"General." Safety-related work practices shall be employed to prevent electric shock or other injuries
resulting from either direct or indirect electrical contacts, when work is performed near or on equipment or circuits which are or may be energized.
The specific safety-related work practices shall be consistent with the nature and extent of the associated electrical hazards.
"Deenergized parts." Live parts to which an employee may be exposed shall be deenergized before the
employee works on or near them, unless the employer can demonstrate that deenergizing introduces additional or increased hazards or is infeasible due
to equipment design or operational limitations. Live parts that operate at less than 50 volts to ground need not be deenergized if there will be no
increased exposure to electrical burns or to explosion due to electric arcs.
Note 1: Examples of increased or additional hazards include interruption of life support equipment, deactivation of emergency alarm
systems, shutdown of hazardous location ventilation equipment, or removal of illumination for an area.
Note 2: Examples of work that may be performed on or near energized circuit parts because of infeasibility due to equipment design or
operational limitations include testing of electric circuits that can only be performed with the circuit energized and work on circuits that form an
integral part of a continuous industrial process in a chemical plant that would otherwise need to be completely shut down in order to permit work on
one circuit or piece of equipment.
Note 3: Work on or near deenergized parts is covered by paragraph (b) of this section.
"Energized parts." If the exposed live parts are not deenergized (i.e., for reasons of increased or
additional hazards or infeasibility), other safety-related work practices shall be used to protect employees who may be exposed to the electrical
hazards involved. Such work practices shall protect employees against contact with energized circuit parts directly with any part of their body or
indirectly through some other conductive object. The work practices that are used shall be suitable for the conditions under which the work is to be
performed and for the voltage level of the exposed electric conductors or circuit parts. Specific work practice requirements are detailed in paragraph
(c) of this section.
"Working on or near exposed deenergized parts."
"Application." This paragraph applies to work on exposed deenergized parts or near enough to them to
expose the employee to any electrical hazard they present. Conductors and parts of electric equipment that have been deenergized but have not been
locked out or tagged in accordance with paragraph (b) of this section shall be treated as energized parts, and paragraph (c) of this section applies
to work on or near them.
"Lockout and Tagging." While any employee is exposed to contact with parts of fixed electric
equipment or circuits which have been deenergized, the circuits energizing the parts shall be locked out or tagged or both in accordance with the
requirements of this paragraph. The requirements shall be followed in the order in which they are presented (i.e., paragraph (b)(2)(i) first, then
paragraph (b)(2)(ii), etc.).
Note 1: As used in this section, fixed equipment refers to equipment fastened in place or connected by permanent wiring methods.
Note 2: Lockout and tagging procedures that comply with paragraphs (c) through (f) of 1910.147 will also be deemed to comply with
paragraph (b)(2) of this section provided that:
 The procedures address the electrical safety hazards covered by this Subpart; and
 The procedures also incorporate the requirements of paragraphs (b)(2)(iii)(D) and (b)(2)(iv)(B) of this section.
"Procedures." The employer shall maintain a written copy of the procedures outlined in paragraph
(b)(2) and shall make it available for inspection by employees and by the Assistant Secretary of Labor and his or her authorized
Note: The written procedures may be in the form of a copy of paragraph (b) of this section.
Safe procedures for deenergizing circuits and equipment shall be determined before circuits
or equipment are deenergized.
The circuits and equipment to be worked on shall be disconnected from all electric energy
sources. Control circuit devices, such as push buttons, selector switches, and interlocks, may not be used as the sole means for deenergizing circuits
or equipment. Interlocks for electric equipment may not be used as a substitute for lockout and tagging procedures.
Stored electric energy which might endanger personnel shall be released. Capacitors shall be
discharged and high capacitance elements shall be short-circuited and grounded, if the stored electric energy might endanger personnel.
Note: If the capacitors or associated equipment are handled in meeting this requirement, they shall be treated as energized.
Stored non-electrical energy in devices that could reenergize electric circuit parts shall be
blocked or relieved to the extent that the circuit parts could not be accidentally energized by the device.
"Application of locks and tags."
A lock and a tag shall be placed on each disconnecting means used to deenergize circuits and
equipment on which work is to be performed, except as provided in paragraphs (b)(2)(iii)(C) and (b)(2)(iii)(E) of this section. The lock shall be
attached so as to prevent persons from operating the disconnecting means unless they resort to undue force or the use of tools.
Each tag shall contain a statement prohibiting unauthorized operation of the disconnecting
means and removal of the tag.
