Energy Isolation

Guide for LO/TO (Lock Out / Tag Out)

Don't be a VICTIM... Don't be a KILLER...

Purpose of Lock Out / Tag Out:

• To protect workers from the release of hazardous energy
• To guard against the accidental start-up of equipment during service and maintenance

Distinction must be made between LO/TO and various other locking practices, collectively referred to as Administrative Locking

LO/TO:

Is a specific procedure to ensure Zero-Energy in the system and allow personnel to service, maintain, or modify equipment.

Administrative Locking: 

Normally not used as the primary means of protection during a servicing, maintenance, or modification procedure, and must not be used as a substitute for LO/TO locks or LO/TO tags. It may be performed for many reasons, including equipment security, programmatic purposes, or general safety.

Examples of Administrative Locking are: 

• Locked fences around high-voltage transformers
• Locks on overhead-crane disconnect switches
• A locked door to a laboratory that contains hazardous equipment
• A water valve locked in the open position

ENERGY SOURCES

Typical sources of energy that may need to be isolated, locked and tagged out include:

• Electrical: Electric Motors and Batteries
• Hydraulic: Pressurized Fluids in hoses / pipes
• Pneumatic: Pressurized Air in hoses / pipes
• Mechanical: Gravity Systems or Spring Energy
• Chemical: Storage Vessels or Pipelines containing Toxic / Hazardous Chemicals and Hydrocarbon / Petrol products
• Thermal: Hot Oil Lines used to heat Heavy Fuel Oil Tanks / Pipe Work
• Pressurized Liquids/Gases: Hydrocarbons, Petrol and Steam

Note that LO/TO applies to more than just electrical circuits!

Definition of terms in LO/TO:

• Affected Team Member
• Refers to the Equipment operator or Equipment owner. Equipment is under repair or servicing being render and LO/TO is being used to isolate energy and prevent operator to operate the equipment.
• Authorized Team Member
• A person who locks out or tags out the machines or equipment in order to perform servicing or maintenance on that machine or equipment. Note that an Affected Team Member becomes an Authorized Team Member when that Team Member duties include performing servicing or maintenance covered under this section.
• Energized
• Connected to an energy source or containing residual or stored energy.
• Zero-Energy State
• A condition that is reached when all energy sources to or within equipment are isolated, blocked, or otherwise relieved, with no possibility of re-accumulation. Equipment is not safe to work on until it is in a zero-energy state.
• Energy Isolating Device
• A mechanical device that physically prevents the transmission or release of energy, including but not limited to the following:
• Manually operated electrical circuit breaker, disconnect switch
• Manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors, and no pole can operate independently
• Line valve, Block
• Similar device used to block or isolate energy
• Push buttons, selector switches and other control circuit type
• Hot Tap
• A procedure used in the repair, maintenance and services activities that involves:
• Welding on a piece of equipment (pipelines, vessels, or tanks) under pressure, in order to install connections or appurtenances
• It is commonly used to replace or add sections of pipeline without the interruption of service for air, gas, water, steam, and petrochemical distribution systems
• Termination to energized feeder line
• Lock Out
• The placement of lockout device on an energy-isolating device, in accordance with an established procedure, ensuring that the energy-isolating device and the equipment being controlled cannot be operated until the lockout device is removed.
• Tag Out
• The placement of a tag-out device on an energy-isolating device, in accordance with an established procedure, to indicate that the energy-isolating device and the equipment being controlled may not be operated until the tag-out device is removed.

Training and Authorization

Only employees who are trained and authorized can perform LO/TO.

1. Training
• Equipment operator and maintenance who will perform LO/TO
• Equipment Safety features
• Equipment energy supply control system
• Contractors
• May be permitted to show written records of equivalent training.
2. Authorization
• Manager provides specific authorization after the Team Member satisfies the training requirements
• Manager must ensure that the Team Member is thoroughly familiar with the equipment and the energy control procedures
• Manager shall provide additional on-the-job training if the employee is not thoroughly familiar with the equipment and/or written procedure
• Manager may authorize an employee to perform LO/TO
• This authorization stipulates the specific equipment or types of equipment on which the authorized employee may perform LO/TO
• Each manager must maintain records of authorized employees, and the type of on-the-job training
3. Reauthorization and Retraining
• LO/TO reauthorization is required when:
• An authorized employee's job changes or if he/she is reassigned
• New equipment is to be used
• New energy-control procedures are to be implemented
• LO/TO retraining and / or reauthorization is required when:
• A manager has reason to believe that an employee has inadequate knowledge of LO/TO procedures or policy
• A periodic inspection shows a deficiency in the authorized employee's ability to implement LO/TO policy correctly
4. Affected Employee Training
• Any Team Member may be near to or affected by equipment on which LO/TO is performed
• All Team Members receive LO/TO awareness training through the New Team Member Health and Safety Orientation and Training course
• All Team Members must know how to recognize LO/TO, why LO/TO is implemented, and the importance of leaving LO/TO devices in place
• Team Members are prohibited from tampering with LO/TO devices or attempting to restart equipment to which LO/TO is applied

