3/21/2014
Addressing
Arc Flash Hazards
Without
Breaking the Bank
Safety Day 2014
Waubonsee Community College
Addressing Arc Flash Hazards
Without Breaking the Bank - Module No. 3
Live electrical work
should be done using
insulated tools
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This presentation is based on
OSHA 29 CFR 1910 Subpart S legal requirements for
facility electrical systems and work practices including
but not limited to:
29 CFR1910.332
Training
29 CFR1910.333
Selection and use of
work practices
29 CFR1910.334
Use of equipment
29 CFR1910.335
Safeguards for
personnel protection
In addition the program references NFPA 70E
“Standard for Electrical Safety in the Workplace”,
2009 Edition
Arc Flash/Blast for Qualified Persons
An arc flash/blast occurs when
current flows between two
conductors through air, e.g.:
– Tool slips and makes
contact with
conductors energized
at different potential
– Insulation fails
Arc flash
• The flash may be 35,000 °F
• Three inches of # 10 copper may vaporize to 1 ft³
in volume
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Arc Flash/Blast for Qualified Persons
Arc energy released is
determined by
• Voltage
• Arc resistance
• Available shortcircuit current, and
• Time needed for
overcurrent device
to open
Vapors released by the arc are conductive and
sustain the arc through its duration
Heat energy absorbed by persons or objects in the area are
stated as calories of heat energy per square centimeter
or cal/cm2
Arc Flash for Qualified Persons
Arc flash results
• Death
• Serious injuries
– Burning – even
vaporizing the skin
– Blindness and other
damage to the eyes
– Deafness
– Internal injuries
Flash burns – arc
flash incident
• Disastrous fires
• Damage and destruction of equipment
• Extensive downtime
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Arc Flash for Qualified Persons
Severe burns or death
may be caused by
• Clothing that ignites
instantly
• Continues to burn
long after the arc has
subsided
• Enclosed spaces and
panel doors that don’t
open fully increase the
danger
Proper PPE is essential
Employees’ hands and faces are often 6 – 12
inches from the arc
Arc Flash for Qualified Persons
The fabrics or materials of arc flash PPE
are tested and rated for resistance to arc flash
energy
Rating reflects the maximum
heat energy resistance of a
material during an incident
• Prior to “breakopen”
(formation of openings or
holes) from heating or
• At the onset a seconddegree skin burn.
Arc rating label identifies this
level and lists it in cal/cm2
COMPLIANCE TO
ASTM 1506
NFPA 70E
OSHA 1910.335
ARC RATING 4 CAL/CM2
Size 16 - 33
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Arc Blast for Qualified Persons
Single phase-to-phase
fault on a 480V
system with 20,000
amps of available fault
current
• Releases energy
equivalent to
1.5 pounds of TNT
• Resulting
devastation is
comparable.
• Arcs often cause
serious injuries or
death
Arc Blast for Qualified Persons
Arc blast results
• 140 Decibel sound pressure may rupture
eardrums
• Air pressure > 2000 psf
• Forces on the
chest may be
1000 lbs
– Puncture the
lungs
– Break bones
• Whiplash
resulting in
brain damage
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Arc Blast for Qualified Persons
Exposure to arc flash
without protection by
– Distance
– Safety procedures
– Protective equipment
The solution in most cases
is to work with or around
electrical circuits that are
• guarded or
• de-energized, locked and
tagged out
Arc Blast for Qualified Persons
Work on or around
energized electrical circuits
or equipment is permitted
only
– At less than 50 volts
– Not feasible, e.g.:
• Electrical testing
(checking for voltage)
• Trouble shooting
– Where there is a greater
hazard, e.g.: immediately
necessary to save a life
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Arc Flash/Blast for Qualified Persons
Some reported incident causes
• Accidental contact with energized parts
• Tools dropped on energized parts
• Improper work procedures
• Tracking across insulation surfaces
• Mechanical breakdown, loose connections,
and insulation failure
• Corrosion of equipment parts
and contacts
• Contamination, such as dust
on insulating surfaces
• Wiring errors
• Inadequate short circuit ratings
Arc Blast for Qualified Persons
What should
we do?
