LOTO Procedure: Lockout Tagout on Mine Sites

What LOTO and isolation mean

Isolation is making sure plant cannot move or start while someone is working on it. SafeWork NSW describes an isolation procedure as a set of predetermined steps for tasks such as maintenance, repair, installation and cleaning of plant. The NSW Resources Regulator defines isolation as removing and disconnecting energy, stopping it being restored by accident, discharging residual energy, tagging or locking out, and testing that the energy has really been removed.

“Lockout tagout” or LOTO is the common name for the locking and tagging part. On site you will also hear isolation, lock-on, locking off and tag-on. Some are used loosely, so learn the terms your site uses. Our mining glossary covers common ones.

Typical LOTO steps

SafeWork NSW describes the lockout process as: shut down the machinery, identify all energy sources and hazards, identify all isolation points, isolate all energy sources, control stored energy, lock out the isolation points, tag, and test by trying to reactivate the plant. The NSW Resources Regulator notes that larger mines often use a 12-step isolation and restoration process, and smaller sites use shorter versions. Whatever the number of steps, it says one key message stays the same: verify the isolation, test for dead.

A general lockout tagout sequence

Shut the plant down by its normal controlsDo this before isolating, not after.
Identify all energy sources and other hazardsElectrical is only one. Include hydraulic, pneumatic, fluids under pressure, gravity, springs and heat.
Identify all the isolation pointsYour site's isolation plan, matrix or register may list them. Check it covers feeds into and away from the item.
Isolate each energy sourceSwitch off, close valves, disconnect, or chock and secure, as the procedure says.
Control or release stored energyBleed pressure, support raised parts, discharge capacitors. Stored energy is where many incidents happen.
Lock out every isolation pointUse your own personal lock. A lock is the control. A tag alone is not.
Tag each pointDanger tag with your name on it, plus isolation tags if your site uses them.
Test for dead: try to start the plant or test the systemThis proves the isolation worked and the stored energy is gone. Do it without exposing yourself or others.
Do the workKeep your lock on until you are finished. If the job changes, stop and check the isolation still covers it.
Finish and check the job, then remove locks and tagsEach person removes their own. Make sure everyone is clear before plant is returned to service.

This is a general sequence built from regulator descriptions. It is not your procedure. Your site may add steps, such as a second person verifying the isolation, a permit, or an isolation plan.

Stored energy and test for dead

Switching a machine off is not the same as removing all its energy. The NSW Resources Regulator splits energy into primary energy, which is isolated by switching or closing valves, and secondary or stored energy, which is isolated by securing, chocking, bleeding off, switching or earthing.

Energy sources to think about

Electrical, including batteries and capacitor banks
Hydraulic and pneumatic pressure, water and other fluids or gases under pressure
Springs, accumulators and tensioned parts
Gravity: raised booms, buckets, tray bodies and anything that can fall or roll
Material hang-up in chutes, hoppers and truck bodies
Heat, steam, fuels and radiation

Stored energy is where the Regulator found things going wrong. In a September 2024 bulletin on pressurised systems it reported 15 incidents over 18 months, and said that in almost all of them workers failed to release the stored energy from the system they were working on. It says procedures should include a step to test and confirm the system is de-energised, and it names double block and bleed (two separate isolation valves and one drain valve) as good practice for pressurised systems.

Locks and tags

The rule that matters most: a tag is not an isolation device. SafeWork NSW and the WA guideline both say a tag only gives information, and only a lock is effective at isolating an energy source. The WA guideline also says isolation locks should only be used to isolate energy sources, not for general purposes.

Tags you may see (names and colours vary by site)

Personal danger tagGoes with your personal lock. Shows you are working on the plant and could be injured if the isolation is not maintained. Only the person named on it removes it.
Isolation tagDescribes the plant isolated, the reason, the permit number if there is one, and who did the isolation.
Out of service tagSays plant is not fit for use. It does not protect a person working on it, and is never a substitute for a personal lock or danger tag.
Information tagPasses on the current status of plant. Never a personal isolation device and not a replacement for an out of service tag.
Commissioning or testing tagUsed when plant is being tested. Prefer verified isolation over live testing where possible.

The NSW Resources Regulator says most small mines it describes issue personnel red personal isolation locks with the person’s name and contact details on a label, and keep personal danger tags and spare locks for visitors and contractors who do not have their own. Do not assume the same colours on your site. The WA guideline recommends tag colours that are consistent with AS 1319, but check what your site uses.

Personal and group isolation

The WA guideline describes personal isolation as isolation by one person who also does the work and de-isolates, under their own control, completed before the end of their shift. Where those criteria cannot be met, it says a permit-to-work system should apply, and all group isolations should be done under a permit-to-work system.

When more than one person works on the same plant, each person attaches their own lock. SafeWork NSW says to use a device that takes more than one padlock, such as a hasp, or one padlock with the key locked in a box that each worker locks separately. The NSW Resources Regulator says a hasp typically takes up to six people. For more people or many isolation points, such as a plant shutdown, it describes group lockout stations or lock boxes: each isolation point gets its own isolation lock, the keys go in the box, and each person puts their personal lock on the box. The isolation locks can only be removed once everyone has taken their personal lock off.

The WA guideline adds that group isolations should be installed by at least two competent people, so the isolation can be checked.

Who can remove a lock

The person who put a lock and danger tag on removes them. SafeWork NSW says padlocks and tags may only be removed by the signatories to the tag, and that each worker should have their own lock, tag and key, with no duplicate key except a master key kept in a secure place for emergencies. The WA guideline says a personal lock and danger tag should be removed by the person before they leave site at the end of the shift, and that the procedure needs to say what happens if someone does not.

