The specific rule I am referring to:
9.3 Break Box
On every break shot, the cue ball must be shot from within the confines of the "break box". This box is defined as an area extending nine inches to the left and to the right of the head spot along the head string, then extending two perpendicular lines from the head string to the head rail creating an area 18" by 25". If the table is not marked at nine inches then the two diamonds on the head rail define the box. Failure to shoot the cue ball from within this area on the break shot is a foul. |
