> The obvious follow up question, then, is: why does Japan use 2-prong outlets even today?
Because JP is behind the times:
> Japan also uses a grounded plug similar to the North American NEMA 5-15.[49] However, it is less common than its NEMA 1-15 equivalent. Since 2005, new Japanese homes are required to have class I grounded sockets for connecting domestic appliances. This rule does not apply for sockets not intended to be used for domestic appliances, but it is strongly advised to have class I sockets throughout the home.[52]
In the same way the old 'best practices' in automobiles didn't mandate ABS or air bags, some country's electrical best practices aren't written to the state of the art.
Everyone is probably looking at IEC 60364 for overall guidelines:
The Europlug is only supposed to be used on double-insulated appliances - those with an insulating outer shell enclosing all live components. Appliances like that do not require a protective earth as a human is not able to contact the live circuitry under normal circumstances. Same reason as light bulbs are not earthed.
Because JP is behind the times:
> Japan also uses a grounded plug similar to the North American NEMA 5-15.[49] However, it is less common than its NEMA 1-15 equivalent. Since 2005, new Japanese homes are required to have class I grounded sockets for connecting domestic appliances. This rule does not apply for sockets not intended to be used for domestic appliances, but it is strongly advised to have class I sockets throughout the home.[52]
* https://en.wikipedia.org/wiki/AC_power_plugs_and_sockets#JIS...
So as things are re-built, you'll see more.
In the same way the old 'best practices' in automobiles didn't mandate ABS or air bags, some country's electrical best practices aren't written to the state of the art.
Everyone is probably looking at IEC 60364 for overall guidelines:
* https://en.wikipedia.org/wiki/IEC_60364
See:
* https://en.wikipedia.org/wiki/Act_on_Product_Safety_of_Elect...