I wonder if the US 110 voltage came from the way Edison claimed alternating current to be dangerous solely in order to promote his direct current power stations. One Quora answer reads: "110/120 is found there because Edison used DC, and the generators of the time simply couldn’t get much higher than that due to flashover on their commutators…and so their electrical system started out on 110v (actually, due to line losses, many houses only got 90v- and you selected your lightbulbs (90, 100, 110) depending on the line voltage available at your house)"
How come most of the rest of the world uses AC at around 220-250 volts with few problems? Although construction site equipment tends to be 110 volts AC, because of the greater chances of shocks from temporary installatons in wet conditions. I see that these days the US supply voltage to houses is 220 volts AC, split to two 110 volt circuits. In that case, it would be possible to have 220 volt sockets to plug in 220 volt appliances.