Wash. Admin. Code § 296-24-95703 - General requirements
(1)
Approval. The conductors and equipment required or permitted by
this part is acceptable only if approved , as defined in WAC
296-24-990.
(2)
Examination, installation, and use
of equipment .
(a)
Examination. Electric equipment must be free from recognized
hazards that are likely to cause death or serious physical harm to employees.
You must determine the safety of equipment using the following considerations:
(i) Suitability for installation and use in
conformity with the provisions of this part;
(ii) Mechanical
strength and durability, including, for parts designed to enclose and protect
other equipment , the adequacy of the protection thus provided;
(iii) Wire-bending and connection
space;
(iv) Electrical
insulation;
(v) Heating effects
under all conditions of use;
(vi)
Arcing effects;
(vii)
Classification by type, size, voltage, current capacity, and specific use;
and
(viii) Other factors that
contribute to the practical safeguarding of persons using or likely to come in
contact with the equipment .
(b)Installation and use. You
must install and use listed or labeled equipment in accordance with any
instructions included in the listing or labeling.
(c)Insulation integrity.
Completed wiring installations must be free from short circuits and from
grounds other than those required or permitted by this part.
(d)
Interrupting rating.
Equipment intended to interrupt current at fault levels must have an
interrupting rating sufficient for the nominal circuit voltage and the current
that is available at the line terminals of the equipment . Equipment intended to
interrupt current at other than fault levels must have an interrupting rating
at nominal circuit voltage sufficient for the current that must be
interrupted.
(e)Circuit
impedance and other characteristics. You must select and coordinate the
overcurrent protective devices, the total impedance, the component
short-circuit current ratings, and other characteristics of the circuit to be
protected to permit the circuit protective devices used to clear a fault to do
so without the occurrence of extensive damage to the electrical components of
the circuit. You must assume this fault to be either between two or more of the
circuit conductors, or between any circuit conductor and the grounding
conductor or enclosing metal raceway .
(f)Deteriorating agents. Unless
identified for use in the operating environment, you must not locate any
conductors or equipment in damp or wet locations; where exposed to gases,
fumes, vapors, liquids, or other agents that have a deteriorating effect on the
conductors or equipment ; or where exposed to excessive temperatures.
(g)
Mechanical execution of
work. You must install electric equipment in a neat and workmanlike
manner.
(i) You must effectively close unused
openings in boxes, raceways, auxiliary gutters, cabinets, equipment cases, or
housings to afford protection substantially equivalent to the wall of the
equipment .
(ii) You must rack
conductors to provide ready and safe access in underground and subsurface
enclosures that persons enter for installation and maintenance.
(iii) Internal parts of electrical equipment ,
including busbars, wiring terminals, insulators, and other surfaces, may not be
damaged or contaminated by foreign materials such as paint, plaster, cleaners,
abrasives, or corrosive residues.
(iv) There must be no damaged parts that may
adversely affect safe operation or mechanical strength of the equipment , such
as parts that are broken, bent, cut, or deteriorated by corrosion, chemical
action, or overheating.
(h)
Mounting and cooling of
equipment .
(i) You must firmly secure
electric equipment to the surface on which it is mounted.
(ii) You must install electric equipment that
depends on the natural circulation of air and convection principles for cooling
of exposed surfaces so that room airflow over such surfaces is not prevented by
walls or by adjacent installed equipment . For equipment designed for floor
mounting, you must provide clearance between top surfaces and adjacent surfaces
to dissipate rising warm air.
(iii)
You must install electric equipment provided with ventilating openings so that
walls or other obstructions do not prevent the free circulation of air through
the equipment .
(3)
Electrical connections.
