Abstract: A closed initiator system for explosives containing one or more non-electrically initiated blasting caps containing an ignition charge ignitable by action of explosive energy of an explosive gas mixture, including means for removal of resident non-explosive gases from the blasting cap(s) to provide space for the explosive gas mixture and subsequent emplacement of the explosive gas in the blasting cap(s) for explosion and responsive ignition of the ignition charge. Means for removal of the resident non-explosive gases include evacuation means and gas displacement means. Method involving initiation of one or more of the blasting caps disposed in gas-tight relationship is also provided.

Abstract: A nonelectric blasting cap initiated by thermal detonation energy from an explosive gas mixture, in which the required open space for charging and detonating the explosive gas mixture is contained, together with the conduit means, in an end closure member; and the open space is shaped to provide a shell to end closure crimp without impairing flow of explosive gas through the conduits.A blasting system including a plurality of the above blasting caps is also provided.