Copyright Progressive Business Publications 1 Arc Flash Protection.
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Transcript of Copyright Progressive Business Publications 1 Arc Flash Protection.
Copyright Progressive Business Publications2
Scary Stats
Hundreds burned every year
2nd and 3rd degree burns to:– Eyes, often causing blindness
– Hands
– Clothed or exposed skin
Lucky ones see their families again
Copyright Progressive Business Publications3
The Basics
Definition: A short circuit through the air that may reach 35,000 degrees F
Insulation or isolation isn’t sufficient
PPE provides insulation
Distance from arc is critical
Copyright Progressive Business Publications4
Underestimating the Risk
Still some mystery about arcs
Some firms underestimate risk
Lockout/tagout and PPE are critical
Copyright Progressive Business Publications5
Arc Flash’s Destructive Force
Hot gases
Molten metal
Intense heat
Blinding flash
Pressure damaging sight, hearing
Flying objects
Copyright Progressive Business Publications6
Many Causes
Dust, impurities on insulating surface
Corrosion
Condensation, dripping water
Spark discharge:
– Accidental contact
– Dropped tools
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Many causes (cont’d.)
Over-voltages across narrow gaps
Failed insulating materials
Improperly designed/utilized equipment
Improper work procedures
Copyright Progressive Business Publications8
Taking Control
We can’t control all causes
We can control:
– PPE, and
– Lockout/tagout
They’re the two critical keys for preventing injuries
Copyright Progressive Business Publications9
Wear PPE – always
PPE is critical for:
– Welding, cutting, brazing
– Work on high-voltage equipment
PPE includes:
– Fire-resistant clothing
– Helmet, headgear
– Face shield, glasses
– Safe gloves, shoes
Copyright Progressive Business Publications10
Risk Categories: Required PPE
Category 0 (no arc risk): safety glasses, pants, long-sleeve shirt
Cat 1 (5 cal/cm2): fire-resistant (FR) clothing; hard hat; leather gloves, shoes; glasses
Cat 2 (8 cal/cm2): face shield; ear plugs; cotton underwear; FR clothing; hard hat; leather gloves, shoes; glasses
Cat 3 (25 cal/cm2): FR coverall; face shield; ear plugs; cotton underwear; FR clothing; hard hat; leather gloves, shoes; glasses
Cat 4 (40 cal/cm2): full flash suit with hood; FR coverall or clothing; face shield; ear plugs; cotton underwear; hard hat; leather gloves, shoes; glasses
Copyright Progressive Business Publications11
Lockout/Tagout
Step 1: Notify employees
Step 2: ID power source(s)
Hard-wired equipment requires locking, tagging out circuit
Copyright Progressive Business Publications12
Lockout/tagout (cont’d.)
Step 3: Disconnect power
– Circuits
– Energy-isolating devices
– Multiple energy sources
Step 4: Apply locks, tags
Copyright Progressive Business Publications13
Lockout/tagout (cont’d.)
Step 5: Drain stored energy
Step 6: Test equipment
If equipment starts up,repeat all 6 steps
Copyright Progressive Business Publications14
Boundaries and Labels
FPB – flash protection boundary
Arc flash labels tell you:
– The FPB
– Required PPE
– Shock hazard
– Arc energy (cal/cm2)
– Restricted approach distance
– Prohibited approach distance