(a)General. Because of different
characteristics of dissimilar metals:
(i) You
must identify devices such as pressure terminal or pressure splicing connectors
and soldering lugs for the material of the conductor and you must properly
install and use them;
(ii)
Conductors of dissimilar metals may not be intermixed in a terminal or splicing
connector where physical contact occurs between dissimilar conductors (such as
copper and aluminum, copper and copper-clad aluminum, or aluminum and
copper-clad aluminum) unless the device is identified for the purpose and
conditions of use; and
(iii)
Materials such as solder, fluxes, inhibitors, and compounds, where employed,
must be suitable for the use and must be of a type that will not adversely
affect the conductors, installation, or equipment .
(b)Terminals.
(i) Connection of conductors to terminal
parts must ensure a good connection without damaging the conductors and must be
made by means of pressure connectors (including set-screw type), solder lugs,
or splices to flexible leads. However, No. 10 or smaller conductors may be
connected by means of wire binding screws or studs and nuts having upturned
lugs or equivalent.
(ii) You must
identify terminals for more than one conductor and terminals used to connect
aluminum as such.
(c)Splices.
(i) You must splice or join conductors with
splicing devices identified for the use or by brazing, welding, or soldering
with a fusible metal or alloy. You must first splice or join soldered splices
to be mechanically and electrically secure without solder and then soldered.
You must cover all splices and joints and the free ends of conductors with an
insulation equivalent to that of the conductors or with an insulating device
identified for the purpose.
(ii)
You must list wire connectors or splicing means installed on conductors for
direct burial for such use.
(4)Arcing parts. You must
enclose or separate and isolate parts of electric equipment that in ordinary
operation produce arcs, sparks, flames, or molten metal from all combustible
material.
(5)Marking.
(a)Identification of manufacturer and
ratings. Electric equipment may not be used unless the following
markings have been placed on the equipment :
(i) The manufacturer's name, trademark, or
other descriptive marking by which the organization responsible for the product
may be identified ; and
(ii) Other
markings giving voltage, current, wattage, or other ratings as
necessary.
(b)Durability. The marking must
be of sufficient durability to withstand the environment involved.
(6)
Disconnecting means and
circuits.
(a)Motors and
appliances . You must legibly mark each disconnecting means required by
this part for motors and appliances to indicate its purpose, unless located and
arranged so the purpose is evident.
(b)
Services, feeders, and branch
circuits. You must legibly mark each service , feeder , and branch
circuit , at its disconnecting means or overcurrent device , to indicate its
purpose, unless located and arranged so the purpose is evident.
(c)Durability of markings. The
markings required by this section must be of sufficient durability to withstand
the environment involved.
(d)Capable of accepting a lock.
Disconnecting means required by this part must be capable of being locked in
the open position.
(e)Marking
for series combination ratings.
(i)
Where circuit breakers or fuses are applied in compliance with the series
combination ratings marked on the equipment by the manufacturer, you must
legibly mark the equipment enclosures in the field to indicate that the
equipment has been applied with a series combination rating.
(ii) The marking required by (e)(i) of this
subsection must be readily visible and must state "Caution Series Combination
System Rated Amperes. Identified Replacement Component Required."
(7)600 Volts,
nominal, or less. This subsection applies to electric equipment
operating at 600 volts, nominal, or less to ground .
(a)
Space about electric
equipment . You must provide and maintain sufficient access and working
space about all electric equipment to permit ready and safe operation and
maintenance of such equipment .
(i) Working
space for equipment likely to require examination, adjustment, servicing, or
maintenance while energized must comply with the following dimensions, except
as required or permitted elsewhere in this part:
(A) The depth of the working space in the
direction of access to live parts may not be less than indicated in Table S-1.
You must measure distances from the live parts if they are exposed or from the
enclosure front or opening if they are enclosed ;
(B) The width of working space in front of
the electric equipment must be the width of the equipment or 30 inches,
whichever is greater. In all cases, the working space must permit at least a
90-degree opening of equipment doors or hinged panels; and
(ii) Working space required by this standard
may not be used for storage. When normally enclosed live parts are exposed for
inspection or servicing, you must suitably guard the working space, if in a
passageway or general open space.
(iii) You must provide at least one entrance
of sufficient area to give access to the working space about electric
equipment .