Lock Out / Tag Out Equipments

Team members who perform LO/TO must be provided with LO/TO equipment and be properly used

1. Padlocks
• Padlocks shall be identified as being used for LO/TO:
• Maybe a red body indicates that it is being used for LOTO
• Each padlock shall be identified with the authorized Team Member Name, Section & Department
• Other means of identification (e.g., engraving) are also permissible
• A manager may appoint to utilize a checkout system that permits authorized Team Member to borrow locks from a common local supply
• In such cases, the authorized Team Member checking out a lock must re-label it with his / her name
2. Padlock Labels
• Each lock must be clearly labeled with the authorized Team Member Name, Section & Department
3. Keys
• Each LOTO padlock is required to have two keys:
• The primary key must be in the possession of the authorized Team Member who applied the lock
• The emergency key must be kept in a secured area (e.g., a lock box) with access limited to the authorized Team Member immediate manager and one level of management above the authorized Team Member manager
• A group of locks with a common key may be used for equipment with multiple energy-isolation devices, if desired
• If a group of locks is keyed alike for this purpose, First key only may be issued for use by the authorized Team Member and the Second key may be kept for emergency use
4. Tags
• The tag must always be used in conjunction with a lock unless the energy-isolating device is not physically capable of being locked
• The tag is required to be attached with a nylon locking cable tie. Protective clear plastic sleeves shall be used for outdoor applications
• The authorized employee who performs LO/TO must complete all applicable sections of the tag
5. Other Hardware
• The manager shall provide other hardware as required such as multiple lock hasps and circuit breaker and valve lockout devices

LO/TO General Procedure

1. Preparation and Notification
• Use written procedures:
• Authorized Team Member must determine if an Equipment-Specific Written Procedure is applicable to the task
• Authorized Team Member must obtain and follow the equipment- specific written procedure
• If a new written procedure must be generated, the authorized Team Member must contact his / her manager / supervisor
• Assess energy type and magnitude
• Authorized Team Member must assess the type, magnitude, and hazards of the energy to be controlled
• Determine methods of control
• Authorized Team Member must determine the appropriate methods of controlling the hazardous energy (e.g. disconnect switch or valve)
• Note that push buttons, selector switches, interlock circuits, and other control type devices are not energy-isolating devices
• Notify all affected personnel
• Authorized Team Member must notify all affected employees of the impending shutdown and the reasons for it
2. Shutdown
• Verify that it is safe to shut down equipment
• The authorized Team Member must verify that it is safe to shut down the equipment
• Perform normal equipment shutdown
• The authorized employee must turn off or shut down the equipment using established methods for that equipment
• Isolate and lock out energy sources
• Authorized Team Member must operate the energy-isolating device and install LO/TO device
• The lock must be affixed so as to hold the energy- isolating device in an off or safe position that physically prohibits normal operation of the energy- isolating device
• Write required information on tag
• The authorized TM must complete all appropriate information on the tag
• Tags should not obstruct indicator lights or controls, tag may be located as close as is safely possible to the device, in a position that will be immediately obvious to anyone attempting to operate the device
• Release stored energy
• In the case of stored mechanical energy, vent valves, spring releases, blocking devices, or equipment repositioning (as appropriate) must be utilized. In the case of approved grounding wires or discharge devices must be used
• Verify re-accumulation of energy
3. Verification of LO/TO Application Procedure
• Attempt to restart the equipment
• Authorized Team Member must physically attempt to operate the energy-isolating device and attempt to restart the equipment using the normal equipment controls (e.g., start buttons or computer software controls)
• If the equipment is electrical, test for zero energy state
• Authorized Team Member must test potential electrical energy sources using appropriate instruments or testers
• Authorized Team Member shall also determine if any energized condition exists as a result of inadvertently induced voltage or unrelated voltage back-feed even though specific parts of the circuit have been de-energized and presumed to be safe
• Only qualified Team Member can executing the energy testing
4. Release from LO/TO: Before LO/TO devices are removed and energy is restored to the equipment, the authorized Team Member must follow the procedures below:
• Verify that it is safe to re-energize
• Authorized Team Member must verify that the work for which the LO/TO was applied has been completed and that it is safe to reenergize equipment
• Clear all tools and personnel
• Authorized Team Member must check the work area to ensure that all tools and personnel are at a safe distance from the equipment
• Remove all isolating and grounding devices
• Authorized employee must remove any devices applied
• Replace safety guards
• Authorized employee must check the equipment to ensure that any removed guards are reinstalled
• Remove lock and tag, reset the energy-isolating device, and return the machinery to service
• Notify all affected personnel
• Authorized employee must notify all affected employees that the equipment is back in service
5. Temporary Removal of LO/TO Devices
• When LO/TO devices must be temporarily removed from the energy-isolating device so that the equipment or component can be energized for testing or positioning, the following sequence of actions must be taken:
• Notify the affected employees and area manager
• Clear the equipment of tools and materials
• Remove Team Member from the machine or equipment area and ensure that required tools are safely and properly positioned
• Remove all repositioned and blocking devices, return all vents and valves to their normal operating positions
• Remove all grounding / shorting conductors
• Energize and proceed with testing or positioning
• De-energize all systems and reapply lockout / tag-out measures to continue the servicing, maintenance, or modification of the equipment. The original tag may be reused
6. Emergency Removal of LO/TO Devices
• When the authorized Team Member who applied a LO/TO device is not available to remove, the manager may remove the device. This is considered to be an emergency procedure, to be undertaken only in extreme circumstances. Extreme care must be taken and the following steps must be performed:
• The manager must verify that the authorized Team Member is not at the facility
• If the Team Member location cannot be determined, no further action shall be taken
• The manager must make every reasonable effort to contact the authorized employee
• This may include a telephone call to the employee's home or other location
• If the TM is contacted, the manager must inform the Team Member that LO/TO devices will be removed
• The manager must verify that it is safe to remove the LO/TO devices
• The manager may then use the emergency key to remove the LO/TO devices, or the lock may be cut off if the key is not available
• The manager must ensure that the authorized Team Member is presented with the removed lock immediately upon returning to work, and is informed of the reasons for the emergency removal
• The emergency procedure must be duly recorded in the department's lock out / tag out records and signed by both the manager and the authorized Team Member

