Lockout/tagout (LOTO) procedures are essential for machinery maintenance and energy isolation to prevent unexpected energization or release of stored energy, which could cause injury to employees. These procedures involve affixing lockout devices or tagout devices to energy-isolating devices and disabling machines or equipment. [1]

Key components of LOTO procedures and safety requirements include:

• Energy Control Program: Employers must establish a program that includes energy control procedures, employee training, and periodic inspections.
• Hazardous Energy Control Procedures: Procedures must clearly outline the scope, purpose, authorization, rules, and techniques used to control hazardous energy.
• Lockout/Tagout Devices: Locks, tags, chains, wedges, or other hardware must be provided by the employer for isolating, securing, or blocking machines from energy sources.
• Training: Authorized employees must be trained on hazardous energy control procedures and the hazards involved. Affected employees should be instructed on the purpose and use of energy control procedures.
• Periodic Inspections: The employer must conduct periodic inspections of the energy control procedure at least annually to ensure the procedure and requirements are followed.

[8] [2] [2] [13] [14] The typical sequence of LOTO is:

• Preparation for Shutdown: The authorized employee must understand the type and magnitude of energy, its hazards, and the methods to control it.
• Machine or Equipment Shutdown: Shut down the machine using established procedures to avoid additional hazards.
• Machine or Equipment Isolation: Isolate the machine from all energy sources by operating energy-isolating devices.
• Lockout/Tagout Device Application: Affix lockout or tagout devices to each energy-isolating device.
• Stored Energy: Relieve, disconnect, restrain or render safe all potentially hazardous stored or residual energy.
• Verification of Isolation: Verify that the machine is isolated and de-energized before starting work.

[5] [5] [5] [5] [4] [4] Additional considerations:

• Group Lockout/Tagout: When a crew performs servicing/maintenance, use a procedure that provides equivalent protection to a personal lockout/tagout device.
• Shift Changes: Use specific hazardous energy control procedures during shift changes to ensure continuous protection.
• Outside Personnel: On-site and outside employers must inform each other of their respective LOTO procedures and ensure compliance.
• Periodic Inspections: Conducted annually by an authorized employee to evaluate the continued effectiveness of energy control procedures.

[9] [11] [3] [13] Before removing lockout or tagout devices and restoring energy:

• Inspect the work area to ensure nonessential items are removed and machine components are intact.
• Ensure all employees are safely positioned or removed from the work area.
• Notify affected employees that the lockout or tagout devices have been removed.
• Each lockout or tagout device shall be removed from each energy isolating device by the employee who applied the device.

[4] [12] [12] [12] In situations where lockout is not possible, tagout systems can be used if they provide full employee protection, such as additional safety measures like removing an isolating circuit element or blocking a controlling switch. Tagout devices must warn against hazardous conditions if the machine is energized and include a legend such as "Do Not Start, Do Not Open, Do Not Close, Do Not Energize, Do Not Operate". [7] [7] [14]

For repetitive process machines requiring power to maintain indexing, specific precautions must be followed, including constant control by a qualified operator and ensuring all participants are out of reach of moving machine elements. [10]

The employer should provide LOTO equipment, such as accident prevention signs, tags and padlocks. Signs and tags must be readily secured to controls, with tags designed for single-use, attachable by hand, self-locking, and non-releasable with a minimum unlocking strength of 50 pounds. [6]