Comply with
OSHA legal
mandates for
plant electrical
• Equipment and
installations
• Electrical safetyrelated work
practices
This also requires
• Electrical safety program
and procedures
• Recognized and respected
approach limits for
exposed energized parts
and circuits
• Hazard/Risk category
classifications
• Appropriate personal
protective equipment
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Electrical Safety Program
The employer should develop a
written electrical safety
program based on NFPA 70E
Activities must be based on
– Voltages involved
– Determination and
understanding of energy
levels
– Identification of the
condition of circuits
NFPA 70E Article 110.7
and the NFPA 70E
Handbook give the details
Arc Flash/Blast for Qualified Persons
• Regular
maintenance
inspection can
identify many
potential arc
flash issues
• Checking for
heating of system
components and
wiring is important
• If available,
infrared
photography may
be very useful
In-use equipment
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Module 3 Unit 3 - 1
Arc Flash/Blast for Qualified Persons
Practice Quiz
1. An arc flash/blast occurs when current flows between two
conductors through ___________.
A. Water
B. An electrician
C. Ground
D. Air
2. The temperature at the terminals in an arc flash/blast can be
as high as ___________.
A. The surface of the sun
B. 18,000 °F
C. Almost hot enough to melt copper
D. As high as 35,000 °F
Module 3 Unit 3 - 1
Arc Flash/Blast for Qualified Persons
Practice Quiz
1. An arc flash/blast occurs when current flows between two
conductors through ___________.
A. Water
B. An electrician
C. Ground
D. Air
2. The temperature at the terminals in an arc flash/blast can be
as high as ___________.
A. The surface of the sun
B. 18,000 °F
C. Almost hot enough to melt copper
D. As high as 35,000 °F
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Module 3 Unit 3 - 1
Arc Flash/Blast for Qualified Persons
Practice Quiz
3. The expansion of copper in an arc flash/blast is equivalent to
three inches of # 10 copper vaporizing to _________.
A. 1 cubic foot in volume
B. 1 cubic inch in volume
C. 1 cubic yard in volume
D. Enough to fill a small room
4. Heat energy absorbed by persons or objects in the area are
stated as ___________.
A. Joules of heat energy per cubic meter
B. Calories of heat energy per pound of body weight
C. Calories of heat energy per square centimeter
D. Perspiration threshold
Module 3 Unit 3 - 1 Arc Flash/Blast for Qualified Persons
Practice Quiz
3. The expansion of copper in an arc flash/blast is equivalent to
three inches of # 10 copper vaporizing to _________.
A. 1 cubic foot in volume
B. 1 cubic inch in volume
C. 1 cubic yard in volume
D. Enough to fill a small room
4. Heat energy absorbed by persons or objects in the area are
stated as ___________.
A. Joules of heat energy per cubic meter
B. Calories of heat energy per pound of body weight
C. Calories of heat energy per square
centimeter
D. Perspiration threshold
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Module 3 Unit 3 - 1
Arc Flash/Blast for Qualified Persons
Practice Quiz
5. The employer should develop a written electrical safety
program with activities based on __________________.
A. Voltages, energy levels and condition of circuits
B. Test results, insulated means and oversight
C. Production schedules
D. All of the above
Module 3 Unit 3 - 1
Arc Flash/Blast for Qualified Persons
Practice Quiz
5. The employer should develop a written electrical safety
program with activities based on __________________.
A. Voltages, energy levels and condition
of circuits
B. Test results, insulated means and oversight
C. Production schedules
D. All of the above
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Keys to Understanding
NFPA 70E
Keys to Understanding NFPA 70E –
In this unit, we will describe and explain several
terms useful in understanding NFPA 70E . These
concepts will help in preventing electrical accidents
and help in implementing a successful electrical
safety program. These key terms are:
–Limits of Approach
and Boundaries
–Hazard/Risk
Categories
–Arc Ratings
–Personal Protective
Equipment and
Clothing
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Keys to understanding NFPA 70E
Preventing electrical accidents and
implementing a successful
electrical safety program involves
– Compliance with OSHA’s legal
electrical work practices
requirements
– Implementing and following a
proven effective safety guidance
like NFPA 70E, Standard for
Electrical Safety in the Workplace
2009
– NFPA 70E is nationally recognized
as an appropriate guidance
Keys to understanding NFPA 70E
Limits of Approach and Boundaries
Safe approach distances from exposed energized
electrical conductors or circuit parts. They are
described and categorized in NFPA 70E and are
based on the level of electrical arc flash and shock
hazard.
