A reactor operator (or nuclear reactor operator) is an individual at a nuclear power plant or other nuclear reactor who is responsible for directly controlling the reactor core. This is typically done using control rods, aided by information from other instruments, such as neutron detectors, thermometers, and radiation detectors.
In addition to controlling the reactor core, the responsibilities of reactor operators may include control of other important reactor equipment, logging and recording of reactor activities, monitoring of reactor parameters, response to adverse or unexpected reactor conditions, maintenance and care of equipment, and emergency preparedness and response. As they are responsible for manipulation of the control rods, reactor operators are the only individuals at a reactor who can significantly alter amounts of core reactivity.
All reactor operators are required to be licensed or qualified by their respective governing body (for example, the Nuclear Regulatory Commission for U.S. civilian nuclear reactors and Naval Reactors for U.S. naval reactors). Because of the risk of catastrophic consequences from incidents in reactor cores, reactor operators are often subject to stringent mental and physical health requirements.
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The history of reactor operators began with the first artificial nuclear reactor, Chicago Pile-1. Although the experimenters there lacked any formal system of certifications in nuclear operations, physicist George Weil arguably became the first reactor operator, as he was responsible for the physical movement of the control rods.[1] Reactors, for both research and plutonium production, proliferated, both across the United States and the other burgeoning nuclear powers. The Obninsk Nuclear Power Plant, the first nuclear power plant, was opened in 1951.[2]
These reactors continued to be operated by scientists, technicians, and engineers trained on the job, without any centralized national oversight. In the 1950s, many of these programs were brought under the regulation of national bodies, such as the Atomic Energy Commission (AEC)[3], United Kingdom Atomic Energy Authority (UKAEA),[4] Japanese Atomic Energy Commission,[5] and the Ministry of Medium Machine-Building.[6] This increasing centralization was not without some opposition, as in the United States, where AEC chairman Lewis Strauss argued against the AEC having the power to regulate reactor operator selection. Nevertheless, in 1955 it required operators to pass a test and a medical examination in order to be licensed to operate.[3]
Following the Three Mile Island accident and heated debate on new operator regulations, in 1984 the Nuclear Regulatory Commission (successor to the AEC), approved the nuclear industry's proposals to require prospective operators to have combinations of college education, service in the nuclear Navy, training on simulators, and operating experience. The next year, it published Training and Qualification of Nuclear Power Plant Personnel, which endorsed the Institute of Nuclear Power Operations's program for operator training.[3]
In 1987, the NRC shut down the Peach Bottom reactors after discovering operators had been sleeping, playing video games, and reading magazines while on duty.[3] INPO claimed this was indicative not of failures in regulation but of a lack of professionalism among operators.[7]
In the United States, the 2024 median annual salary for a licensed reactor operator was $122,610.[8] The Bureau of Labor Statistics predicts a 15% decline in reactor operator jobs from 2024 to 2034.[9]
There are two types of civilian reactor operators licensed by the NRC: reactor operators (RO) and senior reactor operators (SRO).[10][11] A reactor operator is licensed to manipulate the controls of a reactor (which may alter reactivity and therefore change the power level) while a senior reactor operator may both manipulate controls and direct the activities of reactor operators.[10] Typically, this means that an RO or SRO is qualified to remotely operate control rods and other remote actions required to control the reactor as desired.
In addition, a senior reactor operator is the senior watch stander in a control room and is responsible for directing the operation of the nuclear reactor as desired.[12] They also may be authorized to direct fuel movement/core alterations within the reactor vessel.[13]
A senior reactor operator (like pilots in command[14] and masters of ships at sea[15]) is authorized by law to depart from regulations during emergencies. 10CFR50.54 (x) and (y) state that reactors may violate the conditions of their license or technical specifications in an emergency when no other option is apparent to protect public health & safety. However, they also require that such actions be approved by a senior reactor operator.[12]
A reactor operator is an individual who has met the licensing requirements of 10CFR55 and NUREG-1021 for being a reactor operator. For reactor operators at power reactors, these requirements include:
A senior reactor operator is an individual who has met the licensing requirements of 10CFR55 and NUREG-1021 for being a senior reactor operator. These requirements are similar to the requirements for a reactor operator, except:
Again, these requirements apply only to staff at power reactors.
The only other person who may manipulate the controls of a US civilian nuclear reactor is an individual who: