The name of the character "Dr. Karol Noyman" (played by John Carradine) was recycled by screenwriter Samuel Newman from an entirely different character in his film The Giant Claw (1957) (played there by Edgar Barrier).
Dr. Adam Penner:
Dear Lord, I pray that I am insane, that all that happened is only in my mind. I pray that tomorrow the sun will shine again on living things, not on a world where only the dead walk the Earth.
If the cab of the truck is radiation proof, the hand-held geiger counter Lamont uses would detect nothing.
In the film, John Carradine's character is named Dr. Karol Noymann. In the ending cast list, his character is listed as "Carl Noymann."