LOTO Procedure: A Complete Guide to Lockout Tagout for Workplace Safety
Accidental machine start-up is one of the most common causes of serious workplace injuries in industries such as manufacturing, construction, utilities, and maintenance. Many incidents occur not because machines are faulty—but because energy sources were not properly controlled during servicing or repair.
This is exactly why the LOTO procedure (Lockout Tagout) exists.
If you are a safety officer, maintenance engineer, supervisor, or employer, understanding the LOTO procedure step by step is essential—not just for compliance, but for saving lives.
This article explains the LOTO procedure in simple terms, with real-world context, actionable steps, and best practices.
What Is a LOTO Procedure?
The LOTO procedure is a systematic safety process used to isolate and control hazardous energy during maintenance, cleaning, servicing, or repair of machines and equipment.
LOTO stands for:
Lockout – Physically locking energy-isolating devices
Tagout – Clearly tagging the lock to warn others not to operate the equipment
The goal is simple:
✅ Ensure machines cannot start unexpectedly
✅ Prevent release of stored or residual energy
✅ Protect workers from electrocution, crushing, burns, or amputations
Why Is the LOTO Procedure Important?
Without a proper lockout tagout procedure, workers are exposed to:
Unexpected machine start-up
Electrical shock
Hydraulic or pneumatic pressure release
Mechanical movement of parts
Serious injuries or fatalities
Real-World Impact
Many workplace accident investigations reveal one common cause:
“Equipment was believed to be isolated but was not properly locked or verified.”
A well-implemented LOTO procedure eliminates this assumption risk.
Types of Hazardous Energy Controlled in LOTO
| Energy Type | Examples |
|---|---|
| Electrical | Power supply, capacitors |
| Mechanical | Rotating shafts, flywheels |
| Hydraulic | Pressurized fluids |
| Pneumatic | Compressed air |
| Thermal | Steam, hot surfaces |
| Chemical | Chemical reactions, pipelines |
| Gravitational | Raised machine parts |
Step-by-Step LOTO Procedure (Standard Method)
Step 1: Preparation for Shutdown
Identify all energy sources connected to the equipment
Understand machine drawings and operating manuals
Inform affected employees about the shutdown
✅ Planning prevents missed energy sources
Step 2: Equipment Shutdown
Switch off the machine using normal operating controls
Follow standard shutdown procedures
✅ Machine must be fully stopped before isolation
Step 3: Isolation of Energy Sources
Disconnect power supplies
Close valves
Block mechanical movement
✅ Equipment must be separated from all energy sources
Step 4: Apply Lockout and Tagout Devices
Attach lockout devices to isolators
Each authorized worker applies their own personal lock
Attach a tag with:
Name
Department
Date
Reason for lockout
✅ One lock = one worker = full accountability
Step 5: Release Stored or Residual Energy
Discharge capacitors
Relieve hydraulic or pneumatic pressure
Block moving parts
✅ Stored energy is often the most dangerous
Step 6: Verification (Try-Out Step)
Attempt to start the equipment using normal controls
Confirm that the machine does NOT operate
✅ Never skip verification – it saves lives
Step 7: Perform Maintenance or Servicing
Complete work safely while equipment remains locked
Locks must stay in place throughout the task
Step 8: Removal of Lockout Tagout
Ensure work is completed
Inspect area for tools and personnel
Remove locks only by the person who applied them
Inform affected employees before restart
✅ Controlled restart prevents secondary incidents
LOTO Procedure Flow Table
| Stage | Key Action | Responsibility |
|---|---|---|
| Preparation | Identify energy sources | Authorized person |
| Shutdown | Stop machine | Operator |
| Isolation | Disconnect energy | Authorized person |
| Lock & Tag | Apply lock + tag | Each worker |
| Energy Release | Neutralize stored energy | Authorized person |
| Verification | Test isolation | Authorized person |
| Work Execution | Maintenance task | Assigned team |
| Restart | Safe re-energization | Supervisor |
Common LOTO Procedure Mistakes (And How to Avoid Them)
❌ Using tags without locks
❌ One lock used for multiple workers
❌ Skipping stored energy release
❌ Not verifying isolation
❌ No written LOTO procedure
✅ Solution:
Written LOTO procedures
Worker training
Periodic audits
Proper lockout devices
When Is LOTO Required?
LOTO procedures must be used when:
Servicing machines
Performing preventive maintenance
Cleaning or replacing parts
Clearing jams
Repairing energized equipment
If any employee could be injured by unexpected energy release, LOTO is required.
LOTO Procedure vs Permit to Work (PTW)
| Aspect | LOTO Procedure | Permit to Work |
|---|---|---|
| Purpose | Energy isolation | Activity authorization |
| Focus | Machine safety | Overall task control |
| Requirement | Mandatory for hazardous energy | Used for high-risk tasks |
| Ownership | Maintenance & safety | Management & supervision |
✅ Best practice: LOTO + PTW together
Who Needs Training on LOTO Procedures?
LOTO training is essential for:
Maintenance technicians
Electricians
Machine operators
Safety officers
Supervisors
Training ensures:
✔ Correct application
✔ Legal compliance
✔ Reduced accidents
Frequently Asked Questions (FAQs)
LOTO stands for Lockout Tagout, a safety procedure to control hazardous energy during maintenance.
Yes. LOTO is required under most occupational health and safety regulations worldwide whenever hazardous energy is present.
Only in rare cases where locking is not possible—and only with additional safety controls. Lockout is always preferred.
Only the person who applied the lock, except under a clearly documented emergency procedure.
At least annually or whenever equipment or processes change.
Final Thoughts: LOTO Is Not Paperwork—It’s Protection
A LOTO procedure is not just a document for audits. It is a life-saving system that protects workers from invisible but deadly hazards.
Organizations that implement effective lockout tagout procedures experience:
Fewer accidents
Better compliance
Higher workforce trust
Strong safety culture
If your workplace uses machines, energy sources, or maintenance teams, LOTO is non-negotiable.
Control energy. Protect lives. That is the purpose of the LOTO procedure.
