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From: john larkin <JL@gct.com>
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Subject: Re: electrical deaths
Date: Mon, 02 Dec 2024 19:24:04 -0800
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On Mon, 2 Dec 2024 23:54:27 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>Joe Gwinn <joegwinn@comcast.net> wrote:
>> On Mon, 2 Dec 2024 13:40:13 -0800, Joerg <news@analogconsultants.com>
>> wrote:
>> 
>>> On 12/2/24 1:17 PM, Joe Gwinn wrote:
>>>> On Mon, 2 Dec 2024 11:35:41 -0800, Joerg <news@analogconsultants.com>
>>>> wrote:
>>>> 
>>>>> On 12/1/24 9:59 AM, Joe Gwinn wrote:
>>>>>> On Sat, 30 Nov 2024 14:24:11 -0800, Joerg <news@analogconsultants.com>
>>>>>> wrote:
>>>>>> 
>>>>>>> On 11/26/24 6:53 PM, john larkin wrote:
>>>>>>>> https://www.researchgate.net/figure/Age-adjusted-mortality-rates-from-electrical-injuries-per-1-million-population-European_fig1_221916189
>>>>>>>> 
>>>>>>>> The US (0.63 PPM) is probably low partly because we have mostly 120
>>>>>>>> volt gadgets. I usually wire boxes hot, and get tickled now and then,
>>>>>>>> no big deal.
>>>>>>>> 
>>>>>>>> Some countries are astounding.
>>>>>>>> 
>>>>>>> 
>>>>>>> Twice the line voltage makes a difference. Also, some countries such as
>>>>>>> Germany have non-polarized wall outlets which was a clear mistake on the
>>>>>>> part of the standards guys. Think toasters and forks.
>>>>>> 
>>>>>> We have polarized line plugs in the US, but the wiring old and new
>>>>>> isn't consistent, or becomes so over time.  And so people often
>>>>>> intentionally defeat the polarization.
>>>>>> 
>>>>>> Part of the problem is that for many small appliances, the plug was
>>>>>> bigger than the appliance.  Probably more expensive too.
>>>>>> 
>>>>>> Anyway, my instinct is that not polarizing plugs and sockets is more
>>>>>> realistic, as it forces manufacturers to pass safety regardless of hoe
>>>>>> things are plugged in.
>>>>>> 
>>>>> 
>>>>> Polarization can save the day with toasters and similar appliances. Then
>>>>> you can make sure that neutral comes in at the top end of the meanders.
>>>>> In the US, 99+ percent of cases will not have line and neutral reversed.
>>>> 
>>>> I think that the 99+ percent is quite optimistic, especially on older
>>>> buildings.  Back when I was an apartment-dweller, ran into all manner
>>>> of trouble, to the point that one of the first things I did in a new
>>>> apartment, was to turn the power off and opened all electric boxes,
>>>> and straighten out the "carpenter wiring", much of this being
>>>> dangerous.
>>>> 
>>> 
>>> Not too optimistic, I think. The home inspector we used was a seasoned 
>>> guy and he said outlets where line and neutral are reversed were very 
>>> rare. He made it a habit of testing them all.
>>> 
>>> 
>>>> War Story One:  In the 1970s in Washington, DC, my boss was having
>>>> considerable problems with the lights in his newish house in the
>>>> suburbs.  For instance, when he turned one light on, an unrelated
>>>> light would go off.  I said it sounded like some kind of grounding
>>>> problem.  Eventually he invited me to dinner in his house, and bring
>>>> your voltmeter.  Which I did.  It turned out that the solid copper
>>>> wires at every electrical device (wall switch, outlet, light, et al)
>>>> were loose - the electrician (or his assistant had forgotten to
>>>> tighten all the terminal screws down.  (Stranded wire was not used
>>>> then.)  So boss called the builder to have all those neglected
>>>> terminal screws tightened properly.  He was lucky that there wasn't a
>>>> fire.
