Abstract: A system is provided for initiating a blasting cap wherein pulsating light energy is converted to electrical energy. An optical coupler couples the source of energy to a remote firing arrangement to transfer the generated pulsating light energy to the firing arrangement. An electrical connection connects the firing arrangement to an ignition resistor in a detonator. Thus, the generated light energy is converted to electrical energy and is transferred to the ignition resistor, the transferred electrical energy being the firing energy for the ignition resistor.

Abstract: A field adjustable delay connector for use in detonating cord hook-ups for multi-charge blasting particularly adapted to work effectively with low energy shock or detonating cord. The delay connector is so constructed that the donor cord initiates combustion in a variable length of burning composition the length being mechanically adjustable by the blaster during hook-up.

Abstract: Low energy explosive shock tubing is provided which consists of a two-ply, inner and outer layer plastic tube having a plurality of lengthwise textile filaments bonded into the interface between the plastic layers. The textile filaments are chosen for their low elongation properties and the resultant shock tube resists stretching especially in warm borehole environments.

Abstract: A non-electric delay blasting method is provided which comprises the use of single trunk line of detonating cord having a series of detonating relays, all of the same delay period, connected at spaced intervals along its length. Branch lines of detonating cord are connected in groups to the trunk line in the intervals between the relays and each branch line has a delay detonator of the same delay period attached thereto. The delay period of the relays is shorter than that of the delay detonators. The detonators within the groups detonate in a random manner. The method eliminates the need to use large numbers of different delay period detonators in a multi-charge blast thus simplifying preparation of the charge and reducing inventories.