"Lockout Tagout (LOTO): Procedure Development Guide for Manufacturing"

I want to tell you about the most violent way an employee can die at work.

It doesn't involve a fall. It doesn't involve a chemical exposure. It doesn't even involve a fire.

It involves a machine that someone thought was off.

Every year in the United States, failure to properly control hazardous energy accounts for nearly 10% of serious workplace injuries in manufacturing. Workers are crushed by presses that cycle unexpectedly. Arms are torn off by conveyors that start without warning. Electricians are electrocuted by circuits they believed were de-energized.

In virtually every case, the investigation reveals the same root cause: the employer either had no lockout/tagout procedures, or had procedures that existed on paper but were never followed, never trained, and never enforced.

OSHA's Control of Hazardous Energy standard — 29 CFR 1910.147 — is the regulation designed to prevent these deaths. It's also one of the most frequently cited standards in manufacturing, appearing on OSHA's Top 10 list year after year.

Not because it's complicated. Because employers don't do it.

Scope: What the Standard Covers

1910.147 applies to the servicing and maintenance of machines and equipment where the unexpected energization or startup, or the release of stored energy, could cause injury to employees.

Key words: servicing and maintenance. This is not about normal production operations (though the machine guarding standard covers that). LOTO kicks in when someone is performing work on a machine that takes them beyond normal operations — clearing jams, adjusting components, cleaning internal parts, replacing worn elements, lubricating mechanisms, performing inspections that require access to danger zones.

The standard covers all types of energy — not just electrical. That's where employers get tripped up. They think LOTO is about flipping a breaker. It's about controlling every energy source that could injure someone.

The Seven Types of Hazardous Energy

Your LOTO procedures must account for every type of energy present in each machine. Miss one, and someone can die.

**Electrical:** The obvious one. Motors, circuits, control panels, batteries, capacitors. But don't forget stored electrical energy — capacitors can hold lethal charges long after power is disconnected.

**Mechanical:** Moving parts — gears, flywheels, springs, belts, chains, cams. A flywheel doesn't stop the instant you cut power. A compressed spring releases energy the moment its restraint is removed. Mechanical energy must be dissipated, blocked, or restrained.

**Hydraulic:** Pressurized fluid in cylinders, lines, and accumulators. Hydraulic systems can maintain thousands of PSI even after the pump is shut off. Accumulators store energy specifically to maintain pressure. You must bleed, block, or cap hydraulic energy sources.

**Pneumatic:** Compressed air in lines, cylinders, and receivers. Like hydraulics, pneumatic systems retain pressure after the compressor stops. Bleed the lines. Block the valves. Verify zero pressure.

**Thermal:** Heat or cold energy in systems — steam lines, furnaces, cryogenic equipment, molten materials. Thermal energy can't always be "locked out" in the traditional sense, but it must be controlled. Blocking valves, draining lines, allowing cool-down periods.

**Chemical:** Reactive chemicals in process equipment. Valves must be closed and locked. Lines must be bled, purged, or blanked. Residual chemicals in vessels can react, combust, or release toxic gases.

**Gravity:** The energy of position. A raised press ram. A suspended load. An elevated platform. If gravity can move it, and it can injure someone, it must be blocked, pinned, or otherwise prevented from descending.

Every machine in your facility has a unique combination of these energy sources. Your procedures must identify each one specifically.

Machine-Specific Written Procedures

Here's where the standard gets granular, and where most employers fail.

You must develop written, machine-specific LOTO procedures for each piece of equipment where employees perform servicing or maintenance. A generic "turn it off and lock it out" policy is not a procedure. It's a platitude.

Each machine-specific procedure must include six steps:

Step 1: Preparation

Before beginning LOTO, the authorized employee must understand:
- What type of machine or equipment is involved
- What hazardous energy sources are present
- What method will be used to control each energy source
- What magnitude of energy is stored or residual

This is the thinking step. The employee reviews the procedure, identifies the energy sources, gathers the necessary lockout/tagout devices, and mentally walks through the process.

Step 2: Shutdown

Notify all affected employees that the machine will be shut down. Then shut it down using normal stopping procedures — the stop button, the control switch, the standard operating procedure. Do not just yank the plug or trip the breaker as your first action.

An orderly shutdown prevents the additional hazards that come from emergency stops — hydraulic pressure spikes, mechanical shock, uncontrolled release of materials in process.

Step 3: Isolation

Physically isolate all energy sources. Open the electrical disconnect. Close and lock the steam valve. Block the hydraulic line. Disconnect the pneumatic supply. Pin the raised die.

Isolation means the energy source can no longer reach the machine. It's not enough to turn it off at the control panel — the energy must be isolated at the source.

Step 4: Apply LOTO Devices

Each authorized employee working on the machine applies their own lock and tag to each energy isolation device. Not a shared lock. Not a supervisor's lock. Their personal lock, with their name on it, keyed uniquely to them.

Tags must identify the employee, the date, and the reason for lockout. They must be standardized and durable enough to withstand the environment.

One employee, one lock, per energy isolation point. If five employees are working on the machine, there are five locks on every isolation device. No exceptions.

Step 5: Verify Stored Energy Dissipation

After lockout, you must address stored or residual energy. Bleed hydraulic and pneumatic pressure. Discharge capacitors. Block raised components. Allow thermal energy to dissipate. Verify that springs are released or restrained.

