Lockout in Canada: The Off Button Is Not an Energy-Isolating Device (2026)

Push buttons, selector switches and other circuit control switches are not energy-isolating devices. CCOHS states it plainly, and it is the single most common lockout failure on Canadian sites: someone presses stop, the machine goes quiet, and everyone treats that as isolation.

An energy-isolating device is a manually operated disconnect switch, a circuit breaker, a line valve or a block. Something that physically interrupts the energy path and can accept a lock. The off button interrupts a signal.

What CSA Z460 actually covers

The Canadian standard is CSA Z460, Control of Hazardous Energy: Lockout and Other Methods, currently in its third edition as Z460:20, superseding the 2013 and 2005 editions. Most guidance online cites the American regulation instead.

Its definition of hazardous energy release is broader than people expect: any motion, energization, start-up, or release of stored energy that, from the perspective of the person at risk, is either unintended or deliberate. Someone else starting the machine on purpose is inside the definition.

Lockout is recognized as the primary method of hazardous energy control. Where a task is integral to the production process, or full lockout would prevent completing it, other methods may be used, but those are based on a risk assessment rather than on convenience.

The task list is where most people find themselves unexpectedly in scope. The standard applies to erecting, installing, constructing, repairing, adjusting, inspecting, unjamming, setting up, troubleshooting, testing, cleaning, dismantling, servicing and maintaining machines, equipment or processes.

Unjamming is on that list for a reason. Clearing a jam is the classic task nobody locks out for, because it will only take a second and the machine is already stopped. It is also the task that removes fingers.

Stored energy is the part that gets skipped

Disconnecting the power supply is the beginning of isolation, not the end of it. A machine can be fully de-energized at the source and still hold enough energy to kill someone.

The sources worth working through every time: springs under compression or tension, hydraulic and pneumatic pressure in lines and accumulators, suspended or elevated parts held by gravity, rotating flywheels and other inertia, capacitors holding charge, thermal energy in hot surfaces and fluids, and chemical or process energy in lines and vessels.

CCOHS lists the required steps in order: shutting down, isolating, blocking, securing, and relieving stored or residual energy. Blocking and relieving are separate steps from isolating, which is exactly the distinction that gets collapsed in practice.

Then verify. Attempt to start the equipment from the normal controls, confirm nothing moves, and return the controls to off. For electrical work, test before you touch. A procedure that ends at applying the lock has skipped the step that catches the mistakes.

Note also that the scope of the standard now includes mobile mechanical equipment, which catches a lot of crews who think of lockout as something that applies to fixed plant.

One worker, one lock, one key

This is the rule that carries the whole system, and it is the one that erodes fastest on a busy site.

Each authorized worker applies their own individually keyed padlock to the energy-isolating device, and keeps that key in their own possession for the entire time they are exposed. The lock is not a label on the equipment, it is a physical guarantee that nobody can re-energize while you are inside the machine.

Workers shall not work under another worker's padlock. If two people are exposed, two locks go on. If ten are, ten locks go on, which is what hasps are for, and group lockout has its own documented procedure.

Tags accompany locks used for personal protection rather than replacing them. A tag says who and why; a lock is what actually stops the handle moving.

The removal rule follows from the same logic: your lock comes off by you, when you are clear. Procedures for removing a lock in the absence of the worker who applied it exist, and they are deliberately awkward, because the awkwardness is the safeguard.

What we do not sell

We do not stock padlocks, hasps, lockout tags, valve covers, breaker lockouts or lockout station kits. Those come from industrial safety suppliers, and they are the actual equipment this article is about.

What we supply is what the maintenance worker wears while doing the job the lockout makes safe. Eye protection for the moment a line is cracked or a component comes apart, covered in our safety glasses guide.

Hand protection for sharp edges, hot surfaces and the residual fluids that come out when a line is opened, covered in our guides to work gloves and choosing chemical resistant gloves, since draining a system is a chemical exposure as much as a mechanical one.

And footwear appropriate to the plant, covered in our guides to work boots for millwrights and work boots for industrial maintenance workers.

The program and the procedure are two documents

An organization has one overall lockout program. Each unique machine, piece of equipment or process then has its own detailed procedure or work instruction describing how to control its hazardous energy.

That machine-specific procedure identifies the equipment involved, the hazardous energy present, the type of energy-isolating or de-energizing devices required, where the lockout devices go and how they are installed, the steps for shutting down and isolating and blocking and securing and relieving residual energy, and the steps for placing and removing every lockout device.

