Goofs

In the first scene in the communications room with security director Major Howard, he is shown repeatedly with his second shirt button open and then closed and then open again.

During the Air Force jet scramble, the aircraft shown are F-86 Sabre Jets, while most of the airborne shots are of rocket equipped Lockheed F-94C Starfires.

200 milliroentgens is not anywhere near lethal. For that you would need an exposure of 500 roentgens (about 2500x the dose) for 5 hours. Further, they state earlier that the contamination is alpha particles which generally cannot be lethal unless ingested.

The centrifuge is set up incorrectly, the test subjects would be facing the center of rotation, not the direction of the spin.

Older refurbished Coca-Cola machines can be purchased and product added/money removed by the owner.

When Richard Egan's character first reports to the underground laboratory, his I.D. card is compared to his record they have on file. The two cards are placed on the glass plate of a large slide projector and projected on to a wall. You can see the technician move the cards but the image on the wall doesn't move. Then he removes Egan's card to return it to him but the image remains on the wall.

As the helicopter is coming in on its final landing you can see the pilot is real, but the doctor is a stiff, pale mannequin looking up.

When Dr. Sheppard is shown machines working with dangerous materials, he has to look through several safety scopes with one eye. In the original 3-D version, each shot from his point of view was shown in 3-D.

When they destroy the model city and use the fire extinguisher if you look at the mirror to the left you can see they are on a set.

When the couple are demonstrating weightlessness, you can see the cable supporting the women when the man is holding her above his head.

Dr. Peter Burton, dressed in a radiation suit, tells Dr. Sheppard and Joanna Merritt to stay back as he enters a radioactive hot zone in the chemistry lab, but Sheppard and Merritt follow him in anyway. When Peter carries out a dead scientist - dead from radiation poisoning - Sheppard and Merritt stay behind with a Geiger counter to seek out the radiation source, neither wearing protective gear. Peter soon returns with Dr. Van Ness. Peter discovers and secures a deadly radioactive isotope, but Peter is still the only one wearing a protective suit. The others stand about three to four feet away, watching quietly as Peter's actions expose them to lethal levels of radiation.

The location of the base is supposed to be so secret that even the pilots bringing people to it don't know exactly where it is; the computer guides the helicopter in the last leg of the journey. But there is a Coca-Cola machine on the base. Who refills it and collects the money? There are also Hinkley-Smith water dispensers and a cigarette machine.