Aramid makes fire extinguishing suit no longer spontaneous

A few days ago, in the fire in Jianli, Hubei Province, a firefighter had to jump off the building to escape because of the fire. How fire-fighting suits do not ignite spontaneously has once again become a hot topic in the industry.

Flame retardancy is the most basic performance requirement for fire fighting suits. Extending the high temperature resistance time of the fire-fighting suit fabric and the time of leaving the burning material has always been a difficult problem to be overcome.

In fact, all countries have clear regulations on the time after the fire-retardant fabric leaves the burning material. The AS64 (American Society for Testing and Materials) release of the D6413 "Textile Fire Resistance Standard Test Method (Vertical Test Method)" technical specification, the European flame propagation test standard EN 532 clearly stipulates that the fire-fighting suit fabric must be within 2 seconds of leaving the flame Extinguished. China's "Fireman's Fire-fighting Protective Clothing" industry standard (GA10-2014) also stipulates that fire-fighting suits should be extinguished within ≤ 2 seconds. Obviously, the fire-fighting protective suit in Jingzhou fire was ignited by the fire, and its continuous burning time is not in line with the national requirements for fire-resistant fabrics. However, this is not an accidental phenomenon, and firefighters' fire-fighting suits spontaneously occur.

At present, domestic fire-fighting suits are generally composed of an outer layer, a waterproof and breathable layer, a heat-insulating layer, and a comfortable layer of multi-layer fabric. Among them, the outermost layer is a layer directly in contact with the flame, and is also the most critical layer related to the quality of the product. Most of the outer fabrics of the existing domestic fire-fighting suits are flame-retardant treatments carried out in the finishing process to achieve non-combustible purposes, and the production process is long and the process cost is high. However, the finishing flame retardant treatment is often difficult to achieve good results in terms of afterburning time. Therefore, it is imperative to develop low-cost flame-retardant fabrics.

The development and application of aramid fabrics makes it possible for fire extinguishing suits to no longer spontaneously ignite. From the technical point of view, aramid fiber itself is a flame retardant fiber, so the flame retardant and high temperature resistance of the aramid fabric is naturally superior. The test results show that the aramid fabric can be used for a long time in a high temperature environment of 200 ° C. When the temperature exceeds 400 ° C, the phenomenon of droplets and flame retardation does not occur. Although the aramid fabric will gradually become brittle and charred until the external temperature reaches 800 ° C or above, there is still no open flame.

In particular, it is worth mentioning that once the aramid fabric leaves the fire source, it will quickly extinguish itself. At present, Taimeida Aramid developed by Yantai Taihe New Materials Co., Ltd. can achieve zero-second flameout.

However, the promotion of a relatively high cost aramid fabric in the field of fire protection still has some difficulties. The industry generally believes that the state's policy of standardizing the performance of fire protection clothing with high standards and strict requirements is the best way to accelerate the promotion of aramid fire fighting clothing.