Electric Shock Drowning. 07/22/2015 Ed Lethert

Transcription

1 Electric Shock Drowning

2 Thanks to Gary Hughes Greg Nybeck LMCD Board 2

3 Edward "Ed" Lethert Electric Shock Drowning Safety Specialist New Hope, MN Background Lakeshore Weekly News Article 3

4 Lake Minnetonka Boater Member: Minnetonka Power Squadron 4

5 ELECTRIC SHOCK DROWNING PREVENTION ASSOCIATION 5

6 AWARENESS PREVENTION 6

7 This evening's presentation Non-Technical A subset of the complete ESD Presentation (approx 1½ hours) The full presentation can be made to interested entities upon request Thanks 7

8 Questions Questions and comments are welcome and encouraged immediately following the presentation Presenter will also be available after the meeting to address additional questions 8

9 Thanks to Capt. David Rifkin and Kevin Ritz for permission to use some of their material. 9

10 Of all the people I have spoken with, almost no one appears to have heard of Electric Shock Drowning Recent Question to Lakeshore Property Owner: "Is the circuit that powers your electrically operated boat lift protected by a Ground Fault Circuit Interrupter?" Response: "I have no idea." 10

11 Objectives To Answer the Following What is Electric Shock Drowning? (also known as "ESD") What conditions can cause ESD? Can water leakage currents or voltage gradients be detected or measured? Are there serious danger thresholds? Are there standards, policies and procedures for minimizing the risk of ESD? 11

12 Applicable Installations/Facilities Marina Facilities Private Docks * RV Parks, Campgrounds, etc. Swimming pools, spas, ponds, etc. Submersible Pumps Agricultural Irrigation Canals Manhole covers (New York City - "Street Zaps") 12

13 This subject material applies directly to ANY environments where electric circuits and equipment operate in, on, or near a body of water 13

14 Why Cause for Concern? Increase in use of electrically operated equipment in and around recreational (and non-recreational) waters Increase in Do-It-Yourself electrical work by unqualified individuals Lack of inspections by the Authority Having Jurisdiction (electrical inspections) Less caution exercised by the public More litigious culture 14

15 ESD Victims 15

16 Lost to ESD Comment: Samantha Chipley Article 16

17 Lost to ESD Marcus Colburn, age 21, died as a result of ESD on Father s Day, June 21st, 2015 Comment: Circuit Breaker 17

18 James D. Shafer and Capt. David Rifkin (USN, Ret) have compiled a database of known ESD incidents going back as far as the mid-1980s It's the only known list of its kind It is updated by Capt. Rifkin as each new ESD related incident becomes known 18

19 It is believed that the actual number of ESD fatalities is much higher than known or reported as paralysis due to small electric currents passing through the body is not recognizable postmortem as the cause of the drowning 19

20 Electrical Safety Around Water 20

21 This goes without saying 21

22 As does this I hope 22

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25 The possibility of an in-the-water shock hazard exists wherever shore-powered AC electrical equipment is located in the water, over the water, or near the water Awareness of and mitigation of in-water shock hazards (the cause of ESD) is of vital importance 25

26 90.1 Purpose. National Electrical Code (A) Practical Safeguarding. The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity NEC (NFPA 70) 26

27 "practical safeguarding of persons" Standards Laws Regulations WV, TN, KY, MO, etc. MN? Quality and Skilled Workmanship Inspection by Competent Authority Ongoing Monitoring and Inspection EDUCATION OF THE PUBLIC Comment: Legislative actions MN DLI Electrical Inspections Div 27

28 Electric Shock Drowning 28

29 Electric Shock Drowning (ESD) is a unique form of drowning caused by waterborne alternating currents (AC) These currents can produce dangerous voltage gradients in the water The voltage gradients can cause an electrical current to flow through the body of an individual in the water 29

30 The thru-body current produced by the voltage gradient, if sufficiently high, can paralyze the body's muscles, inhibiting one's ability to swim, or even to move one's limbs or worse The outcome in most ESD cases is that an otherwise healthy individual drowns (water in the lungs) 30

31 These thru-body currents, depending on their magnitude, can: Paralyze skeletal muscles Cause respiratory paralysis (shut down the lungs) Initiate ventricular fibrillation Result in full cardiac arrest 31

32 ESD is not exactly the same as death by electrocution, which usually results from direct contact with energized metal objects or surfaces In-water electrocutions are included in the definition of ESD because they are caused by the same fault conditions that cause an ESD fatality 32

33 According to OSHA, an AC current as small as 6 ma through the body can begin to affect muscle control It is generally agreed that 10 ma of AC current flowing through the body (0.01 amperes) is the threshold at which the current could be considered potentially lethal 33

34 US Dept. of Labor: OSHA "How Electrical Current Affects the Human Body" eleccurrent.html 34

35 Mechanism Typical AC Current Loss of arm/leg muscle control: Average female 10 ma Loss of arm/leg muscle control: Average male Paralysis of breathing muscles Heart fibrillation 16 ma 20 ma 100 ma "Conduction of Electrical Current to and Through the Human Body: A Review" Richard M Fish, PhD, MD, FACEP and Leslie A Geddes, MS, PhD, DSc, Eplasty, v9(2009) 35

