Relative effectiveness factor

The relative effectiveness factor, or R.E. factor, relates an explosive's demolition power to that of TNT, in units of the TNT equivalent/kg (TNTe/kg). The R.E. factor is the relative mass of TNT to which an explosive is equivalent; the greater the R.E., the more powerful the explosive.

This enables engineers to determine the proper masses of different explosives when applying blasting formulas developed specifically for TNT. For example, if a timber-cutting formula calls for a charge of 1 kg of TNT, then based on octanitrocubane's R.E. factor of 2.38, it would take only 1.0/2.38 (or 0.42) kg of it to do the same job. Using PETN, engineers would need 1.0/1.66 (or 0.60) kg to obtain the same effects as 1 kg of TNT. With ANFO or ammonium nitrate, they would require 1.0/0.74 (or 1.35) kg or 1.0/0.42 (or 2.38) kg, respectively.

The greater the R.E. number, the more powerful the explosive.

*: TBX (thermobaric explosives) or EBX (enhanced blast explosives), in a small, confined space, may have over twice the power of destruction. The total power of aluminized mixtures strictly depends on the condition of explosions.

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