[Code of Federal Regulations]

[Title 30, Volume 1]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 30CFR57.6501]



[Page 361]

 

                       TITLE 30--MINERAL RESOURCES

 

  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR

 

PART 57_SAFETY AND HEALTH STANDARDS_UNDERGROUND METAL AND NONMETAL MINES

--Table of Contents

 

                          Subpart E_Explosives

 

Sec.  57.6501  Nonelectric initiation systems.



    (a) When the nonelectric initiation system uses shock tube--

    (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 blastholes shall not be made until 

immediately prior to clearing the blast site when surface delay 

detonators are used.

    (b) When the nonelectric initiation system uses detonating cord--

    (1) The line of detonating cord extending out of a blasthole shall 

be cut from the supply spool immediately after the attached explosive is 

correctly positioned in the hole;

    (2) In multiple row blasts, the trunkline layout shall be designed 

so that the detonation can reach each blasthole from at least two 

directions;

    (3) Connections shall be tight and kept at right angles to the 

trunkline;

    (4) Detonators shall be attached securely to the side of the 

detonating cord and pointed in the direction in which detonation is to 

proceed;

    (5) Connections between blastholes shall not be made until 

immediately prior to clearing the blast site when surface delay 

detonators are used; and

    (6) Lead-in lines shall be manually unreeled if connected to the 

trunklines at the blast site.

    (c) When nonelectric initiation systems use gas tube, continuity of 

the circuit shall be tested prior to blasting.