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:
“The Declaration [of Independence] was not a protest against government, but against the excess of government. It prescribed the proper role of government, to secure the rights of individuals and to effect their safety and happiness. In modern society, no individual can do this alone. So government is not a necessary evil but a necessary good.”
—Gerald R. Ford (b. 1913)
“I nightly offer up my prayers to the throne of grace for the health and safety of you all, and that we ought all to rely with confidence on the promises of our dear redeemer, and give him our hearts. This is all he requires and all that we can do, and if we sincerely do this, we are sure of salvation through his atonement.”
—Andrew Jackson (1767–1845)
“A lover is never a completely self-reliant person viewing the world through his own eyes, but a hostage to a certain delusion. He becomes a perjurer, all his thoughts and emotions being directed with reference, not to an accurate and just appraisal of the real world but rather to the safety and exaltation of his loved one, and the madness with which he pursues her, transmogrifying his attention, blinds him like a victim.”
—Alexander Theroux (b. 1940)