1. 1 ELECTRICAL HAZARDS

2. www.IndTraining.com2 ELECTRICAL HAZARDS SHOCK. Electric shock occurs when the human body becomes part of the path through which current flows. The direct result can be electrocution. The indirect result can be injury resulting from a fall or movement into machinery because of a shock

3. www.IndTraining.com3 ELECTRICAL HAZARDS BURNS. Burns can result when a person touches electrical wiring or equipment that is energized. ARC-BLAST. Arc-blasts occur from high- amperage currents arcing through the air. This can be caused by accidental contact with energized components or equipment failure.

4. www.IndTraining.com4 ELECTRICAL HAZARDS ARC-BLAST. The three primary hazards associated with an arc-blast are: Thermal radiation. Pressure Wave. Projectiles.

5. www.IndTraining.com5 ELECTRICAL HAZARDS EXPLOSIONS. Explosions occur when electricity provides a source of ignition for an explosive mixture in the atmosphere.

6. www.IndTraining.com6 ELECTRICAL HAZARDS FIRES. Electricity is one of the most common causes of fires both in the home and in the workplace. Defective or misused electrical equipment is a major cause.

7. www.IndTraining.com7 EFFECTS ON THE HUMAN BODY Depends on: Current and Voltage Resistance Path through body Duration of shock

8. www.IndTraining.com8 Effects of AC Electricity More than 3 mA- Painful shock- cause indirect accident More than 10 mA- Muscle contraction – “No Let Go” danger More than 30 mA- Lung paralysis, usually temporary

9. www.IndTraining.com9 Effects of AC Electricity More than 50 mA- Ventricular fibrillation, usually fatal 100 mA to 4 A- Certain ventricular fibrillation, fatal Over 4 A- Heart paralysis, severe burns

10. www.IndTraining.com10 1910.303(b) Examination of equipment Electrical equipment must be free of recognized hazards that are likely to cause death or serious physical harm to employees.

11. www.IndTraining.com11 1910.303(b) Examination of equipment Safety of equipment must be determined using the following considerations: Suitability for installation and use Mechanical strength and durability Electrical insulation Heating effects under conditions of use

12. www.IndTraining.com12 1910.303(b) Examination of equipment Safety of equipment must be determined using the following considerations: Arcing effects Classification by type, size, voltage, current capacity and specific use Other factors

13. www.IndTraining.com13 1910.303(c) Splices Conductors must be spliced with: Splicing devices suitable for the use Brazing, welding or soldering (with a mechanically and electrically secure joint before soldering & then soldered)

14. www.IndTraining.com14 1910.303(c) Splices All splices and joints and the free ends of conductors must be covered with an insulation equivalent to that of the conductors or with an insulating device suitable for the purpose.

15. www.IndTraining.com15 1910.303(e) Marking Electrical equipment may not be used unless the manufacturer’s name, trademark or other identification is on the equipment.

16. www.IndTraining.com16 1910.303(e) Marking Other markings must be provided giving voltage, current, wattage, or other ratings as necessary. Markings must be durable enough to withstand the environment.

17. www.IndTraining.com17 1910.303(f) Identification Each disconnecting means must be legibly marked to indicate its purpose, unless located and arranged so that its purpose is evident.

18. www.IndTraining.com18 1910.303(f) Identification These markings must be durable enough to withstand their environment.

19. www.IndTraining.com19 1910.303(g)(1) 600 volts, nominal, or less Working space about electrical equipment. This section refers to a person qualified to work on electrical equipment, usually an electrician.

20. www.IndTraining.com20 1910.303(g)(1)(i) Working clearances Except as required or permitted, the dimension of the working space in front of live parts (operating at 600 volts or less) and likely to require examination, adjustment, servicing, or maintenance must be at least three feet.(See table S-1).

21. www.IndTraining.com21 1910.303(g)(1)(i) Working clearances The workspace in front of electrical equipment must not be less than 30 inches wide.

22. www.IndTraining.com22 1910.303(g)(1)(ii) Working clearances Working spaces required for this standard may not be used for storage.

