An isolation checklist mining crews can rely on proves, step by step, that every source of hazardous energy on a piece of plant has been identified, isolated at the correct point, locked, tagged, released or contained, and tested dead before anyone puts their hands or body into it. It then covers the reverse: handover, removal of locks and a controlled return to service, so nothing rests on an assumption that the plant is safe.
This guide covers what Queensland and New South Wales law requires, where isolations go wrong, and a field checklist by stage with an escalation trigger for each check. It is generic: your site’s isolation procedure wins wherever the two differ. It is one of the field checks in our mine site inspection checklist guide.
Why isolation verification matters
Lockout tagout in mining rarely fails because someone skipped the lock. It fails through a lock on the wrong isolator, an energy source nobody identified, or stored energy never released: the paperwork said isolated, and the plant was not.
The Queensland inspectorate’s safety alert 344 on a worker injured by ineffective isolation is a textbook case. A crew locked out the valves either side of a pump station control valve and bled pressure, but missed a non-return valve in between. The section holding the control valve stayed at 9 MPa, nobody checked the gauges that showed it, and an ejected component struck a worker’s hand. The alert’s recommendation is the core of every checklist below: after isolating, locking and tagging, always test for dead.
Where a site treats isolation as a critical control, it belongs in critical control verification in the field, not just a permit signature.
What the law requires
Queensland coal
Section 78 of the Coal Mining Safety and Health Regulation 2017 requires a coal mine to have a standard operating procedure for controlling the risk of an unplanned release of energy from plant, including positively isolating the energy source. Where an electrical or mechanical source is positively isolated, the procedure must cover testing for zero potential. It must also cover taking plant out of service and returning it to service.
Two details shape any checklist. Where a person’s safety is directly affected by the plant’s operation, the procedure must let that person personally control its return to operation by attaching a danger tag or lock. And positive isolation must be manually initiated: for electrical equipment it must isolate all active power conductors and prevent unintended re-energisation, for other plant restoring energy must need a manual action, and the isolation device must be clearly marked as the positive means of isolating that plant.
Queensland metalliferous mines and quarries
Section 107 of the Mining and Quarrying Safety and Health Regulation 2017 requires the safety and health management system to provide for isolating plant, taking plant out of service, testing plant or its energy source for zero potential, and returning plant to service, and to provide for locking out and tagging where a person’s safety is directly affected. Where the risk makes it necessary, section 103 requires plant to have an isolation facility that can be locked out and tagged or otherwise secured, and section 27 requires a full current isolation facility for electrical equipment, clearly labelled and compatible with the mine’s lock-out procedures.
The inspectorate’s guidance is QGN 02 Isolation of plant, issued in February 2019 by the Mineral Mines and Quarries Inspectorate. It is a guidance note, not a guideline or a recognised standard, and it says so itself: in some circumstances following it may not be enough to comply with the legislation. It was written under the Mining and Quarrying Safety and Health Act 1999, not for coal mines, but its practical steps translate directly to a dragline, a wash plant or a coal handling conveyor.
New South Wales
Under the Work Health and Safety (Mines and Petroleum Sites) Regulation 2022, energy isolation on a mine site sits inside the principal control plans. Under Schedule 2, the mechanical engineering control plan must set out control measures for the unintended operation of plant and the unintended release of mechanical energy, and those measures must take into account safe work systems for the isolation, dissipation and control of all mechanical energy sources. The electrical engineering control plan must do the same for all electrical energy sources.
Identifying every energy source
QGN 02 lists the energies beyond electrical: mechanical (drives and rotating machinery), pressure (compressed air, vacuum, hydraulics), gravity (counterweights, truck trays, hung-up material, vehicle runaway), stored energy in springs and wire ropes, thermal, radiation and chemical. On mobile plant add batteries, accumulators, suspension struts and the tyres themselves.
Stored energy is rarely visible, so QGN 02 asks for risk based processes, run by people who know the plant, to find it. The test on the day: can anything move, spin, fall, spray, discharge or heat up with every isolator locked? If the answer is “not sure”, the isolation is not finished.
Just as important is what does not count as isolation. QGN 02 says emergency stops, conveyor pull wires, switches in control circuits (including software controls) and ignition keys are not to be used for isolation. An out of service tag is not isolation either. It protects the plant from being started, never the person working on it.
