U.S. Department of Labor Assistant Secretary for
Occupational Safety and Health
Washington D.C. 20210
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
Subject: Electrical Safety-Related Work Practices--Inspection
Procedures and Interpretive Guidelines
A. Purpose. This instruction establishes policies and provides
interpretive guidelines to ensure uniform enforcement of the
standard for Electrical Safety-Related Work Practices, 29
CFR 1910.331 through .335.
B. Scope. This instruction applies OSHA-wide.
C. References:
1. OSHA Instruction STD 1-7.3, September 11, 1990, 29 CFR
1910.147, the Control of Hazardous Energy
(Lockout/Tagout)--Inspection Procedures and
Interpretive Guidance.
2. General Industry Standards, 29 CFR 1910, Subpart S.
3. OSHA Instruction CPL 2.45B, June 15, 1989, the Revised
Field Operations Manual (FOM).
4. NFPA 70E, 1983, Electrical Safety Requirements for
Employee Workplaces.
D. Effective Dates of Requirements. All requirements of the
standard for Electrical Safety-Related Work Practices have
an effective date of December 4, 1990, except for 29 CFR
1910.332 (training), which will become effective on August
6, 1991.
E. Action. Regional Administrators and Area Directors shall
ensure that the policies and interpretive guidelines in this
instruction are followed as to the enforcement of the
standard.
F. Federal Program Change. This instruction describes a
Federal program change which affects State programs. Each
Regional Administrator shall:
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
1. Ensure that this change is promptly forwarded to each
State designee using a format consistent with the Plan
Change Two-Way Memorandum in Appendix P, OSHA
Instruction STP 2.22A, Ch-3.
2. Explain the technical content of this change to the
State designee as required.
3. Ensure that State designees are asked to acknowledge
receipt of this Federal program change in writing to
the Regional Administrator as soon as the State's
intention is known, but not later than 70 calendar days
after the date of issuance (10 days for mailing and 60
days for response). This acknowledgment must include a
description either of the State's plan to follow the
guidelines in paragraphs H., Inspection guidelines, I.,
Interpretive Guidance, and J., Enforcement/Citation
Guidance, to implement the change, or of the reasons
why this change should not apply to that State.
4. Review policies, instructions and guidelines issued by
the State to determine that this change has been
communicated to State compliance personnel.
G. Background. The standard for Electrical Safety-Related Work
Practices was promulgated on August 6, 1990, at Federal
Register, Vol. 55, No. 151 (pages 31984-32020), and
became effective December 4, 1990, except for 29 CFR 1910
.332, which becomes effective on August 6, 1991.
1. The current electrical standards in Subpart S of the
General Industry Standards cover electrical equipment
and installations rather than work practices. The
electrical safety-related work practice standards that
do exist are distributed in other subparts of 29 CFR
1910. Although unsafe work practices appear to be
involved in most workplace electrocutions, OSHA has
very few regulations addressing work practices
necessary for electrical safety. Because of this, OSHA
determined that standards were needed to minimize these
hazards.
2. The new rule addresses practices and procedures that
are necessary to protect employees working on or near
exposed energized and deenergized parts of electric
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
equipment. The new rule also promotes uniformity and
reduces redundancy among the general industry
standards. The new rule is based largely on NFPA 70E,
Part II.
3. On September 1, 1989, OSHA promulgated a generic
standard on the control of hazardous energy, 29 CFR
1910.147 (lockout/tagout).
a. That standard addresses practices and procedures
that are necessary to deenergize machinery or
equipment and to prevent the release of
potentially hazardous energy while maintenance and
servicing activities are being performed.
b. Although that rule is related to electrical
energy, it specifically excludes "exposure to
electrical hazards from work on, near, or with
conductors or equipment in electric utilization
installations, which is covered by Subpart S of 29
CFR 1910." Therefore, the lockout/tagout standard
does not cover electrical hazards.
c. The final electrical safety-related work practices
standard has provisions to achieve maximum safety
by deenergizing energized parts and, secondly,
when lockout/tagout is used, it is done to ensure
that the deenergized state is maintained.
H. Inspection Guidelines. In so far as possible the compliance
officer shall integrate inspection procedures for this
standard with those of 29 CFR 1910.147 (lockout/tagout
standard).
1. The following guidance provides a general framework to
assist the compliance officer during all inspections:
a. The employer's written procedures required under
29 CFR 1910.333(b)(2)(i) shall be reviewed to
determine if they cover the hazards likely to be
encountered.
