Say you have one in a basement and the basement floods. I know that it is supposed to “trip” and not provide electricity to whatever is plugged into it, but is it safe to be around itself?
AFAIK, there are live wires connected into the outlet like any other outlet. Wouldn’t those conduct into the water?
Yes, there are live wires behind the box. If the breaker doesn’t trip, they’re still live. The GFCI is to protect things downstream of it (be it your fingers or other outlets), not upstream (the wiring between the outlet and the breaker box).
Now, I always assumed that it was more or less safe to walk around in the water in that situation. The water, I assumed, would create a path to ground. It’s got the actual ground wire just an inch away, it’s got every grounded/bonded metal object it’s in contact with in the basement and it’s got the actual ground (the concrete). And, if that wasn’t going to create a dead short, you’d be at the same potential wandering around down there (just don’t touch anything metal.
The internet says I’m wrong.
Having said that, the best course of action if you can’t wait out the water draining would be to cut the power to the house. The power company can do this. An electrician may be willing to do it. If it was me, I might call the utility company and see what the time line is for them to get out there (though if this is happening, there’s a good chance they’re hours or days out), in which case I’d inform them I’m cutting off the tamper tag and pulling the meter (or say I’m having someone do it) and request they come reconnect it.
While it may not be allowed by their rules, or legal based on your jurisdiction, there is an actual safety issue and the power needs to be cut off.
This is, of course, assuming the breaker box is in the basement or otherwise inaccessible without walking through the water.
Do breakers typically trip if there’s a submersion somewhere?
If more than their rated amperage make it from the hot wire to ground, they would.
Someone sitting right next to me had his basement flood twice in a weekend. They had something like 4 feet of raw sewage fill the basement for hours (x2). I just asked him. His breakers didn’t trip.
Thanks for the info.
Usually a non-gfci breaker will not trip. When an outlet gets flooded, you basically have an electrolysis unit. The current flow depends on ions in the water (salty water will draw more current) and the surface area of metal exposed to the water.
It’s a good idea to replace the traditional breaker with a GFCI breaker.
How can you tell if your breaker is GCFI?
Look at the breaker, there will be a push in switch that says test (similar to the test switches on hair dryer plugs).
Yeah, I don’t have those and they are kind of expensive. If you were just concerned about the basement, and there was only one breaker to the basement, could you just install one?
Yes, GFCI breakers will fit into the same slots that regular breakers fit into (at least for the brands that I’m aware of). There is just a touch of extra wiring inside the breaker box, but beyond that, I don’t believe they’re all that much more difficult to install/replace than regular breakers.
However, you have to be careful. Certain types of motors won’t work with GFCIs. Things like furnace motors, sump pumps etc, may trip it.
However, if you have a sump pump and/or furnace in your basement, they’re very likely on their own breaker anyway.
Boaters die with some (small) regularity from swimming too near a boat at dock and hooked up to shore power with some electricity escaping into the water. Two died in the Great Lakes just a month or so ago, one jumping in to help the first person.
Almost never.
I seem to recall a story where a person died in a swimming pool because an underwater light casing broke. Wouldn’t this be the same as the basement scenario?
Sure.
The thing to understand is: electrical current takes all paths simultaneously. That means that even if the two submerged wires are right next to each other, there is still some (small) amount of current flowing at the far end of the pool. Since it only takes a few mA of current to cause disturbances in heart rhythm, you really don’t want to be anywhere near submerged bare wires.
IIRC, the code does not have sump pumps on GFCI breakers or outlets. You want the pumps to run even if wet. I haven’t looked at that part of the code in a long time though.
Last time I looked at it, it still didn’t. But my understanding is that it’s not about it getting wet, it’s about the motor tripping the GFCI and you don’t want the sump pump to turn off when it needs to be running. Similarly, refrigeration and fire suppression systems aren’t required to be on GFCI for the same reason. They don’t want to risk it tripping due to motors/pumps.
I think pool pumps and air blowers (also motors) are required to be on gfci:
A couple guys died in a Koi pond due to an electrical problem.
Pump blamed for electrocutions at Kings Island - UPI Archives.
Yes, that appears to be the case. Checking the 2017 NEC, pool pumps are required to be GFCI protected. It seems I was mistaken in saying that motors are an exception. What I was likely thinking about it an online discussion I was reading, years ago, where people (mostly electricians) saying that some motors tend to trip GFCIs and they try to avoid having to install them in those locations.
The NEC does not require a refrigerator to have a GFCI outlet, not because of the motor, but because the outlets for fridges tend to be in accessible (ie behind the fridge). They also don’t require them for ice melting equipment, again, because the outlets tend to be up in the eves and not accessible to joe homeowner. Sump pumps usually don’t require them because they’re usually in a ‘non habitable’ part of the house (ie, unfinished basement).
In areas where they would otherwise be required, they can be avoided by using a 240v sump pump and/or hard wiring the pump.
Dedicated fire or burglar alarm circuits are also not required to be GFCI protected, but I’m not sure about the reasoning for that one.
Also, it appears that even if your outlet meets the requirements for not needing to be GFCI protected, if it’s within 6 feet of a sink or bathtub or above a kitchen counter, you still have to have one.
To make everything even more complicated, these are federal codes, your state (generally) adopts them with their own amendments then your city can make further amendments and ultimately your local AHJ gets the final say, especially when it comes to codes that conflict with each other.
I’m thinking the reasoning being they are not vital to health and safety in the same way sump pumps and refrigerators are. I doubt many furnaces are on GFCI for the same reasoning.