The term “flat iron” always brings two images into my mind. The first is a scene from one of the Little House books, where Laura mentions that Ma put flat irons in the bed to warm the sheets on cold nights. Those, of course, were actually regular irons, not the flat irons we all know of, that are for hair.
The other scene is one from Little Women, and it’s the one where Jo is doing Meg’s hair before the ball, and she burns her sisters bangs because the iron tongs are too hot. I can’t imagine doing my hair with iron tongs, but I’ve done enough curling, crimping, and straightening to know that the best thing one can possibly use is something like the ceramic flat irons shown here: http://www.misikko.com/flat-irons.html
Unlike the painted metal hair appliances I grew up with, the Misikko irons won’t stick to your hair – at least, not when used correctly. They don’t mention what may happen if you curl hair that’s already been gelled or sprayed the way we used to in high school (hey, it was the eighties. Space monkey hair was de rigeur). I suspect they wouldn’t be horribly impacted, but I wouldn’t recommend it. Even so, if ceramic hair irons are anything like ceramic cookware, they radiate more intensely at a lower temperature, and work way better than any alternative.
Flat irons are meant for straightening hair, anyway, so spray probably isn’t an issue. As someone who’s always had bone-straight hair, I’ve never had the pleasure of trying to iron mine, only attempts to curl it (which never works well, because my hair is heavy and fine, and the curls fall out), but it’s the rule of life isn’t it, that we who have straight hair always want curls, and the curly girls want their hair straight.
While I’m now an expert on how to care for color treated hair, especially funky colors, and have done every possible thing to my own hair (short of extensions) from cutting my own bangs (not recently, mind you) to having it spiral permed (I think I wanted to iron it when my perms were growing out), to sleeping in cornrows so I could have wild ripply hair the next morning, I can honestly say that I’ve never singed my hair so badly it came off on the curling iron.
I suspect if Jo March had used a ceramic flat iron for Meg, she wouldn’t have had that issue, either.