This section applies to work on exposed live parts, or near
enough to them, to expose the employee to any hazard they present.
(1) General. Only qualified electrical
employees may work on or with exposed energized lines or parts of equipment.
Only qualified electrical employees may work in areas containing unguarded,
uninsulated energized lines or parts of equipment operating at 50 volts or
more. Electric lines and equipment must be considered and treated as energized
unless the provisions of WAC
296-45-175
through
296-45-17565
or
296-45-335
have been followed.
(2) Except as
provided in subsection (3) of this section, at least two qualified electrical
employees must be present while the following types of work are being
performed:
(a) Installation, removal, or
repair of lines that are energized at more than 600 volts;
(b) Installation, removal, or repair of
deenergized lines if an employee is exposed to contact with other parts
energized at more than 600 volts;
(c) Installation, removal, or repair of
equipment, such as transformers, capacitors, and regulators, if an employee is
exposed to contact with parts energized at more than 600 volts;
(d) Work involving the use of mechanical
equipment, other than insulated aerial lifts, near parts energized at more than
600 volts; and
(e) Other work that
exposes an employee to electrical hazards greater than or equal to those posed
by operations that are specifically listed in subsection (2)(a) through (d) of
this section.
|
Notes:
|
*One qualified electrical employee will serve
principally as a standby person who must be so located that they may physically
reach the other qualified electrical employee in the event of an accident
either with their hand or with a hot stick twelve feet or less in length. The
standby person will be so positioned as to be able to observe the other
employee, their bodily movements, and verbally warn of any impending dangers.
In no case when working in pairs will qualified electrical employees work
simultaneously on energized wires or parts of different phases or
polarity;
*When installing or removing a hot line clamp
connection on a multiphase system, it is permissible for the second qualified
electrical employee to stand by at the lower controls of the aerial lift
provided the connection or disconnection does not interrupt or pick up the
load. The hot line clamp and connecting jumper must be constructed so it cannot
make contact with any other energized parts. The work must not be performed
above lines or apparatus energized at more than 600 V.
*In cases of necessity the standby person may
temporarily assist the other qualified electrical employee provided that they
both work on wires or parts of the same phase or polarity. Both qualified
electrical employees must so position themselves so that the presence of the
second person does not increase the hazard.
|
(3) The provisions of WAC
296-45-325(2) do
not apply to (a) through (e) of this subsection. In addition to the
requirements of subsection (4) of this section, a qualified electrical employee
working under this subsection (3), must position themselves so that they are
neither within reach of nor otherwise exposed to contact with energized parts.
(a) When re-fusing circuits or equipment with
a hot stick.
(b) When operating
switches by means of operating handle or switch sticks.
(c) When installing or removing a hot line
clamp connection with an approved hot stick on a single-phase line or
apparatus, providing that the connection or disconnection does not interrupt or
pick up a load.
| Notes: |
* The hot line clamp and connecting jumper must be
constructed so that it cannot make contact with any other energized parts.
|
| * On a multiphase feed this applies only when one
single-phase line or apparatus is present on the load side. |
(d)
When installing or removing by hot stick simple load metering devices provided
the connection does not interrupt or pickup load.
(e) Emergency repairs to the extent necessary
to safeguard the general public.
(4) Minimum approach distances. The employer
must ensure that no employee approaches or takes any conductive object closer
to exposed energized parts than set forth in Table 2, unless:
(a) The employee is insulated from the
energized part (insulating gloves or insulating gloves and sleeves worn in
accordance with subsection (6) of this section are considered insulation of the
employee only with regard to the energized part upon which work is being
performed); or
(b) The energized
part is insulated from the employee and from any other conductive object at a
different potential;
(c) Appendix A
of this chapter contains additional information relating to working on exposed
energized parts.
(d) For voltages
over 72.5 kilovolts, the employer must determine the maximum anticipated
per-unit transient over-voltage, phase-to-ground, through an engineering
analysis or assume a maximum anticipated per-unit transient overvoltage,
phase-to-ground, in accordance with Table 4 of this section. When the employer
uses portable protective gaps to control the maximum transient overvoltage, the
value of the maximum anticipated per-unit transient overvoltage,
phase-to-ground, must provide for five standard deviations between the
statistical spark-over voltage of the gap and the statistical withstand voltage
corresponding to the electrical component of the minimum approach distance. The
employer must make any engineering analysis conducted to determine maximum
anticipated per-unit transient overvoltage available upon request to employees
and to the department for examination and copying.
