Saturday, November 19, 2022
NFPA 70E requires us to attempt to not do energized work and if we are asked to do energized work to document one or more of four justifications for doing the work energized and have the building or system owner sign an approval to do the work energized and accept liability for doing energized work that is not covered by one of the four justifications. The four justifications are:
1. Doing the task is infeasible if the circuit or equipment is not energized. For example: The task is to take voltage or current readings with a test instrument. It is not feasible to do this without voltage and current being present in the circuit.
2. Doing the task is part of normal operations for the equipment. For example, turning a circuit breaker on or off if the dead front is in place and the breaker has been serviced and maintained as required by the manufacture. On the other hand, if the manufacturer requires that the breaker be serviced and tested every 1600 operations or three years, whichever comes first, and the last maintenance on the breaker was 6 years ago, then simply turning on the breaker would not be considered normal operation.
3. It is infeasible to turn the power off due to the system configuration. For example, the equipment that needs to be worked on is a circuit that forms an integral part of a continuous process that would otherwise need to be completely shut down in order to permit work on one circuit or piece of equipment and doing so would create additional hazards.
4. It will create a greater hazard or introduce additional risk to de-energize the equipment.
Work can also be done energized on circuits and equipment that operate at less than 50 volts.
It is important to note that none of these justifications involve convenience, difficulty or cost. It is never an acceptable reason to do energized work just because it is more convenient, less difficult or that is less costly.
If we are not going to the work energized, then we have to put the equipment into an electrically safe work condition. Part of the process of putting equipment in an electrically safe work condition involves locking out the source of power. What we typically call lock out/ tag out or LOTO. The question is often asked, can we just put a tag on a disconnect with the appropriate information instead of a lock? Another question I am often asked is what kind of lock do need to use for LOTO? NFPA 70E answers both of these questions in article 120.
Can I use a Tag instead of a lock for LOTO? The answer is yes, but ONLY if the design of the equipment precludes the use of a lock. Some equipment manufactured prior to 1990 was made without the means to apply a lock to the equipment while it was in the open position. A Tag is permitted to be used in these cases instead of lock. Here is the exact requirement of NFPA 70E 2021. Article 120.4(B)(11)
(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.
ENHANCED CONTENT FROM THE NFPA 70E HANDBOOK
Tagout is permitted in lieu of lockout only in cases where equipment design precludes the installation of a lock. Since 1990, disconnect devices for electrical equipment have been required to be able to accept a lock to minimize the use of tagout procedures. If tagout is permitted, the procedure must clearly define the individual responsibilities and accountability for each person that might be exposed to an electrical hazard. In addition, all employees must receive training on the limitations of tags.
What kind of lock do I need to use for LOTO?
NFPA 70E also answers this question by requiring the use of a keyed or combination lock. Here are the exact requirements for both locks and tags from NFPA 70E Article 120.3 (C) and (D)
(C) Lockout Device.
The lockout device shall meet the following requirements:
(1) A lockout device shall include a lock — either keyed or combination.
(2) The lockout device shall include a method of identifying the individual who installed the lockout device.
(3) A lockout device shall be permitted to be only a lock, if the lock is readily identifiable as a lockout device, in addition to having a means of identifying the person who installed the lock, provided that all of the following conditions exist:
(a) Only one circuit or piece of equipment is de-energized.
(b) The lockout period does not extend beyond the work shift.
(c) Employees exposed to the hazards associated with re-energizing the circuit or equipment are familiar with this procedure.
(4) Lockout devices shall be attached to prevent operation of the disconnecting means without resorting to undue force or the use of tools.
(5) Where a tag is used in conjunction with a lockout device, the tag shall contain a statement prohibiting unauthorized operation of the disconnecting means or unauthorized removal of the device.
(6) Lockout devices shall be suitable for the environment and for the duration of the lockout.
(7) Whether keyed or combination locks are used, the key or combination shall remain in the possession of the individual installing the lock or the person in charge, when provided by the established procedure.
ENHANCED CONTENT FROM NFPA 70E HANDBOOK
The additions made to item (3) of 120.3(C) for the 2021 edition help to align NFPA 70E with the requirements of 29 CFR 1910.333 of OSHA's Occupational Safety and Health Standards.
Even though a uniquely identified lock used as a lockout device can be used in conjunction with other components, the fundamental lockout device must be a lock. The lockout device must also include information that identifies the person who installed the lock and must be installed in a manner that prevents the operation of the energy isolation device.
(D) Tagout Device.
The tagout device shall meet the following requirements:
(1) A tagout device shall include a tag together with an attachment means.
(2) The tagout device shall be readily identifiable as a tagout device and suitable for the environment and duration of the tagout.
(3) A tagout device attachment means shall be capable of withstanding at least 224.4 N (50 lb.) of force exerted at a right angle to the disconnecting means surface. The tag attachment means shall be nonreusable, attachable by hand, self-locking, non-releasable, and equal to an all-environmental tolerant nylon cable tie.
(4) Tags shall contain a statement prohibiting unauthorized operation of the disconnecting means or removal of the tag.
(5) A hold card tagging tool on an overhead conductor in conjunction with a hotline tool to install the tagout device safely on a disconnect that is isolated from the work(s) shall be permitted. Where a hold card is used, the tagout procedure shall include the method of accounting for personnel who are working under the protection of the hold card.
ENHANCED CONTENT FROM NFPA 70E HANDBOOK
The work environment of utility employees often leads to the disconnecting means being located several miles away from a worksite. Utility systems have successfully relied on hold cards to provide warnings when operating a disconnecting means could place employees in danger. Utility workers are trained to respect the system associated with the hold card, which generally results in a positive and effective system of energy control.
When tagout is employed, at least one more safety measure, such as removing the cutout, must be used in addition to the use of the hold card. Employees of utility systems must be covered by a written policy that describes how the hold card system functions. Where contract employees perform utility maintenance or construction, the contract employer must provide a program that is at least as effective as the program of the utility authorizing the contractor’s work.
I encourage all electricians and electrician apprentices to own a copy of the most current NFPA 70E and to learn to use it for reference and answer safety questions. This should be as familiar to us as the National Electric Code. Our lives literally depend on it.
Ted "Smitty" Smith
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