Group Lockout Tagout Procedure: Step-by-Step Guide

Estimated Reading Time: 9 minutes

TL;DR: A group lockout tagout procedure protects multiple workers from hazardous energy during complex maintenance or shutdowns. OSHA 29 CFR 1910.147(f)(3) requires that every authorized employee attach their personal lock to a group lockbox – and that one primary authorized employee manages the isolation devices and keys. This guide walks you through how to set it up, run it during facility shutdowns, and manage contractors safely.

Group lockout tagout – called “group LOTO” – is the energy control procedure used when more than one authorized employee is working on the same equipment or system at the same time. Under OSHA’s 29 CFR 1910.147(f)(3), every worker must have their personal lock applied before work begins – and no single person can re-energize the system until every lock is removed. You’re managing a facility shutdown with 40 contractors on-site from six different companies. Every one of them needs protection from that same energy source. That’s exactly the scenario where group LOTO keeps people alive – and where a poorly written procedure gets people killed.

Key Takeaways

• OSHA 29 CFR 1910.147(f)(3) requires a designated primary authorized employee to manage group LOTO coordination
• Every worker must apply their own personal lock to the group lockbox or hasp before work begins
• Group LOTO must provide each worker with the “same protection” as individual LOTO
• Contractor LOTO must be coordinated through face-to-face communication before work starts
• Annual periodic inspections of group LOTO procedures are required under 1910.147(c)(6)
• LOTO was OSHA’s 4th most cited standard in FY2025 with 2,177 violations – missing written procedures and inadequate training are the top issues

---

What Is a Group Lockout Tagout Procedure?

A group lockout tagout procedure is an energy control method that protects multiple authorized employees working on the same equipment or system simultaneously. It’s required by OSHA under 29 CFR 1910.147(f)(3) whenever more than one authorized employee is involved in the same servicing or maintenance task. Standard individual LOTO is straightforward – one person, one lock, one isolation point. Group LOTO is different. You have multiple workers, potentially multiple energy sources, multiple crews, and the very real risk that one person’s lock removal re-energizes a system while someone else is still exposed. The regulation requires three things from any group LOTO setup:

1. A designated primary authorized employee who applies the initial isolation locks/tags and manages the group lockbox keys
2. Personal locks from every authorized employee applied before work starts
3. Equivalent protection for every worker compared to individual LOTO

That last requirement is the one that trips people up most often. OSHA doesn’t just want compliance on paper. Every single worker in that group must be protected at the same level as if they were using individual LOTO.

---

When Is a Group Lockout Tagout Procedure Required?

Per OSHA 1910.147(f)(3), a group LOTO procedure is required when any of these conditions exist:

Situation	Group LOTO Required?
Multiple authorized employees on same equipment	Yes
Multiple energy sources on one machine	Yes
Multiple crews, crafts, or departments involved	Yes
Shift changes during ongoing work	Yes
Multiple employers (contractors) on site	Yes
Work requires a specific sequence of steps	Yes

If you’re running an annual facility shutdown – where your maintenance crew, electrical contractors, mechanical contractors, and outside vendors are all working simultaneously – group LOTO isn’t optional. It’s the law, and it’s the only procedure that actually protects everyone on site. According to OSHA’s Top 10 Most Frequently Cited Standards, LOTO ranked as the 4th most cited violation in FY2025 with 2,177 violations. OSHA estimates that improper energy control causes approximately 120 fatalities and 50,000 injuries every single year. Facility shutdowns are among the highest-risk windows in any operation. Multiple employers, time pressure, unfamiliar equipment – all of it increases the chance that someone skips a step.

---

How the Group Lockbox System Works

The group lockbox system is the most common method used to execute a group lockout tagout procedure. The OSHA LOTO eTool for group procedures confirms that each worker must affix their personal device before work begins and may only remove it when their work is complete. Here’s the basic structure: Step 1 – The primary authorized employee takes control. They isolate each energy source, apply their own lock and tag to each isolation point, then place the keys to those isolation locks inside the group lockbox. Step 2 – The lockbox is locked. The primary authorized employee places their personal lock on the lockbox itself. Now the keys are physically inaccessible to everyone. Step 3 – Every other authorized employee adds their personal lock. Before anyone touches the equipment, they add their own lock to the group lockbox hasp. The lockbox can’t be opened until every lock is removed. Step 4 – Work proceeds. Every worker is protected. No one can re-energize until every single lock is removed. Step 5 – Work is complete. Each worker removes their personal lock when their portion of work is done. The primary authorized employee removes their lock last – after confirming all workers are clear – then removes the isolation locks and restores energy. For single isolation points where a hasp is used instead of a lockbox, the primary employee applies the first lock directly to a multi-lock hasp at the isolation point. Each worker then adds their personal lock to the same hasp. Either method works as long as it’s documented in your written procedure.

Step-by-Step: Running Group LOTO During a Facility Shutdown

Complex shutdowns don’t run on luck. They run on a written procedure, clear communication, and a primary authorized employee who actually owns the process. Here’s the sequence I’ve seen work consistently in large multi-crew shutdowns: Before the shutdown:

• Write or review the machine-specific group LOTO procedure (required by 1910.147(c)(4))
• Identify and brief the primary authorized employee for each piece of equipment
• Gather all required LOTO devices – enough personal locks for every worker, group lockboxes, hasps, tags, and isolation locks to cover every energy source
• Conduct a group LOTO briefing with all authorized employees before work starts – at the equipment, not in a conference room

During the shutdown:

1. Notify all affected employees that servicing is beginning
2. Primary authorized employee shuts down and isolates all energy sources
3. Primary employee applies locks and tags to each isolation point
4. Keys to isolation locks go into the group lockbox
5. Primary employee applies their personal lock to the lockbox
6. Every other authorized employee applies their personal lock to the lockbox
7. Verify zero energy state – test the equipment, bleed off stored energy, confirm zero voltage
8. Work begins

During shift changes: Incoming authorized employees must apply their personal lock before the outgoing employee removes theirs. No gap in protection, ever. The primary authorized employee role must transfer through direct, face-to-face communication between shifts. At completion: Each worker removes their personal lock when their work is done and they are clear of the equipment. The primary authorized employee verifies everyone is clear, removes their lock from the lockbox, retrieves the isolation lock keys, removes isolation locks in the correct sequence, and notifies affected employees before re-energizing. If your lockout tagout program implementation doesn’t include a documented group LOTO procedure yet, that’s your first priority before the next complex shutdown.