This step is the one that gets people killed when it's skipped. The breaker is locked out, but the hydraulic accumulator still holds 3,000 PSI. The motor is disconnected, but the flywheel is still spinning. Stored energy doesn't care about your lock. It cares about physics.

Step 6: Verification

The final and most critical step: attempt to start the machine. Push the start button. Cycle the control. Verify, through actual testing, that the energy isolation is effective and the machine cannot operate.

Then — and this is important — return the start controls to the off or neutral position. You don't want someone coming along later, seeing the start button in the "on" position, and assuming the machine is energized when it's actually locked out.

Verification is not optional. It's not "check the lock and you're good." It's active testing. Try to start it. Confirm it can't.

Authorized vs. Affected vs. Other Employees

The standard defines three categories of employees, and each has different responsibilities:

**Authorized employees** are the ones who actually apply and remove LOTO devices. They perform the servicing or maintenance work. They are trained in the recognition of hazardous energy sources, the type and magnitude of energy in the workplace, and the specific procedures for their assigned machines.

**Affected employees** are those whose jobs require them to operate or use a machine that is being serviced under LOTO, or who work in an area where servicing is being performed. They need to know what LOTO is, why the machine is locked out, and that they must not attempt to restart it.

**Other employees** are everyone else — people who might walk through the area. They need to know what a lockout device looks like and that they must never remove one or attempt to operate locked-out equipment.

An employee can be authorized for some machines and affected for others. The categorization is machine-specific, not person-specific.

Group Lockout Procedures

When multiple employees work on the same machine, you need group lockout procedures. The standard requires:

• One authorized employee is designated as the primary coordinator
• Each authorized employee applies their own personal lock to a group lockbox or to each isolation device
• The machine cannot be re-energized until every personal lock has been removed
• The primary coordinator ensures continuity of protection during the entire servicing operation

Group lockout is common in manufacturing during scheduled maintenance shutdowns. The key principle: no one removes anyone else's lock, ever. Your lock, your life.

Shift Change Protocols

What happens when the day shift mechanic has the machine locked out and the night shift mechanic takes over?

Your procedure must address this. The standard requires continuity of lockout protection during shift changes. The incoming employee applies their lock before the outgoing employee removes theirs. At no point is the machine unprotected.

This sounds simple. In practice, it requires coordination, communication, and a procedure that both shifts understand and follow. A machine that gets re-energized during a shift change because "the first guy took his lock off before the second guy put his on" is a machine that kills people.

Periodic Inspections: The Annual Reality Check

Here's a requirement that catches virtually every employer off guard.

You must conduct a periodic inspection of your LOTO procedures at least annually. The inspection must:

• Be performed by an **authorized employee OTHER than the one using the procedure being inspected**
• Cover each machine-specific procedure
• Verify that employees understand and follow the procedures
• Include a review between the inspector and each authorized and affected employee
• Be documented with the date, the machine/equipment inspected, the employees included, and the person conducting the inspection

This is not a paperwork exercise. OSHA expects an actual observation of the lockout procedure being performed, a conversation with the employees about the procedure, and documentation that the review occurred.

The "other than the one using the procedure" requirement is critical. You can't have a mechanic inspect his own procedure. Fresh eyes catch what familiarity misses.

Common Citation Triggers

If you want to know where employers get cited most often — and therefore where your program is most likely to be deficient — here's the list:

1. **No machine-specific written procedures.** The single most common citation. Having a generic LOTO policy is not the same as having procedures for each machine.
2. **No periodic inspections.** Either not done at all, or done improperly (self-inspections, no documentation, no employee review).
3. **Inadequate training.** Authorized employees who can't explain the LOTO procedure for their assigned machines. Affected employees who don't know what lockout is.
4. **Failure to identify all energy sources.** Electrical is locked out, but hydraulic, pneumatic, or gravity energy is ignored.
5. **No verification step.** Employees lock out and start working without verifying that the machine is actually de-energized.
6. **Shared or missing locks.** One lock for multiple employees. Locks without names. Keys kept in a common location.
7. **No stored energy dissipation.** Locks applied but accumulators not bled, capacitors not discharged, springs not released.
8. **No shift change protocol.** Gap in protection during shift transitions.

Every one of these is a Serious violation. Every one carries significant penalties. And every one of them has been associated with fatalities in the OSHA investigation files.

Building Your Program

Start with an energy survey of every machine in your facility. Identify every energy source — electrical, mechanical, hydraulic, pneumatic, thermal, chemical, gravitational. Photograph the isolation devices. Map the energy flow.

Then write machine-specific procedures. One procedure per machine (or per group of identical machines with identical energy sources). Use the six-step format. Include photographs or diagrams showing isolation device locations.

Train your authorized employees on the procedures for their specific machines. Train your affected employees on LOTO awareness. Document everything.

Buy enough locks and tags — personal locks for every authorized employee, with unique keys. Standardize your tags. Establish your group lockout and shift change protocols.

Schedule and conduct your annual periodic inspections. Document them thoroughly.

Then enforce the program. Not with memos. Not with break room posters. With consequences. The employee who shortcuts the procedure, who doesn't verify, who removes someone else's lock — that employee needs to be retrained, disciplined, or removed from authorized status.

Because the alternative to enforcement isn't a citation. It's a funeral.

And no employer wants to attend the funeral of someone who died because a procedure they wrote wasn't followed by someone they trained on a machine they owned.

Do the work. Follow the standard. Protect your people.