36 By way of comparison One 60 watt, 120 volt incandescent light bulb draws 500 milliamperes of current 50 times more than the 10 ma that can paralyze an individual in the water 36

37 What about pets and other critters? 37

38 Animals are not immune to the effects of these water-borne currents ESD has claimed family pets that have entered these charged waters and Individuals have fallen victim to ESD when entering the water in an attempt to rescue their pets Example Irrigation canal deaths 38

39 A Monumental ESD Tragedy Friday Aug 31, 2012 Track coach [woman], two men [one a relative], 1 dog [family pet] electrocuted in Idaho irrigation canal Another family member attempting a rescue was shocked but survived Police say: "The electrified canal could have killed more" They [canal experts] say it is virtually impossible to know if water is electrified by sight or sound Idaho Power shut off the power in the area so rescuers could recover the bodies 39

40 Solar Powered Boat Lift 40

41 Direct Current (DC) is generally not a concern, although it can be a fire or burn hazard under certain conditions It takes from 2 to 5 times as much direct current (DC) to cause the same bodily effect as alternating current (AC) 12 and 24 volt DC systems are not able to produce the water-borne currents or voltage gradients necessary to create an ESD hazard 41

42 Remember: An in-the-water shock hazard can exist wherever shore-powered AC electrical equipment is located in the water, over the water, or adjacent to the water regardless of its function 42

43 Water Leakage Currents 43

44 We know a whole lot more about ESD, water-borne leakage currents and voltage gradients thanks to the extensive and thorough investigative work of Capt. David Rifkin (USN, Ret) and James D. Shafer 44

45 This significant and ground-breaking work by David Rifkin and James Shafer, funded by the US Coast Guard, has provided us with a wealth of data on In- Water Shock Hazards and ESD David Rifkin's research is ongoing and this 150+ page work is one that your presenter references often 45

46 Available at 46

47 Kevin Ritz is a major and long-time contributor to ESD awareness, research and prevention. He lost his son of 8 years, Lucas Ritz, in 1999 as the result of Electric Shock Drowning 47

48 The research by David Rifkin and James Shafer has shown that ESD is a fresh water phenomenon This is due principally to the much lower conductivity (much higher resistance) of fresh water The greater part of the in-water current will flow through the human body with a lesser amount flowing around it 48

49 Current Source Electric Shock Drowning Current Source Fresh Water Water Current Body Current Water Current Voltage Gradient 6 Ft Body Voltage current Gradient is large = 23.8 relative Volts to --- water Very current Lethal 49

50 Causes of Water Leakage Currents 50

51 To establish dangerous levels of leakage current flow in the water and thus produce the resulting lethal voltage gradients two conditions must be met 51

52 First There must be some form of electrical fault (hot to ground) at some point in the AC system (AC powered wiring or equipment) This will be a low level fault current as opposed to the high level of current that occurs as the result of a short circuit The low level fault current is not enough to trip a circuit breaker so it remains continuous and undetected 52

53 Second There must be a failure in the shore power bonding (grounding) system the equipment bonding/grounding path Total failure (open circuit) Very seriously degraded wiring or connection 53

54 When these two conditions exist at the same time, any underwater metals which are no longer bonded back to the AC source become energized to lethal voltage levels The difference in voltage between these energized metals and the power source ground establishes dangerous currents and voltage gradients in the water 54

55 A person finding themselves in this "charged" water can experience a dangerous AC current passing through their body When this current is high enough, nominally in the range of 10 or more milliamps (that's thousandths of an ampere), paralysis is likely to occur, resulting in the inability to remain afloat, followed by drowning 55

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59 Invitation to an ESD Incident 59

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62 One of the 'HOT' conductors 62

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69 Which is why Harbor Cove Marina, Duluth, MN 69

70 NO SWIMMING OFF OF BOATS OR DOCKS Minnetonka Power Squadron Island Facility, Lake Minnetonka 70

71 When Is It "Safe" to Go Into the Water? 71

72 Safe is defined in Webster's 1828 Dictionary as 1. Free from danger of any kind 2. Free from hurt, injury or damage 5. Placed beyond the power of doing harm 72

73 When is it "safe" to? Careful consideration should be given to any use of the word "safe" when working or playing with or near electrically connected equipment that is in, on or near the water 73

74 The term "safe" to enter the water is risky in itself and should never be used where and when shore power is installed and used, or in the context of water leakage currents Example BoatUS Article 74

75 The term "degree of risk" would be more suitable and excludes any inference that somehow absolute safety is guaranteed 75

76 So when is the risk of ESD "very low"? Opinions vary somewhat, but there is general agreement among experts that a minimum distance of between 150 feet and 300 feet from active AC electrical systems would reduce the danger of ESD to "very low risk" (and therefore acceptable?) levels for recreational activities 76

77 It could be considered "very low risk" to enter the water (for inspection, maintenance and repair purposes) where ALL nearby shore power is switched off AT THE POWER SOURCE This would include securing ALL nearby on-board generators and inverters 77