23. www.IndTraining.com23 1910.303(g)(2) 600 Volts or less Guarding of live parts operating at 50 Volts or more. The purpose of this requirement is to protect any person who is in the vicinity of electrical equipment against accidental contact, not just electricians.

24. www.IndTraining.com24 1910.303(g)(2) 600 Volts or less Guarding of live parts. (i)Guard against accidental contact by: (A)Location accessible only to qualified persons (B)Permanent, substantial partitions or screens

25. www.IndTraining.com25 1910.303(g)(2) 600 Volts or less Guarding of live parts. (i)Guard against accidental contact by: (C) Location on a suitable elevated balcony or platform (D) Elevation of 8 feet or more above the floor or other working surface

26. www.IndTraining.com26 1910.303(g)(2) 600 Volts or less Guardian of live parts. In locations where electrical equipment would be exposed to physical damage, enclosures or guardians must be so arranged and of such strength as to prevent such damage.

27. www.IndTraining.com27 1910.303(h)(3) Over 600 Volts Workspace around equipment. Sufficient space must be provided and maintained around electrical equipment to permit ready and safe operation and maintenance.

28. www.IndTraining.com28 1910.303(h)(3)(ii) Illumination (Over 600 Volts) Adequate illumination must be provided for all working spaces around electrical equipment. The lights and switches must be arranged so that persons making repairs or turning on lights wont contact live ports.

29. www.IndTraining.com29 1910.303(h)(3)(iii) Elevation of unguarded live parts Unguarded live parts above working space must be maintained at elevations not less than specified in Table S-3. The minimum is 8 feet.

30. www.IndTraining.com30 1910.304(a) Grounded and grounding conductors (1) Identification of conductors. The grounded conductor is an energized circuit conductor that is connected to earth through the system ground. It is commonly referred to as the neutral.

31. www.IndTraining.com31 1910.304(a) Grounded and grounding conductors (1)Identification of conductors. The equipment grounding conductor is not an energized conductor under normal conditions. It is energized only if there is a leak or fault in the normal current path and directs current back to the source.

32. www.IndTraining.com32 1910.304(a) Grounded and grounding conductors (1)Identification of conductors. The National Electric Code requires that: The grounded conductor (neutral) be continuous white or natural gray. The equipment grounding conductor be green, green with yellow stripes or bare.

33. www.IndTraining.com33 1910.304(a)(2) Polarity of connections No grounded conductor may be attached to any terminal or lead so as to reverse designated polarity.

34. www.IndTraining.com34 1910.304(a)(2) Polarity of connections Reversed polarity is a condition when neutral conductor is incorrectly connected to the “hot” terminal of a plug, receptacle or other connector.

35. www.IndTraining.com35 1910.304(e) Overcurrent protection (1) 600 volts or less. (i) Conductors and equipment must be protected from overcurrent.

36. www.IndTraining.com36 1910.304(e) Overcurrent protection (1) 600 volts or less. Fuses and circuit breakers are designed to disconnect a circuit from its supply source when a maximum allowable heat is reached.

37. www.IndTraining.com37 1910.304(e) Overcurrent protection (1) 600 volts or less (iv) Location. Overcurrent devices must be readily accessible but not located where they will be exposed to physical damage or in the vicinity of easily ignitable material.

38. www.IndTraining.com38 1910.304(f) Grounding (4) Grounding path. The path to ground from circuits, equipment, and enclosures must be permanent and continuous

39. www.IndTraining.com39 1910.304(f) Grounding (5)(v) Tools likely to be used in wet and conductive locations need not be grounded if supplied through an isolating transformer with an ungrounded secondary of not over 50 volts.

40. www.IndTraining.com40 1910.304(f) Grounding (5)(v) Listed or labeled portable tools and appliances protected by an approved system of double insulation, or its equivalent, need not be grounded. However, they must be distinctively marked.

