Welcome Arc Flash Regulations & Requirements

Updated 12/07

Arc Flash

Regulations & Requirements OR

How to work “live” without making an

ash

of yourself *

* Credit to Regional OSHA Training Coordinator

Arc flash is a short circuit through air that flashes over from one exposed live conductor to another conductor or to ground.

Lightning is an example of a naturally occurring arc flash.

Electric Arc Facts 

TYPICALLY LASTS LESS THAN A SECOND



EXTREMELY HIGH RADIANT ENERGY



EXPLOSIVE IN NATURE



CAN IGNITE AND/OR MELT CONVENTIONAL WORK CLOTHING

Slide Courtesy of Oberon

15000 °C < 740 mph IR 165 db Visible UV 1000 °C 2000 psf 50 cal/cm 2

From Arc Flash:

 Severe burns from heat and molten metal  Damage to eyesight

From Arc Blast:

 Loss of brain function due to concussion  Hearing loss from ruptured eardrums  Shrapnel wounds from flying metal parts  Other injuries from force of explosion



Most hospital admissions due to electrical accidents are from arc flash burns, not from electrical shocks!

 Of the 350 workers killed by electricity in 2005,

50%

were related to arc flash  5 to 10 arc flash incidents occur in the USA each day, resulting in an average estimated

1 death every other day



DEATH …

  Or years of medical treatment, with costs from severe burns

$1-5 million

for   Victim may never return to work or enjoy same quality of life!

 OSHA fines,

civil lawsuits

 Equipment damage, production loss

The First Rule About Working “Live”

Bottom Line

 DON’T! De-energize and Lockout/Tagout instead.  80% of the electrical fatalities in this country occur where the power could have been off.

 Reasons Given For Working Live:  Not wanting to pay overtime  Slows production down  Takes too long - inconvenient  “Safety has priority over service continuity, equipment damage or economics”…

Institute of Electrical and Electronic Engineers ‘Buff Book’

OSHA 1910.333(a)(1) De-energized Parts “Live parts to which an employee may be exposed shall be de-energized before the employee works on or near them, unless the employer can demonstrate that de-energizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations.”

 Accidental contact or even just positioning a conductive object too close to high-amp current  Sparks (dropping tools, racking breakers, etc.)  Equipment or circuit breaker failure  Breaks or gaps in insulation  Dust, corrosion, other impurities  Fumes or chemical vapors

 Installing conduits & bus duct switches  Working on control circuits  Cleaning starter buckets in a MCC  Applying safety grounds  Operating disconnect switches and breakers  Taking a voltage reading  Removing, installing circuit breakers or fuses  Anytime you’re inside the Flash Protection Boundary



OSHA 29 CFR Subpart S, 1910.331 – 335

“Electrical Safety Related Work Practices” 

NFPA 70E-2004

Workplace” “Standard For Electrical Safety In The 

To order call 800-344-3555 or go to www.nfpacatalog.org



IEEE 1584

Calculations” “Guide For Performing Arc Flash Hazard 

To order call 800-701-4333 or go to http://standards.ieee.org



ANSI / NFPA 70-2005

National Electric Code

NFPA 70E

OSHA IS THE

SHALL &

NFPA 70E IS THE

HOW

 Industry consensus standards, notably NFPA 70E, can be used by employers as guides to making the assessments and equipment selections required by the standard. Similarly, in OSHA enforcement actions, they can be used as evidence of whether the employer acted reasonably.

 Objective of arc flash regulations is to limit injury to curable

2 nd degree burns

.

 Adhering to min. requirements does

NOT:

 Eliminate risk of burn injury completely  Protect workers from effects of arc blast

 Incident energy determined by:  Magnitude of fault current  Duration of arc fault  Distance from flash source  Research shows that incident energy of approx.

1.2 cal/cm²

will cause a 2 nd degree burn.

