The door creaks and clangs with the thud of the gunshots. The two men try to lock the door, but the zombies are so strong that they can't be let out. The door has no switches or buttons, so they have to open it themselves. They find a card in the passage that they think is an id card from the engineering department. They try to open the door and find that the door is open. They hurry up to the door. They wait for the door to open, and then they open it. They see that there are some zombies in the room. They decide to let the two men go at once, but then they wonder if they can hold them off by themselves. If they run together, they'd be done for if they were knocked down. They'll be safe even if they attract more zombies. The gunshots sound like they're going to kill the two of them, and they hurry up and run. They just need a few seconds to hold off the zombies.