78 What about someone who falls into the water inadvertently (or is just plain careless regarding their well-being)? There are some visual checks and electrical tests that can be performed on a regular basis to reduce the risk of inwater shock for these individuals 78

79 It is never "safe" to enter the water in the vicinity of shore powered watercraft or equipment for any reason EVER! while any nearby circuits are energized! 79

80 Checking the Shore System Wiring 80

81 When checking the shore system at the dock outlet, there is considerably more to it than just checking for voltage and polarity 81

82 More information is required which means more sophisticated testing is required. 82

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84 Checking for Leakage Current 84

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86 Hioki 3283 Excellent for ESD work True RMS Very accurate Reads down to 0.01 ma Cost is

87 Prevention 87

88 NO SWIMMING OR WADING DO NOT ENTER THE WATER RISK OF ELECTRIC SHOCK Signage 88

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90 Ground Fault Protection 90

91 Ground Fault Protection Class A GFCI Receptacle (5 ma Trip) 91

92 Ground Fault Protection Class A GFCI Breaker (5 ma Trip) 92

93 Ground fault (GFCI protection required for 125V, 15 and 20 amp receptacle outlets: Swimming Pools (1971) Located Outdoors (1971) ** Bathrooms (1973) Garages (1978) Spas and Hot Tubs incl hardwired (1981) Boat Houses (1987) ** Boat Hoists incl hardwired (2005) ** 93

94 Ground Fault Protection Disconnect Switch at Accessible Location 94

95 EPO Switch for Marinas? 95

96 Codes and Standards 96

97 Insure Compliance with Codes and Standards NFPA 70 National Electrical Code Article 555 Marinas and Boatyards Mandatory Compliance Required in Minnesota Marina Power Shore Cord 97

98 ARTICLE 555 Marinas and Boatyards [2014 NEC] Scope. This article covers the installation of wiring and equipment in the areas comprising fixed or floating piers, wharves, docks, and other areas in marinas, boatyards, boat basins, boathouses, yacht clubs, boat condominiums, docking facilities associated with residential condominiums, any multiple docking facility, or similar occupancies, and facilities that are used, or intended for use, for the purpose of repair, berthing, launching, storage, or fueling of small craft and the moorage of floating buildings. Private, noncommercial docking facilities constructed or occupied for the use of the owner or residents of the associated singlefamily dwelling are not covered by this article. 98

99 ARTICLE 555 Marinas and Boatyards Scope. This article covers the installation of wiring and equipment in the areas comprising fixed or floating piers, wharves, docks, and other areas in marinas, boatyards, boat basins, boathouses, yacht clubs, boat condominiums, docking facilities associated with one-family dwellings, two-family dwellings, multifamily dwellings, and residential condominiums, any multiple docking facility, or similar occupancies, and facilities that are used, or intended for use, for the purpose of repair, berthing, launching, storage, or fueling of small craft and the moorage of floating buildings. Proposed change in scope for inclusion in 2017 NEC 99

100 Typical ESD Event and Response 100

101 Typical ESD Scenario Victim enters the electrically charged water becomes partially or totally disabled Victim may or may not remain conscious Victim may not remain on surface Victim may or may not call for help Victim's situation can worsen when seeking a "safe haven" (moves toward rather than away from the source) 101

102 Recommended Action for ESD Event The victim should, if able, keep arms and legs close to the body (this action reduces exposure to the voltage gradient) should, if able and possible, move back in the direction from which they came or otherwise, move away from the presumed current source 102

103 Recommended Action for ESD Event First responders/rescuers/bystanders should, if at all possible, switch off all dock electrical power at the source must fight the instinct to enter the water many well-meaning rescuers have died trying to help ESD victims must remember always to Reach Throw Row But Don't Go (into the water) 103

104 Recommended Action for ESD Event First responders/rescuers/bystanders should throw life ring or other flotation device, etc. to a conscious and able victim should not throw a line to the victim and then pull the victim closer to the current source Should push the victim away from the presumed source with an insulated pole 104

105 Recommended Action for ESD Event First responders/rescuers/bystanders should attempt first aid/cpr where the victim can be safely removed from the water should call for help immediately Dial 911 or call on VHF Channel 16 as appropriate should know that there is currently no known portable test device available to quickly detect a hazardous condition in the water 105

106 Training Recommended ESD response training should be provided for the following (at a minimum) Law Enforcement Firefighters Emergency Medical Technicians Marina Staff Others? 106

107 In Summary 107

108 Remember: An in-the-water shock hazard can exist wherever shore-powered AC electrical equipment is located in the water, over the water, or adjacent to the water 108

109 The Cardinal Rule: Do not enter the water in the vicinity of shore powered watercraft or equipment for any reason EVER! while any nearby electrical equipment or circuits are energized! 109

110 Please Take a Brochure Take One for a Friend or Neighbor 110

111 More Information 111

112 ELECTRIC SHOCK DROWNING PREVENTION ASSOCIATION 112

113 Quality Marine Services, LLC 113

114 ELECTRIC SHOCK DROWNING RESOURCE CENTER 114

115 QUESTIONS? 115

116 Thank You 116

117 Edward "Ed" Lethert Electric Shock Drowning Safety Specialist New Hope, MN 117