I was playing the University level. The Glitch happened at the part where you fight the infected and the Bloater. the game's scripted to put on the gas mask when near spores well the game skipped that part and when i fell to fight them, Joel wasn't wearing that gas mask and i fell into a bottomless pit and died . This is the first time this has happened to me, after 7 months of playing the game. I was able to continue after the glitch just thought i would share this.