Testing for dead
The test has to suit the energy. QGN 02 gives examples: attempting to start the plant under controlled conditions, confirming that valves used to release energy are not blocked, phase indicator lamps and pressure gauges. The RSHQ alert above adds a test instrument for electricity, working hydraulic levers while watching gauges, and opening drains on both sides of a valve for air and water.
QGN 02 also says test and indicator equipment must be checked for accuracy as part of the isolation. Release devices should stay released while work goes on: a bleed valve left open shows the energy has gone and stops a slow build-up past a leaking seal.
Personal locks, group isolation and handover
QGN 02 describes four methods, chosen by risk assessment: single point with one worker, single point with several workers using a scissor lock, several isolation points with a limited number of workers on fixed plant, and group isolation using a lock box. In a group isolation the person in charge locks every isolation point with dedicated locks, puts the keys in the lock box and locks it, then every worker adds their personal lock to the box. Only when every personal lock is off does the person in charge inspect the plant and remove the isolation locks.
Personal locks should have one unique key that stays with the worker, tags should show at least the worker’s name and the date, and personal locks come off at the end of the task or shift, with an out of service tag fitted if work is unfinished.
Shift change is a weak point in a long isolation: the incoming crew inherits an isolation they did not do and should re-verify it. On mobile plant, isolation links directly to the pre-start inspection the next operator performs.
Isolation checklist for mining and quarry plant
QGN 02 describes three key stages to any isolation: isolation, validation that it is effective, and re-energisation. The checklist below follows that shape. Add your site’s test methods, and treat anything in the right hand column as stop work.
| Check | What good looks like | Escalate if |
|---|---|---|
| 1. Plan and identify | ||
| Task and plant identified | Correct plant confirmed by asset number and location | Parallel or identical plant nearby and the correct unit is not confirmed |
| Isolation procedure or point list available | Current isolation procedure, diagram or point list for this plant is at the job | No procedure, or it does not match the plant as installed |
| All energy sources listed | Electrical, mechanical, pressure, gravity, stored, thermal, radiation and chemical each considered | Any energy type marked “not sure” |
| Upstream and downstream sources | Sources before and after the plant identified, including feed conveyors, bins and connected lines | Connected plant can feed energy or material into the work area |
| Hidden and stored energy | Accumulators, springs, counterweights, non-return valves, capacitors and batteries identified | A component in the system is unknown or undocumented |
| Isolation method chosen | Single point, scissor lock, multi-point or group isolation selected per procedure | Method does not suit the number of workers or points |
| People competent | Everyone locking on is trained and assessed for this plant’s isolation | Untrained worker without direct supervision by a competent person |
| 2. Isolate, lock and tag | ||
| Correct isolation points | Each isolator’s label matches the plant and the point list | Labelling missing, ambiguous or inconsistent between locations |
| Not a control device | No emergency stop, pull wire, control switch, software control or ignition key used as the isolation | Any control device relied on as the isolation |
| Isolation devices operated | Full current isolators open, valves closed, energy supply physically separated | Isolator cannot be fully operated or its position cannot be seen |
| Locks fitted | Isolation locks on every point, device cannot be moved while locked | A point that cannot be locked, or a lock that does not secure the device |
| Tags fitted | Tags legible with name and date at minimum | Unsigned, illegible or undated tags |
| 3. Release stored energy | ||
| Pressure released | Hydraulic and air pressure bled to zero on both sides of every valve, gauges read zero | Gauge reads above zero, or a section of line cannot be bled |
| Gravity controlled | Attachments lowered to the ground, trays down or propped, chocks and pins fitted | Suspended load or raised component with no mechanical support |
| Mechanical energy released | Springs, belts and counterweights at rest or restrained, drives cannot rotate | Belt tension or counterweight still acting on the work area |
| Electrical stored energy | Capacitors discharged, batteries isolated, high voltage conductors earthed where required | No means to discharge or confirm discharge |
| Release devices left in place | Bleed and drain valves left open while work continues | Release valve closed again before work is complete |
| 4. Test for dead | ||
| Test equipment checked | Test instrument or gauge proved on a known source before and after use | Test equipment not checked or out of date |
| Start attempt | Start attempted under controlled conditions and the plant does not respond | Any movement, sound or indication of energy |
| Electrical zero potential | Tested with an appropriate instrument at the work point | Any voltage detected |
| Re-accumulation monitored | Plan in place to recheck energy that could build up during the task | Pressure, heat or charge rising during work |
