Blasters' Handbook

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1918 Excerpt: ... Electric Blasting Caps and electric firing are used the same care must be taken with regard to safety before the wires are connected to the blasting machine or electric switch. When the blaster is assured that everything is all right, the connections are made and the blast fired. In case of a failure of the blast to go when using Electric Blasting Caps the blaster is safe in disconnecting his wires and returning immediately to look for the trouble. When using fuse and Blasting Caps it is not safe to return to look for the cause of a failure until a considerable time has elapsed--preferably several hours. This matter of waiting is an additional argument for the use of Electric Blasting Caps instead of Blasting Caps for almost all classes of blasts. After a blast is fired the blaster should wait a sufficient length of time to allow the falling matter to drop, and for the smoke, fumes and dust to be partially dissipated or blown away. Handling a Misfire.--The use of high grade explosives and detonators and careful loading will reduce the dangers of shots failing to fire. When a misfire does occur the blaster should be governed by conditions. When electric blasting caps are used and one or all of the holes fails, disconnect the wires from the blasting machine, then it is safe to go back immediately to investigate the trouble. The investigation should first consist of a search for broken wires, faulty connections or short circuits. If such are found, make the proper repairs, reconnect the leading wires and operate the blasting machine. Many so-called failures are the result of poor connections or connections being in contact with wet ground, or other conductive material. When caps and fuse are used greater care must be exercised. It is never safe to go back imm...