Working inside confined spaces is already risky. But when electrical or mechanical systems are involved, the danger increases fast. That’s why Lockout/Tagout (LOTO) procedures are so important, especially for electricians and mechanics who enter or work near confined spaces.
This guide explains how LOTO and confined space safety go hand in hand, with tips for controlling hazardous energy before any entry.
What Is Lockout/Tagout (LOTO)?
LOTO is a method used to control hazardous energy before performing maintenance, repair, or inspection work. This includes electricity, steam, compressed air, hydraulic systems, and moving parts that can suddenly start.
LOTO involves two parts:
- Lockout: Placing a physical lock on a machine or power source to stop it from starting.
- Tagout: Adding a warning tag with the worker’s name, contact info, and time of lockout.
These steps help protect anyone working on or near machines, especially inside confined spaces.
What Is a Confined Space?
A confined space is:
- Large enough for a worker to enter,
- Has limited ways in or out,
- Not meant for continuous work.
Common confined spaces include:
- Electrical vaults
- Utility tunnels
- Boilers
- Tanks
- Pits or manholes
- Crawl spaces
When these areas contain dangerous energy or harmful air, they become even more hazardous.
Why Electricians and Mechanics Face Higher Risks
Electricians and mechanics often work on equipment that:
- Stores high-voltage power
- Contains moving parts
- Builds pressure or heat
- Connects to remote systems that might restart automatically
Inside a confined space, it’s harder to escape quickly if something goes wrong. That’s why locking out all possible energy sources is critical before starting any work.
Common Hazardous Energy Sources
Before entering any confined space, check for these energy types:
| Energy Type | Examples |
| Electrical | Circuits, panels, motors |
| Mechanical | Gears, belts, moving shafts |
| Hydraulic | Lifts, jacks, press systems |
| Pneumatic | Air compressors, hoses |
| Thermal | Boilers, steam systems |
| Chemical | Pressure tanks, chemical pumps |
| Gravity | Suspended loads, overhead parts |
Each of these must be isolated or blocked before a worker enters.
Step-by-Step: Lockout/Tagout Before Confined Space Entry
Step 1: Identify All Energy Sources
Look at the equipment connected to the confined space. Don’t forget remote or hidden connections, such as backup power or valves.
Step 2: Shut Down Equipment
Turn off all connected machinery or systems using normal controls. This includes electrical panels, switches, and valves.
Step 3: Lock and Tag Each Energy Source
- Use an approved lock to block the control point (like a breaker or valve).
- Attach a tag with your name, department, and date.
- Use one lock per worker, no sharing.
Step 4: Release Stored Energy
- Drain pressure lines
- Discharge capacitors
- Block moving parts
- Lower raised equipment
- Bleed off steam or fluid pressure
Stored energy is often forgotten, but it can be deadly.
Step 5: Test Equipment Before Entry
Try to restart the system using the control buttons or switches. Nothing should move or power up. This confirms the lockout is effective.
Confined Space Entry Precautions for LOTO Workers
Even after locking out systems, confined space entry comes with more hazards. Here are specific tips for electricians and mechanics.
For Electricians:
- Use rated gloves and insulated tools
- Test all wires for voltage, even “dead” ones
- Be aware of arc flash zones
- Stay dry to reduce shock risk
- Watch for stored charges in capacitors or batteries
For Mechanics:
- Watch for loose or falling parts when inside tight areas
- Use blocks and pins to hold heavy parts in place
- Avoid tools that can slip or get stuck in moving parts
- Always assume a system could restart unless locked out
Special Equipment for Confined Space Work
Before entering, LOTO-certified workers should have:
- LOTO kits (locks, tags, hasps)
- Gas detectors (for oxygen levels, toxic gases)
- Communication tools (like radios or hand signals)
- Harnesses and retrieval systems
- Personal protective equipment (PPE) such as gloves, helmets, boots, and safety glasses
If working inside a permit-required confined space, a trained attendant must be outside the entry point at all times.
Don’t Forget These Common Mistakes
Even experienced workers make errors. Here are top mistakes to avoid:
| Mistake | Why It’s Dangerous |
| Not locking all energy sources | Some machines have more than one power source |
| Using the wrong type of lock | Can be bypassed or broken easily |
| Sharing locks | Makes it unclear who is inside the space |
| Removing tags early | Can lead to a restart while someone is inside |
| Skipping the test step | May miss an active power line or a hidden fault |
Training and Responsibility
LOTO rules apply to authorized employees, those trained and allowed to apply or remove locks and tags. In most companies, this includes:
- Licensed electricians
- Maintenance mechanics
- Technicians with LOTO training
Supervisors should also support the lockout process and confirm it’s being done on every confined space job.
What OSHA Says
Under OSHA’s LOTO standard (29 CFR 1910.147) and confined space standard (29 CFR 1926 Subpart AA for construction):
- All hazardous energy must be controlled before entry
- Only trained workers may apply or remove locks
- A written LOTO procedure must exist for each system
- All confined spaces must be identified and assessed before use
Violations of these rules can lead to major injuries and heavy fines.
Final Words: Keep It Locked, Keep It Safe
Lockout/Tagout is not just a formality. For electricians and mechanics working in confined spaces, it is often the only thing standing between a safe job and a deadly one.
Always follow your company’s written procedure. Don’t skip steps. Don’t work without locking out. And never enter a confined space unless you are sure every system is turned off and locked.
