Drill-and-Blast Tunnelling SWMS
Drill, charge, blast, muck-out cycle in hard rock tunnelling. RCS at the 0.05 mg/m³ WES (transitioning to lower WEL Dec 2026), DPM, blast vibration, post-blast re-entry atmosphere, rock support.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Drill and blast tunnelling excavates a tunnel by drilling a pattern of holes into the face, charging them with explosives, and blasting to break the rock, then mucking out the broken rock and supporting the ground before the next cycle. It combines the severe hazards of underground tunnelling — ground instability, a confined and potentially contaminated atmosphere, restricted egress, respirable crystalline silica and diesel particulate — with the hazards of explosives: premature initiation, flyrock and air overpressure in the confined heading, misfires that leave live charges in the face or muckpile, and toxic post-blast fumes that must be cleared before re-entry. This document is written on the basis that drill and blast tunnelling is carried out in a controlled cycle by competent, licensed personnel, with the explosives and the ground both managed as critical hazards.
Drill and blast tunnelling engages several high risk construction work categories under the model Work Health and Safety Regulations — work involving a tunnel, work in or near a confined space, work in a contaminated or flammable atmosphere, and the use of explosives — so a safe work method statement is required before the work commences, kept readily accessible, and given to the principal contractor if one is appointed. The explosives are additionally regulated under the explosives legislation. Where the rock is silica-bearing, drilling and processing it is high-risk processing of a crystalline silica substance, and diesel particulate from underground plant is controlled against its standard. This document coordinates the ground-support, ventilation, silica, explosives and re-entry controls so the tunnel is advanced without a ground failure or an explosives incident.
Hazards identified
9 hazards covered, sorted by priority.
Fatal crushing of workers from unsupported or failing ground
Detonation while workers are present in the heading
Impact injury and overpressure effects in the restricted space
A live, unstable charge endangering mucking and the next drill cycle
Poisoning where workers re-enter before fumes are cleared
Silicosis and respiratory disease from sustained underground inhalation
Carcinogenic diesel exhaust exposure compounding the dust burden underground
Asphyxiation, poisoning or explosion in the confined underground atmosphere
Delayed escape and entrapment if conditions deteriorate underground
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Engineering: a ground-support and ground-control system designed by a competent person for the ground conditions, installed in a controlled sequence so workers are not under unsupported ground, with monitoring of ground behaviour.
- 2Engineering: forced underground ventilation designed to dilute and remove respirable crystalline silica, diesel particulate, dust and other contaminants and maintain a safe atmosphere, with continuous atmospheric monitoring.
- 3Engineering: control respirable crystalline silica at the source — wet drilling and cutting, water suppression and dust capture — supported by ventilation, to keep airborne silica below the exposure standard, monitored against the respirable crystalline silica workplace exposure standard of 0.05 mg/m3 (eight-hour TWA), reframed as a workplace exposure limit from 1 December 2026.
- 4Administrative: a defined drill, charge, blast and re-entry cycle, with the blast designed by a competent person for the confined heading, a licensed shotfirer, and compliance with the explosives legislation for licensing, storage and security.
- 5Administrative: a misfire-management procedure — identification, marking, exclusion and the defined method of dealing with a misfire — and a check for misfired or live charges before drilling the next round.
- 6Administrative: post-blast re-entry only after the ventilation has cleared the toxic fumes and the atmosphere is confirmed safe, with the heading ventilated before re-entry.
- 7Engineering: low-emission or filtered underground plant and ventilation to control diesel particulate matter, monitored against the diesel particulate matter exposure standard, currently 0.1 mg/m3 (eight-hour TWA, sub-micron elemental carbon), with a Workplace Exposure Limit of 0.01 mg/m3 (respirable elemental carbon) from 1 December 2026.
- 8Administrative: prepare a SWMS before the work for the tunnel and confined space high risk construction work, apply the confined space entry and atmospheric controls and permits, and where the work is high-risk processing of a crystalline silica substance, a silica risk control plan with air and health monitoring.
- 9Administrative: air monitoring for respirable crystalline silica against the respirable crystalline silica workplace exposure standard of 0.05 mg/m3 (eight-hour TWA), reframed as a workplace exposure limit from 1 December 2026, and for diesel particulate, dust and gases, with health monitoring for workers carrying out high-risk silica work and records retained.
