6.2 Lockout/Tagout Procedural Steps & Stored Energy Isolation

6.2 Lockout/Tagout Procedural Steps & Stored Energy Isolation

Machine-Specific Energy Control Procedures (1910.147(c)(4))

Under 29 CFR 1910.147(c)(4), procedures must be developed, documented, and utilized for the control of potentially hazardous energy when employees are engaged in activities covered by the standard. Procedures must clearly and specifically outline the scope, purpose, authorization, rules, and techniques to be utilized, including but not limited to:

1. A specific statement of the intended use of the procedure.
2. Specific procedural steps for shutting down, isolating, blocking, and securing machines or equipment to control hazardous energy.
3. Specific procedural steps for the placement, removal, and transfer of lockout devices or tagout devices and the responsibility for them.
4. Specific requirements for testing a machine or equipment to determine and verify the effectiveness of lockout devices, tagout devices, and other energy control measures.

---

The Single Energy Source Documentation Exception

Paragraph 1910.147(c)(4)(i) Note provides a narrow documentation exception. An employer does not need to document a written energy control procedure for a specific machine or equipment only when all eight of the following conditions exist:

1. The machine or equipment has no potential for stored or residual energy or reaccumulation of stored energy after shut down which could endanger employees.
2. The machine or equipment has a single energy source which can be readily identified and isolated.
3. The isolation and locking out of that energy source will completely deenergize and deactivate the machine or equipment.
4. The energy source is isolated from the machine or equipment and locked out during servicing or maintenance.
5. A single lockout device will achieve a locked-out condition.
6. The lockout device is under the exclusive control of the authorized employee performing the servicing or maintenance.
7. The servicing or maintenance does not create hazards for other employees.
8. The employer has had no accidents involving the unexpected activation or reenergization of the machine or equipment during servicing or maintenance.

---

The 7-Step LOTO Shutdown Sequence

Executing Lockout/Tagout requires strict compliance with a sequential 7-step shutdown protocol to establish a Zero Energy State before any servicing commences:

+---------------------------------------------------------------------------------+
|                        7-STEP LOTO SHUTDOWN SEQUENCE                            |
+---------------------------------------------------------------------------------+
| Step 1: Preparation for Shutdown (Identify energy types, hazards, & controls)   |
| Step 2: Employee Notification (Notify affected employees of impending LOTO)     |
| Step 3: Machine Shutdown (Orderly shutdown using operational controls)          |
| Step 4: Machine Energy Isolation (Operate disconnect switches, valves, blinds)  |
| Step 5: LOTO Device Application (Attach locks/tags to isolation devices)        |
| Step 6: Stored Energy Dissipation & Restraint (Bleed, vent, ground, block)     |
| Step 7: Verification of Isolation (Test start controls & electrical meters)     |
+---------------------------------------------------------------------------------+

Step 1: Preparation for Shutdown

Before an authorized employee turns off a machine or equipment, they must possess comprehensive knowledge of the type and magnitude of energy, the hazards of the energy to be controlled, and the specific method or means to control the energy.

Step 2: Notification of Affected Employees

Affected employees must be notified by the authorized employee prior to the application of lockout or tagout devices, informing them that energy control measures are being implemented.

Step 3: Machine or Equipment Shutdown

The machine or equipment must be turned off or shut down using the established, orderly procedures (e.g., depressing stop buttons, opening control switches, closing valves) to prevent hazard escalation.

Step 4: Machine or Equipment Energy Isolation

All energy isolating devices (e.g., main circuit disconnect switch, line valve, circuit breaker, blind flange) necessary to control energy to the machine must be physically located and operated to isolate the equipment from its energy sources.

REGULATORY DEFINITION: An Energy Isolating Device is a mechanical device that physically prevents the transmission or release of energy (e.g., a manually operated electrical circuit breaker, a disconnect switch, a line valve, a block). Push buttons, selector switches, and software control loops are NOT energy isolating devices under 1910.147(b).

Step 5: Lockout or Tagout Device Application

Authorized employees must attach lockout or tagout devices to each energy isolating device in the off or safe position. Lockout devices must hold energy isolating devices in a neutral or "off" position.

Step 6: Stored Energy Dissipation and Restraint

Following device application, all potentially hazardous stored or residual energy must be safely relieved, disconnected, restrained, or otherwise rendered safe:

• Hydraulic / Pneumatic: Bleed pressure lines and drain fluid/air receivers.
• Capacitors: Discharge electrical capacitors using certified grounding sticks.
• Gravitational Potential: Install mechanical safety blocks, pins, or hold-down chains on elevated rams, dies, or counterweights.
• Springs: Release spring tension or mechanically block spring-loaded mechanisms.
• Thermal: Allow thermal lines to cool and vent pressure relief lines.

Step 7: Verification of Isolation (Zero Energy State Verification)

Prior to starting work on equipment that has been locked out, the authorized employee must verify that isolation and deenergization have been accomplished:

1. Operates operating controls (push buttons, selector switches) to confirm the machine cannot be restarted. Controls must be returned to the off/neutral position after testing.
2. Performs electrical testing using a calibrated, zero-verified multimeter (Test-Verify-Test protocol under Subpart S) on electrical conductors.
3. Checks pressure gauges, sight glasses, and bleed valves to confirm zero hydraulic/pneumatic pressure.

---

Dissipating and Restraining Stored Energy Types

---

The 5-Step Machinery Restoration Sequence (1910.147(e))

Before lockout or tagout devices are removed and energy is restored to the machine or equipment, authorized employees must complete the following mandatory 5-step restoration protocol:

1. Inspect Machine and Work Area: Check the work area to ensure that non-essential items (tools, spare parts, equipment) have been removed and that machine components are operationally intact.
2. Verify Employee Positioning: Check the work area to ensure that all employees have been safely positioned or removed from the hazard zone.
3. Remove LOTO Devices: Each lockout or tagout device must be removed from each energy isolating device by the authorized employee who applied the device (subject to the emergency removal exception under 1910.147(e)(3)).
4. Notify Affected Employees: Ensure affected employees are notified that lockout or tagout devices have been removed prior to restarting the equipment.
5. Restore Energy and Start Equipment: Reenergize energy isolating devices, remove line blinds, and perform operational testing.