4.6.12. Electric blasting operations:(a) For electritc blasting operations, the entire length of the lead wires must be made of 2 insulated conductors that do not come in contact with the ground or other conductor and must reach the immediate vicinity of the firing point. These conductors must not be intertwined with conductors intended for any other purpose whatsoever, nor run in the same tube with them, nor have the possibility of coming in contact with them;
(b) To avoid stray electric currents or current leaks to ground, bare connections between the lead wires and the cap leg wires or between the cap leg wires must not come in contact with the ground or equipment.