At the opening of the film, the setting is said to be "Zaire, 1967". The country was only called Zaire between 1971 and 1997. In 1967, the country was called the Democratic Republic of the Congo, which was also the name it reverted to after 1997.
When McClintock's helicopter goes under the bridge and splashes into the water while chasing Daniels' helicopter, the pilot can be seen wearing sunglasses. He is not wearing sunglasses in closeup shots.
When Salt looks out the window and notices the troops leaving town they are next to the MPH sign and marching down the street. When he looks out again, after about two minutes, the troops are still marching, but their position has not changed.
The H-6 only has a range of 267 miles. Looking at the direction as Daniels and Salt are flying the helicopter along the coast line, it is clear that they are flying south from Cedar Creek to San Francisco. Now, there are five Cedar Creeks north of San Francisco, the closest one located 180 miles northeast of San Francisco. This Cedar Creek is far from the coast though. The Cedar Creek that is closest to the coast is a whopping 323 miles away, so the flight to SFO and back plus standing in the air against the plane would never have worked without refueling. All of the Cedar Creeks are real creeks anyway, and uninhabited. When preparing for the way back to Cedar Creek Daniel mentions a town called Palisades between San Francisco and Cedar Creek. There is no such town.
When Daniels and Salt talk to George at the San Francisco Federal Building, George says he is from Sioux City, SD. They is no Sioux City, SD. Sioux City is located in Iowa with the suburb of North Sioux City residing in South Dakota.
Blue suits used in level 4 laboratories have a special air supply. The sound this makes inside the suit is so loud that you cannot hear other people. The people at the starting scene of the movie communicates none the less during the first scenes in the level 4 laboratory. Yellow suits are pressurized (positive pressure, which means air can go out if torn, but never in) via a small motor inside it and a set of batteries, but the yellow suits show no sign of being inflated at all, and when helmets are moved no air rushes out.
It means also that Casey tearing his suit shouldn't have ended with infection.
Right before Col. Daniels gets on the C-130 transport, he is talking to Brig. Gen. Ford. As the colonel is about to board the plane, the general salutes him first, which is incorrect military protocol. The lower-ranked officer always salutes first.
The White House Chief of Staff refers to the fuel-air bomb as "the most powerful non-nuclear weapon in our arsenal." This has never been true. In 1995, when this film was made, the most powerful non-nuclear weapon in the U.S. arsenal was the BLU-82 "Daisy Cutter," which is indeed the bomb shown in the film, but which is not a fuel-air bomb. (This weapon was retired in 2001 and replaced by the GBU-43 MOAB bomb, which is currently the most powerful non-nuclear weapon in the U.S. arsenal, and which isn't a fuel-air bomb, either.)
In the beginning of the movie, as the camera passes through the various bio-threat labs, many doors are open to hallways and personnel not wearing masks, and one technician even removes her mask before leaving the lab.
Maj. Gen. Donald McClintock has a Special Forces tab over the Special Forces patch on his right shoulder. This patch represents former overseas combat assignment. The tab is a service school qualification tab to be worn only on the left shoulder according to Army Regulation 670-1.
Maj Salt flies the helicopter from the left seat. U.S. Army helicopters can be flown from either seat but can only be started from the right (pilot/command) seat as the engine starter controls are only accessible from the right side. Also, Maj Salt, being the pilot, would have sat in the right seat even though Col. Daniels outranked him.
When Col. Daniels commandeers the H-6 they put on headsets that are hanging in the helicopter. However, since all military helicopter pilots and aircrew wear helmets with integrated ICS there is no reason why any headsets would ever reasonably be hanging in a military helicopter.
When Sam Daniels checks the blood samples of the patients in Cedar Creek, he uses a compound microscope. However, viruses are too small to be visible to a compound microscope. An electron microscope has to be used.
At the beginning of the movie in both the past and the present the helicopter pilots are clearly not wearing any sort of MOPP gear even though landing in a hot zone. Their exposed faces are clearly scene.
Hospital HVAC Systems are supposed to be designed to not recirculate air from
room to room. The ideal design is so that patients who walk in with broken arms do not walk out with other maladies. However, many hospital HVAC systems are not correctly maintained, and others are not correctly designed - some/many have exam rooms that share air. So when the virus in the movie mutates and is air born, it could be spread by the HVAC System especially in a community hospital that isn't geared up for contagious diseases. In fact, the Llassa fever virus was spread exactly this way in a major US east coast medical center. One person, a tech working on a non-patient floor, contracted the virus even though extreme containment procedures were thought to be in place - the HVAC system was assumed to be the pathway.
When Daniels, Schuler and Salt are first viewing the Motaba virus, the close up shown appears to be a picture of an Ebola Virus. Actually, it is not possible to discern the Ebola virus by its looks from other related viruses. Ebola belongs along with Marburg (and possibly a third, recently discovered virus) to the family of "filoviridae" (meaning "thread-like viruses") that all look the same. It's possible that the (fictional) Motaba virus belongs to the same family and hence looks the same.