If the work is not finished at shift end and the plant must stay isolated, the WA guideline says arrangements are needed to secure out of service tags at each isolation point before personal locks and danger tags are removed, and the outgoing shift should give a hand-over briefing covering work status, known hazards, and removal and replacement of locks and tags. Removing someone else’s lock is only for exceptional cases, such as a medical emergency, and the WA guideline says it should be authorised by a management representative after a formal process shows the person is not at the work site. Never do this on your own.

Common failures

These come from NSW Resources Regulator bulletins. They are NSW findings, but the lessons apply anywhere.

What goes wrong

Assuming pressure has bled off because a drain line looks emptyNSW SB24-06 lists this as a contributing factor. Make sure drain lines are clear and test.
Skipping the test for deadListed in SB24-06 among the contributing factors.
Not following the site's isolation procedure or the manufacturer's procedureAlso listed in SB24-06.
Opening the wrong line: isolating pipeline number 1 and loosening the flange on number 2One incident in SB24-06. Confirm exactly what is isolated before you break anything.
Not applying line of fire controls when separating pipes, hoses and componentsSB24-06 recommends identifying them before disassembly.
Lock box locks missing or not matching the people on the permitSB18-19 found lock boxes in service with locks missing, and the number of people locked on not matching the names on the permit.
Not knowing what is isolatedSB18-19 found most individuals fitting a personal lock to a lock box did not know what was actually isolated.
Isolation permit filled out before the isolation steps were doneFound at one site by the NSW Resources Regulator (SB18-19).

Also remember that emergency stops, lanyards and pullwires are not isolation devices. The Regulator says they cannot be used to positively isolate plant.

LOTO and permits

On many sites the isolation is recorded on, or linked to, a permit. The NSW Resources Regulator notes that large maintenance isolations cover multiple workers, can run over multiple shifts, and are usually managed through permits. The WA guideline says an isolation permit should record the method and list of isolations, and that sub-permits (such as confined space entry or hot work) should be linked to the main permit. Read our guide to how permit to work systems operate to see where the isolation sits in the permit lifecycle, and how a JSA, a SWMS and a Take 5 can sit alongside it. Your site decides how those fit together.

Follow your site’s procedure

Everything above is general. Your site has its own isolation procedure, isolation plans or registers, tag and lock colours, permit forms, and a list of people authorised to do isolations. These override this page. Ask your supervisor or the site safety team if any step is unclear, and stop work if the isolation does not match the job.

Check these before your first isolation on a new site: who is authorised to isolate, where personal locks and tags are issued, where the isolation plans are, what the test for dead step involves, and what to do if you are not sure.

Sources: WorkSafe WA guideline, SafeWork NSW factsheet, NSW Resources Regulator presentation, SB18-19 and SB24-06.

Frequently asked questions

What is a LOTO procedure?

A LOTO (lockout tagout) procedure is a fixed set of steps for isolating a machine from every energy source, locking the isolation points, tagging them and proving the machine is dead before anyone works on it. SafeWork NSW describes an isolation procedure as a set of predetermined steps for tasks such as maintenance, repair, installation and cleaning of plant. On a mine site the exact steps come from your site's isolation procedure, so follow that one.

What are the steps of lockout tagout?

In general: shut the plant down, identify all energy sources and isolation points, isolate them, control stored energy, lock out each point, tag it, then try to start the plant to prove the isolation works. After the work, the locks and tags come off and the plant is checked before return to service. SafeWork NSW lists these steps, and the NSW Resources Regulator says larger mines often use a 12-step process. Your site's version may have more steps, in a different order.

What is the difference between a lock and a tag?

A lock physically stops the energy source being switched on. A tag only gives information. Both SafeWork NSW and the WA guideline say a tag is not an isolation device and should never be used alone to isolate an energy source. A personal danger tag goes with your personal lock and shows who is working on the plant.

Who can remove a lockout lock?

Normally only the person whose lock it is. SafeWork NSW says padlocks and tags may only be removed by the signatories to the tag. The WA guideline says a personal lock should not be openable by another person, and that removal in an exceptional case (such as a medical emergency) should only be authorised by a management representative after a formal process confirms the person is not at the work site. Never cut or remove another person's lock yourself.

What does test for dead mean?

Test for dead means proving the isolation worked before you start, by testing that the energy is really gone. For plant, SafeWork NSW describes trying to reactivate it without exposing anyone to risk. For pressurised systems, the NSW Resources Regulator says the procedure should include a step to test and confirm the system is de-energised, and it names a double block and bleed isolation as good practice.

Is an emergency stop button a valid isolation?

No. The NSW Resources Regulator says emergency stops, lanyards and pullwires are not primary isolation devices and cannot be used to positively isolate plant. They are emergency stop devices only.

Do I need a permit as well as locks?

Often, yes. The WA guideline says all group isolations should be performed under a permit-to-work system, and that a personal isolation applies only to a single competent person who isolates, works and de-isolates within their own shift. Whether your job needs a permit is set by your site's procedure.

Sources

Last updated 10 October 2026. Facts on this page come from the sources below.

The sources are regulator and government documents read on 10 October 2026. The WorkSafe WA guideline is a Department of Mines and Petroleum document dated 2015 that refers to the Mines Safety and Inspection Act 1994, so legislation references in it may be out of date. The SafeWork NSW factsheet is written for general workplaces under the NSW WHS Regulation. The NSW Resources Regulator documents are about NSW mines, and their presentation does not cover high voltage isolation. Rules, steps, colours and roles differ between jurisdictions, mines and employers. This page is not a procedure or training. Follow your own site’s isolation procedure and induction.

LOTO Procedure: Lockout Tagout and Isolation on Australian Mine Sites