About: Hopkinson-Cranz Scaling Law

The Hopkinson-Cranz rule allows the scaling of blast data using the cube root law.  

Given a coefficient, Z, the equations for this calculation are as follows:

         Range = Z * Weight1/3

         Weight = (Range / Z)3

Hopkinson-Cranz Scaling Law

Many States use rules based upon the explosives, their quantity, and the distance from the explosive to where people are at risk. These rules are known as Quantity-Distance (Q-D) criteria, and are based on the approach derived from the Hopkinson-Cranz Scaling Law, which is further amended by a range of coefficients. It is the basis of much of the work on the estimation of appropriate quantity and separation distances.

Scaled distance coefficient (m/kg1/3):
Range (m)
Scaled distance coefficient(m/kg1/3):
Weight of explosive (kg)