Electrocution possible in water even with "low voltage"

[Joethemechanic]

You are misreading the or taking the OP too literally. 24V is not the source voltage. Nobody drowns because they fall into the water holding a battery, but it only takes a voltage gradient of around 10V from a faulty wire or stray voltage around a fresh water dock or swimming pool to paralyze someone and they curl up and sink in the water and don't come up.

I was just going by this statement.

In HVAC school I was taught that 24VAC was "safe"; it was low voltage.

And yes in that context 24 volts is safe. Unless you are talking about fires, and I've seen that happen with just a few volts

 

[Joethemechanic]

This might be a "Hold my beer" moment, and I definitely don't recommend trying it, but

 

[ActionDave]

I was just going by this statement.

In HVAC school I was taught that 24VAC was "safe"; it was low voltage

I understand what you are saying. The part that I focused on was this....

And, I have been reading ELECTRIC SHOCK DROWNINGS by Shafer and Rifkin from Mike's website.

There have been too many deaths in lakes. We've got the NEC/NFPA Industrial Complex adding GFCIs to drinking fountains and vending machines where nobody dies, and expanding AFCIs even though everybody knows they are an outright fraud, but they can't get their act together enough to address the most deadly electrical problem out there today?

Stepping off my soap box. Carry on.

 

[don_resqcapt19]

I understand what you are saying. The part that I focused on was this....

There have been too many deaths in lakes. We've got the NEC/NFPA Industrial Complex adding GFCIs to drinking fountains and vending machines where nobody dies, and expanding AFCIs even though everybody knows they are an outright fraud, but they can't get their act together enough to address the most deadly electrical problem out there today?

Stepping off my soap box. Carry on.

What about the required 30 mA protection for all new shore power outlets? Because of the area of the water around some energized part, the 30 mA device will trip the circuit before someone gets hurt, unless the person is very close to the faulted object when the ground fault occurs.

However that only addresses faulty equipment and not any issue caused by elevated neutral to earth voltage.

 

[macmikeman]

So, having read all the above discussion on low voltage electrical hazards , it is appropriate to assume salt water swimming pools are inherently safer than fresh water swimming pools , given that all other electrical hazards are properly mitigated for purposes of this discussion?

 

[ActionDave]

What about the required 30 mA protection for all new shore power outlets? Because of the area of the water around some energized part, the 30 mA device will trip the circuit before someone gets hurt, unless the person is very close to the faulted object when the ground fault occurs.

However that only addresses faulty equipment and not any issue caused by elevated neutral to earth voltage.

I've been in favor of 30mA or some level of GFEP level protection for almost every type of branch circuit for a long time. It was you who said that there is no system in place to make sure that GFEP actually works.

Neutral to earth voltage is an issue that is outside the NEC scope but I doubt that it is the cause of the drowning deaths every year at recreational lakes.

 

[winnie]

Neutral to earth voltage is an issue that is outside the NEC scope but I doubt that it is the cause of the drowning deaths every year at recreational lakes.

My question is: elevated neutral voltage (caused by distribution systems or other regional electrical systems) can cause hazards in water, and local system faults can cause hazards. But do any of us have information about the prevalence of one risk vs the other?

We recently had a thread where someone was experiencing shocks from grounded metal, and everyone (including me) jumped on the elevated neutral voltage bandwagon...but the problem was a neighbor's faulted well pump with a non-bonded casing....

Jon

 

[drcampbell]

So, having read all the above discussion on low voltage electrical hazards , it is appropriate to assume salt water swimming pools are inherently safer than fresh water swimming pools , given that all other electrical hazards are properly mitigated for purposes of this discussion?

I suspect that salt-water pools are safer for fully-immersed people, and less safe for people with their feet in the water and their hand touching something else. I have not field-verified this.

I don't think it's appropriate to be making the comparison. Assuring safety should be the goal, not quibbling over different hazards.

 

[don_resqcapt19]

I've been in favor of 30mA or some level of GFEP level protection for almost every type of branch circuit for a long time. It was you who said that there is no system in place to make sure that GFEP actually works.

Neutral to earth voltage is an issue that is outside the NEC scope but I doubt that it is the cause of the drowning deaths every year at recreational lakes.

There is no standard on the time to trip for GFPE.
Most of the ESDs have been faulty equipment, but a few have been NEV.

 

[ericsarratt]

This might be a "Hold my beer" moment, and I definitely don't recommend trying it, but

This is just disturbing.

 

[ericsarratt]

expanding AFCIs even though everybody knows they are an outright fraud

How so? I'm interested.

I once heard a building/electrical/plumbing inspector call GFCI's a scam; he said it was pushed by the industry into code just to make money. I respect his opinion, but I don't know enough about this yet to make up my own mind.

Thank you all for your comments.

 

[roger]

How so? I'm interested.

GFCI operation is easily proved, AFCI not so.

 

[kwired]

How so? I'm interested.

I once heard a building/electrical/plumbing inspector call GFCI's a scam; he said it was pushed by the industry into code just to make money. I respect his opinion, but I don't know enough about this yet to make up my own mind.

Thank you all for your comments.

GFCI itself is not a scam. However in more recent code editions it maybe has been pushed by the industry into more situations requiring GFCI protection with little justification for doing so. Some the situations that now require a three pole GFCI are mostly "because we can" rather than backed up by shock/electrocution statistics from the past, unlike some the earliest GFCI requirements that were mostly all driven by actual incident statistics. Then you have the dwelling unit dishwasher GFCI requirement - initially put in because of something that should have been taken up by consumer product safety commission and some recalls should have been forced to fix a problem, instead, they figured out a GFCI would very likely detect said problem and trip when that problem arises.

 

[slaffan]

Hi everyone, I just came across this forum while searching for help for a situation in my favorite lake I like to swim in. Last year I started noticing a tingly sensation in my fingers while swimming. As the summer went on it got stronger, so much so that it was uncomfortable to be in the water. I tried to make the local government aware, but it seems they are trying to pass it off as swimmer's itch, signs at beach now. It is not, my mom had one of those immersible water heaters and I stuck my hand in to see if the water was warming up. Same tingly feeling. Any suggestions?

 

[drcampbell]

Electric shock drowning - Wikipedia

en.wikipedia.org

 

[a.bisnath]

Just want to thank everone on this thread, I had never known about or came across this situation, worked on piers and offshore for many years with impressed current cathodic protection . Thumbs up.

 

[kwired]

Hi everyone, I just came across this forum while searching for help for a situation in my favorite lake I like to swim in. Last year I started noticing a tingly sensation in my fingers while swimming. As the summer went on it got stronger, so much so that it was uncomfortable to be in the water. I tried to make the local government aware, but it seems they are trying to pass it off as swimmer's itch, signs at beach now. It is not, my mom had one of those immersible water heaters and I stuck my hand in to see if the water was warming up. Same tingly feeling. Any suggestions?

Do not swim near docks, especially if they have metallic paths of any kind back to another structure. Without getting too technical, any "stray voltage" on the grounded conductor serving such structure is potentially extended via those metallic pathways to the dock. Might only be a couple volts, but that is enough to be problematic.