If a lock cannot be applied, or if the employer can demonstrate that tagging procedures will
provide a level of safety equivalent to that obtained by the use of a lock, a tag may be used without a lock.
A tag used without a lock, as permitted by paragraph (b)(2)(iii)(C) of this section, shall
be supplemented by at least one additional safety measure that provides a level of safety equivalent to that obtained by 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
A lock may be placed without a tag only under the following conditions:
Only one circuit or piece of equipment is deenergized, and
The lockout period does not extend beyond the work shift, and
Employees exposed to the hazards associated with reenergizing the circuit or equipment
are familiar with this procedure.
Verification of deenergized condition. The requirements of this paragraph shall be met before
any circuits or equipment can be considered and worked as deenergized.
A qualified person shall operate the equipment operating controls or otherwise verify that
the equipment cannot be restarted.
A qualified person shall use test equipment to test the circuit elements and electrical parts
of equipment to which employees will be exposed and shall verify that the circuit elements and equipment parts are deenergized. The test shall also
determine if any energized condition exists as a result of inadvertently induced voltage or unrelated voltage backfeed even though specific parts of
the circuit have been deenergized and presumed to be safe. If the circuit to be tested is over 600 volts, nominal, the test equipment shall be checked
for proper operation immediately after this test.
"Reenergizing equipment." These requirements shall be met, in the order given, before circuits or
equipment are reenergized, even temporarily.
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
Employees exposed to the hazards associated with reenergizing the circuit or equipment shall
be warned to stay clear of circuits and equipment.
Each lock and tag shall be removed by the employee who applied it or under his or her direct
supervision. However, if this 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 that the employee who applied the lock or tag is not available at the
The employer ensures that the employee is aware that the lock or tag has been removed
before he or she resumes work at that workplace.
There shall be a visual determination that all employees are clear of the circuits and
"Working on or near exposed energized parts."
"Application." This paragraph applies to work performed on exposed live parts (involving either
direct contact or by means of tools or materials) or near enough to them for employees to be exposed to any hazard they present.
"Work on energized equipment." Only qualified persons may work on electric circuit parts or
equipment that have not been deenergized under the procedures of paragraph (b) of this section. Such persons shall be capable of working safely on
energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and
shielding materials, and insulated tools.
"Overhead lines." if work is to be performed near overhead lines, the lines shall be deenergized and
grounded, or other protective measures shall be provided before work is started. If the lines are to be deenergized, arrangements shall be made with
the person or organization that operates or controls the electric circuits involved to deenergize and ground them. If protective measures, such as
guarding, isolating, or insulating, are provided, these precautions shall prevent employees from contacting such lines directly with any part of their
body or indirectly through conductive materials, tools, or equipment.
Note: The work practices used by qualified persons installing insulating devices on overhead power transmission or distribution lines are
covered by 1910.269 of this Part, not by 1910.332 through 1910.335 of this Part. Under paragraph (c)(2) of this section, unqualified persons are
prohibited from performing this type of work.
When an unqualified person is working in an elevated position near overhead lines, the
location shall be such that the person and the longest conductive object he or she may contact cannot come closer to any unguarded, energized overhead
line than the following distances:
For voltages to ground 50kV or below - 10 feet (305 cm);
For voltages to ground over 50kV - 10 feet (305 cm) plus 4 inches (10 cm) for every 10kV
When an unqualified person is working on the ground in the vicinity of overhead lines, the
person may not bring any conductive object closer to unguarded, energized overhead lines than the distances given in paragraph (c)(3)(i)(A) of this
Note: For voltages normally encountered with overhead power line, objects which do not have an insulating rating for the voltage involved
are considered to be conductive.
"Qualified persons." When a qualified person is working in the vicinity of overhead lines,
whether in an elevated position or on the ground, the person may not approach or take any conductive object without an approved insulating handle
closer to exposed energized parts than shown in Table S-5 unless:
The person is insulated from the energized part (gloves, with sleeves if necessary, rated for
the voltage involved are considered to be insulation of the person from the energized part on which work is performed), or
The energized part is insulated both from all other conductive objects at a different
potential and from the person, or
The person is insulated from all conductive objects at a potential different from that of the
TABLE S-5 - APPROACH DISTANCES FOR QUALIFIED
EMPLOYEES - ALTERNATING CURRENT
Voltage range (phase to phase) | Minimum approach distance
300V and less ....................| Avoid Contact
Over 300V, not over 750V .........| 1 ft. 0 in. (30.5 cm).
