There are two radiation beings at the start, one of them collapses in the hall and its radiation suit is found empty. Then miraculously during the second attack, there are two radiation beings in suits. It gets worse. Eventually there are four radiation beings, and another one collapses in the hall when it is isolated from the radiation by the shielding, but shortly thereafter there are five radiation beings in suits. Then the number of beings magically increases to seven. It might be argued that the beings are multiplying, but the number of radiation suits would not.
Dr. Marshall goes into a long speech about exotic particles and at one point says there is matter that doesn't obey the law of gravity. ALL matter regardless of how exotic exerts and is affected by gravity.
Dr. Marshall lists something he calls the lambda series, there is no such thing in Nuclear Physics.
Dr. Marshall lists one of the radioactive isotopes as Berklium-245, the correct name is Berkelium-245.
Dr. Marshall lists an isotope Famium-252, there is no known element with the name Famium.
When reaction technicians move radiation shields on casters, they maneuver them so easily that it's obvious the shields aren't made of real lead.
After Dr. Marshall finishes assembling the fusion bomb, he leaves it in the fissionable materials vault and locks the door. He is still inside at the time, and there is no other way for him to leave the vault.
The console below in the control room (below the window viewing the reactor room) is an audio control console. The meters seen on it are VU meters. This console would have nothing to do with radioactivity or experiments dealing with it.
At about the 19 minute mark, when Griffin bounds into the room to tell Dr. Marshall of the impending doom, the set floor flexes so much that the "equipment" stacked behind and to the side of Dr. Marshall sways back and forth very noticeably.
When Arndis Pollard rushes into the reactor room to rescue her husband moving flashes of light can be seen playing over the walls and furniture. Then when Griffin follows her into the room, the camera pulls back to briefly reveal a rotating "disco ball" at the edge of the frame, the reflections off which are the source of flickering lights.