---

Managing Contractors in a Group Lockout Tagout Procedure

This is where facility shutdowns get complicated. You’ve got your employees, five contractor companies on site, and every single one of them needs to be protected under your group LOTO. OSHA requires that when contractors are involved, host employers and contractors must inform each other of their respective LOTO procedures and coordinate to ensure equivalent protection. That’s 1910.147(f)(2) – not a suggestion, a requirement. Here’s what actually works in large multi-contractor shutdowns: Use a color-coded lockbox system. Some facilities use separate lockboxes for employees and contractors – red for employees, yellow for contractors. Others use a single central lockbox with enough hasps for all workers. Either approach works if it’s in your written procedure. Hold a face-to-face coordination meeting. Before any contractor touches equipment, your primary authorized employee meets with the contractor’s authorized employee. Cover your procedure, your isolation points, your verification method, and your emergency removal process. Document it in writing. Create sign-in/sign-out sheets. In large shutdowns with dozens of contractors, you cannot track personal locks by memory. A sign-in sheet recording who applied their lock and when is the only way to verify everyone is accounted for before re-energization. Assign a contractor LOTO coordinator. For large shutdowns, consider designating a second person whose only job is tracking contractor lock status – who’s on, who’s off, who’s finished, who’s still working. The real risk in contractor LOTO is assuming “they have their own procedure” without verifying it’s compatible with yours. I’ve seen facilities get cited because the contractor’s authorized employee didn’t know what a group lockbox was. That’s a failure of coordination, not the contractor. For the specific compliance gaps OSHA inspectors look for first, the lockout tagout violations guide covers the most common citation patterns in detail.

---

Annual Inspection Requirements for Group LOTO Procedures

OSHA 1910.147(c)(6)(i) requires that your energy control procedures be reviewed at least once a year by an authorized employee other than the one using the procedure. For group LOTO, that means conducting the inspection with each authorized employee who uses that specific procedure and documenting it in writing – machine name, date, employees included, and the name of the inspector. This isn’t a desk review. It’s a field exercise where you walk the procedure, verify the steps still match the actual energy sources on that machine, and confirm every authorized employee is trained and competent. Most LOTO citations happen because the written procedure exists but it’s three years out of date. Running your safety program through the Safety Management Cycle – Identify, Develop, Implement and Train, Coach and Observe, Analyze – keeps group LOTO procedures current because you’re reviewing performance data and going back to update what’s not working. For audit checklists and procedure forms to support your annual inspections, the LOTO energy control templates post has free forms you can adapt for your group LOTO process.

---

Frequently Asked Questions About Group Lockout Tagout Procedures

What is a group lockout tagout procedure?

A group lockout tagout procedure is an OSHA-required energy control method used when multiple authorized employees are working on the same equipment simultaneously. Each worker applies their personal lock before work begins, and no one can re-energize the system until every lock is removed.

What does OSHA 1910.147(f)(3) require for group LOTO?

OSHA 1910.147(f)(3) requires a designated primary authorized employee to isolate energy sources and coordinate the group lockout. Every authorized employee must affix their personal lock before work starts, and the procedure must provide the same level of protection as individual LOTO.

Who is the primary authorized employee in a group lockout?

The primary authorized employee is the person designated to coordinate the group LOTO. They apply the initial isolation locks, place the keys in the group lockbox, and remove the final locks only after all other workers have cleared the area. This person owns the process from start to finish.

How do contractors fit into a group lockout procedure?

Contractors must be coordinated through face-to-face communication before work begins. Per 1910.147(f)(2), host employers and contractors must share their respective LOTO procedures. Each contractor’s authorized employee must apply their personal lock to the group lockbox the same way every other authorized employee does.

What is a group lockbox and when is it used?

A group lockbox holds the keys to isolation locks during a group LOTO. The primary authorized employee locks the isolation keys inside, then each worker adds their personal lock to the box. The box can’t be opened until every lock is removed, preventing any single person from re-energizing equipment while others are still working.

How often do group LOTO procedures need to be inspected?

OSHA requires at least one annual inspection of every energy control procedure, including group LOTO. A different authorized employee must conduct the inspection with all employees who use that procedure, and it must be documented in writing with the machine name, date, employees included, and inspector name.

---

Now It’s Your Turn

Group LOTO is one of the most complex energy control scenarios you’ll manage as a safety professional. One worker who doesn’t understand the system, one contractor whose procedure doesn’t align with yours, one lockbox that runs out of hasp loops – any of those can put someone in serious danger. Start here this week:

1. Pull your existing group LOTO procedures and verify they match the current equipment and energy sources
2. Identify who serves as primary authorized employee on each procedure and confirm they’re trained and current on their role
3. Create a contractor coordination checklist for your next shutdown – what you require from their authorized employees before work begins
4. Schedule your annual inspection if it’s not already on the calendar

If you want free templates to support your group LOTO process – energy control forms, audit checklists, and device guides – they’re waiting for you in the All-Access Resource Library. Stop building from scratch when the tools are already there. You got this.