7 Colo. Code Regs. § 1101-9-6-3

Current through Register Vol. 47, No. 20, October 25, 2024

Section 7 CCR 1101-9-6-3 - Electric Initiation of Blasts

(A) Electric detonators may be used for blasting operations in congested districts, or on highways, or adjacent to highways open to traffic, except where sources of extraneous electricity make such use dangerous.

(B) Electric detonator wires shall be kept short-circuited (shunted) until they are connected into the circuit for firing.

(C) Signs shall be posted warning against the use of mobile radio transmitters on all adjacent highways and roads.

(D) Mobile radio transmitters that are less than 100 feet away from electric detonators shall be de-energized and effectively locked when the detonators are not in the original containers.

(E) Electric detonators shall be used in compliance with the recommendations of IME with regard to blasting in the vicinity of radio transmitters as stipulated in Safety Guide for the Prevention of Radio Frequency Radiation Hazards in the Use of Commercial Electric Detonators (Blasting Caps), IME Safety Library Publication No. 20, December 2011.

(F) Precautions in accordance with the recommendations of IME with regard to blasting in the vicinity of radio transmitters as stipulated in Safety Guide for the Prevention of Radio Frequency Radiation Hazards in the Use of Commercial Electric Detonators (Blasting Caps), IME Safety Library Publication No. 20, December 2011 shall be taken to prevent accidental discharge of electric detonators from current induced by radar, cellular telephones, radio transmitters, battery contact, lightning, adjacent power lines, static electricity, dust storms, blowing snow or other sources of extraneous electricity.

(G) Before adopting any system of electrical firing, the blaster shall conduct a thorough survey for extraneous currents, and all dangerous currents shall be eliminated before any holes are loaded.

(H) In any single blast using electric detonators, all detonators shall be of the same style or function and be of the same manufacture.

(I) Electric blasting shall be carried out by using blasting circuits or power circuits, in accordance with the electric detonator manufacturer's recommendations.

(J) The firing line shall be checked with an approved testing device at the terminals before being connected to the blasting machine or other power source.

(K) The circuit, including all detonators, shall be tested with an approved testing device before being connected to the firing line.

(L) When firing a circuit of electric detonators, care shall be exercised to ensure that an adequate quantity of delivered current is available, in accordance with the manufacturer's recommendation.

(M) Connecting wires and lead wires shall be insulated single solid wires of sufficient current- carrying capacity and shall not be less than #20 gauge (American wire gauge) solid core insulated wire.

(N) Firing line or leading wires shall be solid single wires of sufficient current carrying capacity, and shall be not less than #14 gauge (American wire gauge) solid core insulated wire. Bus wires depend on the size of the blast, but #14 gauge (American wire gauge) copper is recommended.

(O) The ends of lead wires which are to be connected to a firing device shall be shorted by twisting them together or otherwise connecting them before they are connected to the leg wires or connecting wires, and they shall be kept in the possession of the person who is doing the loading until loading is completed and the leg wires attached. Lead wires shall not be attached to the firing device until the blaster is ready to fire the shot and must be attached by the blaster.

(P) The ends of the leg wires on electric detonators shall be shorted in a similar manner and not separated until all holes are loaded and the loader is ready to connect the leg wires to the connecting wires or lead wires.

(Q) When firing electrically, the insulation on all firing lines shall be adequate and in good condition.

(R) A power circuit used for firing electric detonators shall not be grounded.

(S) When firing from a power circuit, the firing switch shall be locked in the open or "off" position at all times, except when firing. It shall be so designed that the firing lines to the cap circuit are automatically short-circuited when the switch is in the 'off' position. Keys to this switch shall be entrusted only to the blaster.

(T) Blasting machines shall be in good condition and the efficiency of the machine shall be tested periodically to make certain that it can deliver power at its rated capacity.

(U) When firing with blasting machines, the connections shall be made as recommended by the manufacturer of the electric detonators used.

(V) The number of electric detonators connected to a blasting machine shall not be in excess of its rated capacity. A series or circuit shall contain no more detonators than the limits recommended by the manufacturer of the electric detonators in use.

(W) The blaster shall be in charge of the blasting machines, and no other person shall connect the leading wires to the machine.

(X) Blasters, when testing circuits to charged holes, shall use only blasting testers especially designed for this purpose.

(Y) In electrical firing, only the person making leading wire connections shall fire the shot. All connections shall be made from the borehole back to the source of firing current, and the lead line wires shall remain shorted and not be connected to the blasting machine or other source of current until the charge is to be fired.

(Z) After firing an electric blast from a blasting machine, the leading wires shall be immediately disconnected from the machine and short-circuited.

(AA) When electric detonators have been used, workers shall not return to misfired holes for at least thirty minutes.

7 CCR 1101-9-6-3

38 CR 03, February 10, 2015, effective 3/10/2015

41 CR 21, November 10, 2018, effective 12/1/2018

42 CR 06, March 25, 2019, effective 5/1/2019