What is B1 flame retardant wire and cable?

In fact, ZB and B1, B2 are completely different nature of the cable, with the high-rise buildings and electrical equipment more and more, electrical safety standards are gradually improving, B1 flame retardant wire and cable, will more and more appear in engineering applications.

1. Different criteria for reference

ZB flame retardant level refers to GB/T 19666-2019 "Flame retardant and fire-resistant wire and cable or optical cable General Rules", according to the combustion characteristics are divided into ZA, ZB, ZC, ZD four grades;

The B1 flame retardant level refers to GB 31247-2014 "Combustion Performance Classification of cables and optical cables", which is divided into A, B1, B2 and B3 according to the flame spread length, peak heat release during combustion, total heat release, combustion speed, peak smoke generation speed, total smoke generation in 20min, smoke concentration and other indicators.

2, the standard binding force is different

GB 31247 "Cable and optical cable combustion performance classification" is a national mandatory standard, mandatory binding, do not meet the mandatory standards shall not be produced, sold, imported. GB/T 19666-2019 "Flame-retardant and fire-resistant wire and cable or optical cable General Principles" is a recommended standard that Guojia encourages the use of. Mandatory standards are unified standards throughout the country, standards to protect human health, personal and property safety and national standards to be enforced by laws and administrative regulations; Recommended national standards are voluntary standards, mainly for production, inspection, use and other aspects.

3. Different technical requirements

What is important is the technical requirements of B1 flame retardant wire and cable, from which you can clearly understand the performance of these indicators in terms of safety performance.

Standard for combustion performance

1. Flame spread FS≤ 1.5m;

2. Peak heat release rate ≤30 kW; The total heat release within 1200 s under fire is less than 15 MJ;

3, combustion growth rate index FIGRA≤150 W/s;

4. Peak smoke production rate ≤ 0.25m2 /s; The total amount of smoke produced within 1200 s under fire is less than 50 m2

5, smoke density (minimum transmittance) It≥ 60%

6, vertical flame spread H≤ 425mm products must provide 3 additional information

1) Drop level: The combustion drop/particle level is divided into d0, d1, d2 three levels

2) Flue gas toxicity level: According to the damage/damage degree caused by toxic and harmful substances in the flue gas, it is divided into: t0, t1 and t2

3) Corrosion grade: According to the surrounding medium corrosion ability of the material is divided into a1, a2, a3 three grades

Special attention

B1, B2 flame retardant products must indicate additional information; For example: GB 31247 B1(d0, t0, a1), if not marked, it is regarded as B3 flame retardant products, that is, ordinary low-smoke halogen-free wire and cable.

B1 flame retardant wire and cable application

GB 51348-2019 "Standard for Electrical Design of Civil Buildings" When using direct wiring in indoor places, the following provisions shall be met:

1, should use no less than B2 flame retardant sheath insulated wire, its cross-sectional area should not be greater than 6mm;

2, fire-resistant cable and mineral insulated cable wiring, fire-resistant cable and mineral insulated cable should have no less than B1 fire-resistant performance

The selection and laying of fire distribution lines should meet the requirements for the continuous operation time of fire fighting electrical equipment (750 ° C, 90min) and comply with the following provisions:

1. The alarm bus of the automatic fire alarm system in the evacuation channel in densely populated places should choose the B1 level cable of combustion performance;

2, the alarm bus in other places should choose the combustion performance of not less than B2 cable;

3, fire linkage bus and linkage control line should choose refractory copper core cable; Combustion performance shall comply with the provisions of GB 31247;

Qingdao Tianxing Cable Co., Ltd. focuses on the production of customized wire and cable manufacturers, main: fire wire and cable, power cable, control cable, computer cable, BV wire and other products, exported to more than 40 countries and regions around the world, the annual production capacity of 1 billion yuan. 6000 square meters of storage, standing hundreds of millions of inventory, order demand for rapid distribution and delivery, large prices more favorable. Hotline: 16678668098