Scram as the original and mostly likely accurate basis for the use of scram in the technical context. A persistent alternative explanation posits that scram is an acronym for 'safety control rod axe man', which was supposedly coined by Enrico Fermi when the world's first nuclear reactor was built under the spectator seating at the University of Chicago's Stagg Field. It could also stand for "Safety Control Rods Activation Mechanism" or "Control Rods Actuator Mechanism". Both of these are probably backronyms from the original, non-technical usage. In any reactor, a SCRAM is achieved by inserting large amounts of negative reactivity mass
Nuclear power in the United States As the industry continued to expand, the Atomic Energy Commission's development and regulatory functions were separated in 1974; the Department of Energy absorbed research and development, while the regulatory branch was spun off and turned into an independent commission known as the U.S. Nuclear Regulatory Commission (USNRC or simply NRC). There has been considerable opposition to the use of nuclear power in the U.S. The first U.S. reactor to face public opposition was Enrico Fermi Nuclear Generating Station in 1957. It was built approximately 30 miles from Detroit and there was opposition from the United Auto Workers Union. Pacific Gas