Blasting, Explosives and Drilling Operations
The blasting team
Explosives work is tightly controlled. The shotfirer is the competent, appointed person in charge of the shot; only appointed and authorised people handle explosives. Explosives are stored in licensed magazines, issued and returned with records kept, and transported according to the rules. Questions often test that the shotfirer's authority is absolute during charging and firing.
The blast sequence
Drilling to the designed pattern, checking hole depth and spacing, charging, stemming, connecting, clearing the area, sounding warnings, firing, and then inspecting the face before anyone returns. Exclusion zones and sentries must be in place before firing; warning signals (audible and visual) are given in a defined sequence. A misfire is never investigated immediately - the area is kept clear for the defined waiting period before the shotfirer approaches.
Drilling
Drilling creates dust (silica) and noise: use dust suppression or extraction, hearing protection, and keep clear of rotating parts. Never drill into a misfired hole or a hole containing explosives residue. Check for butts and cavities.
Traps
- "Everyone knows the signal" is not a control - sentries and physical exclusion are.
- A misfire is not a "try again" situation; follow the defined procedure and waiting time.
- Explosives records must be accurate and auditable.
Worked example
After firing, a sentry reports the count is short. The shotfirer keeps everyone out, waits the defined period, then approaches alone to inspect and deal with the misfire per procedure.