Hazards and Risks when working with Electricity

1. Hazards and Riskswhen working withElectricity

2. What is the best way to prevent the hazards of electricity? Avoiding energized circuits is the safest way!

3. STOP Think before taking Action

4. THINK About the Risks and Hazards

5. OPTIONS Do you have options like: LOTO (Lockout/Tagout)

6. PROTECTION Are you wearing PPE? (Personal Protective Equipment)

7. What are theHazards and Risks? Shock Arc Flash & Arc Blast Fire Ignition

8. SHOCK

9. Shock and its Effects Immediate: Muscle contraction Vital organs damaged Tingling Pain Breathing Disorientation Dizziness Possible death

10. Shock and its Effects Long Term: Memory Loss Nervous disorders Chemical imbalances Damage to vital organs Sometimes fatal

11. Effect of Current on the Body MEN WOMEN Perception Threshold 0.0007 Amps (0.7 mA) Painful Shock 0.006 Amps (6 mA) Cannot Let-Go Level 0.010 Amps (10 mA) Ventricular Fibrillation .100 Amps (100 mA) Heart Failure 0.5 Amps (500 mA) Organ Burn 1.5 Amps (1500 mA) • Perception Threshold 0.001 Amps (1 mA) • Painful Shock 0.009 Amps (9 mA) • Cannot Let-Go Level 0.010 Amps (10 mA) • Ventricular Fibrillation .100 Amps (100 mA) • Heart Failure 0.5 Amps (500 mA) • Organ Burn 1.5 Amps (1500 mA)

12. Two Types of burns from Shock Surface Burns: Caused by entrance and exit of electrical currents through the body Can be caused by a very small amount of current 1st degree to 3rd degree

13. Two Types of burns from Shock Internal Tissue Burns: Caused by current flowing through organs of the body Caused by currents in excess of 1.5 amps 4th degree (internal) Internal organs Typically Fatal

14. How to prevent Shock Place circuits in an Electrically Safe Working Condition by Locking Out and Tagging Out all sources. Verifying that no electrical energy is present.

15. NFPA 70 - NEC The original and primary mission of the NFPA 70 – NEC covered installation of electrical systems. The NFPA 70 – NEC does NOT address the other hazards of electricity.

16. Exposure to Danger The NEC protects individuals from shock hazards under normal conditions. It is NOT designed to protect us from abnormal conditions. We need additional policies to protect from abnormal conditions.

17. Normal Conditions Panel covers in place. Equipment plugged in normally. Normal designed protection in place.

18. Abnormal Conditions Panel covers removed. Equipment temporarily wired. Normal designed protection such as guards, limits switches, etc. NOT in place.

19. Protection fromAbnormal Conditions The Company NFPA 70E OSHA Electrical Safety Procedures Manual Electrical Safety Training

20. Protection fromAbnormal Conditions YOU The first line of defense. Only you can truly keep you safe. Implement Safety Procedures Outlined in the Safety Manual. Only you can ensure that you go home at night.

21. Arc Flash&Arc Blast

23. Arc Flashis a high intensity flash which will also create a very loud noise (blast).

24. The Arc Flash produces: Electric arc that produces the highest temperatures on earth – up to 35,000oF (4 x temp. of the sun). The intense heat causes the sudden expansion of air that results in a blast. All known materials are vaporized at this temperature (copper expands 67,000 times, water 1,670 times).

25. Arc Flash & BlastRelative to the human body: A 2nd degree burn threshold, or a ‘just curable burn threshold,’ is skin temperature raised to 175oF for 0.1 second. A 3rd degree burn threshold, or ‘incurable burn threshold,’ is skin temperature raised to 200oF for 0.1 second. Eardrum damage > 720 psf Lung damage > 1728 psf

26. Arc Flash & BlastRelative to the human body: The hazard may be small for systems of less than 300 volts with limited fault current. Any system over 300 volts probably has the capability to have significant arc flash event.