Hazard/Risk Categories
A rating system for the
relative electrical hazard
of tasks
Arc Ratings
Values identify the level of
performance of PPE in an
electrical arc discharge
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Limits of Approach and Boundaries
• Arc flash boundaries are
determined by arc flash energy
(incident energy) available to
contact the employee(s)
• Incident energy is measured in
calories per square centimeter
(cal/cm2). It is determined by:
– System Voltage
– Available short-circuit current
– Time needed for overcurrent
device to open
Flash Protection Boundary
Boundary within which an unprotected person would
receive at least a 2nd degree burn from an arc flash –
“blister boundary”
Default distance of 4 foot minimum for equipment up
to 600 V (provided system capacity does not exceed
100 kA cycles)
– Increased for higher voltages
– Crossing this boundary
requires wearing
appropriate PPE
– Qualified persons only
– Unqualified must be
Default
accompanied
Flash
NFPA 70E – Article 100, 130.3 (A) (1)
Protection
Boundary
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Default Flash Protection Boundary
Minimum 4 foot flash
protection boundary is
based on
– Bolted fault current of 50 kA
– Clearing time of 2 cycles
(0.033 sec.) and
– Other general equipment
information
Utility power supply
provides higher incident
energy at the plant service
entrance
See NFPA 70E Article 130.3 (A) (1)
Don’t work inside or on
this energized utility
supply switchgear panel
Shock Approach Boundaries to
Energized Electrical Conductors
For exposed energized conductors and parts
• Shock Protection Boundaries include the
following boundaries for the given task:
– Limited
– Restricted
– Prohibited
SHOCK HAZARD
• Options for determining the location of shock
approach boundaries include:
– Detailed analysis and calculations
– Distances identified for various voltages as
shown in NFPA 70E Table 130.2(C)
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Excerpt - Table 130.2(C) Approach Boundaries For Shock Protection
Distance from energized conductor or part to employee
Limited Approach Boundary1
Nominal System,
Voltage Range,
Phase to Phase2
Exposed Movable
Conductor3
Exposed Fixed
Circuit Part
Restricted
Approach
Boundary1;
Prohibited
Approach
Boundary1
Includes
Inadvertent
Movement
Adder
Less than 50
Not specified
Not specified
Not specified
50 to 300
10 ft 0 in.
3 ft 6 in.
Avoid contact
Avoid contact
301 to 750
10 ft 0 in.
3 ft 6 in.
1 ft 0 in.
0 ft 1 in.
50 to 300 volts
Not specified
301 to 750 volts
– 3 for
feet
6 regarding
inches
Limited – 3 feet
See the6complete
inches
Table 130.2 inLimited
NFPA 70E 2009
details
voltage higher than 750 volts Restricted – 1 foot
Restricted – Avoid Contact
Prohibited – 1 inch or more
Prohibited – Avoid Contact
Note: For Arc Flash Protection Boundary, see 130.3(A).
751 to 15 kV
1 See definition in Article 100 and text in 130.2(D)(2) and Annex C for elaboration.
2 For single-phase systems, select the range that is equal to the system’s maximum phase-to-ground voltage
multiplied by 1.732.
3 A condition in which the distance between the conductor and a person is not under the control of the
person. The term is normally applied to overhead line conductors supported by poles.
