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 |