In recent years, construction and fire departments have required dense places such as subways, airports, high-rise buildings to use higher flame retardant levels of flame retardant B1 cables. Fire and flame retardant has become one of the important factors to consider when designing the integrated wiring scheme for all kinds of buildings.

In order to solve the problem of the lack of flame retardant classification standards in the cable industry for a long time and the imperfect assessment indicators in the original flame retardant standard system, the Ministry of Public Security introduced the EU CPR construction directive, and formulated the mandatory standard GB 31247-2014 "Cable and optical cable combustion Performance Classification" according to the actual needs of fire safety in China's construction projects. Released on December 5, 2014, and officially implemented from September 1, 2015, this is a real flame retardant grade classification standard that has been very hot for us in the past two years.

GB 31247-2014 On the basis of full investigation and verification tests, combined with the relevant requirements of EN 13501-6 and the actual grading assessment needs of cables and optical cables, the formation of A, B1, B2 and B3 four grades. Combustion performance indexes include main classification indexes such as combustion calorific value, flame spread, heat release, smoke production characteristics and smoke density.

Combustion performance Class A belongs to non-combustible materials, such components in the air under the action of open fire or high temperature, no fire, no micro-combustion, no carbonization. Common building materials: brick walls, steel roof truss, reinforced concrete and other components are non-combustible materials, generally mineral insulated cables. Combustion performance B1 class belongs to refractory materials, which are difficult to catch fire in the air or under the action of high temperature, difficult to ignite, difficult to carbonize, and when the fire source is removed, the combustion and micro-combustion immediately stop. B1 flame retardant is the highest grade of non-mineral insulated cables, which is between the B1a and B2a flame retardant grades of the European CPR.

Difference with traditional low-smoke halogen-free flame retardant cable

The difference between B1 flame retardant cables and traditional low-smoke halogen-free flame retardant cables is that B1 flame retardant not only considers the non-combustible performance of the cable body, smoke corrosion and light transmittance, but also includes the heat release process, smoke release process, combustion growth rate, combustion droplets and smoke toxicity during cable combustion.

Most of the modern construction are high-rise buildings. Once the high-rise building encounters a fire, the burning droplets or particles from the top fall to the bottom, which will accelerate the spread of the fire. In addition, according to the unique characteristics of the closed environment of the building itself, once the fire is caught, it is easy to cause the spread of the fire and the generation of toxic smoke. It not only threatens the life safety of personnel, but also causes greater difficulties for evacuation and rescue work.

Difference from bunch-burning stage B

B1 level flame retardant cable and we are familiar with the bunch-burning B level has nothing to do with B1 level flame retardant cable is not the classification of B level flame retardant cable. B1 level performance indicators contain low smoke, halogen-free, flame retardant, no burning droplets/particles, low toxicity and non-corrosive properties, while B level flame retardant only has flame retardant performance indicators.

Application prospect

10.2.2 of GB 55037-2022 clearly stipulates that "underground power cables and data communication cables in subway projects and power cables in urban integrated pipe gallery projects should use cables or flame-retardant wires with combustion performance not less than B1". GB 51348-2019 also clearly adopts the relevant combustion performance classification requirements in the GB 31247-2014 "Cable and optical cable Combustion performance classification" standard, and makes clear provisions on the combustion performance levels of cables installed in different types of buildings and places. B1 flame retardant cables are mainly used in the construction of fire prevention systems in subways, airports, shopping malls, hospitals, kindergartens, high-rise buildings and other places with dense doors and places requiring special protection. These places in the construction of fire codes are required to use a higher flame retardant level of the cable.

Flame-retardant B1 cable as a new type of flame-retardant cable, it is not only to assess the height of bunch-burning carbonization, but also to assess the heat release, smoke production characteristics of the cable, so to achieve the flame-retardant B1 cable combustion characteristics requirements (closer to the actual situation of the fire), for the cable material selection, structure and process requirements are more stringent, you must choose good materials, Reasonable process structure, rigorous process parameters.

Qingdao Tianxing Cable Co., Ltd. focuses on the production of customized wire and cable manufacturers, main: fire wire and cable, power cable, control cable 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