Originally Posted by
lwildernorva
Through several sources, I've heard that hair dryers aren't so reliably protected, but I don't use one of those normally unless the hotel/B&B provides it and then, it's only to dry clothes, not my hair.
Originally Posted by
paperwastage
Your hairdryer typically runs above 1000 Watts, so it's not good to plug into the travel converter and overload it
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.