Flame retardant cable coatings are applied to grouped electrical cables as a passive protection means to reduce the fire hazard. This work studied the flammability of cable coatings and developed a fire test method to evaluate the fire propagation propensity of grouped cables protected by cable coatings. Firstly, ignition tests of 12 cable coatings were conducted and showed that all cable coatings are ignitable. Secondly, three selected cable coatings and a cable bandage, as an alternative passive protection method, were evaluated along with two types of electrical cables in ASTM E‐2058/ISO 12136 by measuring the fire propagation index (FPI). The FPI values of coated cables do not demonstrate a monotonous change relative to the FPI of uncoated cables, and the FPI trend is cable dependent. Thirdly, two selected cable coatings and a cable bandage were further examined in the 2.4‐m parallel panel fire test (PPT) along with an electrical cable with an FPI value of 30 (m/s^1/2)/(kW/m)^2/3. The cables coated by both tested cable coatings showed fire propagation while the bandaged cables did not propagate. The consistent fire propagation propensities between the PPT and small‐scale fire tests support using the FPA tests to examine the flammability of cable coatings.

中文翻译：

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被动保护对电缆火势蔓延的影响

阻燃电缆涂层作为一种被动保护手段，可应用于成组的电缆，以减少火灾隐患。这项工作研究了电缆涂层的可燃性，并开发了一种耐火测试方法，以评估受电缆涂层保护的成组电缆的火势蔓延。首先，对12个电缆涂层进行了点火测试，结果表明所有电缆涂层都是可燃的。其次，在ASTM E-2058 / ISO 12136中，通过测量火蔓延指数（FPI），对三种选择的电缆涂层和电缆绷带（作为一种替代的被动保护方法）以及两种类型的电缆进行了评估。涂层电缆的FPI值相对于未涂层电缆的FPI不会表现出单调变化，并且FPI趋势取决于电缆。第三，^1/2）/（kW / m）^2/3。两种测试的电缆涂层都覆盖的电缆显示出火焰蔓延，而绷带的电缆则不蔓延。PPT和小规模火灾测试之间的一致的火灾蔓延倾向使用FPA测试来支持检查电缆涂层的可燃性。