HELP ME FIND THIS ZOMBIE MOVIE PLEASE

All i can remember is the cover of the dvd tape is like something GAS MASK and has biohazard logo and title has letter on it but im not 100 percent sure because im just a kid back then. The scene i remember is i think they were in a factory the zombie where slow there was a crawling one because hes hips maybe shattered and they were color green as far as i remember. The ending scene where the infected is going inside their building one was eaten in the window because he wants to go out and they start escaping they had 1 girl wearing a hospital gown while escaping hes biting the zombie idk again why. But they manage to escape the last scene is cctv the zombie is walking. This is in 2000s or 2010 sorry for the grammar again.