Factual error: When any character's automatic pistol runs out of bullets, the slide doesn't lock open. All the weapons shown are of a type which should.
Factual error: The sniper on the roof who is casually picking off zombies hand loads his rifle after every shot. The rifle he is using is the AWP Magnum which has a spring loaded 10 round clip and a breach that cannot be hand-fed ammunition. (00:36:30)
Suggested correction: Ammo can be manually loaded, it's inefficient but not impossible.
Factual error: When the nemesis creature fires a rocket-propelled grenade down the laundry chute/garbage chute at Alice, she protects herself from the blast by a plastic cart. When Alice tips the cart it warps and bends, and even more obviously when Alice leans on the side. There is no way this would have worked, the plastic cart would have been destroyed along with her.
Factual error: In the cemetery scene about 1/4 through the movie, you see a corpse with meal worms eating its head. It's a cemetery, not a bait shop. What, is the corpse a fisherman? I am pretty sure you would never see this in real life. Meal worms eat mostly bran, fruit and vegetables and fish eat them. Worms and maggots yeah, but not mealies.