(iv) For equipment rated
1200 amperes or more and over 6 feet wide, containing overcurrent devices,
switching devices , or control devices, there must be one entrance not less than
24 inches wide and 6 feet 6 inches high at each end of the working space,
except that:
(A) Where the location permits a
continuous and unobstructed way of exit travel, one means of exit is permitted;
or
(B) Where the working space
required by (a)(i) of this subsection is doubled, only one entrance to the
working space is required; however, the entrance must be located so that the
edge of the entrance nearest the equipment is the minimum clear distance given
in Table S-1 away from such equipment .
(v) You must provide illumination for all
working spaces about service equipment , switchboards, panelboards, and motor
control centers installed indoors. Additional lighting fixtures are not
required where the working space is illuminated by an adjacent light source. In
electric equipment rooms, the illumination may not be controlled by automatic
means only.
(vi) The minimum
headroom of working spaces about service equipment , switchboards, panelboards,
or motor control centers must be as follows:
(A) For installations built before August 13,
2007, 6 feet 3 inches; and
(B) For
installations built on or after August 13, 2007, 6 feet 6 inches, except that
where the electrical equipment exceeds 6 feet 6 inches in height, the minimum
headroom may not be less than the height of the equipment .
Table S-1-Minimum Depth of Clear Working Space at
Electric
| Nominal |
Minimum clear distance for condition2, 3 | ||
| Condition A | Condition B | Condition C | |
| ft | ft | ft | |
| 0 - 150 | 13.0 | 13.0 | 3.0 |
| 151 - 600 | 13.01 | 3.5 | 4.0 |
Notes to Table S-1:
1 Minimum clear distances may be 2 feet 6 inches for installations built before April 16, 1981.
2 Conditions A, B, and C are as follows:
Condition A-
Condition B-
Condition C-
3 Working space is not required in
back of assemblies such as dead-front switchboards or motor control centers
where there are no renewable or adjustable parts (such as fuses or switches) on
the back and where all connections are
(vii) Switchboards, panelboards, and
distribution boards installed for the control of light and power circuits, and
motor control centers must be located in dedicated spaces and protected from
damage.
(A) For indoor installation, the
dedicated space must comply with the following:
(I) The space equal to the width and depth of
the equipment and extending from the floor to a height of 6 feet above the
equipment or to the structural ceiling, whichever is lower, must be dedicated
to the electrical installation. Unless isolated from equipment by height or
physical enclosures or covers that will afford adequate mechanical protection
from vehicular traffic or accidental contact by unauthorized personnel or that
complies with (a)(vii)(A)(II) of this subsection, piping, ducts, or equipment
foreign to the electrical installation may not be located in this
area;
(II) You must keep the space
equal to the width and depth of the equipment clear of foreign systems unless
protection is provided to avoid damage from condensation, leaks, or breaks in
such foreign systems. This area must extend from the top of the electric
equipment to the structural ceiling;
(III) Sprinkler protection is permitted for
the dedicated space where the piping complies with this section; and
(IV) Control equipment that by its very
nature or because of other requirements in this part must be adjacent to or
within sight of its operating machinery is permitted in the dedicated space.
(B) Outdoor electric equipment must be
installed in suitable enclosures and must be protected from accidental contact
by unauthorized personnel, or by vehicular traffic, or by accidental spillage
or leakage from piping systems. No architectural appurtenance or other
equipment may be located in the working space required by (a)(i) of this
subsection.
(b)
Guarding of live parts.
(i) Except as elsewhere required or permitted
by this standard, you must guard live parts of electric equipment operating at
50 volts or more against accidental contact by use of approved cabinets or
other forms of approved enclosures or by any of the following means:
(A) By location in a room, vault, or similar
enclosure that is accessible only to qualified persons;
(B) By suitable permanent, substantial
partitions or screens so arranged so that only qualified persons will have
access to the space within reach of the live parts. Any openings in such
partitions or screens must be so sized and located that persons are not likely
to come into accidental contact with the live parts or to bring conducting
objects into contact with them;
(C)
By placement on a suitable balcony, gallery, or platform so elevated and
otherwise located as to prevent access by unqualified persons; or
(D) By elevation of 8 feet or more above the
floor or other working surface.
