Factual error: At the end when the two people are shooting at each other underwater, they both fire about four shots at each other. This isn't possible because a gun needs pressure to reload, or else it would jam after one or two shots. An episode of Mythbusters confirms this.
Factual error: Liquid nitrogen comes in a stainless steel Dewer Flask, which is a larger diameter than shown in the film. The gas cylinders shown, on two occasions, are the type used for high pressure gas, not liquid nitrogen. (00:17:10)