Shotfiring SWMS (Blast Initiation & Misfire Management)

Shotfiring covers the deliberate initiation of commercial explosives for rock breakage, demolition or excavation across surface quarries, underground mines and civil blasting projects. The work involves connecting initiation systems (NONEL, detonating cord, electric or electronic detonators), verifying circuit continuity, establishing fly-rock and air-overpressure exclusion zones, firing the shot, and managing any misfire before authorising re-entry. Every element of this task carries catastrophic energy release potential — a single premature detonation, stray current event or misjudged exclusion zone can fatally injure workers and members of the public. Under WHS Regulation 2025, blasting is classified High Risk Construction Work and explosives use is notifiable work under WHS Act s.38, meaning the PCBU must notify the WHS Regulator before each firing event and hold a documented SWMS reviewed by a licensed shotfirer prior to commencement. This SWMS captures the specific hazards, controls and licensing checks required to discharge that duty.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Elimination — Substitute electric detonators with electronic or NONEL shock-tube initiation systems wherever practicable to remove stray current and RF initiation pathways entirely.
2. 2Elimination — Prohibit any personnel within the calculated fly-rock exclusion zone during charging, tie-in and firing through physical lockout of access roads.
3. 3Substitution — Use bulk emulsion products in lieu of nitroglycerine-based explosives to reduce post-blast NOx fume generation and sensitivity to impact.
4. 4Engineering — Test initiation circuit continuity only with a manufacturer-approved blasting ohmmeter (intrinsically safe, current-limited) per AS 2187.2 Section 9 requirements.
5. 5Engineering — Establish redundant sentries, boom gates and audible warning sirens at exclusion zone perimeter with two-way radio confirmation before firing key is turned.
6. 6Administrative — Hold pre-blast briefing with licensed shotfirer (RIIBLA301E), confirm shot plan, exclusion radius and misfire procedure, then sign on this SWMS.
7. 7Administrative — Apply mandatory 30-minute wait after suspected misfire before any approach; secondary water drill per RIIBLA302E only by licensed shotfirer.
8. 8Administrative — Notify WHS Regulator and explosives authority of firing event under WHS Act s.38 and state Explosives Regulations prior to charging commencement.
9. 9PPE — Wear hi-vis, hard hat, safety glasses, hearing protection rated SLC80 ≥26 dB, and dust mask during charging and post-blast inspection activities.
10. 10PPE — Carry personal multi-gas monitor (CO, NO, NO2, O2) during post-blast re-entry with documented all-clear reading before crews are released to face.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

At a regional hard-rock quarry, a licensed shotfirer is preparing a 42-hole production blast on the upper bench. At the pre-start brief, the shotfirer opens this SWMS on a ruggedised tablet at the magazine and walks the charging crew, loader operator and two sentries through each section. Hazard 1 (premature detonation during continuity testing) is flagged: the shotfirer produces the approved blasting ohmmeter, shows its calibration sticker, and confirms the cheap multimeter in the ute will not be used. Exclusion zone is calculated at 380 metres using the AS 2187.2 fly-rock formula; sentries are positioned and radio-checked, and the SWMS sign-on sheet is countersigned by each worker. During charging, a sudden electrical storm warning is received on the BoM alert. The shotfirer pauses, re-opens the SWMS administrative controls section, and applies the suspend-and-retreat protocol — crews withdraw to the crib room, detonators are returned to the day box, and the firing window is rescheduled. After the storm clears, charging resumes, the shot is fired, and the 30-minute fume clearance wait is timed before a two-person inspection team re-enters with personal NOx and CO monitors, recording all-clear readings against the SWMS re-entry checklist before the loader is released to face.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• Code of Practice — Hazardous Manual Tasks

Frequently asked questions