Provide as Handout
Approach Boundaries for Shock Protection –
Table 130.2 (C)
50 to 300 volts
Limited – 3 feet 6 inches
Restricted – Avoid Contact
Prohibited – Avoid Contact
301 to 750 volts
Limited – 3 feet 6 inches
Restricted – 1 foot
Prohibited – 1 inch or more
Limited
Restricted
Prohibited
Shock
Approach
Boundaries
Fixed Parts
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Prohibited
approach
boundary
Any point on an
exposed
energized
conductor
Prohibited
space
Restricted
approach
boundary
Restricted
space
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Limited
approach
boundary
Limited
space
Flash
Exposure
Area
Flash
Protection
Boundary
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Approach Boundaries
Arc flash
protection
boundary
Limited
approach
boundary
Prohibited Space
Restricted
space
Restricted
approach
boundary
Limited Approach Boundary
Work inside the limited
approach boundary
is for QPs only
For most exposed
energized 480 VAC
parts = 3 feet 6 inches
Unqualified persons must be
– Accompanied by a QP
– Advised of risk of shock and
electrocution
– Advised of the location of the exposed
energized conductors NFPA 70E Article 130.2 (D) (1), (2)
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Limited Approach Boundary
Unqualified persons –
Management, supervisors
and QPs must ensure
safety e.g.:
– Barriers
– Warnings
– Signs or barricades
– The person must be
informed and know of
how to avoid the
hazards
NFPA 70E Article 130.2 (D) (1), (2)
Unqualified persons are
Not qualified for
never permitted within the
electrical
Task
restricted approach
boundary
Restricted Approach Boundary
Crossed only by
qualified person
Requires shock
protection
techniques and
equipment
– Properly rated PPE
– Training
– Documented work
plan approved by
management
Prohibited Space
QP must keep all uninsulated parts of body out of
“Prohibited Space”
NFPA 70E Article 130.2 (C) (1), (2)
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Prohibited Approach Boundary
• Crossed only by
qualified person
• Requires same
protection as if
making contact with
live parts
• To cross into
“Prohibited Space”
must have specific
training
• Documented plan
justifying need to
perform this work
NFPA 70E Article 130.1 (B)
Prohibited Approach Boundary
Working within the prohibited
approach boundary around
energized electrical equipment
–Requires an “Energized
Electrical Work Permit”
–Considered the same as
making contact with the
energized parts
–Only 1 inch from 480 volt
parts
–Too close for comfort without
safety precautions and
protection
NFPA 70E Article 130.1 (B)
Energized
Work Permit
Task
Reason for
Live Work
Precautions
PPE
Management
Signature
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Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
1. The flash protection boundary is defined as ____________.
A. The distance required for the flash to operate properly on
an infrared thermography camera
B. The boundary within which an unprotected person would
receive at least 2nd degree burns
C. The boundary within which an electrician can work without
fear of arc flash
D. The boundary within which live work is approved
2. Crossing the flash protection boundary requires __________.
A. Rayon undergarments
B. Steel-toed shoes
C. At a minimum, sunglasses to protect the eyes
D. Appropriate PPE to protect against arc flash/blast and
shock
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
1. The flash protection boundary is defined as ____________.
A. The distance required for the flash to operate properly on
an infrared thermography camera
B. The boundary within which an unprotected person
would receive at least 2nd degree burns
C. The boundary within which an electrician can work without
fear of arc flash
D. The boundary within which live work is approved
2. Crossing the flash protection boundary requires __________.
A. Rayon undergarments
B. Steel-toed shoes
C. At a minimum, sunglasses to protect the eyes
D. Appropriate PPE to protect against arc
flash/blast and shock
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Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
3. The default distance for the flash protection boundary is
__________ for equipment up to 600 V.
A. Two feet
B. No further than the restricted approach boundary
C. Four feet
D. Whatever is deemed appropriate by the qualified person
4. Shock protection boundaries include the ______________
approach boundaries.
A. Limited, restricted and prohibited
B. Arc flash, prohibited and ultimate
C. Limited, recognized and exclusive
D. Recognized, restricted and common sense
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
3. The default distance for the flash protection boundary is
__________ for equipment up to 600 V.
A. Two feet
B. No further than the restricted approach boundary
C. Four feet
D. Whatever is deemed appropriate by the qualified person
4. Shock protection boundaries include the ______________
approach boundaries.
