Group Lockout/Tagout

When a crew works on a large machine or process with many energy sources, group lockout lets everyone be protected without each person locking every valve and breaker. The key rule stays the same: every worker controls their own protection with their own lock.

Photo: group lockbox with the isolation keys inside and multiple workers’ personal locks on the hasp

How it works

  1. A primary authorized employee takes responsibility for the group lockout.
  2. Energy sources are isolated and locked with lockout devices, following the written procedure.
  3. The keys to those locks go into a group lockbox.
  4. Every worker on the job puts their own personal lock (or a personal lock on a hasp) on the lockbox.
  5. Isolation is verified before work starts.
  6. When a worker finishes, they remove only their own lock. The equipment can’t be re-energized until every personal lock is off.

Rules that protect each worker

Shift changes

Lockout protection must continue across shift changes. The oncoming crew applies their locks before the offgoing crew removes theirs, following a specific procedure so there’s never a gap.

Contractors

When outside contractors work on plant equipment, the plant and the contractor must tell each other about their lockout procedures, and both crews must follow a coordinated plan. See Permit-to-Work Systems and Multi-Employer Worksites.

Removing someone else’s lock is allowed only under a strict procedure when the worker isn’t available: the employer verifies they aren’t at the facility, makes every effort to contact them, and makes sure they know before they return. Never cut a lock to “get the line running.”

Group lockout checklist

Standards & references

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