A generic program with no machine-specific procedures is the most common gap in an audit, because it reads like compliance and provides no instruction to the person standing in front of the machine at 6am.

Roles need defining too. The standard distinguishes authorized workers, who apply locks and perform the work, from affected persons, who are not directly involved but whose work is impacted. Affected persons need to know the lockout is happening even though they are not applying anything.

Audit the written procedures and the actual practice against each other periodically, because procedures drift. Z460:20 also references the Canadian hazard identification and risk assessment standard, so a lockout program sits inside a wider assessment rather than standing alone.

Where lockout meets the other standards

Z460 does not work in isolation. It is designed to operate alongside CSA Z432 on safeguarding of machinery, CSA Z462 on workplace electrical safety, CSA Z463 on maintenance of electrical systems, and the Canadian Electrical Code.

The electrical overlap matters most in practice. Establishing an electrically safe work condition is a Z462 process that includes lockout as a component, and arc flash risk persists during the isolation and verification steps themselves. Our guide to arc rated and FR clothing under CSA Z462 covers what the worker wears while doing it.

Machine guarding sits above lockout in the hierarchy. A guard that lets the operator clear a jam without reaching into the danger zone removes the task that needed lockout in the first place.

Confined space work frequently requires lockout as a prerequisite, since isolating agitators, augers and inflow lines is part of making entry survivable rather than a separate exercise.

Where a task involves working at height on equipment, the fall protection and rescue planning apply on top, covered in our guide to suspension trauma and fall rescue.

Where programs fail

The stop button standing in for isolation is first, and it is worth checking on your own site this week rather than assuming.

Second is the quick job. Unjamming, clearing, adjusting and a brief look are the tasks where people reach in without isolating, and they are explicitly inside the standard's scope. The reasoning is always the same: it will take ten seconds, the machine is already stopped, locking out takes longer than the fix.

Third is stored energy. A crew that reliably locks the disconnect but never blocks the raised platform or bleeds the accumulator has a program that handles one energy source out of several.

Fourth is shift handover. A job that spans a shift change is where locks come off because someone needs the equipment and the person with the key has gone home. That situation needs a documented procedure decided in advance, not a bolt cutter.

Fifth is contractors. Visiting crews arrive with their own program, their own locks and their own assumptions, and the host site is responsible for making sure the two systems interlock rather than conflict.

For the wider picture see the complete PPE checklist for Canadian workers, our guide to PPE requirements for Canadian construction sites, our guide to CSA certified versus CSA compliant and our guide to CSA Z1220 first aid kit requirements.

Frequently Asked Questions

Is turning a machine off the same as locking it out?

No. CCOHS states that push buttons, selector switches and other circuit control switches are not energy-isolating devices. An energy-isolating device is a manually operated disconnect switch, circuit breaker, line valve or block: something that physically interrupts the energy path and can accept a lock.

What is the Canadian lockout standard?

CSA Z460, Control of Hazardous Energy: Lockout and Other Methods, currently in its third edition as Z460:20. It supersedes the 2013 and 2005 editions and works alongside CSA Z432 on machine safeguarding, CSA Z462 on workplace electrical safety and the Canadian Electrical Code.

Does lockout apply to clearing a jam?

Yes. Unjamming is explicitly within the standard's scope, alongside inspecting, adjusting, cleaning, troubleshooting, setting up and servicing. Quick tasks on apparently stopped machines are where a disproportionate share of serious injuries occur.

Can I work under someone else's lock?

No. Each authorized worker applies their own individually keyed padlock and keeps the key in their own possession while exposed. Where several workers are involved, each applies a lock, which is what hasps and group lockout procedures exist for.

What counts as stored energy?

Springs under tension or compression, hydraulic and pneumatic pressure including accumulators, elevated or suspended parts held by gravity, rotating inertia, capacitors, thermal energy in hot surfaces and fluids, and chemical or process energy in lines and vessels. Isolating the supply does not release any of it.

Is a tag enough on its own?

Generally no. Lockout is recognized as the primary method of hazardous energy control, and tags used for personal protection accompany locks rather than replacing them. A tag communicates; a lock physically prevents the device being operated.

This guide is general workplace safety information and is not training. Control of hazardous energy requires machine-specific written procedures, competent training and jurisdiction-specific compliance. Requirements differ across Canadian provinces and territories; confirm yours with the occupational health and safety authority that governs your workplace, and refer to CSA Z460 or the most current edition.