This standard specifies the evaluation and classification standards for the combustion performance of building materials. This standard is applicable to structural materials and various decorative materials used in various industrial and civil construction projects. GB 8624-1997 Classification method for combustion performance of building materials GB8624-1997 standard download decompression password: www.bzxz.net

GB 8624—1997
This standard is a revised version of GB8624--88. In terms of technical content, the first part of German standard DIN4102-81 is adopted in a non-equivalent manner. Compared with GB8624-88, this revised version adds Class A composite (sandwich) materials, and according to the specific conditions of my country, adds specific provisions for floor covering materials for specific purposes, curtain and curtain textiles, wire and cable casing plastic materials, and foam plastics for pipe insulation. If the above-mentioned materials for specific purposes are used as wall or ceiling materials, they must still be inspected and classified according to the provisions of Chapter 4 and Chapter 5 of this standard.
From the date of entry into force of this standard, the original GB8624-88 will be invalid. This standard is proposed by the Ministry of Public Security of the People's Republic of China. This standard is under the jurisdiction of the Seventh Subcommittee of the National Technical Committee for Fire Protection Standardization. This standard is drafted by the Sichuan Fire Science Research Institute of the Ministry of Public Security. The main drafters of this standard are Qian Jianmin, Ma Xianglin, and Lu Guojian. This standard was first issued in February 1988.
National Standard of the People's Republic of China
Classification on burning behaviour for building materials
Classification on burning behaviour for building materials1 Subject content and scope of application
This standard specifies the evaluation and classification standards for the burning performance of building materials. GB8624—1997
Replaces GB 8624--88
This standard applies to structural materials and various decorative and finishing materials used in various industrial and civil construction projects. 2 Referenced standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T2406-93 Test method for burning performance of plastics - oxygen index method GB/T2408-80 Test method for burning performance of plastics - horizontal burning method GB/T460984 Test method for burning performance of plastics - vertical burning method Determination of burning performance of textile fabrics - oxygen index method GB/T 5454-85
GB/T 5455--85
Determination of flame retardant properties of textile fabrics
Vertical method
GB/T5464--85 Test method for non-combustibility of building materials GB/T 8332-87
GB/T 8333--87
Test method for burning performance of foam plastics - horizontal burning method Test method for burning performance of rigid foam plastics - vertical burning method GB/T 8625~-88
Test method for flame retardancy of building materials
GB/T 8626--88
Test method for flammability of building materials
GB/T8627--88Test method for smoke density of burning or decomposition of building materialsHousehold washing and drying procedure for testing textilesGB/T 8629-88
GB/T11785--89Determination of critical radiant flux of floor coverings-Radiation heat source methodGB/T 1440293
3Test method for calorific value of combustion of building materials
GB/T14403-93
Test method for heat released by combustion of building materialsGrades and names of combustion performance of building materialsThe grades and names of combustion performance of building materials are shown in Table 1. Table 1 Class and name of combustion performance
Approved by the State Administration of Technical Supervision on April 4, 199728
Non-combustible materials
Flammable materials
Combustible materials
Flammable materials
Implemented on October 1, 1997
4 Non-combustible materials (Grade A)
4.1 Grade A homogeneous materials
GB 8624-- 1997
Tested according to GB/T5464, its combustion performance should meet the following requirements: a) The average temperature rise in the furnace does not exceed 50℃;
b) The average continuous burning time of the sample does not exceed 20s; c) The average mass loss rate of the sample does not exceed 50%. 4.2 Grade A composite (sandwich) materials
Materials that meet the following requirements are classified as Grade A in combustion performance. a) Tested according to GB/T8625, the average remaining length of each group of specimens is ≥35cm (the remaining length of any specimen is >20cm), and the average smoke temperature peak value of each test is <125℃, and there is no burning phenomenon on the back of the specimen; b) Tested according to GB/T8627, the smoke density level (SDR) is <15; c) Tested according to GB/T14402 and GB/T14403, the calorific value of the material is ≤4.2MJ/kg, and the heat release per unit area of ​​the specimen is ≤16.8 MJ/m;
d) The total non-lethal concentration LC of the toxicity of the material combustion smoke is ≥25mg/L. 5 Combustible materials (Grade B)
5.1 Grade B materials
Materials that meet the following requirements are rated as Grade BI for combustion performance. a) Tested according to GB/T8626, its combustion performance should meet the indicators specified in GB/T8626, and the phenomenon of burning dripping igniting filter paper is not allowed.
b) Tested according to GB/T8625, the average remaining length of each group of test pieces is ≥15cm (the remaining length of any one of the test pieces is 0cm), and the average flue gas temperature peak of each test is <200℃; c) Tested according to GB/T8627, its smoke density level (SDR) is ≤75. 5.2Bz grade materials
Tested according to GB/T8626, its combustion performance should meet the indicators specified in GB/T8626, and the phenomenon of burning dripping igniting filter paper is not allowed.
