In all of the discussions of hair-dryer in a tub scenario, no one has discussed the GFI and how it works. It senses the current in both power leads, and if they are not equal, it trips OFF. Thus it assumes that any current flowing between phase/neutral is good, any current in the phase lead not returning in the neutral is not-good.
Ignoring the physical fact that pure water is an excellent insulator--- dropping the hair dryer in an older home with metal piping will probably result in instant trip-out, since some current will find a path back via the pipes to electrical earth. dropping the hair dryer in a newer home with all plastic piping is probably a more hazardous situation. The GFI will not trip out, and a person may provide a lower impedance path between phase/neutral connections in the dryer than the surrounding water. Our bodies are flooded with a saline solution (blood) and are very conductive once the skin is bypassed. I have done some work in the crawl-space of my daughters' home in Durham NC, and know for certain that the waste/water lines are all plastic. There could be a grounding circuit but I am not aware of it. Naturally the tub & surround are all plastic also. The warnings provided with hair dryers and similar appliances warning against their use in wet areas must be observed. [email protected]
