The Scale Distance rule shows the relationship between ground vibration, maximum instantaneous charge and the distance.

The common format is

Where

V = vibration in mm/sec

k = ground transmission constant

D = distance from the blast to the monitor

Q = MIC

a = geological constant

The scale distance rule is used for vibration prediction.

Note that D/Q^0.5 is also known as the scale distance (SD).

A plot of log(PPV) against log(SD) can be used to determine k and a in the scale distance rule.