 Flash protection boundary should be set at point where incident energy equals 1.2 cal/cm²  When work on live exposed parts is in progress:  Unprotected workers must remain outside flash protection boundary.

 Workers inside boundary must wear proper flash protection clothing.

NFPA 70E defines five levels of arc flash hazards:

Category 0

(low risk) through

Category 4

(high risk)

Protective apparel requirements shown in table 130.7(C)(10) of NFPA70E-2004

0 1 2 3 4

Cat.

Arc Rating

NA 4 cal / cm² 8 cal / cm² 25 cal / cm² 40 cal / cm²

Clothing Description

Non-melting, flammable materials (ie., untreated cotton, wool, rayon, or silk,or blends of these materials) with a fabric weight at least 4.5 oz / yd² [1 layer] FR shirt and FR pants or FR coverall [1 layer] Cotton underwear (conventional short sleeve and brief/shorts), plus FR shirt and FR pants [2 layers] Cotton underwear plus FR shirt and FR pants plus FR coverall, or cotton underwear plus two FR coveralls. [3 layers] Cotton underwear plus FR shirt and FR pants plus multilayer flash suit [3 or more layers]

Protective equipment requirements are covered in Table 130.7(C)(10) of NFPA70-2004 Hard hat FR hard hat liner Safety glasses or goggles Arc-rated face shield Flash suit hood Hearing protection Leather gloves Leather shoes Category 0 X Category 2 X X X X X X Category 4 X X X X X X X

Before arc flash During arc flash

Untreated cotton shirt (5.7 oz/yard²)

After arc flash

Before arc flash During arc flash

DuPont NOMEX® IIIA Shirt (4.5 oz/yd²)

After arc flash

The flash hazard category can be determined in either of two ways:  Use table 130.7(C)(9)(a) Hazard / Risk Category Classification in NFPA 70E-2004  Perform flash hazard analysis as described in 130.3 of NFPA 70E-2004

Article 110.16 of the ANSI / NFPA 70-2005 National Electric Code states:

“

Switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers

that are in other than dwelling occupancies and are likely to be subject to

examination, adjustment, servicing or maintenance while energized

must be field marked to warn qualified personnel of potential arc flash hazards. The marking shall be located so as to be clearly visible to qualified persons before examination, adjustment, servicing or maintenance of equipment.” NEC2008 Adds: - Electrical equipment such as…… - Multiple occupancy dwellings not exempt

 Labeling is responsibility of

owners

, not equipment manufacturers or suppliers.

 Applies to all

new

installations and as well as any existing installations that are

added, altered or modified

in any way.



Many companies taking safe (and efficient) approach of labeling all existing installations.

 Current regulation says only that label must warn of arc flash hazards. 3.5” x 5” 2” x 4” Bilingual (En/Sp) labels also available

 Many employers including additional info such as hazard category and required arc flash PPE  Others also providing shock hazard information

Labels with preprinted hazcat and PPE mean less writing, less chance of someone making a mistake

 Send data in spreadsheet and have Brady print for you  Print using Brady industrial label printing systems

MarkWare™ Software + GlobalMark® printer or MiniMark™ printer

Print arc flash labels to Brady industrial labeling printers direct from 3-party power management programs such as: SKM ETAP ESA EasyPower

 Required by NFPA 70E when working live  Allows relevant hazards and safe work practices to be specified on a job by job basis  Ensures proper mgmt control of high-risk work activities

Promote awareness of the dangers associated with arc flash accidents And make sure your employees know how to protect themselves!

 Lockout before service and maintenance  Follow approved safe work procedures  Wear proper protective apparel and equipment  Use insulated gloves, tools, blankets and barriers  Keep equipment free of dirt and corrosion  Operate equipment at the rated voltage  Be careful to avoid generating sparks



Other areas where Brady can help:

 Lockout / Tagout  Hazardous chemicals / Right-to-Know  Slips & Trips  Process & equipment identification  5S and Lean Manufacturing  Production tracking and product labeling