Abstract: An initiation fixture (16) for an impulse transmission tube comprises a sleeve (30) having an internal longitudinal bore. The sleeve (30) is dimensioned and configured to receive a shock tube (10) in one end and a primer cap (28) in the other. An internal fence (32) establishes a touch hole (33) between the primer cap (28) and the end of the shock tube (10). In addition, primer cap (28) and the end of shock tube (10) are separated by an intervening isolation member (34) which disperses static electricity from shock tube (10) to prevent discharge across touch hole (33) to primer cap (28). A retainer means (40) is movably disposed on an exterior surface of sleeve (30) and is dimensioned and configured to engage a triggering device (18). A first stop means (42) allows retainer (40) to secure the end of sleeve (30) within the triggering device (18) and positions primer cap (28) for detonation by a striking pin (20).

Abstract: A plurality of discrete transmission tubes are held in axially extending juxtaposed relation by an outer sheath which coextensively covers the tubes. An axially extending line of weakness is formed along the length of the sheath. The transmission tubes may be simultaneously initiated for redundent transmission of an initiation signal.