[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.