Procedure / Application of Group LO/TO

Install Group LO/TO Procedure

1. The manager must determine that group LO/TO is appropriate
2. The manager must convene a meeting of all members of the group to be covered under the procedure
• The manager must describe the tasks to be performed
• The manager must delegate primary responsibility to a designated authorized Team Member for a specified group of employees working under the protection of the group's LO/TO
• The structure of the group, the names of all group members and the designated authorized Team Member, and reasons for the group LO/TO must be documented in an appropriate LO/TO logbook
• Each member of the specified group must be trained and authorized
3. The designated authorized employee is responsible for ensuring that each step of the general or equipment-specific written procedure is completed
4. The designated authorized Team Member must apply his/her personal LO/TO lock(s) and tag(s) to the energy-control device(s) and indicate on the tag that a "group lockout" is in effect
5. The designated authorized Team Member must communicate to each Team member that LO/TO is in place and work may commence
• Designated authorized Team Member must inform any new group member that a group lockout is in place and communicate to all the information relating to the group lockout
• The names of the team members must be added to the log
• Anyone leaving the group before the servicing, maintenance, or modification is completed must notify the designated authorized Team Member

Releases of Group LO/TO

1. When the work is completed, the designated authorized Team Member must communicate to each group member that the group LO/TO is being considered for removal and:
• Must verify with each member that all tasks performed in conjunction with the specific job are complete
• Must verify that the equipment has been returned to a safe restart condition
2. After positive verification is received from all crew members, the designated authorized Team Member may remove the group LO/TO devices and perform equipment restart
• If any group member is not present to provide the verification that is required under Steps 1 and 2, the designated authorized Team Member must follow all the procedures as outlined
3. The designated authorized employee is responsible for making all appropriate logbook entries

Locks and Tags are normally installed in the following order:

1. Operator Lock
2. Electrician Lock
3. Maintenance Lock

Locks and Tags are normally removed in the following order:

1. Maintenance Lock
2. Electrician Lock
3. Operator Lock

Recordkeeping Requirements

Each LO/TO event must be fully documented in the department log, project log, or a dedicated LO/TO logbook

The following information must be documented: 

1. Name of authorized Team Member who performed LO/TO
2. Date and time LO/TO was applied
3. Equipment and circuit identification
4. Reason for LO/TO
5. Schematic drawing or print numbers, when available
6. Date and time of LO/TO removal
7. Name of authorized Team Member who removed LO/TO if different from authorized Team Member who initiated LO/TO

At the discretion of the manager, recordkeeping requirements may be satisfied by an orderly system of archiving completed tags. Records shall be maintained for two years

An equipment-specific written procedure is required if the equipment undergoing servicing, modification, or maintenance meets one or more of the following conditions:

1. Has more than one energy source
2. Requires the operation of more than one device to isolate the hazardous energy
3. Has potential for stored, residual, or accumulated hazardous energy
4. Is incapable of being locked out, and a second means of isolation is not possible

At least annually the manager / supervisor of an organization implementing LO/TO shall perform an inspection of the energy-control procedures. The inspection shall be conducted to identify and correct any deviations or deficiencies.

The inspection shall also document the following:

1. Identification of the machines or equipment on which the energy-control procedure was utilized
2. Date of the inspection
3. Names of employees included in the inspection
4. Name of the person who performed the inspection

Posted in: Electrical Safety