electric shock drowning - lake...

07/22/2015 Ed Lethert

Electric Shock

Drowning


Electric Shock Drowning

Thanks to

Gary Hughes

Greg Nybeck

LMCD Board

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Edward "Ed" Lethert


Safety Specialist

New Hope, MN

[email protected]

www.electricshockdrowningmn.com

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Background Lakeshore Weekly News Article



Lake Minnetonka Boater

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Member: Minnetonka Power Squadron



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ELECTRIC SHOCK DROWNING

PREVENTION ASSOCIATION



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AWARENESS

PREVENTION



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

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Thanks



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Questions

Questions and comments are welcome

and encouraged immediately following

the presentation

Presenter will also be available after the

meeting to address additional questions



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Thanks to Capt. David Rifkin and Kevin

Ritz for permission to use some of their

material.



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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."



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?

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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")

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This subject material applies directly to

ANY environments where electric circuits

and equipment operate in, on, or near a

body of water

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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

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ESD Victims



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Lost to ESD

Comment: Samantha Chipley Article



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Marcus Colburn, age 21, died as a result of ESD on Father’s Day, June 21st, 2015

Lost to ESD

Comment: Circuit Breaker



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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



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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 post-

mortem as the cause of

the drowning



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Electrical Safety

Around Water



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This goes without saying



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As does this … I hope



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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



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National Electrical Code

90.1 Purpose.

(A) Practical Safeguarding. The purpose

of this Code is the practical safeguarding

of persons and property from hazards

arising from the use of electricity. …

2014 NEC (NFPA 70)



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"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



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Electric Shock

Drowning



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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



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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)



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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



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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



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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



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US Dept. of Labor: OSHA – "How Electrical Current Affects the Human Body"

www.osha.gov/SLTC/etools/construction/electrical_incidents/

eleccurrent.html



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Mechanism Typical AC Current

Loss of arm/leg muscle control:

Average female 10 mA

Loss of arm/leg muscle control:

Average male 16 mA

Paralysis of breathing muscles 20 mA

Heart fibrillation 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)



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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

By way of comparison …



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What about pets and other critters?



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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



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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



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Solar Powered Boat Lift



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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



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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



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Water Leakage

Currents



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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



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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



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Available at www.qualitymarineservices.net



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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



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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



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Water Current

Water Current

Voltage Gradient = 23.8 Volts --- Very Lethal

Voltage Gradient

6 Ft

Fresh Water

Body Current

Curr

ent

Sourc

e

Body current is large relative to water current

Curr

ent

Sourc

e



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Causes of Water

Leakage Currents



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To establish dangerous levels of leakage

current flow in the water—and thus

produce the resulting lethal voltage

gradients—two conditions must be met



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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



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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



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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



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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



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Invitation to an

ESD Incident



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One of the 'HOT' conductors



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Harbor Cove Marina, Duluth, MN

Which is why …



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Minnetonka Power Squadron

Island Facility, Lake Minnetonka

NO SWIMMING

OFF OF BOATS

OR DOCKS



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When Is It "Safe" to

Go Into the Water?



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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



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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



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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



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The term "degree of risk" would be more

suitable and excludes any inference that

somehow absolute safety is guaranteed



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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



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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



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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 in-

water shock for these individuals



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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!



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Checking the

Shore System

Wiring



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When checking the shore system at the dock

outlet, there is considerably more to it than

just checking for voltage and polarity



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More information is required which means

more sophisticated testing is required.



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Checking for

Leakage Current



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Hioki 3283

Excellent for ESD work

True RMS

Very accurate

Reads down to 0.01 mA

Cost is ≈ 350.00



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Prevention



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NO SWIMMING

OR WADING

DO NOT ENTER

THE WATER

RISK OF

ELECTRIC

SHOCK

Signage



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Ground Fault

Protection



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Class A GFCI Receptacle (5 mA Trip)

Ground Fault Protection



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Class A GFCI Breaker (5 mA Trip)




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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) **



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Disconnect Switch at Accessible Location




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EPO Switch for Marinas ?



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Codes and

Standards



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Marina

Power

Shore

Cord

NFPA 70

National Electrical Code

Article 555

Marinas and Boatyards

Mandatory Compliance

Required in Minnesota

Insure Compliance with Codes and Standards



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ARTICLE 555 — Marinas and Boatyards [2014 NEC]

555.1 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 single-

family dwelling are not covered by this article.



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ARTICLE 555 — Marinas and Boatyards

555.1 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



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Typical ESD Event

and Response



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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)



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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



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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)



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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



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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



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Training Recommended

ESD response training should be provided

for the following (at a minimum)

Law Enforcement

Firefighters

Emergency Medical Technicians

Marina Staff

Others?



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In Summary



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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



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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!



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Please Take

a Brochure

Take One for

a Friend or

Neighbor



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More Information



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PREVENTION ASSOCIATION

www.electricshockdrowning.org/



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Quality Marine Services, LLC

www.qualitymarineservices.net



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RESOURCE CENTER

www.boatus.com/seaworthy/ESD.asp



QUESTIONS ?

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Thank You

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Edward "Ed" Lethert


Safety Specialist

New Hope, MN

[email protected]

www.electricshockdrowningmn.com

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