experimental definitions should be indoors with room temperature, normal humidity, without drafts. Bright sunny or artificial light in the laboratory should not interfere with reading testimony from displays.
Before starting the sample study, the device is checked, calibrated, warmed. The sample is then fixed in the furnace's internal cavity holder and immediately include registrars.
The main thing is that no more than 5 seconds have passed since the sample placement. The definition continues to achieve the temperature balance, at which there are no more than 2 ° C for 10 minutes.
At the end of the procedure, the sample along with the holder is removed from the furnace, cooled in the desiccator, weighed and measured, ranging them to the combustibility group NG, G1 and so on.
The method of checking the combustible
All building materials, including finishing, facing, paintwork types of coatings, regardless of homogeneity or multi-layered, are examined by a combustibility in a single method.
Pre-prepare 12 units of identical samples with a thickness equal to real values \u200b\u200bduring operation. If the structure is layered, take samples from each surface.
The samples are then kept at room temperature and normal ambient air humidity at least 72 hours, periodically weighing. Holding should be stopped when a constant mass is reached.
The installation has a standard design, consists of a combustion chamber, air supply systems and removal of released gases.
Samples in turn are placed in the chamber, measurements are carried out, fix the loss of mass, temperature and the number of gas-shaped gaseous products, burning time without a flame source.
Analyzing all the indicators obtained, determine the level of flammability of the material, belonging to a specific group.
Application in construction
During the construction of buildings, several different types of building materials are used: constructive, insulating, roofing, finishing with distinguished assignment and loads. All products should be available and presented to potential buyers certificates.
You should familiarize yourself with the parameters characterizing security, firmly know what can mean each reduction and numbers. The law requires only materials of the combustibility group G1 or NG for construction ceil frames.
The combustible substances and materials are divided into three groups: non-combustible, difficult and combustible.
Non-combustible (challenges) -substances and materials that are not capable of burning in the air. Non-combustible substances can be fireless.
Painty (challenges) -substances and materials capable of burning in the air when exposed to a ignition source, but not able to burn independently after removing it.
Combustible (combustible)- Substances and materials capable of self-turn, as well as ignite when exposed to the source of ignition and on their own, after removing it.
All combustible substances are divided into the following main groups:
Combustible gases (GG) -the substances capable of forming flammable and explosive mixtures with air at temperatures not higher than 50 ° C. The combustible gases include individual substances: ammonia, acetylene, butadiene, butane, butyl acetate, hydrogen, vinyl chloride, isobutane, isobutylene, methane, carbon monoxide, propane, Propylene, hydrogen sulfide, formaldehyde, as well as pairs of flammable and combustible liquids.
Flammable liquids (LVZ) -substances that can burn independently after removing the ignition source and having an outbreak temperature not higher than 61 ° C (in a closed crucible) or 66 ° (in open). Such fluids include individual substances: acetone, benzene, hexane, heptane, dimethylphoramide, diefluorodichloromethane, isopentane, isopropylbenzene, xylene, methyl alcohol, dry carbon, styrene, acetic acid, chlorobenzene, cyclohexane, ethyl acetate, ethylbenzene, ethyl alcohol, and mixtures and mixtures and Technical products Gasoline, diesel fuel, kerosene, Whitespit, solvents.
Combustible fluids (GJ) -substances that can burn independently after removing the ignition source and having an outbreak temperature above 61 ° (in a closed crucible) or 66 ° C (in the open). The following individual substances include combustible fluids: aniline, hexadecan, hexyl alcohol, glycerin, ethylene glycol, as well as mixtures and technical products, such as oils: transformer, vaseline, castor.
Fuel dust(/ 77) - solids that are in fine state. Combustible dust in the air (aerosol) is able to form explosives with him
3 Classification of fire safety rooms
In accordance with the "general-union norms of technological design" (1995), buildings and structures in which production is placed, divided into five categories (Table 5).
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Characteristics of substances and materials located (applying) indoors |
|
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explosion-Ousogenic |
Combustable gases, flammable fluids with an outbreak temperature of no more than 28 ° C in such quantities that can form explosive steam outdoor mixtures, with the ignition of which the calculated excess pressure of the explosion in a room exceeds 5 kPa. Substances and materials capable of exploding and burning when interacting with water, air oxygen or one with another in such a quantity that the calculated excessive pressure of the explosion in the room exceeds 5kpa. |
|
explosion-Roban |
Flashing dust or fibers, flammable fluids with a flash point of more than 28 ° C, combustible fluids in such a quantity that can form explosive dust or pair-air mixtures, with the ignition of which the calculated excessive pressure of the explosion explosion is developing exceeding 5 kPa. |
|
fire hazard |
Combustible and hard-burning liquids, solid combustible and hard-burning substances and materials capable of interacting with water, air oxygen or one with another only to burn, provided that the premises in which they are available or appeal are not related to categories a or b |
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Non-combustible substances and materials in hot, red or molten state, the process of processing which is accompanied by the release of radiant heat, sparks and flames, combustible gases, liquids and solids that are burned or disposed of fuel |
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Non-combustible substances and materials in cold condition |
Category A: Tsekhi processing and applying metal sodium and potassium, oil refineries and chemical production, gasoline and cylinders for combustible gases, stationary acid and alkaline accumulatory plants, hydrogen stations, etc.
