During the conversation between the health physicist and fire chief, and while the men are all waiting for the firefighters to emerge from the reactor, the health physicist's coveralls switch from being zipped up all the way, to unzipped 3 inches.
After the health physicists load the nurse and driver into the car, one health physicist initiates shutting the door, yet the other health physicist finishes shutting it.
Two of the firefighters have beards. The actual firefighters who responded to the SL-1 alarm in 1961 were not allowed to have beards because the hair would prevent their breathing masks from sealing properly.