Personal Protective Equipment
For Electrical Hazards
What’s New
In February 1972, OSHA incorporated the 1971 edition of
the National Fire Protection Association's (NFPA) National
Electrical Code (NEC), NFPA 70-1971
On January 16, 1981, OSHA revised its Electrical standard
with Part I of National Fire Protection Association's (NFPA)
70E - 1979
On August 13, 2007, OSHA revised its Electrical standard to
reference National Fire Protection Association's (NFPA) 70E
- 2000
Arc Flash Event
A dangerous release of energy created by an electrical fault
 Release will contain:
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Thermal energy
Acoustical energy
Pressure wave
Debris
Arc Flash Intensity
Variables that effect the size and energy of an electric arc flash:
 Amperage
 Voltage
 Arc Gap
 Closure time
 Distance away from arc
 3 phase v single phase
 Confined space
Arc Energy Basics
 Exposure energy expressed in cal/cm2
 ½ to 1 cal/cm2 = hottest part of lighter in 1 sec
 1-2 calorie exposure will cause second degree burn on human skin
 Typical non-FR workwear can ignite @4-5cals
 Arcs typically release 5-30 cals - energies of 30-60 cals are not uncommon
Arc Flash Events
 Can reach 35,000 F
 Fatal burns >10 feet
 Majority of hospital
admissions are arc flash
burns, not shock
 30,000 arcs and 7000 burn
injuries per year
 Over 2000 people admitted
to burn centers yearly with
severe arc flash burns
Why is FR Needed?
• Most severe burn energies and
fatalities are caused by nonflame resistant clothing igniting
and continuing to burn
• Flame resistant clothing will selfextinguish, thus limiting the
injury
• Body area under non-FR
clothing is often burned more
severely than exposed skin
What Is a Burn?
A chemical process which progressively
injures skin; severity relates to depth
 1st : redness, pain – not permanent
 2nd: blistering – skin will regenerate
 3rd: total skin depth destroyed. Will
not regenerate – requires grafting
 4th : Underlying muscle damaged
Burn Survival
 Burn percentage, more than severity, predicts survival
because skin is infection barrier
 2nd and 3rd degree break skin, providing an infection pathway
 Most hospital deaths 2-4 weeks post-exposure are infection
Flash Protection Boundary
Flash Protection Boundary (outer boundary): The flash
boundary is the farthest established boundary from the
energy source. If an arc flash occurred, this boundary is
where an employee would be exposed to a curable second
degree burn (1.2 calories/cm2)
Prohibited Approach Boundary
Prohibited Approach (inner boundary): A distance from an
exposed part which is considered the same as making contact
with the live part.
“Working On Live Parts”
Occurs when coming in contact with live parts, including test equipment, body,
PPE, tools etc. . .
Arc Energy vs Distance
Energy goes up dramatically as distance from arc drops:
EXAMPLE: 22,000A, 480V, 6 cycles:
24”
18”
15”
12”
2.7 cal. 3.2 cal. 7.5 cal. 12.2 cal.
10”
18 cal.
How close are you to the arc?
Hot Work Requirements
Employer must develop and enforce safety-related work practices
to prevent electric shock or other injuries resulting from either
direct or indirect electrical contacts.
These safety related work practices could include:
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Energized Electrical Work Permit
Pre-work Job Briefing
Personal Protective Equipment
Insulated Tools
Written Safety Program
Qualified Person Training
Flash Hazard Labeling
Flash Protection Labeling
Arc Flash Hazard labeling must be posted which identifies:
• Approach boundaries
• PPE required
How to Determine Boundaries
NFPA Tables: Refer to NFPA 70E – 2000 Table 3-3.9.1 or Table
130.7(C)99)(a) NFPA 70E – 2004.
Pro: Easiest and quickest method
Con: Provides the least amount of accuracy. Limited tasks are
covered in tables
How to Determine Boundaries
Formula Method: NFPA 70 E and IEEE Standard 1584 provides
formulas that can be used to accurately determine the
approach boundaries.
Pro: More accurate and all inclusive than NFPA tables
Con: Is time consuming, requires an engineer level of expertise
and is subject to human error.
How to Determine Boundaries
Approach Calculator: IEEE and others have provided a
spreadsheet based calculator to assist in determining approach
boundaries.
Pro: Quicker than formula method
Con: Still requires detailed information about the equipment
and circuit often requiring the use of an electrical engineer.
How to Determine Boundaries
Software:There exists on the market various software
products that can simplify and expedite the approach
boundary calculations.
Pro: Creates one-line diagrams and arc flash labels based on
data entered
Con: Cost and equipment / circuit knowledge is still required
often requiring an engineer.
What is Flame Resistant Clothing?
• Clothing made from fabrics
that self-extinguish
• Fabrics may be natural or
synthetic
• Designed to limit (not
eliminate) burn injury
• Survival, extent of injury,
recovery time and quality of
life are all dependent on FRC
performance
Engineered Flame Resistant Fabrics
• Natural fibers
• Synthetic fibers
• Natural / synthetic blends
NOTE: Flame resistance must be durable to launderings,
wear, the environment, etc. for the service life of the
garment
Look for proven products!
New World of FRC
• FRC used to be perceived as ugly, uncomfortable,
expensive, scratchy, hot and not breathable
• Major shift last 3-5 years to lighter, softer more
breathable fabrics and to styles virtually identical to
“street clothing”
• Examples include Nomex/Rayon blends, Indura &
UltraSoft® knits, fleeces, denims.
The 70E Solution
Confused by the selection process?
National trend is single layer HRC 2 daily wear
and HRC 4 flash gear
Don’t let confusion delay your PPE selection!
Proper Use
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FRC should be appropriate to hazard
Always the outermost layer
Worn correctly; zipped, buttoned, etc
All natural, non-melting undergarments
Clean, no flammable contaminants
Repaired correctly and removed from
service when needed