Chapter 8 BLAST DESIGN - NPS
Powder Factor = Tons of rock (or cubic yards) per pounds of explosive. Normal range = 4 to 7 Shallow holes = 1 to 2 External loads = .3 Tons of Rock = Powder Factor lbs of Explosives The higher the powder factor, the lighter the load. Lower powder factor means more explosives. Example: 1.5 tons = PF of 6.25lbs BURDEN-SPACING CALCULATION