Laboratory experiments show that the delay detonators, either electric (copper coated or aluminium) or non-electric (down-the-hole) as generally used in opencast mines and quarries have some scattering from the actual firing time due to manufacturing inaccuracy and variations in basic ingredients of the product. This scattering varies from 1 to 4 % depending on the product quality. Due to this component scatter, adverse blasting effects like misfires, overbreak, underbreak or fly-rock may occur if the design patterns are not judiciously made. It has also direct impact on muck profile and fragmentation. In this paper, it has been tried to correlate such impacts at varying component scatter of the system. A few useful and optimised design patterns are critically reviewed for scientific analyses. A number of useful findings are subsequently made for better utilisation of non-electric initiation systems.
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