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Subchapter 7. General Industry Safety Orders
Group 18. Explosives and Pyrotechnics
Article 116. Handling and Use of Explosives--Blasting Operations

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§5302. Permanent and Temporary Leading Wires.

(a) All leading wires shall be type "S" cable or equivalent, or shall consist of 2 suitable insulated solid aluminum or solid copper wires.

(b) Permanent leading wires shall be installed in conduit or shall be strung on insulators and kept at least 5 inches apart.

(c) The conductor used to close the air gap shall be type "S" cable or equivalent.

(d) All leading wires shall have the capacity to carry the required firing current to the detonators. In no case shall a capacity of less than copper wire No. 14 American Wire Gauge or aluminum wire No. 12 American Wire Gauge be used, except No. 18 American Wire Gauge may be used for one electric blasting cap.

Recommended power firing systems for series and parallel series firing with no
circuit interrupter.

Recommended power firing systems for series and parallel series firing using a
circuit interrupter.

(e) All splices shall be well made and shall be so joined as to be electrical and mechanically secure. Splices shall be taped or otherwise effectively insulated.

    Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.  

1. Amendment of subsection (d) and newNote filed 7-11-2003; operative 8-10-
2003 (Register 2003, No. 28).

2. Change without regulatory effect providing more legible illustrations filed
3-2-2009 pursuant to section 100, title 1, California Code of Regulations 
(Register 2009, No. 10).

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