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by sbazerque 1531 days ago
This may be one of those famous last words, but friend, I do my own electrical work.
2 comments

Well, the engineering panels around here believe I'm qualified to do my own electrical work, but I wouldn't get on the bureaucracy of convincing my local power company.

Anyway, home wiring is not hard, and many people do it for a living with a ridiculously low amount of qualification (and competence). If you are not touching the public wires, the safety rules are very simple and the odds are good that you can give them more care than somebody that has been doing the work every day for a decade.

(But well, if you don't know how to do it safely, or if you won't be bothered to follow them, you shouldn't be doing it.)

My dad did as well... my job for many years as a child was to stand there with a broom in case it went bad. Be careful!!!
There's a difference between "doing your own electrical work" and "working on live electrical wires"!

Although sometimes the latter happens.

Rubber-soled shoes, one hand in back pocket at all times, non-conducting tools, and a helper with a wooden broom handle who knows mouth-to-mouth resuscitation ... these are all good recommendations. :)

Is "one hand in back pocket at all times" to avoid a circuit across your heart? And what is the wooden broom handle for?
Yes -- one hand does the work and is more likely to come into contact with energized wires or rails. If the other hand is supporting your lean against the conduit or enclosure (grounded), the path is through your heart. We're conditioned to use both hands for everything, so it's extremely easy to "forget" or "cheat just for this step" and use the other hand to balance, or hold, etc. Having your hand firmly in your back pocket is unfamiliar enough that we remember, and far enough that a quick instinctive response is interrupted.

Wooden broom handle is a non-conducting lever that a helper can use to separate you from the energized equipment. The current can cause your hand muscles to spasm in a "gripped" position, so the broom handle might need to be applied with some force. This is a last-resort catastrophic situation response.

The way that electricity flows through a conductive medium, it doesn't matter if the circuit appears to "crosses your heart", because some portion of it will still flow through your heart regardless.

Or, to put another way, you'll still see current at the heart even if it only flows through two fingers on the same hand. And even if it's a really small portion of the current, it doesn't take much to stop a heart.

Plus, there are a virtually unlimited number of proven tools for seeing if the circuit is live (even if there's no current flowing) to rely on such dodgy methods.

Agreed that electrical potential is present in all points of a uniform conductor. And that it takes only a tiny amount of current to interrupt a beating heart (as low as 60mA).

However it is not correct that the path of the current is not important.

Current will not flow between two points of equal electrical potential. There are some complications in the modelling (skin is a better insulator than internal bits, bags of salty moist flesh and bones are not resistively consistent, etc), but you're still in a much better situation to reduce potential difference across your heart, if the external potential difference occurs between two fingers on the same hand, vs two fingers on opposite hands.

OSHA says:

> The currents that pass through the heart or nervous system are the most dangerous. ... If a hand comes in contact with an electrical component with current (and at the same time the other side of your body makes a path to the ground), this will make the current pass through your chest and possibly produce injuries to the heart and lungs.

https://www.osha.gov/sites/default/files/2019-04/Basic_Elect...

> However it is not correct that the path of the current is not important.

I never claimed this. I claimed that even with the "safest" path through your body, the chance of your heart stopping is still there.

My point is that it's never "safe" to do, and as a homeowner (and even for a vast majority of non-lineman electricians) you never have to do it.

> Plus, there are a virtually unlimited number of proven tools for seeing if the circuit is live (even if there's no current flowing) to rely on such dodgy methods.

Yes. Use those. But this discussion is about when you are working on live wires, and you know you are working on live wires.

A homeowner will never have to do this. And an electrician has the ability to ensure they too don't have to ever work on live wires (despite many's insistence in doing so, something about machismo, etc.).
The pros seem to give less of a shit about live wires than I do, from what I've seen. And I already give fewer shits than I probably should.
You’re literally risking her life on those things, to save some money ?
I have no idea what you are talking about. I'm risking no one's anything.

At worst, I'm acknowledging reality. Some people sometimes end up working on live wires. If you can't be talked out of this decision (or if it's legitimately not possible to avoid), a dose of caution is important.

Asking an untrained non-adult to be ready with a broom is a fantastically bad idea though. In the worst case, the kid lives with the memory of uselessly smacking their parent's corpse with a broom while the air fills with the smell of ozone and burnt flesh.