scram
Language: English
Part of speech: verb
Pronunciation: enpr: skrăm
ipa: /skɹæm/
rhymes: -æm
Forms: form: scrams
form: scraming
form: scramming
form: scramed
form: scramed
form: scrammed
form: scrammed
form: SCRAM
Etymology: Uncertain; the verb is possibly derived from etymology 1. It has been suggested that the word is an acronym for phrases like “safety control rod actuator mechanism”, “safety cut rope axe man”, “safety control rod axe man”, and “safety control rods activation mechanism”, but these are most likely backronyms.
The noun is probably derived from the verb.
Senses: examples: text: The NCR [Nuclear Regulatory Commission] further demands the plant conform to all the safety requirements put into effect during construction. This means constant re-design. There must also be several ways to scram (emergency shut down) the reactor. Some of these are automatic and some are manual.
ref: 1976 December, Randy Warsaw, “Fermi II – A Plant Tour”, in Ray Barry, editor, The Michigan Technic, volume XCV, number 3, [Ann Arbor, Mich.]: College of Engineering, University of Michigan, →ISSN, →OCLC, page 15:
text: Startup of reactor recirculating pump resulted in flux spike scraming plant.
ref: 1978, “Appendix II—Answers to Written Questions Posed to Nuclear Regulatory Commission before the Hearings”, in Nuclear Regulatory Commission Authorization Requests: Hearings before the Subcommittee on Energy and Power of the Committee on Interstate and Foreign Commerce, House of Representatives, Ninety-fifth Congress, Second Session, on the Nuclear Regulatory Commission’s Requests for an Increased Authorization for Fiscal Year 1978 and for a Fiscal Year 1979 Authorization of $330,000,000: […] (Serial No. 95-161), Washington, D.C.: U.S. Government Printing Office, →OCLC, page 794:
text: The slightest problem in a reactor will cause the control rods to plunge automatically in the uranium core at high speeds (this is called scramming the reactor) and stop the chain reaction.
ref: 1983, Michio Kaku, Jennifer Trainer, editors, Nuclear Power, Both Sides: The Best Arguments for and against the Most Controversial Technology, New York, N.Y.: W[illiam] W[arder] Norton, →ISBN, page 22:
text: Both active and manual methods scram by tripping power to a dedicated pump that unbalances the flows to the^([sic]) passively scram the reactor.
ref: 2000, Ralph R. Fullwood, “Analyzing Nuclear Reactor Safety Systems”, in Probabilistic Safety Assessment in the Chemical and Nuclear Industries, Boston, Mass.: Butterworth-Heinemann, →ISBN, section 6.1.4.3 (ABB PIUS), page 218:
text: The reactor was then "scramed", but the control rods did not slide back into the reactor.
ref: 2007 June 22, Samuel Upton Newtan, “Nuclear Reactor Disasters: Part I: Stationary Reactors (Non-breeders)”, in Nuclear War I and Other Major Nuclear Disasters of the 20th Century, Bloomington, Ind.; Milton Keynes, Buckinghamshire: AuthorHouse, →ISBN, page 113:
text: Raising group eight rods and brining a nuclear reactor fully to life for the first time in nearly ten years—everyone was so ready they were all ready to pee in their pants. Andrews did not know he could do it without SCRAMing the reactor—in other words, pushing it into an automatic shutdown that might be too little too late.
ref: 2012 December 12, D. Michael Battey, chapter 35, in Tenacity Gene, Bloomington, Ind.: iUniverse, →ISBN, page 174:
topics: natural-sciences
physical-sciences
physics
glosses: To shut down (a nuclear reactor or, by extension, some other thing) for safety reasons, usually because of an emergency.
examples: text: This shut off current to the control rod mechanism, and the reactor scrammed (shut off) automatically.
ref: 1984, Charles Perrow, “Nuclear Power as a High-risk System”, in Normal Accidents: Living with High-risk Technologies, Princeton, N.J.: Princeton University Press, published 1999, →ISBN, page 44:
text: As soon as the earthquake struck, the reactors "scrammed"—shut down automatically—as they were supposed to.
ref: 2012, Daniel Yergin, “The Urgency of Fuel Choice”, in The Quest: Energy, Security, and the Remaking of the Modern World, revised edition, New York, N.Y.: Penguin Books, →ISBN, part 3 (The Electric Age), page 415:
text: Immediately after the earthquake, following government regulations, the remaining reactors, 1–3, automatically SCRAMed; control rods shut down sustained fission reactions.
ref: 2016, Nabil Abu el Ata, Rudolf Schmandt, “Understanding the Hidden Risk of Dynamic Complexity”, in The Tyranny of Uncertainty: A New Framework to Predict, Remediate and Monitor Risk, Berlin; Heidelberg: Springer, →DOI, →ISBN, part I (Once upon a Time), page 21:
topics: natural-sciences
physical-sciences
physics
glosses: Of a nuclear reactor or some other thing: to shut down, usually because of an emergency.
Derived terms: word: scramming