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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
S. Joseph Cope, Robert B. Hayes
Nuclear Technology | Volume 205 | Number 9 | September 2019 | Pages 1219-1235
Technical Paper | doi.org/10.1080/00295450.2019.1590074
Articles are hosted by Taylor and Francis Online.
The alpha activity discrimination problem between radon progeny and transuranic (TRU) isotopes is evaluated at the times relevant for radiological emergency response using temporal decay properties. This study evaluates various effects from naturally occurring radon progeny creating alpha spectral overlap with the TRU region of interest. The methodology helps to address the potential masking of a radiological threat at worst or, at best, inhibiting response efforts due to delays caused by high levels of radon progeny. This work seeks to provide a rapid, conservative TRU estimation method in as little as 30 min. Surrogate TRU activity is introduced to the assays via check sources as a validation test for discrimination against varied levels of radon progeny collected on environmental air samples. A 2-h activity decay profile counting window was sectioned into multiple combinations of 30-min increments to investigate optimal counting segments and to simulate potential field-collection scenarios with limited resource availability. The experiment sought to discriminate low levels of introduced TRU activity comparable to the natural background on each sampled filter. Using this approach, the study confirmed the utility of the estimation methodology in as little as 30 min. Additional measurement time taken in the decay profile demonstrated marked improvements in both accuracy and precision of the TRU activity estimate as expected. Studies on the potential functional dependence of fitting parameters that influence the TRU estimate and associated uncertainty may improve further model development. The methodology is flexible to accommodate any gross alpha/beta scalar counter and is designed to be implemented within a graded approach based on time and resource availability present in the response. The estimation framework enables rapid air assay with a proper technical basis in times not currently realized in radiological emergency response.