Continuity mistake: When the female nurse is in her 4x4 vehicle, she looks in her mirror and sees two fire trucks. In the far away shot the first fire engine overtakes her, then when it cuts back to her it's overtaking her again. (00:34:30)
Suggested correction: This appears to be a not uncommon film making technique where a sequence is shown from multiple angles, and if that is the case here, then it isn't a mistake.
But as we have no way to tell if it is an intentional technique it's considered a mistake.
Continuity mistake: Near the start, Roark is down in the drain and part of his mask melts. When he is back at the surface the mask is in perfect condition. (00:15:00)
Suggested correction: It was not a mask but some equipment on his chest near the radio, which looks pretty burned, when he finally gets outside.
Factual error: The volcanic ash that can be seen throughout the film is too big to be real. The ash shown is something like 1-2 cm in diameter. Volcanic ash is not that big in real life; it is not more than 2 millimetres in diameter. (01:02:30)
Suggested correction: There are different types of products from volcanic eruptions: Ash, lapilli, and bombs. Ash is what everybody knows as. Lapilli is about the size of pebbles. Bombs, as shown in the movie, are large rocks on fire that can explode as they did in the movie.
The picture shows items that are smaller than a pebble, but too large to be ash.
Suggested correction: This in the middle of a city, where various things were catching fire, so that ash might not be exclusively from the volcano, but from burning buildings and objects nearby.
Character mistake: When they're literally watching lava creep down the street Roark says "whatever this stuff is" (something like that). 2 things: 1) how does he not realise it's lava, and 2) although it's weird to have lava in LA, Amy already told him that lava could push through from the tar pits, so he should have been able to figure it out.
Suggested correction: Even if he knows what it is, he is still in denial and just doesn't want to say the name of it, as it's uncomfortable to say.
