Continuity mistake: After Clear and Eugene's deaths Kimberley stares out at the lake and the white van outside the hospital, when Tom grabs her and says,'What are you talking about?', she looks over Tom's shoulder and she sees a newspaper report. You see it has two lines for the headline with a blue sheet of paper above it. In the next close up shot of the report it has one line for the headline and the blue paper is lower down. (01:16:25)
Continuity mistake: When Kimberly is being revived, we are seeing blurry images of the doctor and eventually the heart monitor showing she's flat-lining. What we are seeing is what she is seeing, and since she's flat-lining she wouldn't be able to see anything. She also sees when her heart starts beating again, but when they go back to her, her eyes are closed.
Revealing mistake: When Nora's son gets killed, we can see the boy under the falling piece of glass. But in the shot where this piece is just about to smash him, you can see on the DVD edition that there is a dummy instead of him because his arms are too long relatively to the whole body and also the hands are obviously not human. (00:41:20)
Continuity mistake: At the start when the logs fall off of the truck you see only one chain snap off, before this happens you see that the truck has three chains attached to the trailer.
Factual error: When Timmy (the kid who gets crushed by the glass slab) is at the dentist, the tube on the water tank comes off and water spurts out. That tube is the water intake, so if it were to break of it would be sucking in air, it would not be spurting water out.
Revealing mistake: At the beginning of the movie, (outside Kimberly's house when she says, "We're gonna go meet the guys") one of the extras in the background (he is clipping the hedges) keeps looking at the camera. [This was pointed out on the DVD].
Character mistake: If Clear was worried about her safety, why was there a TV monitor in her room that could blow glass or catch fire?
Visible crew/equipment: During the highway pile-up Rory's car barrel rolls in slow motion over an unmanned camera, during this shot you can see the cannon on the bottom of the car used to flip it. Then in the very next shot you see the car barrel roll from a different angle and the unmanned camera from the first shot is visible. It doesn't look like a typical camera, its disguised as debris, but it would not be there had the slow-mo shot not been filmed.
Revealing mistake: In the pile-up scene when Kim's car starts to flip, you can see that the driver side window is removed and placed with plastic wrap, probably to protect the driver. This is on the DVD.