41. www.IndTraining.com41 Electrical Tools Double Insulated They work with GFCIs Casing must be labeled Tool must be inspected Extension cord must be three-prong

42. www.IndTraining.com42 1910.305 (a)Wiring methods. (1) General requirements. (ii) No wiring system of any type shall be in ducts used to transport dust, loose stock or flammable vapors, or used for vapor removal or ventilation of commercial-type cooking equipment.

43. www.IndTraining.com43 1910.305 (a)Wiring methods. (2) Temporary wiring. Temporary electrical power and lighting wiring may be of a class less than would be required for a permanent installation.

44. www.IndTraining.com44 1910.305 (a)Wiring methods. (2) Temporary wiring. (i)Uses permitted, 600 volts or less. (A) During and for remodeling, maintenance repair, or demolition or similar activities.

45. www.IndTraining.com45 1910.305 (a)Wiring methods. (i)Uses permitted, 600 volts or less. (B) For experimental or developmental work (C) For a period not to exceed 90 days for Christmas decorative lighting, carnivals, and similar purposes.

46. www.IndTraining.com46 1910.305 (a)Wiring methods. (2) Temporary wiring. (i)Uses permitted, over 600 volts. Only during tests, experiments and emergencies.

47. www.IndTraining.com47 1910.305 (a)Wiring methods. (F) Lamps for general illumination must be protected from accidental contact or breakage. Protection can be provided by an elevation of 7 feet or by a suitable fixture with a guard.

48. www.IndTraining.com48 1910.305 (a)Wiring methods. (G) Flexible cords and cables must be protected from accidental damage.Sharp corners or projections must be avoided. Protection must be provided when passing through doorways or other pinch points.

49. www.IndTraining.com49 1910.305(b)(1) Conductors entering boxes, cabinets, or fittings. Conductors entering boxes, cabinets, or fittings must be protected from abrasion. Unused openings in cabinets, boxes, and fittings must be effectively closed.

50. www.IndTraining.com50 1910.305(b)(2) Electrical box covers All pull boxes, junction boxes, and fittings must be provided with approved covers. Metal covers must be grounded.

51. www.IndTraining.com51 1910.305(b)(2) Electrical box covers Outlet boxes must have a cover or a faceplate. Outlet box covers with holes for flexible cords must bushings or smooth, well- rounded surfaces.

52. www.IndTraining.com52 1910.305 (d)Switchboards and panelboards. Panelboards must be mounted in approved cabinets or boxes and must be dead front. Others are accessible only to qualified persons.

53. www.IndTraining.com53 1910.305(g)(1)(i) Flexible cords and cables. Allowed uses: Pendants Wiring fixtures Portable lamps or appliances Elevator cables Wiring cranes or hoists

54. www.IndTraining.com54 1910.305(g)(1)(i) Flexible cords and cables. Allowed uses: Connect stationary equipment to facilitate frequent interchange Prevent transmission of noise or vibration For removal for maintenance/repair

55. www.IndTraining.com55 1910.305(g)(1)(iii) Flexible cords and cables. May not be used: As a substitute for the fixed wiring of a structure. Where run through holes in walls, ceilings or floors.

56. www.IndTraining.com56 1910.305(g)(1)(iii) Flexible cords and cables. May not be used: Where run through doorways, windows, or similar openings Where attached to building surfaces Where concealed behind building walls, ceilings, or floors.

57. www.IndTraining.com57 1910.305(g)(2) Flexible cords and cables. (ii) Flexible cords must be used only in continuous lengths without splice or tap.

58. www.IndTraining.com58 1910.305(g)(2) Flexible cords and cables. (ii) Hard service flex cords, No. 12 or larger, may be repaired if spliced so that the splice retains the insulation, outer sheath properties, and usage characteristics of the original cord.

59. www.IndTraining.com59 1910.305(g)(2) Flexible cords and cables. (iii) Flexible cords must be connected to devices and fittings so that strain relief is provided which will prevent pull off from being directly transmitted to joints or terminal screws.

60. www.IndTraining.com60 1910.305(j) Equipment for general use. (2)(ii) A receptacle installed in a wet or damp location must be suitable for the location.