- 10Administrative: a documented underground emergency response and rescue capability — refuge, self-rescuers where required, communication and rescue arrangements — briefed to all workers.
- 11Administrative: all workers must hold a valid White Card (General Construction Induction Training, CPCCWHS1001) before entering any construction workplace, with underground, confined space and tunnelling competencies verified as applicable.
- 12Administrative: conduct a pre-shift toolbox talk covering the day's work, ground and atmospheric conditions, the controls, plant movements, required PPE and emergency and rescue procedures, and record attendance in the consultation section.
- 13Administrative: consult workers and health and safety representatives on the work and its risks, record the consultation, and keep this document available at the workplace.
- 14PPE: underground high-visibility clothing, head protection, eye protection to AS/NZS 1337.1, hearing protection matched to the measured noise, gloves, and Class I or Class II safety footwear with protective toecap to AS/NZS 2210.3.
- 15Administrative: review and update this SWMS whenever the work, the ground or atmospheric conditions, the plant or the controls change, after any incident or near miss, when a worker or health and safety representative raises a concern, or at minimum every 12 months.
Applicable Codes of Practice
The national model code for tunnelling work, covering ground control, atmosphere, ventilation, emergency and the management of underground hazards.
Excavation, shaft and ground-support controls for the excavated openings and access shafts of the tunnelling work.
Atmospheric testing, ventilation, entry permit and rescue controls for the confined underground workings, shafts and chambers.
The risk assessment, silica risk control plan, air monitoring and health monitoring duties where the work generates respirable crystalline silica.
Selection, fit testing and use of P2, powered and supplied-air respiratory protection for the silica, dust, diesel particulate and atmospheric hazards of the underground work.
High-Risk Construction Work triggered
Excavating a tunnel by drill and blast is work involving a tunnel, which is high risk construction work requiring a SWMS before the work commences.
The underground heading, which may be oxygen-affected or have a contaminated or flammable atmosphere, brings the work within the confined space category and its controls.
Blasting the face uses explosives, which is high risk construction work on that count and is additionally regulated under the explosives legislation.
This is tunnelling work, which engages the high risk construction work categories above under the model WHS Regulations, so a SWMS must be prepared before the work commences, kept readily accessible, reviewed as necessary, and given to the principal contractor if one is appointed. Tunnelling is carried out to the model Tunnelling work Code of Practice and a rigorous regime of ground control, ventilation and emergency preparedness, and the confined space, excavation and, where relevant, explosives controls apply. Where the work generates respirable crystalline silica, the silica risk control plan, air monitoring and health monitoring duties apply, with the exposure standard reframed as a workplace exposure limit from 1 December 2026. An incident in a tunnel can trap and kill workers with limited means of escape, and breaches of the primary duty of care under the model WHS Act are actively enforced, with offence categories running from failure-to-comply through to reckless conduct, and the most serious breaches carrying imprisonment for individuals. Body-corporate maxima are substantial and indexed; the current maximum follows the prevailing schedule of the responsible regulator.
Who this is for
- →Drill and blast tunnelling crews excavating tunnels and underground headings.
- →Licensed shotfirers and charge-up crews working at the tunnel face.
- →Underground ground-support and mucking crews.
- →Tunnelling and geotechnical engineers and blast designers.
- →Project managers and supervisors overseeing the tunnel SWMS, the explosives controls and rescue arrangements.
What you receive
- ✓Editable Microsoft Word document (.docx) fully compatible with Microsoft Word 2016 and newer, Google Docs, and LibreOffice Writer.
- ✓Title page with editable fields for PCBU name, ABN, site address, project name, principal contractor details, and document revision date.
- ✓Hazard register with the drill and blast tunnel hazards — each with a documented consequence, inherent risk rating on a 5x5 likelihood-consequence matrix, hierarchy-of-control measures, and residual risk rating.
- ✓Drill, charge, blast and re-entry cycle prompts, a misfire-management procedure, ground-support and ventilation control fields, and a silica risk control plan aligned to the model crystalline silica Code of Practice.
- ✓Confined space entry, atmospheric-monitoring and underground emergency and rescue prompts, and a silica risk control plan aligned to the model crystalline silica Code of Practice referencing the 0.05 mg/m3 exposure standard.
- ✓Competency, ticket and induction verification fields, and a respiratory protection selection and fit-test record per AS/NZS 1715.
- ✓Worker consultation record per the model WHS Act consultation duty and a worker sign-on register (blank, expandable).
