beginner's foils are not metal, they are plastic. they don't have the mechanical tip and are not dangerous. as far as thrusting at someone with a think object made of plastic.
*if* the tip breaks, *if* you hit someone with a broken tip, *if* you get them in the throat, only then you could get injured.
still, it's stupid to not get the jacket, because fencing without it would hurt you.
fyi i fenced @ Academia Musumeci Greco
http://www.accademiagreco.it/
so i kinda know what i'm talking bout.
its still kinda weird that someone *not* in a fencing school would want to fence, because no school would ever let you on the floor without full uniform.
It's not a matter of safety, its a matter of tradition.
although i gotta say - i like mikeford's answer. he is in a FencingClub, and the first rule of FencingClub is: you don't talk about FencingClub.
in which case i suggest something better than a foil:
http://sbg-sword-store.sword-buyers-guide.com/product275.html