(1) A copy of paragraph (b) of 1910.333
maintained by the employer will fulfill this
requirement.
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
(2) A copy of the written procedures for locking
and tagging required by 29 CFR 1910.147 will
also comply with this requirement, provided
those procedures address the electrical
safety hazards covered by Subpart S and
provided the procedures conform to 1910.333
(b).
(3) If the employer has chosen to utilize
procedures developed to comply with
1910.147 for electrical as well as other
hazards, the written procedures must include
steps corresponding to requirements in
Section 1910.333 for application of locks and
tags and verification of deenergized
conditions (29 CFR 1910.333(b)(2)(iii)(D)
and (b)(2)(iv)(B)).
b. Beginning August 6, 1991, the training practices
of the employer for qualified and unqualified
employees shall be evaluated to assess whether the
training provided is appropriate to the tasks
being performed or to be performed.
(1) All employees who face a risk of electric
shock, burns or other related injuries, not
reduced to a safe level by the installation
safety requirements of Subpart S, must be
trained in safety-related work practices
required by 29 CFR 1910.331-.335.
(2) In addition to being trained in and familiar
with safety related work practices,
unqualified employees must be trained in the
inherent hazards of electricity, such as high
voltages, electric current, arcing,
grounding, and lack of guarding. Any
electrically related safety practices not
specifically addressed by Sections 1910.331
through 1910.335 but necessary for safety in
specific workplace conditions shall be
included.
(3) The training of qualified employees must
include at the minimum the following:
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
(a) The ability to distinguish exposed live
parts from other parts of electric
equipment.
(b) The ability to determine the nominal
voltage of live parts.
(c) The knowledge of clearance and/or
approach distances specified in
1910.333(c).
(4) During walkaround inspections, compliance
officers shall evaluate any electrical-
related work being performed to ascertain
conformance with the employer's written
procedures as required by 1910.333(b)(2)(i)
and all safety-related work practices in
Sections 1910.333 through 1910.335. (See J.
of this instruction for clarification.)
(5) Any violations found must be documented
adequately, including the actual voltage
level.
I. Interpretive Guidance. The following guidance is provided
relative to specific provisions of the standard for
Electrical Safety-Related Work Practices:
1. Definitions: Qualified/Unqualified Persons.
a. The standard defines a qualified person as one
familiar with the construction and operation of
the equipment and the hazards involved. "Qualified
Persons" are intended to be only those who are
well acquainted with and thoroughly conversant in
the electric equipment and electrical hazards
involved with the work being performed.
(1) Whether an employee is considered to be a
"qualified person" will depend on various
circumstances in the workplace. It is
possible and, in fact, likely for an
individual to be considered "qualified" with
regard to certain equipment in the workplace,
but "unqualified" as to other equipment. (See
29 CFR 1910.332(b)(3) for training
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
requirements that specifically apply to
qualified persons.) Only qualified persons
may place and remove locks and tags.
(2) An employee who is undergoing on-the-job
training, who, in the course of such
training, has demonstrated an ability to
perform duties safely at his or her level of
training, and who is under the direct
supervision of a qualified person is
considered to be a qualified person for the
performance of those duties.
b. Where the term "may not" is used in these
standards, the term bears the same meaning as
"shall not".
c. Training requirements apply to all employees in
occupations that carry a risk of injury due to
electrical hazards that are not sufficiently
controlled under 29 CFR 1910.303 through 1910.308.
2. Scope/Coverage of the Standard.
a. The provisions of the standard cover all employees
working on, near or with premises wiring, wiring
for connection to supply, other wiring, such as
outside conductors on the premises and optical
fiber cable, where the fiber cable installations
are made along with electric conductors and the
optical fiber cable types are those that contain
noncurrent-carrying conductive members such as
metallic strength members and metallic vapor
barriers.
b. The standard does not cover qualified workers (but
does cover unqualified workers) performing work on
the following:
(1) Electric power generation, transmission, and
distribution installations located in
buildings used for such purposes or located
outdoors.
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
NOTE: Work on the specified electrical
installations is excluded, but work
on other electric equipment in the
buildings is not excluded.
(2) Communications installations covered under 29
CFR 1910.268.
(3) Installations in ships, watercraft, railway
rolling stock, aircraft, or automotive
vehicles other than mobile homes and
recreational vehicles.
