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:
“[As teenager], the trauma of near-misses and almost- consequences usually brings us to our senses. We finally come down someplace between our parents safety advice, which underestimates our ability, and our own unreasonable disregard for safety, which is our childlike wish for invulnerability. Our definition of acceptable risk becomes a product of our own experience.”
—Roger Gould (20th century)
“Love no man in good earnest, nor no further in sport
neither, than with safety of a pure blush thou mayst in
honor come off again.”
—William Shakespeare (15641616)
“Perhaps having built a barricade when youre sixteen provides you with a sort of safety rail. If youve once taken part in building one, even inadvertently, doesnt its usually latent image reappear like a warning signal whenever youre tempted to join the police, or support any manifestation of Law and Order?”
—Jean Genet (19101986)