A. Limited, restricted and prohibited
B. Arc flash, prohibited and ultimate
C. Limited, recognized and exclusive
D. Recognized, restricted and common sense
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Hazard/Risk Categories
Hazard/Risk
Rating system ranking
Category
the relative electrical
hazard of tasks
0
Rated 0 through 4 for low
1
or little risk to relatively
2
high risk
Each category is assigned
2*
a corresponding
3
minimum arc thermal
4
performance value
Minimum
Rating
(Cal/cm2)
N/A
4
8
8
25
40
Category 2 is supplemented by category 2* to assure
protection of the neck, sides and back of the head
Hazard/Risk Categories
Rated Categories are associated
with specific tasks in Table 130.7
(C) (9)
Identify appropriate levels of PPE
Tables 130.7 (C) (8) to (11) are
meant to be used together. They
identify:
– Standard specifications for PPE
– Task Hazard/Risk Category
– Type and kind of PPE
appropriate to the task
–Tables must be used within the
limitations of the Notes for Tables
130.7 (C) (9) and (10)
Provide (C)(8) through
(C)(11)as Handouts
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Table 130.7 (C) (9)
>240 and up to 600 volts
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Table 130.7 (C) (9)
Table 130.7 (C) (9)
Fast acting devices can significantly reduce
– Hazard/risk category
– Energy released in an event
Application of the table is limited by:
– Available short circuit current and
– Maximum fault clearing time
These values must be determined to utilize the table
Overcurrent opening time affects the available arc
flash intensity.
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Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
5. Hazard/Risk categories rank the hazards of electrical tasks
from _________________.
A. 0 for low-risk to 4 for high-risk
B. 0 for no-risk to 4 for excellent-risk
C. 1 for tasks that require no protection to 10 for tasks that
require a licensed electrician
D. Low to high depending on the experience level of the
qualified person actually performing the work
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
5. Hazard/Risk categories rank the hazards of electrical tasks
from _________________.
A. 0 for low-risk to 4 for high-risk
B. 0 for no-risk to 4 for excellent-risk
C. 1 for tasks that require no protection to 10 for tasks that
require a licensed electrician
D. Low to high depending on the experience level of the
qualified person actually performing the work
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Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
6. Insertion and removal of starter buckets from an energized
480 V motor control center is a hazard/risk category of ____.
A. 2*
B. 4
C. Requires only supervisor’s approval
D. 3
7. Voltage testing on a 480 V panelboard with insulated case
circuit breakers requires.
A. Rubber insulating gloves and normal tools
B. Normal tools only
C. Insulated tools only
D. Insulated tools and rubber gloves
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
6. Insertion and removal of starter buckets from an energized
480 V motor control center is a hazard/risk category of ____.
A. 2*
B. 4
C. Requires only supervisor’s approval
D. 3
7. Voltage testing on a 480 V panelboard with insulated case
circuit breakers requires.
A. Rubber insulating gloves and normal tools
B. Normal tools only
C. Insulated tools only
D. Insulated tools and rubber gloves
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Determining the Energy of Possible Arc Flash
An arc flash hazard determination of the available
incident energy requires knowledge of
– the bolted fault current,
– duration of faults, and
– other general equipment information
Operating equipment
Arc Flash Hazard Analysis
Detailed arc flash hazard
analysis is not required
where all of the
following conditions
exist:
– Circuit rated at 240
volts or less
– Circuit is supplied by
one transformer
– Transformer supplying
circuit is rated less
NFPA 70E Article 130.3 Exception No. 1
than 125 kVA
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Arc Flash Hazard Analysis
In lieu of detailed incident
energy analysis
The 130.7 (C) (9) to (11) tables
on hazard/ risk categories
and PPE may be used
Improper maintenance can increase
overcurrent opening time and
incident energy. For more see
• NFPA 70E Chapter 2 on
electrical maintenance
• NFPA 70E hand book and
Safety Program book NFPA 70E Article 130.3 Exception No. 2
Hazard/Risk Categories and Arc Rating
Identifying the hazard/ risk category of a task is
important.
It enables decisions to made about necessary :
– Protective clothing and personal protective
equipment
– Precautions
– Procedures
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Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
8. An arc flash hazard determination of the available incident
energy requires knowledge of _____________________.
