2. What does the burden measure on each hole?
This is a requirement of the Quarries Regulations.
Measurements must be taken in order to establish the burden on any hole is to a free face. This will require measurements on both the face and down hole.
These are used to determine burdens within tolerances and identify any weak burdens. Weak burdens do not have to be in front of the hole, they can the side.
These are use alongside og and the face inspection in order to the dr identify other weaknesses.
Commonly this is carried out via a Laser Profile but could be determined by Stereo Photogrammetry