All persons installing a LOTO device shall sign their names and the date on the tag. For a complex LOTO the name of the individual or person in charge will be identified in the plan along with procedures for maintaining contact with that individual. When preparing for LOTO, all disconnecting means shall be identified and located to ensure that energy is interrupted by a physical break and not de-energized by a circuit interlock. This shall be accomplished by reviewing current diagrammatic drawings or other means, tags, labels, and signs. Each disconnecting means shall be evaluated to determine adequacy of their interrupting ability. Based on the evaluation, it will be determined if verification of a visible open point is possible, or if other precautions are needed. Work activity where any personnel might be exposed to sources of electrical energy hazards will be identified. It will be determined if there are any other energy sources in the area where employees may be exposed to other types of energy. Energy control methods will be established for all hazardous energy sources. A voltage detector rated for voltage to which employees may be exposed will be selected for the operation. A procedure will be established for each operation to determine that the voltage detector is operating properly. The possibility of induced voltages or stored electrical energy will be identified. Grounds will be applied as needed before touching conductors or circuit parts.
The following identifies the basic steps for LOTO. In addition to these steps, it shall be determined whether a Simple or Complex LOTO can be performed. The Complex LOTO plan shall address any additional steps required. A Complex LOTO will be performed when any of the following exist:
- Multiple energy sources (more than one)
- Multiple crews
- Multiple crafts
- Multiple locations
- Multiple employers
- Unique disconnecting means
- Complex or particular switching sequences
- Continues for more than one shift, that is, new workers
Notify employees a lockout (tagout) is going to be implemented and the reason. A qualified employee knowledgeable of hazards associated with electrical energy shall implement the lockout (tagout). He/She shall know the location of disconnecting means for all sources of electrical energy and stored energy. All machinery operating on the circuit shall be shut down in accordance with manufactures recommended shutdown procedure to avoid increased hazards associated with equipment stoppage. A qualified person shall de-energize and disconnect the electric supply and relieve all stored energy. All disconnecting means will be locked/ tagged out with lockout (tagout) devices, isolating devices shall be physically located and operated to ensure machinery and equipment are isolated from its energy source.
Where only a tag is used because equipment is incapable of being locked out, additional safety measure will be used to prevent re-energization. Example: Removing the positive lead. To determine that operation is prohibited, the person applying the LOTO shall attempt to operate the disconnecting means.
A voltage-detecting instrument shall be used to verify isolation and de-energization of equipment to be worked on. Inspect the device and do not proceed if it is damaged. Secure an undamaged device and proceed.
Verify proper
operation of the device and test for absence of voltage. Repeat
verification of device after testing
for absence of voltage. Where
needed, install grounds
on the phase conductors or circuit parts, to eliminate
induced voltage or stored energy. Where it has been determined that contact with other exposed
energized conductors or circuit parts is possible,
apply ground connecting devices rated for the available
fault duty.
The following identifies the basic steps for removing a LOTO.
- Visually verifies work is complete.
- Clean up and remove all tools, equipment, and unused materials.
- Remove all grounds.
- Notify all personnel involved that the lockout (tagout) is complete, electrical energy will be restored, and to remain clear of equipment and electrical energy.
- Perform quality control checks.
- Remove lockout (tagout) devices (This must be done by the person(s) who installed them.
- Notify the owner that the equipment and/or electrical supply is ready to be returned to normal operation.
- Return the disconnecting means to their normal condition.
Each person shall install his/her own personal lockout (tagout) device for all simple LOTO operations where more than one person is involved.
When the lockout (tagout) extends for more than one day, the lockout (tagout) shall be verified to be still in place at the beginning of the next day. Where the lockout (tagout) is continued on successive shifts, the lockout (tagout) is considered to be a complex lockout (tagout).
When multiple people are working under a group LOTO there shall be a “person in charge” who has the responsibility of:
- Maintaining a “master” lock that will only be removed when affected and authorized employees are clear.
- Maintain a lock box containing the keys for the individual LOTO devices in use and only release keys to the individuals who applied the LOTO and only when all affected and authorized employees are clear.