5.3B grade materials
Combustible building materials that do not belong to B1 and B2 grades have their combustion performance classified as B: grade. 6 Special provisions for certain materials for specific purposes This standard specifies the following corresponding test methods to determine the level of combustion performance for floor covering materials, curtain and drape textile materials, wire and cable casing plastic materials, and foam plastics used for pipe insulation, according to their use occasions. If the above materials are used as wall or ceiling materials, they should still be inspected and classified according to the provisions of Chapter 4 and Chapter 5. 6.1 Floor covering materials
The classification of combustion performance of floor covering materials is shown in Table 2. Table 2 Classification of combustion performance of floor covering materials
Test method
GB/T 11785
GB/T11785
6.2 Textile materials for curtains and drapes
Judgment index
Critical radiation flux ≥0.45W/cm2
Critical radiation flux ≥0.22W/cm2
Combustion performance level
GB 8624-1997
6.2.1 The classification of combustion performance of textile materials for curtains and drapes is shown in Table 3. Table 3 Grading test method for combustion performance of curtain and drape textile materials
GB/T 5454
GB/T5455
Judgment index
a) Damage length ≤150mm;
b) Afterflaming time ≤5s;
c) Smoldering time ≤5s;
d) Oxygen index ≥32
a) Damage length ≤200mm;Www.bzxZ.net
b) Afterflaming time ≤15ss
c) Smoldering time ≤10 s
d) Oxygen index ≥26
Combustion performance level
6.2.2 For curtain and drape textiles that have undergone permanent fireproofing treatment, the samples shall be washed and dried according to the method specified in GB/T8629 before the combustion performance test. The fabric washing procedure should be 5A, and the drying should be done in an oven. The burning performance grade of such textiles should be marked with "washable". 6.3 Plastic materials for wire and cable casings
The combustion performance classification of plastic materials for wire and cable casings is shown in Table 4. For wire and cable casing materials of the same material but different thicknesses, if the combustion performance of the materials with the maximum and minimum thicknesses simultaneously meet the requirements of a certain grade in Table 4, the materials with the middle thickness can also be confirmed as that grade. If the conditions cannot be met at the same time, the most unfavorable value shall be used as the basis for classification. Table 4 Combustion performance classification of plastic materials for wire and cable sheathing Material type
Thermoplastic plastics
Thermosetting plastics
Test method
GB/T 2406
GB/T2408
GB/T 8627
GB/T 2406
GB/T2408
GB/T 2406
GB/T 4609
GB/T8627
GB/T 2406
GB/T4609
6.4 Foam plastics for pipe insulation
Judgment indicators
a) Oxygen index ≥32;
b) Reach GB/T2408-80/1 level;
c) Smoke density level (SDR) ≤75
a) Oxygen index ≥26;
b) Reach GB/T2408--80/1 level
a) Oxygen index ≥32
b) Reach FV-0 level,
c) Smoke density level (SDR) ≤75
a) Oxygen index ≥26,
b) Reach FV-I level
Combustion performance level
For foam plastic products with a protective layer on the surface, the combustion performance shall be judged according to the requirements of Chapter 5. For foam plastic products without a protective layer on the surface, the classification of their combustion performance is shown in Table 5. For foam plastic products of the same material but different thicknesses, if the combustion performance of the materials with the maximum thickness and the minimum thickness simultaneously meet the requirements of a certain grade in Table 5, the material with the middle thickness can also be confirmed as this grade. If they cannot be met at the same time, the most unfavorable value should be used as the basis for classification. Table 5 Grading test method for combustion performance of foam plastics for pipeline thermal insulation
GB/T 2406
GB/T8333
GB/T8627
a) Oxygen index ≥32;
Judgment index
b) Average burning time ≤30s Average burning height ≤250mm; C) Smoke density grade (SDR) ≤75
Combustion performance level
Test method
GB/T 2406
GB/T8332
GB8624—1997
Table 5 (end)
Judgment index
a) Oxygen index ≥ 26;
b) Average burning time ≤ 90s, average burning range ≤ 50mm7 Special provisions for composite materials, surface coating materials, etc. Combustion performance level
7.1 For composite building materials produced in a standardized manner, regardless of their thickness or the production process, the combustion characteristics of the standardized products should be tested and comprehensively evaluated. 7.2 For coatings or other finishing layers (such as wallpaper) attached to the surface of interior decoration substrates by spraying, pasting or other methods on site, if the thickness is ≥ 0.6mm or the unit area mass is ≤ 300g/m2, the influence of the finishing layer on the combustion characteristics and classification of the substrate can be ignored. If the thickness of the facing layer exceeds 0.6mm or the facing has a significant effect on the combustion characteristics of the base material, the facing and the base material should be made into samples for testing and an overall comprehensive evaluation should be made.
7.3 For materials with fireproof surface treatment, the combustion performance classification should be tested and evaluated on the treated materials. The performance of fire-retardant coatings and flame retardants can be tested and evaluated in accordance with their relevant standards. Such tests and evaluations are not the basis and basis of this classification standard, but can be used as a reference for the comprehensive evaluation of its combustion characteristics classification. 8 Combustion performance classification mark
8.1 Building materials that are inspected in accordance with this standard and meet its provisions and requirements may be marked with the following marks according to their corresponding combustion performance levels:
GB8624A
GB8624B
GB8624B2
GB8624B3
8.2 For materials that are graded for combustion performance according to the special provisions of Chapter 6, the material name should be indicated in brackets after the mark level. For example, GB8624B, grade (paving materials), GB8624B2 grade (thermoplastics), etc. 3)
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