help do batteries in water= danger?

Thread Starter

cbtaylor

Joined Feb 3, 2004
1
Hello all,

I am a clueless visitor to the world of electronics. But I have an urgent question about the risk of an AAA battery if dropped into a swimming pool

Because of a damaged knee, I have to do serious exercise in a large indoor swimming pool each day, wearing foam belts to keep me afloat, never getting my head wet, a good third of me always above the water line. To past the time, I have begun wearing a nifty Sony headset radio powered by one tiny AAA battery and listen to good music. Lately, the pool manager told me that there have been worried questions by others who use the pool when I do--ie: what if the earphones fell off into the water, would they get a shock or worse? I've been told I need to document the fact that this will not happen if indeed there is no threat. It seems to me impossible that this tiny battery IS a threat, but I need your help! Is there a textbook/article/anything out there that I can xerox to show this pool manager that doom does not await the other users of the pool in the very unlikely event that the headset does slip off my head?

I would be terrifically grateful for any and all help on this.

meanwhile, much cheer....
 

Dave

Joined Nov 17, 2003
6,969
You are probably best getting in contact with a professional body such as the IEE, who retain information on a wide range of acceptable practices, with respect to electrical equipment.
 

Battousai

Joined Nov 14, 2003
141
I highly doubt one triple A battery in water will shock anybody in the pool. To explain it, I guess you should consider the conductivity of the water, which I'm assuming is filled with chlorine as well. The potential of a triple A battery is around a few volts? Then just use ohm's law to determine the current through the water, it's going to be very small, negligible.

Hope you get well soon.
 

impetey

Joined Jan 10, 2004
11
The potential (voltage) across a "transistor" battery you know the rectangular shaped jobbies is 9 v. I used to check fully charged ones for remaining life by touching them to the tip of my tongue!! Oh foolish youth :p it gives a slight tingly sensation. This is direct contact to wet sensitive flesh with 9 Volts. A AAA battery fully charged is 1.5 volts and the poles (contacts,terminals) are at opposing ends (you'd have to pop the whole battery in your mouth to test as I did in my troubled past). The minimal power available in this battery and hence the "deadly" current being what it is, I think your panicky lifeguard and those who use the pool can sleep soundly at night knowing that they'd get more of a shock wearing nylon socks, schlepping across a shag rug and touching something grounded in the house. No need to contact IEEE on this one!!! ;)
 

guitar333

Joined Feb 4, 2004
5
Yep, that will do nothing. When the human body is wet it lower the bodies resistantce to current (or voltage which will create current). So touch both ends of a AAA battery.........nothing? Get your fingers wet and touch both ends of that battery......still nothing. It is no different in a pool.
 

Dave

Joined Nov 17, 2003
6,969
While I agree that going to the IEE or such body is very extreme, remember what he asked for:

Is there a textbook/article/anything out there that I can xerox to show this pool manager that doom does not await the other users of the pool in the very unlikely event that the headset does slip off my head?

Unless your lifeguard will accept the posts from this forum! :D
 

eldon

Joined Jan 24, 2004
14
I did a bit of a search for something quotable and found this website used to explain how to teach students about electricity.


http://www.culverco.com/interactive/Pages/...d/teachgde.html


Of note is the following quote from about 1/3 of the way down the page.

"It is important to emphasize that even though Ben Franklin was not seriously hurt in the example, electricity is always dangerous. Electricity's unpredictability adds to its danger.

"Again, you may want to remind students that they're able to work with these batteries and wires because the voltage is minimal (1.5 V per D cell battery)."

Also note that:
In industrial and house wiring, a totally different standard applies to any wiring carrying low voltage control signals IE doorbell and thermostat wiring since these voltage levels posse minimal threat unless there is a direct short circuit across the source.

You might just try an experment and measure the voltage across a 1 ohm resistor directly across the AAA battery thus giving you the total current capacity of the battery under extreem load conditions. I = E/R since R = 1 then I = E.
 

Dave

Joined Nov 17, 2003
6,969
Heres the ful quote from your second extract:

Even good insulators may conduct electricity when wet.

Teams will need to add a lot of salt to their water in order for electric current to flow. The voltage of the battery is so low that additional particles must be added to make the water more conductive. It is the impurities in water that make it a good conductor.

Pure water will not conduct electricity. However, pure water is only found in the laboratory. That's why there is so much emphasis on the conductivity of water.

You may want to remind students that they are able to work with these batteries and wires because the voltage is minimal (1.5 V per D cell battery)


Good find :)
 

impetey

Joined Jan 10, 2004
11
The discussion of water purity vis-a-vis conductivity was sure to be addressed by our astute subscribers. The danger from the lost AAA battery may be less from the electrical discharge than from the discharge of potentially harmful chemicals as the battery corrodes resulting in leakage (probably sooner than the electrical life of the battery as it slowly discharges in the agressive, chlorine rich water). Still leaks of other unsavory substances also occur in public pools...probably beyond the control of the lifeguard (or certain swimmers)! ;) Well done to those that followed up on an authoritative citation to help the Poster :)
 

GopherT

Joined Nov 23, 2012
8,009
Please do not reply to a 10-year old thread.
I think he was going for a new record in thread resuscitation! One day, I would like to see the thread started will come back and thank these guys for their 3-, 7- or, in this case, 10-year belated post!

Something like,
CBTaylor: "thank you for your helpful post. I stopped going to that swimming pool when I was 17 because they would not let me use my sony MP3 player. I was just discussing with my wife where we should take our children to swimming lessons. I realized that I can use your information to convince the current pool management that my underwater GoPro camera will not electrocute all of the kids in the pool."
 
Last edited:

ian field

Joined Oct 27, 2012
6,536
Hello all,

I am a clueless visitor to the world of electronics. But I have an urgent question about the risk of an AAA battery if dropped into a swimming pool

Because of a damaged knee, I have to do serious exercise in a large indoor swimming pool each day, wearing foam belts to keep me afloat, never getting my head wet, a good third of me always above the water line. To past the time, I have begun wearing a nifty Sony headset radio powered by one tiny AAA battery and listen to good music. Lately, the pool manager told me that there have been worried questions by others who use the pool when I do--ie: what if the earphones fell off into the water, would they get a shock or worse? I've been told I need to document the fact that this will not happen if indeed there is no threat. It seems to me impossible that this tiny battery IS a threat, but I need your help! Is there a textbook/article/anything out there that I can xerox to show this pool manager that doom does not await the other users of the pool in the very unlikely event that the headset does slip off my head?

I would be terrifically grateful for any and all help on this.

meanwhile, much cheer....
You'd only just feel 1.5V if you applied the terminals to broken skin.

A leaky battery would pollute the water - but you're in the same general direction as a drop in the ocean.
 

#12

Joined Nov 30, 2010
18,224
(Not a serious answer.)
What? 10 years old? I just wallowed a new AAA battery around in my mouth to prove the answer I expected so I could suggest several other damp and closely personal places the pool manager might try. What a waste of time! :mad:

;):D
 
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