Preventative Maintenance - Effective Building Maintenance: Protection of Capital Assets - page 70

While NFPA 70, NationalElectricalCode , is applicable primarily to
designers, every electrical maintenance staffer should have a basic “work-
ing knowledge” of this standard as it requirements also apply to electrical
repairs and replacements.
NFPA 70B-2006, RecommendedPracticeforElectricalEquipmentMainte-
nance , includes Chapter 7 on “Personnel Safety” that relies heavily on NFPA
70E and the appropriate OSHA safety-related documents, which should be
followed for the development of programs and procedures associated with
maintenance activities. Section 70B-7.1.2 states, “Personnel safety should
be given prime consideration in establishing maintenance practices, and
the safety rules should be instituted and practiced to prevent injury to per-
sonnel, both persons who are performing tasks and others who might be
exposed to the hazard. The principal personnel danger from electricity is
that of shock, electrocution, and/or severe burns from the electrical arc or
its effects, which can be similar to that of an explosion.”
A key element with regard to personnel safety is first determining
what constitutes a qualified person. As noted in Section 70B-7.1, “Mainte-
nance should be performed only by qualified personnel who are trained
in safe maintenance practices and the special considerations necessary to
maintain electrical equipment. These individuals should be familiar with
the requirements for obtaining safe electrical installations.” Equally im-
portant is “the qualified person should determine if the hazard exposure
is limited and restricted against those not qualified for the particular task
so a person not qualified for a specific task, even though fully qualified in
all other ways, should not be exposed to the hazard of that specific task,”
as outlined in 70B-7.2.2.1.
Training is another key element in the revised document, as “all em-
ployees should be trained in safety-related work practices and required
procedures as necessary to provide protection from electrical hazards as-
sociated with their respective jobs or task assignments,” as noted in 70B-
7.3.
Key steps in establishing an electrically safe work condition are
identified in 70B-7.4.2, including:
1. Determine possible sources of electrical supply to the specific
equipment.
2. After properly interrupting the load current, open the disconnecting
device(s) for each source.