Drilling And Blasting - Study Mode

[#516] The safe working period of BG 174 is . . . . . . . . in hard work.
Correct Answer

(B) 4 hrs

[#517] Boundary ventilation system is possible where the D.C and U.C shafts located at . . . . . . . . ends of property and the air from the intake and return side is practically eliminated.
Correct Answer

(B) Opposite

[#518] Which of the following statements seems to be correct in relation to detonators?
Correct Answer

(C) Detonators of same electrical resistance only be used

[#519] Lower limit of methane air mixture.
Correct Answer

(C) 5.4

[#520] The diameter of sampling pipe in fire stopping is
Correct Answer

(C) 18 mm