California Code of Regulations › Title 8 - Industrial Relations › Division 1 - Department of Industrial Relations › Chapter 4 - Division of Industrial Safety › Subchapter 7 - General Industry Safety Orders › Group 18 - Explosive Materials › Article 116 - Handling and Use of Explosive Materials in Blasting Operations › Section 5299 - Firing with Electricity-General

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a) Before adopting any system of electrical
						firing, the licensed blaster shall conduct a thorough survey for extraneous
						currents, and all dangerous currents shall be eliminated before any holes are
						loaded. No electric blasting or preparation for electric blasting shall be done
						when stray electrical currents exceed 0.05 amperes.
EXCEPTION: Specialty electric blasting caps used as
						  recommended by the manufacturer.
(b) Electric firing shall be done only with
						devices designed for initiating electric detonators.
(c) Electric detonators to be fired with
						blasting machines shall be connected in accordance with the number and
						circuitry limitations recommended by the machine or detonator
						manufacturer.
(d) Devices used for
						igniting electric detonators shall not cause arcing in the detonators. A
						circuit interrupter shall be used when arcing is a problem.
(e) All blasting wires shall be kept clear of
						electric lines, pipes, rails, and other conductive materials.
(f) That part of the blasting circuit leading
						from the firing switch to the blast area shall not be grounded.
(g) All low-voltage electric power lines
						within 50 feet of the holes to be loaded shall be removed or de-energized
						before an electric detonator or starter is brought into the blast area. Where
						this is not practical, a check for stray current shall be made with a proper
						instrument.
(h) The blasting
						circuit shall be tested with a blasting galvanometer or other device designed
						to test blasting circuits before firing the round.
(i) The blasting circuit shall remain shorted
						until the round is ready to test and fire.
(j) Electric detonators of different brands
						shall not be used in the same round.
(k) Where light and power circuits are used
						for blasting, keys to the shot-firing and safety switches shall be kept by the
						licensed blaster. When necessary to make repairs, extensions, or tests on the
						blasting or shot-firing lines, the licensed blaster or blaster in training
						shall unlock and remain at the switch until he or she relocks the switches or
						designates that responsibility to someone who reports back to the licensed
						blaster with the keys when work is completed. No preparations for loading or
						blasting shall be done until all switches are relocked and the keys back in the
						possession of the licensed blaster. At the end of the shift, the licensed
						blaster shall give the keys to the licensed blaster of the following shift. A
						duplicate set of keys should be kept by the superintendent under lock and key
						in the office. There shall be no other set of keys fitting these locks on the
						job site.
(l) Mobile radio
						transmitters shall be de-energized and effectively locked when less than 100
						feet from electrical blasting caps that are not in their original container.
EXAMPLES OF BLASTING CIRCUITS
Electric Detonators
Click
						  here to view image
1.
						  Amendment of subsection (c) filed 3-28-75; effective thirtieth day thereafter
						  (Register 75, No. 13).
2. Amendment of subsection (a) filed
						  10-17-75; effective thirtieth day thereafter (Register 75, No.
						  42).
3. Repealer of subsection (a) and relettering of existing
						  subsections filed 3-7-80; effective thirtieth day thereafter (Register 80, No.
						  10).
4. Amendment filed 7-11-2003; operative 8-10-2003 (Register
						  2003, No. 28).
5. Change without regulatory effect providing more
						  legible diagrams filed 3-2-2009 pursuant to section
						  100, title 1, California Code of
						  Regulations (Register 2009, No. 10).
Note: Authority cited: Section
							 142.3, Labor
							 Code. Reference: Section
							 142.3, Labor
							 Code.