Table 2
AC Live Work Minimum Approach Distance
|
Distance to Employee
|
|
Voltage in Kilovolts Phase-to-Phase
|
Phase-to-Ground
|
Phase-to-Phase
|
|
(ft-in)
|
(ft-1/10)
|
(m)
|
(ft-in)
|
(ft-1/10)
|
(m)
|
|
Table 2-A For Voltages of 72.5 KV and Less
(1, 2, 3, 4)
|
|
|
| 0 to 0.050 |
not specified |
not specified |
| 0.051 to 0.300 |
avoid contact |
avoid contact |
| 0.301 to 0.750 |
1'-2" |
1.09 |
0.33 |
1'-2" |
1.09 |
0.33 |
| 0.751 to 5 |
2'-1" |
2.07 |
0.63 |
2'-1" |
2.07 |
0.63 |
| 5.1 to 15.0 |
2'-2" |
2.14 |
0.65 |
2'-3" |
2.24 |
0.68 |
| 15.1 to 36.0 |
2'-7" |
2.53 |
0.77 |
3'-0" |
2.92 |
0.89 |
| 36.1 to 46.0 |
2'-10" |
2.76 |
0.84 |
3'-3" |
3.22 |
0.98 |
| 46.1 to 72.5 |
3'-3" |
3.29 |
1.00 |
4'-0" |
3.94 |
1.20 |
|
1Employers may use the minimum
approach distances in this table provided the worksite is at an elevation of 3,
000 feet (900 meters) or less. If employees will be working at elevations
greater than 3, 000 feet (900 meters) above mean sea level, the employer must
determine minimum approach distances by multiplying the distances in this table
by the correction factor in Table 3 below, altitude correction factors. |
|
2For single-phase systems, use
voltage-to-ground. |
|
3For single-phase lines off three
phase systems, use the phase-to-phase voltage of the system. |
|
4The 46.1 to 72.5 kV
phase-to-ground 3-3 distance contains a 1-3 electrical component and a 2'-0
inadvertent movement component. |
|
Table 2-B For Voltages of 72.6 KV
and
up 5, 6, 7)
|
Phase-to-Ground
|
Phase-to-Phase
|
|
(ft-in)
|
(ft-1/10)
|
(m)
|
(ft-in)
|
(ft-1/10)
|
(m)
|
| 72.6 to 121 |
3'-9"** |
3.71** |
1.13 |
4'-8" |
4.66 |
1.42 |
| 121.1 to 145.0 |
4'-4" |
4.27 |
1.30 |
5'-5" |
5.38 |
1.64 |
| 145.1 to 169.0 |
4'-10" |
4.79 |
1.46 |
6'-5" |
6.36 |
1.94 |
| 169.1 to 242.0 |
6'-8" |
6.59 |
2.01 |
10'-2" |
10.10 |
3.08 |
| 242.1 to 362.0 |
11'-3" |
11.19 |
3.41 |
18'-2" |
18.11 |
5.52 |
| 362.1 to 420.0 |
14'-0" |
13.94 |
4.25 |
22'-5" |
22.34 |
6.81 |
| 420.1 to 550.0 |
16'-8" |
16.63 |
5.07 |
27'-1" |
27.03 |
8.24 |
| 550.1 to 800.0 |
22'-7" |
22.57 |
6.88 |
37'-5" |
37.34 |
11.38 |
|
5Employers may use the minimum
approach distances in this table provided the worksite is at an elevation of 3,
000 feet (900 meters) or less. If employees will be working at elevations
greater than 3, 000 feet (900 meters) above mean sea level, the employer shall
determine minimum approach distances by multiplying the distances in this table
by the correction factor in Table 3 below, altitude corrections factor. |
|
6Employers may use the
phase-to-phase minimum approach distances in this table provided that no
insulated tool spans the gap and no large conductive object is in the gap. (See
Equation 1 for voltages of 72.6-800 kV in Appendix A.) |
|
7The 72.6 to 121 kV
phase-to-ground 3-9 distance contains a 2-9 electrical component and a 1'-0
inadvertent movement component.** |
|
Note: The clear live-line tool
distance shall equal or exceed the values for the indicated voltage
ranges.
