What lockout/tagout is matters less than the order it happens in. OSHA 1910.147(d) prescribes a fixed application sequence, and incident investigations keep finding the same pattern: the isolation was textbook, and the injury came from the skipped verification or the stored energy nobody released.
This guide walks the six steps in order, the verification methods that prove zero energy, and the restart sequence that returns equipment to service safely.
The six steps in order
Every machine-specific procedure follows the same backbone. Memorize the order — it is the order an inspector will ask a tech to recite:
- 1. Prepare and notify — identify every energy source and isolation point, then tell affected employees the equipment is coming down and why
- 2. Shut down — stop the machine with its normal operating controls, never the disconnect as a stop button
- 3. Isolate — operate each energy-isolating device: open disconnects and breakers, close valves, blank lines, unplug where the procedure specifies
- 4. Apply locks and tags — every authorized worker applies a personal lock (and tag) at each isolation point or the group lockbox
- 5. Release stored energy — bleed, vent, discharge, block, or cool until residual energy is controlled
- 6. Verify zero energy — prove the machine is dead before hands go in
Steps 1–2: notify, then shut down normally
Notification prevents the most human failure in LOTO: someone restarting equipment they did not know was under service. Name who was told — operators, adjacent cells, the next shift — in the job record.
Shut down through the normal stopping sequence so the machine parks in its expected state. Yanking the disconnect under load arcs contacts, strands the machine mid-cycle, and can leave stored energy (a raised axis, a charged line) in a worse position than a controlled stop.
Steps 3–4: isolate everything, then lock it
Isolate every source the energy inventory lists — the obvious electrical feed and the second pneumatic drop, the gravity-fed section, the UPS-backed controls. Partial isolation is the classic multi-energy failure.
Then lock: personal locks applied by each exposed worker, tags identifying who and why. For crews, keys go in the group lockbox and every worker adds a personal lock. A lock applied by someone else protects no one.
Step 5: release what isolation leaves behind
Isolation stops new energy; only release or restraint handles what is already inside: vent receivers and trapped lines at named bleed points, bleed accumulators to tank, discharge capacitors through rated means, lower or pin raised loads, let thermal sources reach the stated safe temperature.
Write each release with its device identifier and its pass reading — "bleed accumulator A-2 at BV-4 until PG-2 reads zero" — because vague release steps ("bleed system") are the ones skipped under time pressure.
Step 6: verify zero energy — three checks, not one
Verification is a sequence, not a glance. The complete check runs three layers:
- Try-start — attempt to operate the machine with normal controls (it must not move), then return controls to off
- Test and gauge — meter electrical circuits with a rated tester, read pneumatic/hydraulic gauges at zero, confirm discharged capacitors
- Confirm restraints — blocks seated and pinned, pins and chains verified by sight and touch, temperatures measured where thermal energy applied
| Check | What it proves | Typical method |
|---|---|---|
| Try-start | Electrical isolation holds; controls dead | Operate normal start, then return to off |
| Meter / gauge | No hidden charge or pressure | Rated meter; gauges read zero |
| Restraint confirm | Gravity and springs cannot move | Blocks seated, pins through, verified by hand |
Skipped verification is the classic injury pattern. Follow Tegis on Google for step-by-step walkthroughs.
Return to service without creating the next incident
Restart has its own required sequence: confirm tools, parts, and personnel clear; reinstall guards; remove locks only by their owners (last personal lock off the box first, then equipment locks by the primary employee); notify affected employees; and restart through normal controls.
Never remove another worker lock to expedite a restart. The documented emergency-removal procedure — verifying the employee is off site — is the only exception, and using it casually is a willful-violation pattern.
Key takeaways
- Six steps, fixed order: notify, shut down, isolate, lock, release stored energy, verify.
- Verification is three checks — try-start, meter/gauge, restraint confirm — one per energy family.
- Write releases and verifications with device names and pass readings, never vague verbs.
- Restart is sequenced too: clear, guard, owner-removes-own-lock, notify, start.
- The skipped verification is the step most often behind LOTO injuries — make it a stop-work offense to omit.
Frequently asked questions
What are the six steps of lockout/tagout?
Prepare and notify affected employees; shut down with normal controls; isolate every energy source; apply personal locks and tags; release or restrain stored energy; verify zero energy before work. Return to service follows its own sequence: clear, guard, remove own locks, notify, restart.
What is the try-start check?
After lockout, attempt to start the machine with its normal operating controls. No movement confirms electrical isolation — then return the controls to off. Try-start alone does not verify stored energy; gauges, meters, and restraint checks cover the rest.
How do you verify zero energy on multi-energy machines?
One check per energy family: try-start for electrical isolation, meter readings for capacitors and circuits, gauge readings for pneumatic and hydraulic, physical confirmation for blocked gravity and springs, temperature measurement for thermal. Each gets a written pass criterion in the procedure.
Can the disconnect be used to stop the machine?
No — shut down with normal operating controls first, then open the disconnect to isolate. Using the disconnect as a stop switch arcs equipment, strands mid-cycle stored energy, and violates the required sequence.