Electric Shock Drowning

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1 Electric Shock Drowning Your logo here Electric Shock Drowning Navigating Changing Code Requirements Slide 1

2 Electric Shock Drowning - Safety and Maintenance 2

3 What is Electric Shock Drowning? Electric Shock Drowning occurs when faulty wiring on a boat or in a marina causes underwater metals to become energized. Examples of underwater metals that could become energized Boat props, dock frames, ladders, etc This creates an electrical field in the water The magnitude and intensity of the electrical field is determined by how much current is being leaked into the water.

4 What is Electric Shock Drowning? A swimmer enters the electrical field and completes the electrical circuit to ground. The swimmer becomes a target for the electrical current leakage because the human body is a better conductor of electricity than fresh water Fresh water is close to 70 times more resistive than salt water. This makes electric current leakage in fresh water marinas a major concern. Depending on the amount of current in the water and a swimmers location relative to the electrical field, a person may experience effects ranging from a slight tingle, to complete loss of muscle control, to ventricular fibrillation.

5 Underwater Electrical Field 50mA of Leakage 20mA of Leakage 5mA of Leakage

6 Electric Shock in Freshwater Medical Facts Current Effects 1 ma to 8 ma Tingle, sensation of shock, not painful, muscle control not lost 8 ma to 15 ma Painful shock, muscle control not lost Current (Amps) Not Voltage Light Bulb 100 ma 15 ma to 20 ma Pain shock, muscle control is lost, paralysis / inability to swim occurs, labored breathing 50 ma to 100 ma Ventricular Fibrillation possible 100 ma to 200 ma Ventricular Fibrillation occurs 200+ ma Burn marks may appear, chest muscles clamp heart

Salt Water Environment Electricity is transported around the swimmer by the salt Fresh

7 Path of Least Resistance Electricity will always look to return to its power source through the path of least resistance. Salt is a great conductor of electricity. Salt Water Environment Electricity is transported around the swimmer by the salt Fresh Water Environment The swimmer is the path of least resistance due to the salt content of the human body

8 Signs of Electric Shocking Drowning Potential Often leaves no bodily clues to suggest anything but simple drowning due to alcohol intoxication or heart attack. No signs of burning due to the victim being submerged in water no signs of electrocution. Often classified as electrical shock due to evidence of great distress, multiple deaths Signs of a Potential Problem: Tingling sensation reported by anyone swimming in the marina. Excessive damage to metal boat parts in the water props, etc

9 Ground-Fault Regulations and Requirements

10 National Electrical Code Ground-Fault Protection (2014) 2014 National Electrical Code The main overcurrent protective device that feeds the marina shall have ground fault protection not exceeding 100mA. Ground-fault protection of each individual circuit breaker or feeder circuit shall be permitted as a suitable alternative. Overcurrent protection device the device that disrupts power to a circuit or piece of electrical equipment in the event of an electrical problem. Examples include circuit breakers and fuses. Circuit breakers are the most common form of ground-fault protection devices.

11 National Electrical Code Ground-Fault Protection (2017) NEW 2017 National Electrical Code The main overcurrent protective device that feeds the marina shall have ground fault protection not exceeding 30mA. Groundfault protection of each individual circuit breaker or feeder circuit shall be permitted as a suitable alternative.

12 National Electrical Code 553 Floating Buildings The same code applies for floating buildings such as ship stores, bathrooms, and restaurants.

13 Important Note on NEC Adoption Compliance with the most up to date NEC and NFPA codes are only required for new construction or modification that changes the fit, form, or function of a marina. Basic maintenance changing a light bulb, receptacle, or circuit breaker does not require drastic upgrades to the entire electrical system. Some states or municipalities are requiring immediate compliance. Most are not. Check with the local AHJ for code requirements.

14 Equipment and Protection Locations Examination Points Protection Equipment Protection Locations Code Compliance? Protection of Human Life? Effects of Outage Costs Retrofitability Other Pros / Cons

15 Available Equipment

16 Ground-Fault Monitors Install a ground fault monitoring system in the marina. Usually consist of a control module and current transformer(s). Wires are run through the current transformer(s) and the electrical cycle is measured. Multiple models Single Source Monitoring One monitor for one major power source Multiple Source Monitoring One monitor for multiple power sources

Single-Source Monitors Design Characteristic Cost Leakage Grouping Effect Ease of Detecting the Cause or Causes of Leakage Sources Effect of Monitoring Method Low Single CT units are relatively

17 Single-Source Monitors Design Characteristic Cost Leakage Grouping Effect Ease of Detecting the Cause or Causes of Leakage Sources Effect of Monitoring Method Low Single CT units are relatively inexpensive and can be added to existing equipment. High more devices monitored by a single CT produce a high likelihood of leakage grouping. Difficult pinpointing the device or devices producing the leakage can be problematic due to the number of devices on one monitor

Multi-Source Monitors Design Characteristic Cost Leakage Grouping Effect Ease of Detecting the Cause or Causes of Leakage Sources Effect of Monitoring Method High Multiple CT units can be expensive

18 Multi-Source Monitors Design Characteristic Cost Leakage Grouping Effect Ease of Detecting the Cause or Causes of Leakage Sources Effect of Monitoring Method High Multiple CT units can be expensive due to the number of CTs required for monitoring. Low - each circuit is monitored by a single CT. Fewer vessels monitored on one CT limits the grouping effect. Easy if an alarm is triggered, the piece of equipment it is monitoring is experiencing a problem.

19 Ground-Fault Circuit Breakers Installing ground fault circuit breakers in all pedestals can be expensive and lead to customer renovations. Customer renovations customers frustrated by circuit breakers that constantly trip bypass protection devices. It is important to educate boat owners of the potential hazards associated with work performed by untrained professionals. Nuisance tripping common phrase used by customers to deflect blame for faulty boat wiring and / or repairs. If a circuit breaker is in good working condition and trips, there is a problem present.