|
Table 3 - Altitude Correction Factors
Altitude above sea level (m)
|
A
|
| 0 to 900 .......................... |
1.00 |
| 901 to 1, 200 ....................... |
1.02 |
| 1, 201 to 1, 500 ..................... |
1.05 |
| 1, 501 to 1, 800 ..................... |
1.08 |
| 1, 801 to 2, 100 ..................... |
1.11 |
| 2, 101 to 2, 400 ..................... |
1.14 |
| 2, 401 to 2, 700 ..................... |
1.17 |
| 2, 701 to 3, 000 ..................... |
1.20 |
| 3, 001 to 3, 600 ..................... |
1.25 |
| 3, 601 to 4, 200 ..................... |
1.30 |
| 4, 201 to 4, 800 ..................... |
1.35 |
| 4, 801 to 5, 400 ..................... |
1.39 |
| 5, 401 to 6, 000 ..................... |
1.44 |
Table 4 Assumed Maximum Per-Unit Transient
Overvoltage
|
Voltage Range (kV)
|
Type of Current (ac or dc)
|
Assumed Maximum Per-Unit Transient
Over-voltage
|
| 72.6 to 420.0 |
ac |
3.5 |
| 420.1 to 550.0 |
ac |
3.0 |
| 550.1 to 800.0 |
ac |
2.5 |
| 250 to 750 |
dc |
1.8 |
|
Notes:
|
*WAC
296-45-475(5)(a)
and
296-45-48525(1)
contain requirements for the guarding and isolation of live parts. Parts of
electric circuits that meet these two provisions are not considered as
"exposed" unless a guard is removed or an employee enters the space intended to
provide isolation from the live parts.
*When an employee is required to work on or within
reach of any unprotected conductors that are or may become energized at more
than 50 volts and less than 600 volts between phases, they shall take the
following precautions:
-They shall wear approved insulating gloves or
insulating gloves and sleeves during the time they are working on such
conductor; or
-They shall cover, with approved devices, any adjacent
unprotected conductor that could be touched by any part of their body, and use
insulated tools.
-Cables which are properly insulated for the voltages
to which they are energized, shall be considered as an effective barrier to
protect the employees and Table 2 need not apply.
*Appendix A of this chapter contains additional
information relating to working on exposed energized parts.
|
(5) Initial determination.
(a) Before any work is performed, the
location of energized lines and their condition, the location and condition of
energized equipment, the condition of the poles, the location of circuits and
equipment including power communication lines, CATV and fire alarm circuits,
must be determined and communicated to employees as will any other particular
hazard of a particular work site.
(b) No work must be performed on energized
lines or parts until the voltage of such equipment and lines is
determined.
(6) Type of
insulation. If the employee is to be insulated from energized parts by the use
of insulating gloves (under subsection (4) of this section), insulating sleeves
must also be used. However, insulating sleeves need not be used under the
following conditions:
(a) If exposed
energized parts on which work is not being performed are insulated from the
employee; and
(b) If such
insulation is placed from a position not exposing the employee's upper arm to
contact with other energized parts.
(7) Working position. The employer must
ensure that each employee, to the extent that other safety-related conditions
at the worksite permit, works in a position from which a slip or shock will not
bring the employee's body into contact with exposed, uninsulated parts
energized at a potential different from the employee.
(8) Making connections. The employer must
ensure that connections are made as follows:
(a) In connecting deenergized equipment or
lines to an energized circuit by means of a conducting wire or device, an
employee must first attach the wire to the deener-gized part;
(b) When disconnecting equipment or lines
from an energized circuit by means of a conducting wire or device, an employee
must remove the source end first; and
(c) When lines or equipment are connected to
or disconnected from energized circuits, loose conductors must be kept away
from exposed energized parts.
(9) Rubber gloves can only be used on 5, 000
volts or less between phases.
(10)
It must not be permissible to consider one part of a high voltage switch or
disconnect as deenergized for the purpose of doing work on it if the remainder
of the switch or disconnect remains energized unless approved barriers are
erected which will prevent employees who are doing the work on such equipment
from coming in direct contact with the energized parts.
(11) Conductor support tools such as link
sticks, strain carriers, and insulator cradles may be used: Provided, That the
clear insulation is at least as long as the insulator string or the minimum
distance specified in Table 2 for the operating voltage.
(12) Apparel.
(a) When work is performed within reaching
distance of exposed energized parts of equipment, the employer must ensure that
each employee removes or renders noncon-ductive all exposed conductive
articles, such as key or watch chains, rings, or wrist watches or bands, unless
such articles do not increase the hazards associated with contact with the
energized parts.
(b) Employees must
wear clothing appropriate to the season and the kind of work being performed.
Shirts or jumpers must have full length sleeves that are rolled down.
Protective hard hats and eye protection must be worn when working on or near
live parts or while climbing poles.
(13) Protection from flames and electric
arcs.
(a) The employer must assess the
workplace to identify employees exposed to hazards from flames or from electric
arcs.