| 5. Personal and group locks | ||
| Every worker locked on | Each person exposed has their own lock on the point, scissor lock or lock box | Anyone working under another person’s lock |
| Lock box secured | Isolation keys inside, box locked by the person in charge | Key outside the box or box not locked |
| Personal key control | One unique key per personal lock, held by its owner | Duplicate or master keys in circulation |
| Out of service tags used correctly | OOS tag used only to protect plant, with the reason written on it | OOS tag used in place of a personal lock |
| 6. Handover and shift change | ||
| Isolation status communicated | Incoming person in charge briefed on points, locks, tests and stored energy | No face to face or recorded handover |
| Re-verification | Incoming crew re-tests for dead before starting work | Incoming crew relying on the previous test |
| Unfinished work | Personal locks removed at end of shift, OOS tag fitted where work remains | Personal locks left on overnight with nobody accountable |
| 7. De-isolation and return to service | ||
| Work complete | Guards refitted, tools and materials removed, plant fit to run | Guard missing or defect outstanding |
| Everyone clear | All personnel physically confirmed clear of the plant | Anyone unaccounted for |
| Locks removed in order | Personal locks removed by their owners first, then isolation locks by the person in charge | A lock removed by anyone other than its owner outside the defined process |
| Handback | Person in control of the plant told it is fit for use, or OOS tag fitted | Plant energised without handback |
Where isolation verification goes wrong
- Wrong plant, right procedure. QGN 02 records isolation of the wrong item of fixed plant where plant was installed in parallel.
- The isolation point list is out of date. A modification added a valve or a second supply and nobody updated the list.
- Verification is a tick. “Isolation verified: yes” with no record of how, by whom, or with what instrument tells a supervisor nothing.
- Nobody checks the system. QGN 02 expects isolation effectiveness to be monitored at regular intervals through supervisor checks, job observation and audit, with action when non-conformances are found. On many sites that monitoring is the part that quietly stops.
For quarry specific detail on fixed plant, crushers and conveyors, see our guide to isolation and lockout on quarry plant.
Making isolation checks visible to supervisors
The problem with most isolation paperwork is not the form. It lives in a book at the job, gets filed at shift end, and nobody above the crew sees whether the test for dead was done until something goes wrong.
HazView lets a site build its own isolation verification checklist, converted like for like from the existing form first. Conditional logic means a failed check, such as a gauge not reading zero, opens a follow-up section for what was done about it rather than a blank comment box. Crews attach photos of locks, lock boxes and gauge readings to the relevant question, and can complete it offline in a plant room or pit, syncing when back in range. The checklist can be pinned to the plant’s location on the site map, completed with no map at all, or attached to a specific hazard.
The completer signs off, a countersignature can be nominated by role, and a PDF record can be generated on submit and emailed to the supervisor. The supervisor checks and audits QGN 02 describes can then work from the same day’s records, and the site’s forms stay private inside its own deployment. See how HazView supports mine and quarry managers, or book a demo to see a checklist built from your own isolation form.
Related guides
- Mine Site Inspections in Australia: What the Law Requires, What to Check and What a Defensible Record Looks Like
- Quarry Inspection App: What a Quarry Actually Needs
- Critical Control Verification Checklists That Prove the Control Works
- Digital TARPs: From Laminated Card to Live Trigger
- All Inspections & Checklists guides
Frequently asked questions
Is QGN 02 mandatory?
No. QGN 02 is a guidance note, and it states that it is neither a guideline under the Mining and Quarrying Safety and Health Act 1999 nor a recognised standard under the Coal Mining Safety and Health Act 1999. The mandatory requirements sit in the regulations, such as section 107 of the Mining and Quarrying Safety and Health Regulation 2017 and section 78 of the Coal Mining Safety and Health Regulation 2017.
What is the difference between a personal danger tag and an out of service tag?
A personal lock and danger tag protects the person working on the plant and should be removed only by that person. An out of service tag warns that plant must not be started, usually because it is faulty or work is unfinished. It must never be used to protect someone working on the plant.
Who can remove a personal lock?
Only the worker who fitted it, in the normal course. QGN 02 expects an appropriate system for removing a lock and tag the worker left behind. In practice that system confirms the worker is off the plant and accounted for before anyone else removes the lock.
Does this checklist apply to coal mines as well as quarries?
Yes. QGN 02 was written for metalliferous mines and quarries, but the stages it describes match the coal requirements in section 78 of the Coal Mining Safety and Health Regulation 2017 and the NSW engineering control plan requirements.