X-ray ankle procedure?

I broke my ankle a few months ago and every time I have gotten X-rays they put a lead bib on my midsection for whatever reason. Just a few days ago I got x-rayed again by this radiologist who didn't put it on before my X-ray. Question is why do they put that on you, and should I be concerned she didn't put it on before she did the X-rays. She was totally rude and not concerned with me at all as her an a fellow nurse were engulfed in some pointless chatter...