20 Types of Ground-Fault Breakers Different Types of Ground Fault Circuit Breakers 5mA or 6mA People Protection 30mA Equipment Protection REMINDER: Current versions of the NEC Code require 100mA protection somewhere within the electrical system for all new installations. REMINDER: 15mA can cause serious injury Current Effects 15 ma to 20 ma Pain shock, muscle control is lost, paralysis / inability to swim occurs, labored breathing

21 Ground-Fault Breaker Manufacturer s Warning

22 Customer Renovations

23 Protection Locations Case Study

24 Case Study Dock Layout Design Criteria Two Docks 20 Slips Per Dock Power at Head of Each Dock Power Pedestals Multiple Pedestals per Circuit

25 Protection at the Utility Entrance / Main Power Source Circuit breaker protection (using a ground fault monitor) can be located where the incoming power enters the facility from the utility company. While this is a very economical solution, it may be difficult to pinpoint the exact cause or causes of the current leakage.

26 Protection at the Utility Entrance / Main Power Source

27 Protection at the Utility Entrance / Main Power Source Location Utility Entrance or Main Power Source Method Ground-Fault Monitor tied to Shunt-Trip Circuit Breaker Outage % 100% (40 of 40 slips) Approximate Cost $50 / slip

28 Protection on Main Breakers or Feeders to Each Dock Circuit breaker protection can be located at the head (or on the main circuit breaker) feeding each dock within a disconnect or distribution panel. Usually requires a ground fault monitor to reach an acceptable 100mA threshold. Identifying the cause or causes of the leakage depends on how the system is wired.

29 Protection on Main Breakers or Feeders to Each Dock

30 Protection on Main Breakers or Feeders to Each Dock Location Main Feeder for Each Dock in MDP Method Multi-CT Ground-Fault Monitor tied to Shunt- Trip Circuit Breakers Outage % 50% (20 of 40 slips) Approximate Cost $80 / slip

31 Protection on Each Dock Circuit Circuit breaker protection can be located on each circuit on the dock within a distribution panel or through a ground fault monitoring system with shunt trip circuit breakers. While this is a more costly solution, it is relatively easy to identify the cause or causes of the leakage.

32 Protection on Each Dock Circuit

33 Protection on Each Dock Circuit Location Each Circuit Breaker for Each Panel on the Dock Method Multi-CT Ground-Fault Monitor tied to Shunt- Trip Circuit Breakers Outage % 15% (7 of 40 slips) Approximate Cost $295 / slip

34 Protection for Each Receptacle Circuit breaker protection can be located at the head (or on the main circuit breaker) feeding each dock within a disconnect or distribution panel. Usually requires a ground fault monitor to reach an acceptable threshold. Identifying the cause or causes of the leakage depends on how the system is wired.

35 Protection for Each Receptacle

36 Protection for Each Receptacle Location Each Circuit Breaker in Each Power Pedestal Method Ground-Fault Circuit Breakers or Monitors w/ Shunt-Trip Breakers Outage % 2.5% (1 of 40 slips) Approximate Cost $325 - $520 / slip

37 Protection for Each Receptacle $325 People Protection (5 or 6mA) $520 Equipment Protection (30mA) Current 15 ma to 20 ma Effects Pain shock, muscle control is lost, paralysis / inability to swim occurs, labored breathing

38 NEC 2017 Required Signage Signage. Permanent safety signs shall be installed to give notice of electrical shock hazard risks to persons using or swimming near a boat docks or marina and shall comply with all of the following: (2) The signs shall be clearly visible from all approaches to a marina or boatyard facility. (3) The signs shall state WARNING POTENTIAL SHOCK HAZARD ELECTRICAL CURRENTS MAY BE PRESENT IN WATER.

39 Signs of Potential Problems

40 Signs of Potential Problems

41 Signs of Potential Problems

42 Signs of Potential Problems

43 Signs of Potential Problems

44 Signs of Potential Problems

45 Signs of Potential Problems

46 Signs of Potential Problems

Good References for Marina Electrical Safety NFPA 303 Fire Protection Standards for Marinas and Boatyards National Electrical Code Handbook Article 555 Marinas and

47 Good References for Marina Electrical Safety NFPA 303 Fire Protection Standards for Marinas and Boatyards National Electrical Code Handbook Article 555 Marinas and Boatyards ACSE 50 Planning and Design Guidelines for Small Craft Harbors American Boat and Yacht Council Electrical Safety Foundation Intl. ADA Local Electrical Authorities 47

48 Good References for Marina Electrical Safety To get a copy Ekretsch@MarinaAssociation.org 48

49 What is AMI doing to address electric code issue? 2020 National Electric Code Update Submitted a Public Input Proposal (with VMTA) at the start of the 2020 update process Continuing to monitor process, will work with VMTA and other affiliates to respond during comment periods Next comment period is August 2018 Representation on National Electric Code, Code Making Panels

50 What is AMI doing to address electric code issue? 2017 National Electric Code Update Will provide resources, information, and support to Affiliate associations who want to work on local level to amend the 2017 code. Continuing to monitor and respond to TIA proposals Tentative Interim Amendments Investigating options to propose a TIA with industry support, developed by industry experts.

51 Questions? Chris Dolan Marina Electrical Equipment (855) Phone (757) Fax (757) Mobile We now welcome any questions you have on today s topic.

GROUND FAULT PROTECTION METHODS & 2017 National Electric Code

GROUND FAULT PROTECTION METHODS 2014 & 2017 National Electric Code Ground Fault Protection Methods A Ground Fault Circuit Interrupter, or GFCI, is a device that functions to de-energize a circuit when