Trivia: Ron Howard's father, Rance, makes a cameo as one of the Cardinals locked in conclave. (00:32:10)
Character mistake: While examining "Diagramma della Verita" in the Vatican archives, Langdon is careful to use a cotton glove and a pair of tongs to turn the pages. But when he returns later to search the Bernini texts for clues about the "fire" church, he turns the book pages with his bare hands. (00:36:30 - 01:04:55)
Character mistake: When Robert and Vittoria arrive at the Vatican archives for the first time, there is a plaque on which it says "Il Processo Galileano", which is misspelled, as the right pronunciation is "GALILEIANO", with the "i" between the "e" and the "a."
Chosen answer: In reality, they would have perished from CO2 poisoning long before the room ran out of breathable oxygen causing them to simply suffocate. Without knowing the exact dimensions of the room it is impossible to give any time more specific than "several hours" for this to happen in a room as big as that one appeared to be.
Phixius ★
I just re-watched the movie, and as Langdon and Vittoria enter the room, it's mentioned to them that the oxygen levels are always kept at a bare minimum to protect the ancient tomes and documents stored there. That helps to answer my own question about why Langdon and the cop were so quickly affected when the power was shut off.
raywest ★