(ii) In locations where electric equipment
would be exposed to physical damage, you must arrange enclosures or guards and
ensure that they are of such strength so as to prevent such damage.
(iii) You must mark entrances to rooms and
other guarded locations containing exposed live parts with conspicuous warning
signs forbidding unqualified persons to enter.
(8)
Over 600 volts, nominal .
(a)General. Conductors and
equipment used on circuits exceeding 600 volts, nominal, must comply with all
applicable provisions of subsections (1) through (7) of this section and with
the following provisions, which supplement or modify the preceding
requirements. However, (b) through (d) of this subsection do not apply to the
equipment on the supply side of the service point.
(b)
Enclosure for electrical
installations.
(i) Electrical
installations in a vault, room, or closet or in an area surrounded by a wall,
screen, or fence, access to which is controlled by lock and key or other
approved means, are considered to be accessible to qualified persons only. The
type of enclosure used in a given case must be designed and constructed
according to the hazards associated with the installation.
(ii) For installations other than equipment
described in (b)(v) of this subsection, you must use a wall, screen, or fence
to enclose an outdoor electrical installation to deter access by persons who
are not qualified . A wall, screen, or fence less than 8 feet in height is not
considered to prevent access unless it has other features that provide a degree
of isolation equivalent to an 8 foot fence.
(iii) The following requirements apply to
indoor installations that are accessible to other than qualified persons:
(A) You must make the installations with
metal-enclosed equipment or you must enclose them in a vault or in an area to
which access is controlled by a lock;
(B) You must mark metal-enclosed switchgear,
unit substations, transformers, pull boxes, connection boxes, and other similar
associated equipment with appropriate caution signs; and
(C) Openings in ventilated dry-type
transformers and similar openings in other equipment must be designed so that
foreign objects inserted through these openings will be deflected from
energized parts.
(iv)
Outdoor electrical installations having exposed live parts must be accessible
to qualified persons only.
(v) The
following requirements apply to outdoor enclosed equipment accessible to
unqualified employees:
(A) Ventilating or
similar openings in equipment must be so designed that foreign objects inserted
through these openings will be deflected from energized parts;
(B) Where exposed to physical damage from
vehicular traffic, you must provide suitable guards;
(C) Nonmetallic or metal-enclosed equipment
located outdoors and accessible to the general public must be designed so that
exposed nuts or bolts cannot be readily removed, permitting access to live
parts;
(D) Where nonmetallic or
metal-enclosed equipment is accessible to the general public and the bottom of
the enclosure is less than 8 feet above the floor or grade level, you must keep
the enclosure door or hinged cover locked; and
(E) Except for underground box covers that
weigh over 100 pounds, you must lock, bolt, or screw on doors and covers of
enclosures used solely as pull boxes, splice boxes, or junction
boxes.
(c)
Work space about equipment . You must provide and maintain
sufficient space about electric equipment to permit ready and safe operation
and maintenance of such equipment . Where energized parts are exposed , the
minimum clear work space may not be less than 6 feet 6 inches high (measured
vertically from the floor or platform) or less than 3 feet wide (measured
parallel to the equipment ). The depth must be as required in (e)(i) of this
subsection. In all cases, the work space must be adequate to permit at least a
90-degree opening of doors or hinged panels.
(d)Entrance and access to work
space.
(i) You must provide at least
one entrance not less than 24 inches wide and 6 feet 6 inches high to give
access to the working space about electric equipment .
(A) On switchboard and control panels
exceeding 6 feet in width, there must be one entrance at each end of such
boards unless the location of the switchboards and control panels permits a
continuous and unobstructed way of exit travel, or unless the work space
required in (e)(i) of this subsection is doubled.
