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The real reason why North America uses 120v instead of 240v.

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nightfire:
To put some stuff as further things in the fire:

The human adult body (depending on the path the current flows) is roughly 1000R-2000R. So with 120V there is half the amount of current flowing through your body, and maybe (as it needs some initial voltage to begin going through your skin) in some cases of thick skin a complete accident would have been avoided.
so 120V/2000 Ohms=60mA ->way more than the 10mA that are regarded as the area where it gets realllly sticky.

When it comes to regulations, it also is important who controls these and who trains the people that do the installation stuff. Here in germany as an electrician, you have to do a longer apprenticeship than most other trades, its 3.5 years. After the exam you still need some masters degree to be able to really run a company alone due to some regulations. Also regarding workspace safety, both by law and by your workplace insurers it is mandated that you have to do some danger assessment of your equipment and regular (read: yearly) testing of your appliances. If you have low stress on them, like PC in an office, you can prolong that to every two years.
So the awareness for safety is a bit higher, and you have ready access to qualfied people.
When you live in an area that is sparsely populated, lots of people are DIY, and thats where potential issues occur. Or people cheap out on quality parts etc.

I also read a statistic from a (i think french) power company where lots of maintenance things were done with trained people under live voltage, and the accidents decreased. Reason: You are aware of the danger and plan accordingly, because one big cause of accidents is routine with experienced people.

Also lots of injuries from electric accidents as the root cause do not originate from the voltage itself, but from surprise and a secondary accident like falling from a ladder. Depending on how this is counted, it also might affect the numbers quite a bit, especially when lots of people in the US due to lack of health insurance avoid going directly to the hospital or doctor.

bdunham7:

--- Quote from: Monkeh on November 24, 2022, 10:15:44 pm ---And I agree that it isn't easy to draw conclusions from the data - but I find it unlikely that the most commonly accessible voltage is in fact safer when fatalities are 20-30x higher for only 6x the population.

--- End quote ---

Hmmm.   Perhaps you haven't met enough of my fellow Americans.  Or seen how some clowns wired my house.

thm_w:

--- Quote from: Monkeh on November 24, 2022, 09:00:01 pm ---
--- Quote from: jpanhalt on November 24, 2022, 08:24:55 pm ---@Monkeh,

If you have so many sources, it should be easy for you to cite at least two comparisons.  So?

--- End quote ---

And your source that 120V actually works out safer in practice? Thought not.

https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/adhocs/14400deathswhereicd10codesw86orw87wererecordedastheunderlyingcauseengland2019to2020registrations
https://www.nfpa.org/-/media/Files/News-and-Research/Fire-statistics-and-reports/Electrical/osFatalElectricalInjuries.pdf

--- End quote ---

UK is actually lower than Canada in terms of electrocution deaths as well (~50%).
Although both are very low overall, 13 for UK per year is nothing compared to other causes (obesity 31k+).

Maybe the shrouded plugs and safety shutters help a bit.

coppice:

--- Quote from: MikeK on November 24, 2022, 06:55:04 pm ---Do countries that use 240V have two out-of-phase 120V lines (like the US actually has), or do they just have a single 240V line?

--- End quote ---
Most countries that supply 220V to 240V power use a single phase. However, I know one country which supplies only 220V power (no 110V or 120V) as two out of phase lines - the Philippines. You have to be a bit careful working on stuff there. Its easy to forget that neither wire is close to ground.

Monkeh:

--- Quote from: bdunham7 on November 24, 2022, 11:54:19 pm ---
--- Quote from: Monkeh on November 24, 2022, 10:15:44 pm ---And I agree that it isn't easy to draw conclusions from the data - but I find it unlikely that the most commonly accessible voltage is in fact safer when fatalities are 20-30x higher for only 6x the population.

--- End quote ---

Hmmm.   Perhaps you haven't met enough of my fellow Americans.  Or seen how some clowns wired my house.

--- End quote ---

I've seen what passes for professionally installed wiring in brand new homes, which is bad enough. Refers straight back to my point on accompanying attitudes.


--- Quote from: thm_w on November 24, 2022, 11:56:51 pm ---UK is actually lower than Canada in terms of electrocution deaths as well (~50%).

--- End quote ---

Is that adjusted for population or absolute? Because the population of England is 50% greater than Canada.

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