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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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§5298. Blasting with Safety Fuse.

(a) Safety Fuse Initiation System.

(1) Safety fuses shall not be ignited before explosive charges are in place.

Exception: Avalanche blasting.

(2) When blasting with safety fuse, consideration shall be given to the following: (A) the length and burning rate of the fuse; (B) the condition of the escape route; and, (C) the distance to a place of safety.

(3) Safety fuses shall not be used in any location, such as a shaft, raise or winz, where the lack of adequate nearby shelter and the distance of travel to a place of safety is such that there is a hazard to employees from flying rock and concussion.

(4) All safety fuses shall be cut sufficiently long to extend beyond the collar of the hole and in no case shall they be less than 3 feet in length.

NOTE: At the usual rate of burning, a 3-foot length of safety fuse will fire a shot in about 2 minutes.

(5) Only single shots shall be fired when using 3-foot safety fuses. If more than one fuse is to be lighted at one time, such fuses shall comply with subsection (6) of this section.

(6) When lighting safety fuse, the fuses shall be so timed that no charge will detonate until at least 2 minutes after the last fuse in the blast area has been ignited.

(7) No one employee shall be permitted to ignite more than 12 safety fuses in succession. When 2 or more safety fuses in a group are lighted as one, by means of igniter cord or other fuse-lighting device, they may be considered as one fuse for the purpose of the subsection.

(8) If more than 3 safety fuses are lighted at one time, no person shall be permitted to enter the blast area until after a period of time equal to 2 minutes for each foot in the length of the longest fuse in the round or 15 minutes, whichever is the longest time.

(9) At least two employees shall be present when lighting fuses.

Exception: Avalanche blasting.

(10) Fuses shall be lit with devices approved for such purposes.

(b) Shock Tube Initiation System.

(1) Connections with other initiation devices shall be secured in a manner which provides for uninterrupted propagation;

(2) Factory-made units shall be used as assembled and shall not be cut except that a single splice is permitted on the lead-in trunkline during dry conditions; and

(3) Connections between blast holes shall not be made until immediately prior to clearing the blast site when surface delay detonators are used.


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


1. Amendment of section heading and section and new Note filed 9-24-97; operative 10-24-97 (Register 97, No. 39).

2. Repealer and new section heading and amendment of section filed 7-11-2003; operative 8-10-2003 (Register 2003, No. 28).

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