“ZB” stands for “Flame Retardant Class B. PVC is a plastic cover that protects the wire. Traditional Bundled Flame Retardant ZA, ZB, ZC and ZD Classes do not belong to the classification of flame retardant performance. The flame retardant levels of ZA, ZB, ZC, and ZD refer to GB/T 19666-2019 “General Rules for Flame Retardant and Fire Resistant Wires, Cables, or Optical Cables”, which. Flame-retardant cables refer to the characteristic that the cable is burned under the specified test conditions. After the fire source is removed, the flame spread on the cable is only within a limited range and extinguishes itself, that is, it has the ability to prevent or delay the occurrence or. Cable models are typically represented by a combination of letters and numbers, each indicating different properties. -. However, the diverse flame - retardant grade labels on the market, such as "B1 grade", "ZB", "ZA", "WDZB", etc., have confused many engineers and even purchasers. What exactly do these labels mean? Can they be used interchangeably? Today, we will thoroughly clarify two frequently - occurring but. ZR is the meaning of flame retardant, flame retardant A, B, C three, ZB on behalf of B-class flame retardant, ZR default C-class flame retardant. Applicable to. If you work in construction or electrical trade, you might see the term “ZB-AVRB Cable. This guide breaks it down for you.