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    #16
    Originally posted by don_resqcapt19 View Post
    There is a voltage gradient in the water as a result of the current flow. The human becomes part of the current path.

    The wet human body is a parallel path within the water and the resistance of the wet human is less than the resistance of the water, so the parallel resistances, the water and the human, act as a current divider with the most current flowing on the human.
    And the extent to which the current causes muscle or heart problems will depend on how the body is oriented with respect to the voltage gradient.
    Turning to head towards the pool edge or shore or going from a standing to a swimming position may make the shock worse or make it better.

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      #17
      I'm just trying to figure out in theory, of a story I read where a 120 volt line came into contact with a public pool that had roughly 20 people in the pool at the time of the electrical contact with the water. There was only 1 death as a lifeguard when to jump into the pool and touched the metal ladder rail (which I understand because it was grounded), but all the other people survived and all claimed tingling all over their skin but kept complete muscle control. I find it hard to believe that (0.05)amps or higher didnt cross anyone else's heart if the current truly went thru them and not just around them??

      Has it ever been proven that chlorinated or salt water is much less or more resistive vs a human's body with all the water and electrolytes we have, just curious??

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        #18
        Originally posted by Lmeagles36 View Post
        I'm just trying to figure out in theory, of a story I read where a 120 volt line came into contact with a public pool that had roughly 20 people in the pool at the time of the electrical contact with the water. There was only 1 death as a lifeguard when to jump into the pool and touched the metal ladder rail (which I understand because it was grounded), but all the other people survived and all claimed tingling all over their skin but kept complete muscle control. I find it hard to believe that (0.05)amps or higher didnt cross anyone else's heart if the current truly went thru them and not just around them??

        Has it ever been proven that chlorinated or salt water is much less or more resistive vs a human's body with all the water and electrolytes we have, just curious??
        As Gold said in post 16 there are a lot of factors that enter into that issue.

        As far as the water, salt water is much more conductive, and injury or death in salt water from electrical in contact with the water is rare.
        Don, Illinois
        (All code citations are 2017 unless otherwise noted)

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          #19
          New Jersey did not adopt 690.47(D).
          Rick Napier
          Inspector and Instructor

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            #20
            water that has ions to allow electrons to move more freely is a better conductor. electric wire in pure H2O is not a hazard, etc.

            as said previously, its not the voltage that will kill you, its the small amps that will. you need the correct volts to allow that small amps.

            if there is a shock between water and metal ladder then that would indicate inadequate bonding. but remember, bonding only works well if the water conducts well. example, if it were pure H2O and you were holding the hot leg of 120vac in the water, the water would not conduct, but when you grab the ladder that would be an issue. with a pure infinite ohms bonding system (infinite ohms) you would not get shocked, but NEC requires bonding to be attached to pool pump (or bonding lug of the system) which is typically tied to service GND. in this case you'll get a good zap and hopefully GFI trips, if a faulty GFI then hopefully its not fatal, but can be. how many folks actually press the TEST button on gfi's on a regular basis ??? i do my own panel about once per year, last year one was faulty, it did the infamous shorting hum with smoke, it was a faulty gfi for whatever reason. breaker was sent back to manufacturer for their analysis, they likely just tossed it in the trash. security on supply chains is in fact a major issue these days, the breakers you use that say "Eaton" on them may be knock-off's, etc.

            in my view, a pure infinite ohms bonding system is the best for safety, its just not achievable. bond it all, add some earth rods, tie/bond it all back to service gnd (i do not rely on pump frame to be service gnd).
            Last edited by FionaZuppa; 07-19-16, 11:17 AM.

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              #21
              Originally posted by FionaZuppa View Post
              in my view, a pure infinite ohms bonding system is the best for safety,
              I don't know if I would call that a view as much as I would call it a fact.

              its just not achievable.
              Exactly.

              bond it all,
              For sure


              add some earth rods,
              Now you suggesting grounding myths and voodoo. Sprinkling a property with extra ground rods will not increase the performance of the equal potential bonding of a pool.


              tie/bond it all back to service gnd (i do not rely on pump frame to be service gnd).
              This strongly suggests you do not grasp the objective of the equal potential bonding at a pool. I would also say your statement adds to grounding myths.

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                #22
                Originally posted by iwire View Post


                This strongly suggests you do not grasp the objective of the equal potential bonding at a pool. I would also say your statement adds to grounding myths.
                bonding to a pump frame does what exactly, in its entirety?
                i fully understand the equi-potential "concept", i just dont like the option of being energized to say 240vac even if its all at 240vac, etc. nec suggests equi-pot to reduce some risk, i like that risk to be reduced further.

                did you watch the MH video http://forums.mikeholt.com/showthread.php?t=177882

                he lifts the N, the earth rods can reduce the voltage found on other metal parts of the structure, which reduces safety hazard.
                Last edited by FionaZuppa; 07-19-16, 01:17 PM.

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