- ✓Applicable legislation and Codes of Practice schedule pre-populated for the model WHS jurisdiction with a state-variance reference table covering the harmonised states, plus Victoria.
- ✓Emergency procedure template and a revision log.
Worked example
A tunnelling crew is advancing a tunnel through rock by drill and blast, drilling a face pattern, charging it with explosives, blasting, mucking out and supporting the ground each cycle. Because the work involves a tunnel, a confined and potentially contaminated atmosphere, and explosives, a SWMS is prepared, and the explosives work complies with the explosives legislation. Before each round, the face and muckpile are checked for misfired or live charges from the previous blast. Ground support is installed to a competent person's design in a controlled sequence so workers are not under unsupported ground, with ground behaviour monitored. Drilling is wet to control respirable silica, and forced ventilation dilutes and removes silica, diesel particulate and gases with continuous atmospheric monitoring. The blast is designed for the confined heading by a competent person, a licensed shotfirer carries out the charging, tie-up and firing under a defined cycle, and exclusion is enforced before firing. A misfire-management procedure governs any misfire. Post-blast re-entry occurs only after ventilation has cleared the toxic fumes and the atmosphere is confirmed safe. Air monitoring tracks silica and diesel particulate, with health monitoring for silica-exposed workers, and an emergency and rescue capability is in place. The SWMS, blasting and monitoring records are retained.
Related legislation
- Model Work Health and Safety Act — primary duty of care; the duty to consult workers; the reckless-conduct offence; and notifiable-incident provisions, as enacted in each jurisdiction.
- Model Work Health and Safety Regulations — Section 291 high risk construction work and the SWMS preparation and review duties, the confined space provisions, and where relevant the crystalline silica high-risk processing, silica risk control plan, air monitoring and health monitoring provisions, as enacted in each jurisdiction.
- Model Codes of Practice — Tunnelling work; Excavation work; Confined spaces; and Managing risks of respirable crystalline silica in the workplace (2025).
- Where blasting is used, the explosives legislation governs the licensing and authorisation of shotfirers and the storage, transport and security of explosives; and the diesel particulate matter exposure standard, currently 0.1 mg/m3 (sub-micron elemental carbon) with a Workplace Exposure Limit of 0.01 mg/m3 (respirable elemental carbon) from 1 December 2026, applies underground.
- Victoria operates under the Occupational Health and Safety Act 2004 and the Occupational Health and Safety Regulations 2017, with the high risk construction work, tunnelling and confined space provisions applying in place of the model instruments.
Frequently asked questions
Why is drill and blast tunnelling so hazardous?
It combines the severe hazards of underground tunnelling — ground instability, a confined and potentially contaminated atmosphere, restricted egress, respirable crystalline silica and diesel particulate — with the hazards of explosives: premature initiation, flyrock and air overpressure in the confined heading, misfires leaving live charges, and toxic post-blast fumes. It engages several high risk construction work categories and the explosives legislation, so a SWMS and licensed blasting controls are required.
What is a misfire in tunnel blasting?
A misfire is a charge that fails to detonate as planned and remains live in the face or muckpile, where it can detonate during mucking or the next drill cycle, including if drilled into. It is managed by a misfire-management procedure covering identification, marking, exclusion and the defined method of dealing with the misfire, and by checking for misfired or live charges before drilling the next round.
When can workers re-enter the heading after a blast?
Only after the ventilation has cleared the toxic post-blast fumes — including oxides of nitrogen and carbon monoxide — and the atmosphere is confirmed safe. The confined heading concentrates the fumes, so re-entering before the ventilation has cleared them risks poisoning, and the heading is ventilated and the atmosphere checked before re-entry.
Is drill and blast tunnelling high-risk silica work?
Where the rock is silica-bearing, drilling and processing it is high-risk processing of a crystalline silica substance, so a silica risk control plan is prepared, wet drilling and water suppression supported by ventilation control the silica, and air monitoring against the 0.05 mg/m3 standard with health monitoring for exposed workers applies, in addition to the tunnel, confined space and explosives controls.
What categories and licensing apply?
Drill and blast tunnelling engages the tunnel, confined space, contaminated-or-flammable-atmosphere and explosives high risk construction work categories, so a SWMS is required before the work begins. The explosives are additionally regulated under the explosives legislation governing the licensing of shotfirers and the storage, transport and security of explosives.