A. The closing time of related circuits
B. The bolted fault current and the duration of the faults
C. How long the task is expected to take
D. The distance to the nearest branch disconnect switch
9. Improper maintenance can _____________ overcurrent
opening time and incident energy.
A. Limit
B. Decrease
C. Eliminate
D. Increase
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
8. An arc flash hazard determination of the available incident
energy requires knowledge of _____________________.
A. The closing time of related circuits
B. The bolted fault current and the duration of
the faults
C. How long the task is expected to take
D. The distance to the nearest branch disconnect switch
9. Improper maintenance can _____________ overcurrent
opening time and incident energy.
A. Limit
B. Decrease
C. Eliminate
D. Increase
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Hazard/Risk Categories and Arc Rating
Protective clothing and
other protective gear to be
worn by personnel
working on energized
circuitry is
identified and
described relating
to each hazard/risk
category in Tables
130.7 (C) (10) and
(C) (11) of NFPA
70E.
Hazard/Risk Categories and Arc Rating
Arc rated clothing for
the various hazard/
risk categories is
described in Table
1307 (C) (11)
Avoid work-wear
made with cotton/
polyester blends
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Work Wear for Hazard/Risk Category 0
Long sleeve shirt and long pants
• Non-melting (per ASTM F 1506) or
• Untreated Natural Fiber – wool, silk or cotton
• Safety glasses or goggles
depending on the environment
• Hearing protection (ear canal
inserts)
• Leather gloves over
insulating gloves where
required (e.g.: gloves are
optional for circuit breaker
operation with covers off – 240
volts and below)
• Leather work shoes
Work-Wear for Hazard/Risk Category 1
Flame Resistant Clothing
Minimum arc-rating of 4
• Compliant with ASTM F
1506
• Long-sleeve shirt and
long pants or arc-rated
coverall
• Arc-rated jacket, parka, or
rainwear if needed
Leather work shoes as
needed
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Work-Wear for Hazard/Risk Category 1
Equipment
• Hard Hat
• Leather gloves over
insulating gloves
• Safety glasses or
goggles
• Hearing protection
(ear canal inserts)
• Arc-rated face
shield or
• Arc flash hood - 4
CAL/CM2
Work-Wear for Hazard/Risk Category 2
Flame Resistant
Clothing
• Compliant with ASTM F
1506
• Long-sleeve shirt and
long pants or arc-rated
coverall
• Arc-rated jacket, parka, or
rainwear if needed
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Work-Wear for Hazard/Risk Category 2
Equipment
•
•
•
•
•
•
•
Hard Hat
Leather gloves over insulating gloves
Safety glasses or goggles
Hearing protection (ear canal inserts)
Arc-rated face shield or
Arc flash hood
Leather work shoes as needed
Work-Wear for Hazard/Risk Category 2
*
Same as Category 2 except
An arc flash suit hood with
a minimum arc rating of 8
must be used for head
protection OR
Face shield and
balaclava (sock hood) with
a minimum arc rating of 8
A balaclava covers the
face, head and neck
except for the eye and nose
areas.
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Electrical work - Cautions
Never perform electrical tasks on energized
equipment or circuits exceeding 480 Volts, or of a
hazard/risk category of 3 or 4 (See Table 130.7 (C) (9)
without all of the following:
–Detailed electrical hazard
analysis
–Documented specific
procedure
–Written Energized Work
Permit
–Task qualified personnel
–Appropriate PPE
Hazard/Risk Categories and Arc Rating
Field marking of
equipment
Label must show the
available incident
energy OR required
level of PPE
Circuit components - as
installed - will determine
the incident energy and
the level of hazard
Marking of equipment as
installed is required
NFPA 70E Article 130.3 (C)
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Hazard/Risk Categories and Arc Rating
Working inside the
Limited Approach
Boundary requires the
use of insulated
Tools and
Equipment.
See Table 130.7 (C) (9)
for tasks that require
insulated and
insulating hand tools.
NFPA 70 E Article 130.7 (D)
Hazard/Risk Categories and Arc Rating
Insulated tools and equipment must be:
• Rated for the voltages on which they are used.
