Lockout/Tagout
Control Hazardous Energy, Save Lives
What is Lockout/Tagout?
Lockout/Tagout (LOTO) is a safety procedure that ensures hazardous energy is properly isolated and rendered inoperative before employees perform service or maintenance on equipment. It prevents accidental startup, energization, or release of stored energy that could cause injury.
- 3,000+ injuries occur annually from failure to control hazardous energy
- 120+ fatalities each year from improper LOTO
- 10% of serious workplace accidents involve failure to control energy
- Injuries include amputations, electrocutions, crushing, burns, and death
- All are preventable with proper LOTO procedures
Learning Objectives:
- Understand what hazardous energy is and why it must be controlled
- Recognize the types of energy sources requiring LOTO
- Identify the three employee classifications for LOTO
- Know the six steps of LOTO procedures
- Understand critical LOTO rules that protect everyone
What is Hazardous Energy?
Energy that can cause harm
Hazardous energy is any source of energy that, if not controlled, can cause injury or death. This includes both active energy sources and stored energy that can be released unexpectedly.
- Capacitors holding electrical charge after power is off
- Springs under tension
- Compressed air or hydraulic pressure trapped in lines
- Flywheels still spinning after power is cut
- Suspended loads that can fall
Three Types of Employees
Understanding roles and responsibilities
OSHA defines three categories of employees based on their relationship to LOTO procedures. Knowing which category you're in determines what you can and cannot do.
• Apply and remove their own locks/tags
• Perform service and maintenance on locked-out equipment
• Verify energy isolation
• Work inside LOTO boundaries
Requirements:
• Specific LOTO training
• Employer authorization
• Knowledge of energy sources and isolation methods
• Recognize when LOTO is in use
• Understand the purpose of LOTO
• Know not to restart locked-out equipment
Cannot do:
• Apply or remove locks/tags
• Service locked-out equipment
• Bypass or defeat LOTO devices
Requirements:
• Awareness training on LOTO purpose and procedures
• Recognize lockout/tagout devices
• Understand they should not touch locked-out equipment
Cannot do:
• Remove any locks or tags
• Operate locked-out equipment
• Enter LOTO work areas without authorization
Requirements:
• Basic awareness that LOTO exists and should never be interfered with
The Six Steps of LOTO
The proper energy control sequence
OSHA requires a specific sequence for controlling hazardous energy. This overview is for awareness—only authorized employees perform these steps.
Preparation
Survey the equipment to identify all energy sources. Review equipment manuals, diagrams, and procedures. Identify all energy isolation points (breakers, valves, switches). Gather necessary locks, tags, and tools. Notify all affected employees that lockout will occur.
Notification
Inform all affected employees before beginning LOTO. Notify operators, maintenance staff, and anyone working nearby. Explain what equipment will be locked out, why, how long it will take, and who to contact with questions. Post signs if needed.
Shutdown
Shut down equipment using normal operating procedures. Use proper shutdown sequence per manufacturer instructions. Allow equipment to come to complete stop. Never force equipment off in a way that could cause damage or create additional hazards. Verify shutdown is complete.
Isolation
Disconnect equipment from ALL energy sources. Open circuit breakers, close valves, disconnect power supplies. Isolate every identified energy source. Block or secure mechanical components. Relieve or block stored energy (springs, hydraulic pressure, elevated components). Verify isolation is complete.
Lockout/Tagout
Apply lockout or tagout devices to energy isolation points. Each authorized employee working on equipment applies their own lock and tag. Locks must prevent operation of isolation device. Tags identify who applied the lock and warn against re-energization. Use standardized locks and tags per company procedures.
Verification
Test to confirm equipment is de-energized and cannot restart. Check that all personnel are clear. Try to operate equipment using normal controls—it should NOT start. Test for presence of energy using appropriate instruments (voltmeter for electrical, pressure gauge for pneumatic/hydraulic). Verify stored energy is released. Only after verification is work safe to begin.
