I work for a hospital as well and, like you state, it is conspicuously posted. At my orientation I was told that working at a hospital was as dangerous as working the night shift at a gas station. I wanted to raise my hand and ask, "Why then do you deprive legally armed individuals of their right to self-defense?" but thought better of it. Luckily I will be graduated in a year and will have the luxury of choosing who I will and will not work for.