depends how strong the concentration is.
When you put it on you may not get a reaction straight away, but you'll see it start to fizz and stuff, you can leave it on for a while, but try rubbing it off after a few seconds (10-20) to start with and see how it goes. Just use a bit of common sense and you'll be ok, you be doing VERY well to ruin the rim either way.
Oh, you may find the rim goes a dark brown/black, that's fine, that will rub off with a cloth or polish.