Safety
In most reactor designs, as a safety measure, control rods are attached to the lifting machinery by electromagnets, rather than direct mechanical linkage. This means that automatically in the event of power failure, or if manually invoked due to failure of the lifting machinery, the control rods will fall, under gravity, fully into the pile to stop the reaction. A notable exception to this fail-safe mode of operation is the BWR which requires the hydraulical insertion of control rods in the event of an emergency shut-down, using water from a special tank that is under high nitrogen pressure. Quickly shutting down a reactor in this way is called scramming the reactor.
Read more about this topic: Control Rod
Famous quotes containing the word safety:
“There was only one catch and that was Catch-22, which specified that a concern for one’s own safety in the face of dangers that were real and immediate was the process of a rational mind.... Orr would be crazy to fly more missions and sane if he didn’t, but if he was sane he had to fly them. If he flew them he was crazy and didn’t have to; but if he didn’t want to he was sane and had to.”
—Joseph Heller (b. 1923)
“If we can find a principle to guide us in the handling of the child between nine and eighteen months, we can see that we need to allow enough opportunity for handling and investigation of objects to further intellectual development and just enough restriction required for family harmony and for the safety of the child.”
—Selma H. Fraiberg (20th century)
“For hours, in fall days, I watched the ducks cunningly tack and veer and hold the middle of the pond, far from the sportsman;... but what beside safety they got by sailing in the middle of Walden I do not know, unless they love its water for the same reason that I do.”
—Henry David Thoreau (1817–1862)