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Electric Power >> Hazardous Energy Control >> Lockout/Tagout: Generation

Hazardous Energy Control
Lockout/Tagout: Generation

Lockout tagoutLockout/Tagout (LOTO) requirements for power generation are contained in 1910.269(d). These requirements are nearly identical to the general industry standard for LOTO (1910.147). Additionally, paragraph 1910.269(d) covers electrical energy control practices similar to the lockout and tagging provisions contained in 1910.333.

However, installations in electric generation plants that are not an integral part of, or are not commingled with, power generation processes or equipment are covered by 1910.147 and Subpart S. Refer to Appendix A of the "269" Directive CPL 02-01-038 for the definition of commingled. Requirements for Employers. The "269" standard requires power-generating authorized employees to use:
  • Lockout or, under certain circumstances described in the standard, tagout during equipment servicing and maintenance work.

    1910.269 Photo credit: Oak Ridge National Laboratory See: 1910.269(d) on hazardous energy control (lockout/tagout procedures) for power generation
     
  • Personal LOTO devices and group LOTO methods and procedures to adequately protect workers from hazardous energy.
In terms of LOTO program management, employers must:
  • Develop, document, and use energy control procedures that comply with 1910.269.
     
  • Provide compliant lockout or tagout devices.
     
  • Establish worker training programs based on the organization's energy control procedures so that workers acquire the necessary skills to safely control hazardous energy.
     
  • Conduct periodic inspections to ensure that: 1) the energy control procedure complies with the 1910.269(d) standard, and 2) the procedure is known by and is being followed by workers. The periodic inspections must be certified by the employer.
Worker-Related Requirements
  • Workers must understand and comply with their responsibilities under the energy control program.
     
  • All authorized employees also must have a job briefing that includes a review of the energy hazards associated with the job and the methods to control the energy. [Hazard Assessment and Job Briefing]
     
  • Any worker that demonstrates during routine supervisory observations or the regularly scheduled inspection that he or she does not know or is not following the energy control procedures must be retrained.
Taking Equipment Out of Service
Generating plants typically have two major work units: maintenance and operations. These units must coordinate closely when taking a piece of equipment out of service through a formal and orderly process that involves pre-shutdown planning and preparation. Typically, maintenance personnel request that a piece of equipment be taken out of service. Operations personnel, who are more familiar with the equipment and operations, usually determine the specific isolation steps required, complete the steps, install the required LOTO devices, and verify that all of the energy (including stored energy) has been released. An example of such a procedure that is compliant with the group LOTO and shift transfer provisions of 1910.269(d)(8)(ii) and (iii) may be found in Chapter 4 of the OSHA Directive CPL 02-00-047, (2008, February 11). The actions listed below must be performed in the following sequence before servicing and maintenance work may be performed on equipment:

Step 1 Prepare for shutdown – authorized employees must know the type and magnitude of the energy, the hazards involved, and the means to control the energy.
Step 2 Shut down the equipment in an orderly and safe manner.
Step 3 Operate all isolating devices (valves or switches) to deenergize the equipment.
Step 4 Attach all LOTO devices to the energy isolating devices (and, if appropriate, personal LOTO devices to group LOTO mechanisms).
Step 5 Release all stored energy (electric charge, pressure, charged springs, etc.).
Step 6 Verify that equipment energy isolation has been accomplished.

Notify affected employees of the application of LOTO devices before applying controls. (Notification of workers as the second step, before shutdown of equipment, is a best practice.)

Release from Lockout/Tagout
When the work is completed, each worker must take another personal action to indicate that he or she is no longer working under the clearance conditions. This action, along with checking the workplace area and making sure that workers are clear of the potential danger areas, includes removing the personal lockout or tag device and notifying affected employees that the LOTO devices have been removed. All individuals must complete these actions before a lead person can authorize re-energizing the equipment.

The following are additional highlights of the 1910.269(d) standard.

Lockout versus Tagout
Lockout (LO) is a surer method of assuring deenergization and control of hazardous energy sources than tagout (TO) because a LO device physically restrains energy isolating devices, whereas a TO device is merely a prominent warning device. Employers may choose to use TO devices instead of LO devices when isolating devices cannot accept a LO device. Additionally, LO is preferred, but an employer may use TO on a lockable energy isolating device if the facility's comprehensive TO program provides employee protection equivalent to a LO program. [See 1910.269(d)(2)(ii)].

Lockable Energy Isolating Devices
Any energy isolating device (valve, switch, etc.) installed after November 1, 1994, must be designed to accept a lockout device that holds it in the off or safe position and prevents operation. Any energy isolating device that has been replaced, renovated, overhauled, or modified since November 1, 1994, must also be able to accept a lockout device. An energy isolating device is considered capable of being locked out if it: 1) is designed with a part to which a lock can be attached; 2) has a locking mechanism built-in; or 3) can be externally locked, such as using a chain/lock assembly, a lockable valve cover, a circuit breaker LO, or fuse block-out devices.

Tags Plus – Full Employee Protection
If an employer chooses to design and implement a TO program, all of the TO-related provisions of 1910.269(d) must be addressed together with the Full employee protection measures, also known as Tags plus. For example, a TO device may be applied to a lockable disconnect switch if another independent control measure, such as opening a second disconnect switch or removing a valve handle, is implemented. This redundant control measure is designed to protect a worker from injury or death through the inadvertent activation of the primary control switch due to human error, inadvertent contact, or the loss or detachment of a tag. These additional control measures must be an integral part of the energy control program.

Group LOTO Methods
Group LOTO is required when more than one worker is engaged in the performance of servicing and/or maintenance activities. The hazardous energy control procedures used in group LOTO situations must provide each authorized employee with the same level of control that he or she would be afforded in an individual LOTO scenario. Each worker in a group needs to affix his or her personal LOTO device as part of the group LOTO process because the core concept of LOTO is personal control of the equipment energy sources through the application and removal of LOTO devices. Verbal accountability methods are not acceptable because they do not afford protection equivalent to that provided by the implementation of a personal LOTO device. (See 1910.269(d)(8)(ii).)

The employer may designate a primary authorized employee with the primary responsibility for a set number of workers working under the group LOTO device(s). The primary authorized employee must implement and coordinate activities related to the control of hazardous energy sources and verify that the steps taken, in accordance with the specific energy control procedure, have in fact isolated the machine or equipment effectively from the hazardous energy sources. This must be accomplished before authorized employees participating in the group LOTO affix their personal lockout or tagout device to the group LOTO box and before they perform servicing/maintenance activities. As in all situations, all authorized employees must be given an opportunity to verify energy isolation.

In addition to the primary authorized employee, each authorized employee participating in the group LOTO must be informed of their right to verify the effectiveness of the lockout measures, and each authorized employee must be allowed to personally verify that hazardous energy sources have been effectively isolated, if they so choose. An authorized employee who opts to verify the effectiveness of the isolation measures must perform this verification after affixing his or her personal lockout or tagout device to the lock box and before performing servicing/maintenance activities.

Hazardous Energy Control: General Requirements
Energized vs. Deenergized Work
Hazard Assessment and Job Briefing
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