(4) Installations of railways for generation,
transformation, transmission, or distribution
of electric power used exclusively for
operation of rolling stock or installations
of railways used exclusively for signaling
and communication purposes.
c. The standard for Electrical Safety-Related Work
Practices was developed to complement the existing
electrical standards. The new standard includes
requirements for work performed on or near exposed
energized and deenergized parts of electric
equipment, use of electrical protective equipment,
and the safe use of electrical equipment.
d. Exposure to unexpected electrical energy release
that could result in electric shock or burns or in
an explosion caused by an electric arc is covered
by the standard for Electrical Safety-Related Work
Practices. Safeguarding workers from other
hazards related to the unexpected release of
hazardous energy during servicing and maintenance
operations is covered by 29 CFR 1910.147, the
lockout/tagout standard.
(1) 1910.333(a)(1) requires that live parts be
deenergized before a potentially exposed
employee works on or near them. OSHA
believes that this is the preferred method
for protecting employees from electrical
hazards. The employer is permitted to allow
employees to work on or near exposed live
parts only:
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
(a) If the employer can demonstrate that
deenergizing introduces additional or
increased hazards, or
(b) If the employer can demonstrate that
deenergizing is infeasible due to
equipment design or operational
limitations.
(2) Under 1910.333(a)(2) if the employer does not
deenergize (under the conditions permitted in
1910.333(a)(1)), then suitable safe work
practices for the conditions under which the
work is to be performed shall be included in
the written procedures and strictly enforced.
These work practices are given in 1910.333(c)
and 1910.335.
(3) Only qualified persons shall be allowed to
work on energized parts or equipment.
3. Working on Deenergized Parts.
a. Circuit parts that cannot be deenergized using the
procedures outlined in 1910.333(b)(2) must be
treated as energized (as specified in 1910.333
(b)(1)), regardless of whether the parts are, in
fact, deenergized.
b. Deenergized parts are required to be locked and
tagged unless exempted under 1910.333(b)(2)
(iii)(C) or 1910.333(b)(2)(iii)(E), as discussed
below. If so exempted, either a lock or a tag is
required.
(1) If a tag is used without a lock, it shall be
supplemented by at least one additional
safety measure that provides a level of
safety equivalent to that obtained by the use
of a lock. Examples of additional safety
measures include the removal of an isolating
circuit element, blocking of a controlling
switch, or opening of an extra disconnecting
device.
(2) A lock may be placed without a tag only under
the following conditions:
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
(a) Only one circuit or piece of equipment
is deenergized, and
(b) The lockout period does not extend
beyond the work shift, and
(c) Employees exposed to the hazards
associated with reenergizing the circuit
or equipment are familiar with this
procedure.
4. Verification of Deenergization Is Mandatory. This
verification must be done by a qualified person.
a. The qualified person shall activate the equipment
operating controls or otherwise verify that the
equipment cannot be restarted.
b. Test equipment shall be used to ensure that
electrical parts and circuit elements have been
deenergized.
c. Testing instruments and equipment shall be
visually inspected for external defects or damage
before being used to determine deenergization (29
CFR 1910.334(c)(2)).
d. For circuits over 600 volts nominal, the test
equipment shall be checked for proper operation
immediately before and immediately after the test.
5. Reenergization. The following requirements shall be
met, in the order given, before circuits or equipment
are reenergized, even temporarily.
a. A qualified person shall conduct tests and visual
inspections, as necessary, to verify that all
tools, electrical jumpers, shorts, grounds, and
other such devices have been removed so that the
circuits and equipment can be safely energized.
b. Potentially exposed employees shall be warned to
stay clear of circuits and equipment prior to
reenergizing.
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
c. Each lock and tag shall be removed by the employee
who applied it. However, if the employee is
absent from the workplace, then the lock or tag
may be removed by a qualified person designated to
perform this task provided that the employer
ensures:
(1) That the employee who applied the lock or tag
is not available at the workplace, and
(2) That the employee is informed that the lock
or tag has been removed before he or she
resumes work at the workplace.
(3) That there is to be a visual determination
that all employees are clear of the circuits
and equipment prior to lock and tag removal.
6. Working On or Near Overhead Power Lines, 29 CFR
1910.333(c)(3).
a. OSHA believes that the preferred method of
protecting employees working near overhead
power lines is to deenergize and ground the
lines when work is to be performed near
them.
b. In addition to other operations, this standard
also applies to tree trimming operations performed
by tree workers who are not "qualified persons".
