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Yes, it's entirely a function of voltage. But the safe limit for DC voltage is lower for two reasons:

- A shock from a DC supply will cause heart fibrillations at lower voltage than AC, because of the way muscles receive signals from nerves

- An electrical arc from a DC line will burn continuously, while an AC arc tends to self-extinguish at each zero-crossing.

So in practice, 120 VAC or 48 VDC are the limits for household wiring.




> So in practice, 120 VAC or 48 VDC are the limits for household wiring

About 20% of the world uses 110-120 V and 60Hz. The rest uses mostly 240V at 50Hz.

Although 110V is safer, the US seems to ignore many of the safety features I see used elsewhere in the world.

How that translates to deaths per million people per year comparing to similarly rich countries, I don't know.


>A shock from a DC supply will cause heart fibrillations at lower voltage than AC, because of the way muscles receive signals from nerves

That is opposite to my understanding. The extra shock hazard of AC vs DC was an argument used against AC power distribution back in the day. The 50V limit is to prevent shock altogether.




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