The image shows an underground tunnel with a typical drill design applied to it. The following terminology is defined.
Shoulder hole: These refer to those holes immediately below the back perimeter holes.
Burncut: It consists of a group of blastholes arranged in a regular pattern around one or more uncharged relief holes. The first firing blasthole breaks both into the void offered by the uncharged relief holes and towards the free face provided by the tunnel face.
Easer: Hole adjacent to cut area.
Lifters: The blastholes along the bottom of the developed round. Proper performance of the lifters are essential in achieving good floor control.
Perimeter: blastholes Perimeter blastholes are those which form the boundary of
the tunnel. Explosive loading densities in these blastholes are generally lower than those in the remainder of the blast, as their prime requirement is to minimise back-breakage and provide a good contour.
Author: Dyno novel.