• Designed and constructed for the use environment
• Inspected prior to each use for the following:
– Condition of
insulation
– Damage that
may limit tool
performance
– Defects that
increase the
Not an insulated tool
potential for an
incident
NFPA 70 E Article 130.7 (D)
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Hazard/Risk Categories and Arc Rating
There are similar requirements for the
use of other insulated equipment
when necessary
– Fuse or Fuse Holding Equipment
– Ropes and Handlines
– Fiberglass-Reinforced Plastic
Rods
– Portable Ladders
– Protective Shields
– Rubber Insulating Equipment
– Voltage-Rated Plastic Guard
Equipment
– Physical or Mechanical Barriers
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
10. An arc flash rated face shield or hood is required for all live
work at hazard/risk category of __________ and higher.
A. 1
B. 2
C. 2*
D. 0*
11. Working inside the Limited Approach Boundary requires the
use of ____________________.
A. A letter of acknowledgement from OSHA or the NFPA
B. The assistance of a non-qualified person
C. Insulated tools and equipment
D. Increased awareness and scrutiny of relevant codes
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3/21/2014
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
10. An arc flash rated face shield or hood is required for all live
work at hazard/risk category of __________ and higher.
A. 1
B. 2
C. 2*
D. 0*
11. Working inside the Limited Approach Boundary requires the
use of ____________________.
A. A letter of acknowledgement from OSHA or the NFPA
B. The assistance of a non-qualified person
C. Insulated tools and equipment
D. Increased awareness and scrutiny of relevant codes
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
12. A hazard/risk category of ‘1’ requires clothing with a
minimum arc thermal performance rating of at least ______.
A. Optional for PPE
B. Minimum 40 cal/cm²
C. Minimum 4 cal/cm²
D. Minimum 8 cal/cm²
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3/21/2014
Module 3 Unit 3 - 2 Keys to Understanding NFPA 70E
Practice Quiz
12. A hazard/risk category of ‘1’ requires clothing with a
minimum arc thermal performance rating of at least ______.
A. Optional for PPE
B. Minimum 40 cal/cm²
C. Minimum 4 cal/cm²
D. Minimum 8 cal/cm²
Electrical Safety Program - Procedures
Example of a fundamental task and procedure is
proper positioning when branch electrical
connections are made and broken
– Requires discipline
– Well recognized
Stand away
from the panel!
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3/21/2014
Module 3 Unit 3 – 4 Safe Procedures for Electrical Work
Practice Quiz
3. As part of the electrical procedure planning process,
equipment requiring electrical work must be marked to
indicate ________________.
A. The date and time of the scheduled work
B. The Manufacturer, Model No. and Serial No.
C. The available incident energy or required level of PPE
D. The name or number of the employee who will do the work
4. Procedures must be ________________.
A. Job and task specific for the plant
B. Filed with NADCA and OSHA
C. Generic and apply to many different kinds of equipment and
electrical work
D. Ignored if you need to improvise
Module 3 Unit 3 – 4 Safe Procedures for Electrical Work
Practice Quiz
3. As part of the electrical procedure planning process,
equipment requiring electrical work must be marked to
indicate ________________.
A. The date and time of the scheduled work
B. The Manufacturer, Model No. and Serial No.
C.The available incident energy or required level of PPE
D. The name or number of the employee who will do the work
4. Procedures must be ________________.
A.Job and task specific for the plant
B. Filed with NADCA and OSHA
C. Generic and apply to many different kinds of equipment and
electrical work
D. Ignored if you need to improvise
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Electrical Safety Program - Principles
(1) Inspect and evaluate
electrical equipment
(2) Maintain equipment
insulation and
enclosure integrity
(3) Plan every job and
document first-time
procedures
(4) Deenergize, if possible
(5) Anticipate unexpected
events
(6) Identify and minimize
hazards
(7) Protect employees from
– shock,
– burn, blast, and
– Any other hazards
(8) Use the right tools for
the job
(9) Assess people’s abilities
(10) Audit these principles
NFPA 70E Article 110.7
(C) Annex E.1
Thank You For Attending! – Final Questions?
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