The lockout/tagout (LOTO) procedure must provide guidelines on how to properly lockout/tagout the equipment. The lockout/tagout application procedure is critical for ensuring workplace safety around machines and equipment that can harbor hazardous energy. Below is a breakdown of each component of this procedure for clarity:

1. Lockout

Lockout involves placing a lock on an energy isolating device, ensuring that the equipment cannot be energized. The lock prevents the operation of the disconnecting means, such as switches or valves, and requires a key or combination to remove it. This is a physical measure that ensures no one can accidentally or intentionally energize the system while maintenance or repair activities are ongoing. Forcible removal of the lock is required to operate the disconnecting means, underscoring the robustness and integrity of this safety measure.

2. Tagout

Tagout is the practice of placing a warning tag on an energy isolating device. While it does not physically prevent the operation of the disconnecting means, it serves as a clear warning that the equipment should not be operated. The tagout device should be placed where a lockout device is installed, making it clear that the equipment is under maintenance or repair. This tag acts as a visual deterrent and must be respected to maintain safety.

3. Adaptations for Non-Lockable Devices

In some cases, the design of the equipment may not allow for a lock to be directly applied to the energy isolating device. When this occurs, the procedure mandates that these disconnecting means cannot be solely relied upon to ensure an electrically safe work condition. Additional safety measures must be applied to ensure that the equipment remains de-energized and safe for work, such as removing a fuse or blocking a switch in the off position with a physical barrier.

4. Use of Tagout Without a Lock

There are scenarios where it's not feasible to install a lock due to equipment design limitations. In these cases, tagout alone may be used, but it must be supplemented with at least one additional safety measure to enhance security. These supplementary safety measures could include:

• Blocking or securing the disconnecting means mechanically.
• Removing a critical component of the machine, such as a fuse or a handle.
• Employing a safety observer who monitors the tagged equipment to ensure it remains de-energized.

Furthermore, procedures that rely solely on tagout must establish clear responsibilities and accountability for all personnel involved. This includes defining who is authorized to place and remove tags and ensuring that all potential exposure to electrical hazards is minimized.

Responsibilities and Accountability

The procedure should explicitly outline the responsibilities of each individual involved in the LOTO process. This includes those who apply the locks and tags, those who perform the maintenance work, and any other personnel who might interact with or be near the isolated equipment. Ensuring everyone understands their role and the associated risks is crucial for maintaining an effective safety protocol.

Overall, these elements of the lockout/tagout procedure are designed to protect workers by preventing the accidental startup or energization of machinery during maintenance or repair operations. Clear, stringent, and well-followed LOTO procedures are essential for safeguarding employees in industrial settings.

Below is a sample of NFPA 70E. For the complete section, see the actual NFPA 70E text at NFPA.ORG. Once there, click on the free access link to NFPA 70E.

120.5(B)(11) Lockout/Tagout Application. The procedure shall clearly identify when and where lockout applies, in addition to when and where tagout applies, and shall address the following:

(1) Lockout shall be defined as installing a lockout device on all sources of hazardous energy such that operation of the disconnecting means is prohibited, and forcible removal of the lock is required to operate the disconnecting means.

(2) Tagout shall be defined as installing a tagout device on all sources of hazardous energy, such that operation of the disconnecting means is prohibited. The tagout device shall be installed in the same position available for the lockout device.

(3) Where it is not possible to attach a lock to existing disconnecting means, the disconnecting means shall not be used as the only means to put the circuit in an electrically safe work condition.

(4) The use of tagout procedures without a lock shall be permitted only in cases where equipment design precludes the installation of a lock on an energy isolation device(s). When tagout is employed, at least one additional safety measure shall be employed. In such cases, the procedure shall clearly establish responsibilities and accountability for each person who might be exposed to electrical hazards.

Informational Note: Examples of additional safety measures include the removal of an isolating circuit element such as fuses, blocking of the controlling switch, or opening an extra disconnecting device to reduce the likelihood of inadvertent energization.