When I was a child I always liked to zip my zippers up and down as fast as I could. It did generate a bit of heat due to the friction. I was wondering: Could a stronger (and faster) person zip and unzip a zipper so fast that it could light his/her jacket on fire?
Not before burning their fingers.
This.
wear gloves.
now zippers are plastic and very cool.
Except if your jacket is on fire and the zipper melts and you can’t get it off.
Unfortunately, I knew someone this happened to.