Danger Zones
All blasting operations must have a declared danger zone. The Danger Zone should extend beyond the expected spread of the blast with a significant margin of safety included. The extent of the danger zone should be shown on a plan of the quarry and included in the Blast Specification. The danger zone may extend outside of the quarry boundary.
The danger zone needs to be controllable and should only use a limited number of entry
points that can be guarded.
Sentries must be able to see / control all parts of the danger zone that they are responsible for.
The danger zone should be as large as reasonably possible and should ensure that materials from the blast are not projected beyond it. If there is any doubt that the danger zone is adequate then the danger zone should be enlarged.
Both the Explosives Supervisor and Shotfirer need to agree on the required danger zone.
The arrangements for establishing danger zones and evacuating danger zones, the provision of appropriate warning systems and posting of sentries should be documented in the shotfiring rules.
It is the responsibility of the Explosives Supervisor to check that the danger zone likely to be created by the firing of each shot has been determined, that effective measures are in place to evacuate and control the danger zone and that there is provision of effective shelters when a shot is tested or fired.
If the Shotfirer cannot conform to the specification for the danger zone or if it appears to be different from that shown, shotfiring operations should be suspended until any change to that specification has been authorised by its author or other designated person such as the Explosives Supervisor.
The Shotfirer must ensure that an adequate danger zone is established, cleared and sentries appointed to prevent inadvertent access; and ensure that the shot is fired from a safe place.
Sentries are there to prevent persons from entering the danger zone and must not leave their post until the all clear signal has been given, or until released by the person that appointed them.
The Shotfirer must inspect following the blast to ensure that all the shotholes have fired and that no misfires have occurred and to ensure that the quarry face and sides are in a safe condition and establish that material did not project beyond the danger zone.
The Shotfirer shall not allow persons to enter the danger zone until the all clear signal is given and they consider it safe for them to do so.