27. Circuit Breaker Trips When a circuit has been de-energized by a protective device, DO NOT manually re-energize the circuit without first investigating the cause. Do not perform repetitive manual re-closing of breakers or replacing of fuses.

28. Circuit Breaker Operation With Coverson and voltages less than 600V ac rms Safety Glasses Natural Fiber Long Sleeve Shirt Natural Fiber Long Pants Stand to the side

29. Fused Switch Operation With Coverson and voltages less than 600V ac rms Safety Glasses Natural Fiber Long Sleeve Shirt Natural Fiber Long Pants Stand to the side

30. FIRE IGNITION Clothing can be ignited several feet away unless flame resistant (FR) or arc rated (AR) clothing is worn. Note: Synthetics burn ‘into’ the skin when ignited.

31. Clothing There is FR (flame resistant) clothing and AR (arc rated) clothing. ALL clothing with an arc rating (AR) is flame resistant (FR), but not all flame resistant clothing has an arc rating.

32. Clothing Prior to 2015, untreated cotton was considered a safe fabric to wear. Beginning with the change to NFPA – 70E in 2015, arc rated (AR) clothing is required as you will see later in this presentation.

33. Now that you are aware of: shock, arc flash and arc blast, and fire ignition, what do you do about it? Protect Yourself

34. Shock Hazard • Arc Flash and Arc Blast Hazard • Fire Ignition Protect Yourself Against

35. What is required? • Determine the Operating Voltage of the System. • Determine Shock Protection Boundaries. • Determine the Personal Protective Equipment. SHOCK Hazard

36. Determine the Operating Voltage of the System. SHOCK Hazard

37. Determine Shock Protection Boundaries. • a. Limited Approach Boundary – • b. Restricted Approach Boundary – SHOCK Hazard

38. Limited Approach Boundary – An approach limit at a distance from an exposed energized electrical conductor or circuit part within which a shock hazard exists. Approach Boundaries

39. Restricted Approach Boundary – An approach limit at a distance from an exposed energized electrical conductor or circuit part within which there is an increased likelihood of electric shock, due to electrical arc-over combined with inadvertent movement, for personnel working in close proximity to the energized electrical conductor or circuit part. Approach Boundaries

41. Approach Boundaries for Alternating Current Systems Limited Approach Boundary Fixed Phase-to- Phase Voltage Restricted Approach Boundary Less than 50 Not specified Not specified Avoid contact 3 ft. 6 in. 50 – 150 1 ft. 0 in. 151 – 750 3 ft. 6 in.

42. One who has demonstrated skills and knowledge related to the construction and operation of electrical equipment and installations and has received safety training to identify and avoid the hazards involved. Qualified Person

43. 3. Determine the Personal Protective Equipment. a. Use Voltage Rated (VR) Gloves rated greater or equal to the voltage of the system. b. Use Voltage Rated (VR) Tools rated greater or equal to the voltage of the system. SHOCK Hazard

44. OSHA and NFPA 70E both state that qualified electrical workers shall not be asked to work on equipment that is ‘hot’ or ‘live’ except for two demonstrable reasons:

45. 1. De-energizing introduces additional or increased hazards, like an emergency alarm system or a ventilation system.

46. 2. Infeasible due to equipment design or operational limitations, like voltage testing for diagnostics or start up testing. Note: This is the HVACR trade.

47. When you work on ‘live’ circuits, you are open to the hazards and risks of electricity. Therefore, you need to take on the responsibility of protecting yourself. So, how can this be done? Conclusion

48. Prior to 2015, NFPA 70E classified electrical hazards and risks from 0 to 4. • In 2015, Category 0 was eliminated. • The name ‘Hazard/Risk’ was changed to ‘Arc Flash PPE.’ NFPA 70E Hazard/Risk Categories

49. Arc Flash PPEorIncident Energy AnalysisMethods

50. Prior to 2015, selection of PPE was based on Hazard/Risk Categories 0 – 4. • In 2015, selection of PPE is based on either the Incident Energy Analysis Method or Arc Flash PPE Category Method, but not both. How do you select the PPE?