(B) Where one entrance to the working space
is permitted under the conditions described in (d)(i)(A) of this subsection,
you must locate the entrance so that the edge of the entrance nearest the
switchboards and control panels is at least the minimum clear distance given in
Table S-2 away from such equipment .
(C) Where bare energized parts at any voltage
or insulated energized parts above 600 volts, nominal, to ground are located
adjacent to such entrance, you must suitably guard them.
(ii) You must provide permanent ladders or
stairways to give safe access to the working space around electric equipment
installed on platforms, balconies, mezzanine floors, or in attic or roof rooms
or spaces.
(e)
Working space and guarding.
(i)
Except as elsewhere required or permitted in this part, the minimum clear
working space in the direction of access to live parts of electric equipment
may not be less than specified in Table S-2. You must measure distances from
the live parts, if they are exposed , or from the enclosure front or opening, if
they are enclosed .
(ii) If
switches, cutouts, or other equipment operating at 600 volts, nominal, or less,
are installed in a room or enclosure where there are exposed live parts or
exposed wiring operating at over 600 volts, nominal , you must effectively
separate the high-voltage equipment from the space occupied by the low-voltage
equipment by a suitable partition, fence, or screen. However, switches or other
equipment operating at 600 volts, nominal, or less, and serving only equipment
within the high-voltage vault, room, or enclosure may be installed in the
high-voltage enclosure , room, or vault if accessible to qualified persons
only.
(iii) The following
requirements apply to the entrances to all buildings, rooms, or enclosures
containing exposed live parts or exposed conductors operating at over 600
volts, nominal :
(A) You must keep the
entrances locked unless they are under the observation of a qualified person at
all times; and
(B) You must provide
permanent and conspicuous warning signs, reading substantially as follows:
"DANGER-HIGH VOLTAGE-KEEP OUT."
(iv) You must provide illumination for all
working spaces about electric equipment .
(A)
You must arrange the lighting outlets so that persons changing lamps or making
repairs on the lighting system will not be endangered by live parts or other
equipment .
(B) You must locate the
points of control so that persons are prevented from contacting any live part
or moving part of the equipment while turning on the lights.
(v) You must maintain unguarded
live parts above working space at elevations not less than specified in Table
S-3.
(vi) Pipes or ducts that are
foreign to the electrical installation and that require periodic maintenance or
whose malfunction would endanger the operation of the electrical system may not
be located in the vicinity of service equipment , metal-enclosed power
switchgear, or industrial control assemblies. You must provide protection where
necessary to avoid damage from condensation leaks and breaks in such foreign
systems.
Table S-2-Minimum Depth of Clear Working Space at
Electric
| Nominal |
Minimum clear distance for condition2, 3 | ||
| Condition A | Condition B | Condition C | |
| ft | ft | ft | |
| 601-2500 V | 3.0 | 4.0 | 5.0 |
| 2501-9000 V | 4.0 | 5.0 | 6.0 |
| 9001 V-25 kV | 5.0 | 6.0 | 9.0 |
| Over 25-75 kV1 | 6.0 | 8.0 | 10.0 |
| Above 75 kV1 | 8.0 | 10.0 | 12.0 |
Notes to Table S-2:
1 Minimum depth of clear working
space in front of electric
2 Conditions A, B, and C are as follows:
Condition A-
Condition B-
Condition C-
3 Working space is not required in
back of
Table S-3-Elevation of Unguarded Live Parts Above Working Space
| Nominal voltage between phases | Elevation |
| ft | |
| 601-7500 V | 19.0 |
| 7501 V-35 kV | 9.0 |
| Over 35 kV | 9.0 + 0.37 in/kV over 35 kV |
1 The minimum elevation may be 8 feet 6 inches for installations built before August 13, 2007. The minimum elevation may be 8 feet for installations built before April 16, 1981, if the nominal voltage between phases is in the range of 601-6600 volts.
Notes
Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060, and chapter 49.17 RCW. 12-16-064, § 296-24-95703, filed 7/31/12, effective 9/1/12.
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