(b) For each employee exposed
to hazards from electric arcs, the employer must make a reasonable estimate of
the incident heat energy to which the employee would be exposed.
|
Notes:
|
*Appendix D of this chapter provides guidance on
estimating available heat energy. The department will deem employers following
the guidance in Appendix D to be in compliance with (b) of this subsection. An
employer may choose a method of calculating incident heat energy not included
in Appendix D if the chosen method reasonably predicts the incident energy to
which the employee would be exposed.
*This subsection does not require the employer to
estimate the incident heat energy exposure for every job task performed by each
employee. The employer may make broad estimates that cover multiple system
areas provided the employer uses reasonable assumptions about the
energy-exposure distribution throughout the system and provided the estimates
represent the maximum employee exposure for those areas. For example, the
employer could estimate the heat energy just outside a substation feeding a
radial distribution system and use that estimate for all jobs performed on that
radial system.
|
(c)
The employer must ensure that each employee who is exposed to hazards from
flames or electric arcs does not wear clothing that could melt onto their skin
or that could ignite and continue to burn when exposed to flames or the heat
energy estimated under (b) of this subsection.
| Note: |
This subsection prohibits clothing made from acetate,
nylon, polyester, rayon and polypropylene, either alone or in blends, unless
the employer demonstrates that the fabric has been treated to withstand the
conditions that may be encountered by the employee or that the employee wears
the clothing in such a manner as to eliminate the hazard involved. |
(d)
The employer must ensure that the outer layer of clothing worn by an employee,
except for clothing not required to be arc rated under (e)(i) through (v) of
this subsection, is flame resistant under any of the following conditions:
(i) The employee is exposed to contact with
energized circuit parts operating at more than 600 volts;
(ii) An electric arc could ignite flammable
material in the work area that, in turn, could ignite the employee's
clothing;
(iii) Molten metal or
electric arcs from faulted conductors in the work area could ignite the
employee's clothing; or
| Note: |
This subsection does not apply to conductors that are
capable of carrying, without failure, the maximum available fault current for
the time the circuit protective devices take to interrupt the fault. |
(iv)
The incident heat energy estimated under (b) of this subsection exceeds 2.0
cal/cm2.
(e) The employer must ensure that each
employee exposed to hazards from electric arcs wears protective clothing and
other protective equipment with an arc rating greater than or equal to the heat
energy estimated under (b) of this subsection whenever that estimate exceeds
2.0 cal/cm
2. This protective equipment must cover
the employee's entire body, except as follows:
(i) Arc-rated protection is not necessary for
the employee's hands when the employee is wearing rubber insulating gloves with
protectors or, if the estimated incident energy is no more than 14
cal/cm2, heavy-duty leather work gloves with a
weight of at least 407 gm/m2(12
oz/yd2);
(ii) Arc-rated protection is not necessary
for the employee's feet when the employee is wearing heavy-duty work shoes or
boots;
(iii) Arc-rated protection
is not necessary for the employee's head when the employee is wearing head
protection meeting WAC
296-800-16055
if the estimated incident energy is less than 9
cal/cm
2 for exposures involving single-phase arcs in
open air or 5 cal/cm
2 for other exposures;
(iv) The protection for the employee's head
may consist of head protection meeting WAC
296-800-16055
and a face-shield with a minimum arc rating of 8
cal/cm
2 if the estimated incident-energy exposure is
less than 13 cal/cm
2 for exposures involving
single-phase arcs in open air or 9 cal/cm
2 for other
exposures; and
(v) For exposures
involving singlephase arcs in open air, the arc rating for the employee's head
and face protection may be 4 cal/cm
2 less than the
estimated incident energy.
| Note: |
See Appendix D of this chapter for further information on
the selection of appropriate protection. |
(14) Fuse handling. When fuses must be
installed or removed with one or both terminals energized at more than 300
volts or with exposed parts energized at more than 50 volts, the employer must
ensure that tools or gloves rated for the voltage are used. When expulsion-type
fuses are installed with one or both terminals energized at more than 300
volts, the employer must ensure that each employee wears eye protection meeting
the requirements of WAC
296-45-25505(1),
uses a tool rated for the voltage, and is clear of the exhaust path of the fuse
barrel.
(15) Covered (noninsulated)
conductors. The requirements of this section which pertain to the hazards of
exposed live parts also apply when work is performed in the proximity of
covered (noninsulated) wires.
(16)
Noncurrent-carrying metal parts. Noncurrent-carry-ing metal parts of equipment
or devices, such as transformer cases and circuit breaker housings, must be
treated as energized at the highest voltage to which they are exposed, unless
the employer inspects the installation and determines that these parts are
grounded before work is performed.
(17) Opening circuits under load. Devices
used to open circuits under load conditions must be designed to interrupt the
current involved.