In this respect the exclusion in 1910.331(c)(1)
applies only to "qualified persons" performing
line-clearance tree trimming (trimming trees that
are closer than 10 feet to overhead power lines).
c. The standard does not prohibit workers who are not
"qualified persons" from working in a tree that is
closer than 10 feet to power lines so long as that
person or any object he or she may be using, does
not come within 10 feet of a power line. However,
it would require "qualified persons" to perform
the work if the worker or any object he or she may
be using will come within 10 feet of an exposed
energized part or if a branch being cut may be
expected to come within 10 feet of an exposed
energized part while falling from the tree. (See
29 CFR 1910.333(c)(3)(ii).)
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
d. The purpose for the approach distance requirements
is to prevent contact with, and/or arcing, from
energized overhead power lines. The approach
distance applies to tools used by employees as
well as the employees themselves. Table S-5 calls
for the following approach distances for qualified
employees only:
Voltage Range (AC) Minimum Approach
(phase to phase) Distance
300V and less Avoid contact
Over 300V, not over 750V 1 ft. 0 in. (30.5cm)
Over 750, not over 2kV 1 ft. 6 in. (46cm)
Over 2kV, not over 15kV 2 ft. 0 in. (61cm)
Over 15kV, not over 37kV 3 ft. 0 in. (91cm)
Over 37kV, not over 87.5kV 3 ft. 6 in. (107cm)
Over 87.5kV, not over 121kV 4 ft. 0 in. (122cm)
Over 121kV, not over 140kV 4 ft. 6 in. (137cm)
NOTE: Unqualified employees are required to
adhere to the 10 ft. minimum.
e. Employees working on or around vehicles and
mechanical equipment, such as gin-pole trucks,
forklifts, cherry pickers, garbage trucks,
cranes and elevating platforms, who are
potentially exposed to hazards related to
equipment component contact with overhead lines,
shall have been trained by their employers in the
inherent hazards of electricity and means of
avoiding exposure to such hazards.
f. The standard for Electrical Safety-Related Work
Practices can be applied with respect to
electrical hazards related to any size,
utilization or configuration of overhead power
lines in general industry; e.g., residential power
lines, remotely located overhead power lines,
temporarily rigged overhead power lines, and
overhead power lines along streets and alleys.
7. Portable Ladders. Such ladders may not have conductive
siderails in situations where the employee or the
ladder could contact exposed energized parts. All
ladders shall be in compliance with requirements of the
standards found elsewhere in Part 1910.
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
8. Conductive Apparel. Articles of jewelry and clothing
such as watch bands, bracelets, rings, key chains,
necklaces, metalized aprons, cloth with conductive
thread, or metal headgear shall not be worn if there is
a possibility of contacting exposed energized parts.
However, such articles may be worn if they are rendered
nonconductive by covering, wrapping, or other
insulating means (29 CFR 1910.333(c)(8)).
9. Housekeeping Duties. The employer has the burden to
provide adequate safeguards (such as insulating
equipment or barriers) where live parts present an
electrical contact hazard to employees who are
performing housekeeping duties. Electrically
conductive cleaning materials (such as steel wool,
metalized cloth, and silicon carbide, as well as
conductive liquid solutions) may not be used in
proximity to energized parts unless procedures are
followed which will prevent electrical contact.
10. Electrical Safety Interlocks. Interlocks found on
panels, covers and guards are designed to deenergize
circuits to prevent electric shock to persons using
equipment or performing minor maintenance or
adjustments and shall not be defeated or bypassed by an
unqualified person.
11. Cord- and Plug-Connected Equipment. Energized
equipment here means either the equipment being plugged
or the receptacle into which it is being plugged, or
both (29 CFR 1910.334(a)(5)(i)).
12. Eye and Face Protection. 29 CFR 1910.335(a)(1)(v)
requires employees to wear protective equipment for the
eyes or face wherever there is danger of injury to the
eyes or face from electric arcs or flashes or from
flying objects resulting from electrical explosion.
13. Insulated Tool. This means a tool encased within
material of composition and thickness that is
recognized as electrical insulation.
OSHA Instruction STD 1-16.7
JUL 1, 1991
Directorate of Compliance Programs
J. Enforcement/Citation Guidance.
1. A deficiency in the employer's program that could
contribute to a potential exposure capable of producing
serious physical harm or death shall be cited as a
serious violation.
2. The failure to train "qualified" and "unqualified"
employees as required for their respective
classifications shall normally be cited as a serious
violation.
3. Paperwork deficiencies in the safe work practice
program where effective safe work practice procedures
are in place shall be cited as other-than-serious.
Gerard F. Scannell
Assistant Secretary
DISTRIBUTION: National, Regional, and Area Offices
All Compliance Officers
State Designees
7(c)(1) Project Managers
NIOSH Regional Program Directors