兼做回风井的装有带式输送机的井筒,甲烷传感器报警浓度、断电浓度、复电浓度分别是()。
A≥0.5%CH4,≥0.7%CH4,<0.7%CH4
B≥0.5%CH4,≥0.5%CH4,<0.5%CH4
C≥1.5%CH4,≥1.5%CH4,<1.5%CH4
D≥1.5%CH4,≥2.0%CH4,<1.5%CH4
A≥0.5%CH4,≥0.7%CH4,<0.7%CH4
B≥0.5%CH4,≥0.5%CH4,<0.5%CH4
C≥1.5%CH4,≥1.5%CH4,<1.5%CH4
D≥1.5%CH4,≥2.0%CH4,<1.5%CH4