ARC FLASH - 2018 NFPA 70E REQUIREMENTS

1. ARC FLASH - 2018 NFPA 70EREQUIREMENTS Presented by United Power Services,Inc.

2. WHAT IS ARCFLASH? A rapid release of energy due to an arching fault between a phase bus bar and another phase bus bar, neutral or ground, where the air is theconductor.

3. ARC-FLASHHISTORY Ralph Lee first called attention to arc-flash explosions in the early1980’s. He noted that an electric arc is 4X as hot as the surface of the sun. (35,000 degreesF) It took a decade for Lee’s concepts to gain acceptance and arc flash was first addressed by OSHA in 1991.

4. THE ARC FLASHHAZARD

5. ARC FAULTS ARE GENERALLY LIMITED TO SYSTEMS WHERE BUS VOLTAGE EXCEEDS 120VOLTS

6. ARC FLASHINJURIES Each year more than 2000 people are admitted to burn centers with severe arc flash burns. Arc flashes can anddo kill at distances of 10ft.

7. MORE ABOUT ARCFLASH • Cause of the arc normally burns away during initial flash – often we do not know the cause of the arcflash • Energy discharge burns bus bars, vaporizes copper and causes an arcblast • The high pressures of the blast can exceed thousands of pounds per squarefoot • Deadly shrapnel is created as the blast dissipates at speeds exceeding 700 mph, fast enough to penetrate the human body • The vaporized copper gives off a toxicgas • The sound associated with an arc flash can exceed160dB • The light from the blast can cause temporaryblindness

8. NFPA 70ECOMPLIANCE • An arc flash risk assessment MUST be done to determine the arc flash risk and determine the arc flashhazards. • The assessment mustinclude: • Estimate of likelihood of occurrence and severity ofinjury • Appropriate safety related workpractices • Arc flash protectionboundary • Calculations for the degree of the arc flashhazard • PPE requirements for work inside arc flash protectionboundary • Training for workers on the hazards of arcflash • Warning labels onequipment • Determination of additional protectivemeasures Companies will be cited and fined fornon-compliance

9. MORE ON NFPA70E COMPLIANCE The arc flash riskassessment: • Must be updated when a major modification or renovationtakes place • Must be reviewed periodically, not to exceed 5years • Take into consideration the design of overcurrent protective device and its openingtime

10. OVERCURRENT PROTECTIVEDEVICES • Fuses and circuitbreakers • Clearing time of overcurrent protective devices determines the severity of an arcflash. • The faster the overcurrent protective device operates, the smaller the“fireball”. • Improper or inadequate maintenance of the overcurrent protective device can result in increased opening time, thus a more severe arc flash than what was calculated willoccur. • It is important to repair all hot spots identified by thermography as soon aspossible.

11. DEFINITION -ARC FLASHBOUNDARY An approach limit at a distance from a prospective arc source within which a person could receive a second degree burn if an electrical arc flash were to occur. It is the distance at which incident energy equals 1.2 cal/cm2. Also equipment installed inside the arc flash boundary may be damaged in the event of an arcflash.

12. DEFINITION - ARC FLASH INCIDENTENERGY The amount of energy impressed on a surface, a certain distance from the source generated during an arc flash event. This is whatburns you. Measured in calorie/cm2

13. ARC FLASHLABELS Electrical equipment such as switchboards, panelboards, industrial control panels, motor control centers and disconnect switches that are likely to require examination, adjustment, servicing, or maintenance while energized must have a label that contains the followinginformation: • Nominal systemvoltage • Arc flash boundary • Incident energy with working distance, or minimum arc rating of clothing, or site specificPPE Exception: Labels applied prior to September 30, 2011 are acceptable if they contain available incident energy or required level ofPPE

14. EXCEPTION TO LABELING NEW IN 2018 NFPA70E In supervised industrial installations where conditions of maintenance and engineering supervision ensure that only qualified persons monitor and service the system, the information required on a label shall be permitted to be documented in a manner that is readily available to persons likely to perform examination, servicing, maintenance, and operation of the equipment whileenergized.

15. EXAMPLELABEL

16. OLDER EXAMPLELABEL

17. LABEL FOR GREATER THAN 40CAL/CM2 MOST DANGEROUS LOCATION AT A FACILITY IS USUALLY ONTHE SECONDARY SIDE OF THE UTILITY TRANSFORMER, WHERE POWER ENTERS THE FACILITY

18. PPE REQUIREMENTS FOR INCIDENTENERGY <1.2 TO 12CAL/CM2 Properly rated ARCClothing ARC rated face shieldwith Balaclava Voltage rated gloves Electrically rated hardhat Insertable earplugs Safety glasses (nometal frames) SafetyShoes

19. PPE REQUIREMENTS FOR INCIDENT ENERGY > 12 CAL/CM2 Properly rated ARC Clothing Arc Flash Hood Voltage ratedgloves Safety Glasses(no metal frames) Electrically rated hard hat Insertable hearing protection SafetyShoes

20. WHAT CAN CAUSE AN ARCFLASH? Removingcovers Taking voltagemeasurements Insertion or removal of Motor Control Buckets and Bus Duct Switches whileenergized Racking a breaker on an energizedbus Putting on or removing grounds after a voltage test Dusty or dirty electrical distribution equipment

21. REDUCING THE ARC FLASHRISK Install fasterfuses Speed up circuitbreakers Upsizewires Remove fuses (over 600A) and replace with circuit breaker with solid state tripunit Periodically clean electrical distribution equipment to prevent build-up of dust and other debris Properly maintain fuses and circuitbreakers