Firing a relief hole

[Cpl_Carrott]

Took My shot firing & blast design exam couple of weeks ago,

think i may have failed on this question,
any pointers on how to word the answer would be appreciated

many thanks

CC

[Don T]

In drifting through rock You got your 'reliever' holes and your 'relief'
holes in a drill patern. The 'relief' hole is not loaded with powder and is
not 'fired' its purpose is to act as a free face for the rock to break to.
The number of 'relief' holes will depend on the design of the 'burn cut
round'.

DonT

Post by Cpl_Carrott
Took My shot firing & blast design exam couple of weeks ago,
think i may have failed on this question,
any pointers on how to word the answer would be appreciated
many thanks
CC