Originally Posted by
gfunkdave
It's not about protection - it's about the input voltage the thing can take. Small electronics chargers have been made using switching power supplies for the last 10+ years. Switching supplies automatically convert the input voltage to the required output using solid state electronics. Hair dryers don't have a power supply and instead are basically a heating coil and fan motor, both designed to run off the mains voltage in the country of origin. A lot of hair dryers are dual voltage, however, but must be manually switched to the other voltage.
In any case, I'd be very very very careful about wrapping foil around prongs because the foil is liable to get stuck in the outlet and create a shock hazard.
Indeed. But it's sorta one and done. You carefully wrap it on the prongs, stick it in the socket and don't touch it til you leave said hotel or plane.
I don't want a problem to occur but if something gets left behind, well, like I said, the maintenance department will have to come up and fix it. This may entice them to actually do so and install a new and good outlet there.