3. Arc Flash What is Arc Flash? What can cause Arc Flash? What are the results of Arc Flash? Standards Shock and Arc Boundaries Levels of PPE Steps to performing an Arc Flash analysis Control Engineering, Inc.
4. What is Arc Flash? The NFPA defines Arc Flash as an electrical explosion caused when current passes through air between ungrounded conductors or between ungrounded conductors and grounded conductors. Control Engineering, Inc.
5. What Can Cause Arc Flash? Accidents Unintentional contact with electrical equipment (screwdriver, pliers, etc.) Equipment failure Improperly designed equipment and/or work procedures. Control Engineering, Inc.
6.
7. Thermal heat (up to 35,000 degrees Fahrenheit, that’s almost four time the surface of the sun!!)
17. Results Continued Can result in serious injuries Critical burns Fatal burns can occur at distances of 10 ft. Collapsed lungs Loss of sight Ruptured eardrums Puncture wounds Death!!! Control Engineering, Inc.
18. Arc Flash Standards OSHA 29 CFR 1910 NEC 110.6 NFPA 70E IEEE 1584 Control Engineering, Inc.
19. OSHA 1910 OSHA 1910.132(d) Where work will be performed within the flash protection boundary, the flash hazard analysis shall determine, and the employer shall document, the incident energy exposure to the worker (in cal/cm2). OSHA 1910.269(I)(6) Flame resistant (FR) clothing and PPE shall be used by the employee based upon the incident energy exposure associated with the specific task. Control Engineering, Inc.
20. NEC 110.6 110.16 Flash Protection. Switchboards, panel boards, industrial control panels, and motor control centers in other than dwelling occupancies, that are likely to require examination, adjustment, servicing, or maintenance while energized, shall be field marked to warn qualified persons of potential electric arc flash hazards. The marking shall be located so as to be clearly visible to qualified persons before examination, adjustment, servicing, or maintenance of the equipment. Control Engineering, Inc.
21. NFPA 70E NFPA 70E-2000 Part II Chapter 2, paragraph 2-1.3.3 states that arc-flash analysis must be performed in order to determine the level of hazard and appropriate PPE for given tasks. Control Engineering, Inc.
22. NEW NFPA 70e Updates NFPA 70E 110.6(E)-requires that all training be documented and employees must show proficiency. NFPA 70E 130.3(C)-AF labels to include, at a minimum, the AF Incident Energy or Level of PPE. Changes to Hazard Category 1 PPE-4 Calories or more for Pants and Face Shield that attaches to Hard Hat. New exception verifies that 240V and less power systems fed by a single transformer less than 125 kv no longer require AF Analysis. Control Engineering, Inc.
27. Note: Distance may be less than or greater than the shock protection boundaries.Flash Protection Boundary Prohibited Restricted Limited Energized part Calculated distance
28. CEI 16 Limits of Approach – Limited Approach Boundary The closest distance an “unqualified” person can approach, unless escorted by a “qualified” person. Prohibited Restricted Limited Energized panel (<750V) 3 feet 6 inches for 480V
29. CEI 17 Limits of Approach – Restricted Approach Boundary Prohibited Restricted The closest distance to exposed live parts a “qualified” person can approach w/out proper PPE and tools. To cross this boundary, the qualified person must wear PPE and have proper tools. Energized part 12 inches for 480 volts
30. CEI 18 Limits of Approach - Shock Prohibited Crossed ONLY by a “qualified” person, which when crossed by body part or object, requires the same protection as if direct contact was made with the live part. Energized part 1 inch for 480 volts
31. CEI 19 Levels of PPE Hazard Risk Category 4 Hazard Risk Category 2 Hazard Risk Category 1 Hazard Risk Category 0 Hazard Risk Category 3
32. Category 0(up to 1.2 Cal/cm2) Shirt (Long-Sleeve) Pants (Long) Safety Glasses V-Rated Gloves Insulated Tools Control Engineering, Inc.
33. Category 1 (1.3 up to 4.0 Cal/cm2) Shirt (Long-Sleeve) FR Pants (Long) FR Face Shield FR V-Rated Gloves Hearing Protection Insulated Tools Hard Hat FR Leather Work Shoes Control Engineering, Inc.
34. Category 2 (4.0 up to 8.0 Cal/cm2) Category 1 Requirements plus Extra Layer of Untreated Natural fiber (Shirt & Pants) Leather Work Shoes Control Engineering, Inc.
35. Category 3 (8 up to 25 Cal/cm2) Category 2 Requirements plus Coveralls up to 2 Sets Double Layer Switching Hood Hearing Protection Control Engineering, Inc.
36. Category 4 (higher than 25 Cal/cm2) Category 3 Requirements plus Flash Suit Control Engineering, Inc.
37. Best way to prevent hazards of electricity…….. Avoid energized circuits is the Safest Way! STOP Before taking any action THINK In terms of Risks and Hazards OPTIONS LOTO Lock Out Tag Out PROTECTION Proper PPE
38. ARC FLASH ANALYSIS STEPS FIELD VERIFICATION AND AUDIT SINGLE LINE DRAWINGS SYSTEM MODELING ARC FLASH ANALYSIS SAFETY PROGRAM ITEGRATION AND TRAINING
67. Pop Quiz What is wrong with this label? Wrong hazard category level of PPE is required? Category 1 What is meant by the limited approach? The closest distance an “unqualified” person can approach, unless escorted by a “qualified” person. What is meant by the prohibited approach? Crossed ONLY by a “qualified” person, which when crossed by body part or object, requires the same protection as if direct contact was made with the live part.
Editor's Notes
This is a presentation for all who want to re-enforce the basics of AFBefore we start have the audience present themselves and what company are they with?Ask the audience who is not familiar with what arc flash is?When did they hear about it?Arc flash analysis at their facilities?
You can also use a Coverall as a replacement for shirts and pants
The purpose of a short circuit analysis is to know what your maximem fault current is at bus.
S.C. is important to and AF analysis because it uses SC parameters (Voltage, Current, time, and distance) to calculate the incident energy angle.