61. www.IndTraining.com61 1910.307 Hazardous (classified) locations. (b) Electrical installations. Equipment, wiring, and installations of equipment in hazardous (classified) locations must be intrinsically safe, approved for the location, or safe for the location.

62. www.IndTraining.com62 Hazardous Locations Class I locations Locations in which flammable gasses or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures.

63. www.IndTraining.com63 Hazardous Locations Class I, Division 1 Location in which hazardous concentrations of flammable gases or vapors may exist: (a) Under normal operating conditions (b) Because of repair or maintenance operations or leakage (c) Because of breakdown or faulty operation

64. www.IndTraining.com64 Hazardous Locations Class I, Division 2 Location in which flammable gases or vapors are: (a) Normally confined within closed containers or systems (b) Normally kept below hazardous concentrations by ventilation (c) Normally kept below hazardous concentrations by positive-pressure ventilation (adjacent to Division 1)

65. www.IndTraining.com65 Hazardous Locations Class II Locations Locations which are hazardous because of the presence of combustible dust.

66. www.IndTraining.com66 Hazardous Locations Class II, Division 1 Location where combustible dust may be present due to: (a) Normal operations (b) Mechanical failure or abnormal operation of machinery or equipment (c) combustible dust of an electrically conductive nature may be present.

67. www.IndTraining.com67 Hazardous Locations Class II, Division 2 Location where: (a) Combustible dust will not normally be in suspension in ignitable quantities (b) Dusts may be in suspension as a result of an infrequent malfunction of handling or processing equipment.

68. www.IndTraining.com68 Hazardous Locations Class III Locations Locations that are hazardous because of the presence of easily ignitable fibers or flyings but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitable mixtures.

69. www.IndTraining.com69 Hazardous Locations Class III, Division 1 Locations in which easily ignitable fibers or materials producing combustible flyings are handled, manufactured or used.

70. www.IndTraining.com70 Hazardous Locations Class III, Division 2 Location in which easily ignitable fibers are stored or handled, except in the process of manufacture.

71. www.IndTraining.com71 1910.331 -.335 Electrical Safe Work Practices Covers work practices rather than electrical equipment and installations. This should be a part of your Lockout/Tagout program

72. www.IndTraining.com72 Electrical Protective Equipment 29 CFR1910.137 (59 FR 4435) (a)Design Requirements (b)In-service Care and Use

73. www.IndTraining.com73 Electrical Protective Equipment 29 CFR1910.137 (59 FR 4435) (a)Design Requirements Insulating blankets,matting, covers, line hose, gloves, and sleeves made of rubber shall meet specified requirements for manufacture, marking, electrical properties, workmanship and finish.

74. www.IndTraining.com74 (b) In-service Care and Use Electrical protective equipment shall be maintained in a safe, reliable condition. Specific requirements for in-service care and use are given for insulating blankets, covers, line hose, gloves, and sleeves made of rubber.

75. www.IndTraining.com75 Qualified Employee (Qualified Person) One knowledgeable in the construction and operation of the electric power generation, transmission, and distribution equipment involved, along with the associated hazards.

76. www.IndTraining.com76 Qualified Employee (Qualified Person) Must have the training required by paragraph(a)(2)(ii). Has undergone on-the-job training and has demonstrated an ability to perform duties safely under the direct supervision of a qualified person.

77. www.IndTraining.com77 One employee was climbing a metal ladder to hand an electric drill to the journey installer on a scaffold about five feet above him. When the victim reached the third rung from the bottom of the ladder he received an electric shock that killed him.

78. www.IndTraining.com78 The employee was attempting to correct an electrical problem involving two non-operational lamps. He proceeded to the area where he thought the problem was. He had not shut off the power at the circuit breaker panel nor had he tested the wires to see if they were live. He was electrocuted when he grabbed the two live wires with his left hand and then fell from the ladder.

79. www.IndTraining.com79 Review What are Electrical Hazards? Why is it important to examine equipment? How do we identity Electrical Hazards?

80. www.IndTraining.com80 The material presented in this slide show presentation is for reference purposes only. In no way is the material in substitution for any federal or state regulation.