>>>> 
>>> 
>>> That's a serious blunder by a contractor. 
>> 
>> It certainly was, but if the house had burned down, good luck figuring
>> out why from inspection of the ashes.
>> 
>> There is an electrical inspector whose approval is required before the
>> house can be occupied, but they do not generally test that the screws
>> are tight.
>> 
>> What probably happened is that the electrician had an apprentice, and
>> so the electrician does the hooking up and the apprentice checks that
>> it's correct (and thus learns) and does the final tightening.  They
>> somehow got distracted, and the last step never happened.
>> 
>> 
>>> In Germany we had mandatory 
>>> road-worthiness checks for cars every two years. I think they still do. 
>>> The inspector came up from underneath my dad's car with a pale face. 
>>> "Sir, come down here, you've got to see this". The four connector bolts 
>>> of a universal joint in the steering column were in there alright but 
>>> the mechanic had forgotten to put any of the nuts on them, let alone 
>>> tighten anything. They were just rattling around in their holes without 
>>> nuts. My dad was one of the guys who floored it on autobahns, 120mph and 
>>> more. That could have resulted in a horrific accident.
>> 
>> Good lord.  That would have killed many people.
>> 
>> 
>>>> War Story Two.  Ten years later, in Baltimore, MD, some friends
>>>> complained that their kitchen light (in the center of the ceiling)
>>>> flickered, and mentioned that when they used the sink in the washroom
>>>> off the kitchen, sparks fell from underneath that sink.  I didn't
>>>> believe them at first, but they persisted.  It turned out that the
>>>> building (which was quite old) still had some old knob-and-tube
>>>> wiring.  The plumbers had recently replaced the drain pipe from the
>>>> bathroom above the washroom with a new copper pipe, and had barged
>>>> through the existing knob-and-tube wiring, breaking the return path,
>>>> but accidentally making the drain pipe live.  The current made it from
>>>> the copper drain pipe to the existing cast iron drain through the
>>>> hardware on the washroom sink.  Stopgap was to firmly ground the drain
>>>> pipe.  I assume the owner of the building had words with the plumber,
>>>> and got an electrician.  Anyway, nobody was hurt, and nothing burnt
>>>> down.
>>>> 
>>>> I have many such stories, but this will do for now.
>>>> 
>>>> And I bet that Europe also has its heart-stopping stories.
>>>> 
>>> 
>>> Over there it's often willful neglect. I sat at a pcinic table of a 
>>> campground in Italy, having some wine with the owner. The lights 
>>> flickered and a loud phzzzzt was heard, sparks flew. The overhead cable 
>>> to the freezer at the (very far away) end of that line was arcing. "I 
>>> think we should turn this off and run an extension cord" ... "Nah, 
>>> happens a lot, it'll hang on for a while. I'll fix this tomorrow. Or the 
>>> day after".
>> 
>> Yes, very often exactly that.  I have similar stories.
>> 
>> 
>>>> 
>>>> PS:  I do prefer the Euro-style closed terminals that work for
>>>> stranded and solid wire.  They are allowed in the US, but not all that
>>>> common outside of industrial sites.  One big advantage is that they
>>>> take far less volume than wire-nuts and the like.
>>>> 
>>> 
>>> Yes but unfortunately most of them contain just a screw and not a 
>>> pressure plate. You are supposed to use ferrules on stranded wire but 
>>> hardly anyone does.
>> 
>> I don't either, because the approved euro terminal strips don't
>> provide plates for the smaller wire sizes.  I also use the euro
>> terminal strips inside appliances, and if I'm connecting finely
>> stranded wire, I tin the wire with 63-37 solder to consolidate it, and
>> clamp that.
>> 
>> Joe Gwinn
>> 
>
>Electrical codes contain a lot of non-obvious and very expensive wisdom. 
>
>Cheers 
>
>Phil Hobbs 

I've asked a few electricians if they have read the building codes.
None have.