BCD type explosion-proof electric hoist wire rope according to GB3836-2000 the rules of the design, manufacture and test, explosion-proof marks for d Ⅱ BT4 and d Ⅱ CT4, apply to A level for the A and B Ⅱ Ⅱ, Ⅱ C level, temperature classes for T1 - T4 group of combustible gas, steam and air gas mixture formed by 1 zone and 2 zone place (see table 1).