In the crew quarters, the suit computer says that there is a vacuum. A vacuum should not be possible within the ship even with a malfunctioning life support system unless the section is at the outer hull.
When the Player enters an airlock from the vacuum side, air is blown outwards towards him. An airlock is supposed to equalize pressure on its own by containing the air within in a container such as an oxygen bottle; this is to prevent air from being wasted by being blown into space.
Whenever the player immolates a Necromorph with the flamethrower, the creature will be set ablaze, but will suddenly become dismembered rather then get charred and dehydrated.
Oxygen stations are conveniently only available in places where a vacuum exists. Considering that the U.S.G.C. Ishimura is a spaceship, they should be all over the ship.
Signs outside the elevators may say 'Call The Tram'. Elevators are not trams.
When the Player is tasked with removing radioactive orbs from the ship, he must open a door leading outside. Doing so blows all the air out, but the radioactive orbs don't move.
When the Player receives a live transmission, the suit says 'Playback Audiolog'. An audiolog is a recording, not a live transmission.
The computer announces that refueling is complete even before it has finished starting.