Lockout and Tagout Devices
Hardware that prevents re-energization
LOTO devices physically prevent energy isolation devices from being operated. Recognizing these devices helps you know when equipment is locked out.
Requirements:
• Must be durable and substantial
• Each worker uses their own unique lock
• Only the person who applied the lock can remove it
• Usually red with "DANGER - DO NOT OPERATE" marking
• Must withstand environment and force
Common types: Padlocks, hasps (for multiple locks), circuit breaker locks, valve lockouts, plug lockouts, cable lockouts
Requirements:
• Attached to every lock
• Must include "DANGER - DO NOT OPERATE" or similar
• Lists employee's name, date, and reason
• Made of durable material
• Cannot be removed without destroying
Important: Tags ALONE are not sufficient—they must accompany locks. Tags warn but don't physically prevent operation.
- Durable: Withstand the environment for the expected service period
- Standardized: Consistent in color (usually red), shape, or size across the facility
- Substantial: Cannot be easily removed without tools
- Identifiable: Used only for energy control, never for other purposes
- Legible: Tags must remain readable in all conditions
- Never remove someone else's lock or tag—even if you think they forgot it
- Never operate equipment that has locks or tags on it
- Never cut off locks or bypass LOTO devices
- Never use regular locks or non-LOTO locks for lockout
- Never remove your own lock until work is complete and equipment can safely restart
Critical LOTO Rules Everyone Must Follow
Non-negotiable safety requirements
These rules apply to everyone—authorized, affected, and other employees. Violating any of these can result in death or serious injury.
- Allow equipment to start while they're inside or working on it
- Cause electrocution, crushing, amputation, or death
- Result in criminal charges and termination
- Do NOT attempt to start or operate it
- Do NOT remove locks or tags to "test" if it works
- Do NOT bypass isolation devices
- Do NOT assume the lockout doesn't apply to you
- Share locks with coworkers
- Work under someone else's lock
- Apply locks for other people
- Use a "group lock" unless specifically trained on group lockout procedures
- Your work is completely finished
- All tools and materials are removed from equipment
- All personnel are clear of danger zones
- All guards and safety devices are reinstalled
- You've verified equipment can safely restart
How to Recognize LOTO in Progress
Signs that equipment is locked out
As an affected or other employee, you need to recognize when LOTO is in effect so you can stay away from equipment and avoid interfering with the lockout.
- Locks on electrical panels, breakers, or disconnects: Usually bright red padlocks with "DANGER - DO NOT OPERATE" tags attached. May be single locks or multiple locks on a hasp.
- Lockout devices on valves: Valve lockouts prevent the valve handle from being turned. Tags will be attached to the lockout device or valve handle.
- Lockout devices on plugs and cords: Special covers or locks prevent electrical plugs from being inserted into outlets or equipment from being plugged in.
- Warning tags on equipment controls: Even without locks, you may see "DO NOT OPERATE" tags on start buttons, control panels, or equipment. Treat these with the same respect as locks.
- Barriers or barricades around equipment: Caution tape, cones, or barriers may surround locked-out equipment to keep unauthorized personnel away.
- Signs posted on or near equipment: "LOCKOUT IN PROGRESS," "MAINTENANCE IN PROGRESS - DO NOT OPERATE," or similar warnings.
- Workers performing maintenance: If you see maintenance or service personnel working on equipment, assume it's locked out even if you don't see the locks.
- Assume it IS locked out and don't touch it
- Contact your supervisor before operating any equipment
- Look for locks, tags, or workers before starting equipment
- Read all warning signs and tags
1. Contact the person named on the tag (if visible)
2. Contact your supervisor or maintenance supervisor
3. Find out when equipment will be available
4. Plan alternative work or wait
5. Never remove locks or attempt to operate equipment
Authorized employees will remove their locks when work is complete and equipment is safe to operate.
Restoring Equipment to Service
Safely re-energizing equipment
For awareness: Removing locks and restarting equipment is just as critical as applying them. Only authorized employees can perform these steps.