Over 750V, not over 2kV ..........| 1 ft. 6 in. (46 cm).
Over 2kV, not over 15kV ..........| 2 ft. 0 in. (61 cm).
Over 15kV, not over 37kV .........| 3 ft. 0 in. (91 cm).
Over 37kV, not over 87.5kV .......| 3 ft. 6 in. (107 cm).
Over 87.5kV, not over 121kV ......| 4 ft. 0 in. (122 cm).
Over 121kV, not over 140kV .......| 4 ft. 6 in. (137 cm).
"Vehicular and mechanical equipment."
Any vehicle or mechanical equipment capable of having parts of its structure elevated near
energized overhead lines shall be operated so that a clearance of 10 ft. (305 cm) is maintained. If the voltage is higher than 50kV, the clearance
shall be increased 4 in. (10 cm) for every 10kV over that voltage. However, under any of the following conditions, the clearance may be
If the vehicle is in transit with its structure lowered, the clearance may be reduced to
4 ft. (122 cm). If the voltage is higher than 50kV, the clearance shall be increased 4 in. (10 cm) for every 10 kV over that voltage.
If insulating barriers are installed to prevent contact with the lines, and if the
barriers are rated for the voltage of the line being guarded and are not a part of or an attachment to the vehicle or its raised structure, the
clearance may be reduced to a distance within the designed working dimensions of the insulating barrier.
If the equipment is an aerial lift insulated for the voltage involved, and if the work is
performed by a qualified person, the clearance (between the uninsulated portion of the aerial lift and the power line) may be reduced to the distance
given in Table S-5.
Employees standing on the ground may not contact the vehicle or mechanical equipment or any
of its attachments, unless:
The employee is using protective equipment rated for the voltage; or
The equipment is located so that no uninsulated part of its structure (that portion of
the structure that provides a conductive path to employees on the ground) can come closer to the line than permitted in paragraph (c)(3)(iii) of this
If any vehicle or mechanical equipment capable of having parts of its structure elevated
near energized overhead lines is intentionally grounded, employees working on the ground near the point of grounding may not stand at the grounding
location whenever there is a possibility of overhead line contact. Additional precautions, such as the use of barricades or insulation, shall be taken
to protect employees from hazardous ground potentials, depending on earth resistivity and fault currents, which can develop within the first few feet
or more outward from the grounding point.
Employees may not enter spaces containing exposed energized parts, unless illumination is
provided that enables the employees to perform the work safely.
Where lack of illumination or an obstruction precludes observation of the work to be performed,
employees may not perform tasks near exposed energized parts. Employees may not reach blindly into areas which may contain energized parts.
"Confined or enclosed work spaces." When an employee works in a confined or enclosed space (such as
a manhole or vault) that contains exposed energized parts, the employer shall provide, and the employee shall use, protective shields, protective
barriers, or insulating materials as necessary to avoid inadvertent contact with these parts. Doors, hinged panels, and the like shall be secured to
prevent their swinging into an employee and causing the employee to contact exposed energized parts.
"Conductive materials and equipment." Conductive materials and equipment that are in contact with
any part of an employee's body shall be handled in a manner that will prevent them from contacting exposed energized conductors or circuit parts. If
an employee must handle long dimensional conductive objects (such as ducts and pipes) in areas with exposed live parts, the employer shall institute
work practices (such as the use of insulation, guarding, and material handling techniques) which will minimize the hazard.
"Portable ladders." Portable ladders shall have nonconductive siderails if they are used where the
employee or the ladder could contact exposed energized parts.
"Conductive apparel." Conductive articles of jewelry and clothing (such a watch bands, bracelets,
rings, key chains, necklaces, metalized aprons, cloth with conductive thread, or metal headgear) may not be worn if they might contact exposed
energized parts. However, such articles may be worn if they are rendered nonconductive by covering, wrapping, or other insulating means.
"Housekeeping duties." Where live parts present an electrical contact hazard, employees may not
perform housekeeping duties at such close distances to the parts that there is a possibility of contact, unless adequate safeguards (such as
insulating equipment or barriers) are provided. Electrically conductive cleaning materials (including conductive solids 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.
"Interlocks." Only a qualified person following the requirements of paragraph (c) of this section
may defeat an electrical safety interlock, and then only temporarily while he or she is working on the equipment. The interlock system shall be
returned to its operable condition when this work is completed.
[55 FR 32016, Aug. 6, 1990; 55 FR 42053, Nov. 1, 1990; as amended at 59 FR 4476, Jan. 31, 1994]