Inspect the Work Area
Ensure all tools, materials, and equipment have been removed. Verify all guards, safety devices, and covers are properly reinstalled. Check that no one is in or near the equipment. Confirm work is complete.
Notify Affected Employees
Inform all employees that lockout is being removed and equipment will be re-energized. Ensure everyone is clear of the equipment and aware it's about to start. Give adequate warning time.
Remove Lockout/Tagout Devices
Each authorized employee removes their own lock and tag in reverse order of application. Verify all locks have been removed by all workers. Return energy isolation devices to operating positions.
Re-Energize and Test
Restore energy following proper startup procedures. Test equipment for proper operation. Verify all functions work correctly. Ensure no damage or hazards remain before releasing equipment for production use.
Only a designated manager or supervisor can remove someone else's lock under strict emergency procedures:
- Attempt to contact the employee
- Verify the employee is not at the facility
- Inspect equipment to ensure work is complete
- Have another authorized employee verify it's safe
- Document the removal in writing
- Inform the employee before they return to work
Real LOTO Failures and Lessons
Learning from tragic mistakes
These real incidents (details changed for privacy) show what happens when LOTO is bypassed or performed incorrectly:
Lesson: Never remove someone else's lock. Always verify the person who applied the lock knows it's being removed. Locks represent lives, not inconveniences.
Lesson: Locks must stay on until ALL work is complete. No "quick tests" or "temporary" removals. If equipment needs testing, stop work, remove all workers, follow full lockout removal procedures, test, then restart LOTO before resuming work.
Lesson: Identify ALL energy sources, including stored energy. Pressure must be released, capacitors discharged, springs released, and elevated components blocked or lowered. Verification testing is critical.
Lesson: Each person must apply their own lock. Never work under someone else's protection. Never assume equipment is locked out—verify it yourself.
Common thread: In every case, people thought they could skip steps or bend rules "just this once." LOTO procedures exist because the consequences of failure are deadly. There are no shortcuts in energy control.
Your Responsibilities
What every employee must do
Regardless of your employee classification, you have important responsibilities that protect yourself and your coworkers:
Respect All Lockout/Tagout Devices
Treat every lock and tag as if it's protecting someone's life—because it is. Never remove, bypass, or defeat LOTO devices. Never operate equipment that has locks or tags on it. When you see locks or tags, stay away.
Know Your Limits
If you're not trained and authorized to perform LOTO, don't attempt it. Don't work on equipment unless you're qualified. Don't assume you know how to lock out equipment "because it seems simple." Ask for help if unsure.
Communicate
If you need locked-out equipment, talk to the person who locked it out (name on tag). Coordinate with supervisors about when equipment will be available. Never try to rush or pressure someone to remove their lock early.
Report Problems
Report damaged or missing LOTO devices immediately. Report equipment that needs service. Report any violations of LOTO procedures you witness. Report "near misses" where someone almost restarted locked-out equipment.
Follow Training
Attend all required LOTO training. Ask questions if procedures are unclear. Request retraining if you're unsure about anything. Stay current on your employer's specific LOTO procedures—they may differ from this general training.
LOTO Key Takeaways
Remember these critical points
Essential LOTO knowledge for all employees:
- LOTO controls hazardous energy during service and maintenance to prevent unexpected startup, energization, or stored energy release
- Eight types of energy require control: electrical, mechanical, pneumatic, hydraulic, thermal, chemical, gravitational, and others
- Three employee types: Authorized (can perform LOTO), Affected (work in LOTO areas), Other (general awareness)
- Six LOTO steps: Preparation, Notification, Shutdown, Isolation, Lockout/Tagout, Verification
- Never remove someone else's lock or tag—this is the #1 rule that protects lives
- Never operate locked-out equipment—even if you need it urgently, wait for proper removal
- One person, one lock—each worker must apply their own individual lock
- Locks stay on until work is complete—no temporary removals or "quick tests"
- Recognize LOTO in progress—red locks, tags, barriers, and warning signs mean stay away
- Stored energy is dangerous—turning off power doesn't make equipment safe; all energy must be isolated and dissipated
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