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NIST Statement on February 3, 2021, Alert at the NIST Center for Neutron Research

At approximately 9:15 a.m. EST, Feb. 3, 2021, staff at the U.S. Department of Commerce’s National Institute of Standards and Technology (NIST) responded to an alert of elevated radiation levels in the confinement building of the NIST Center for Neutron Research on its Gaithersburg, Maryland, campus.

The alarm occurred during a restart of the research reactor after a regularly scheduled maintenance period. In response to the alarm, staff followed established procedures and immediately initiated a shutdown of the reactor. Several trained radiation workers were exposed to the elevated radiation levels and have been undergoing standard decontamination and evaluation. The health and safety of our staff members is our highest priority, as is protecting their privacy.

There are no indications of radiation above regulatory limits outside of the confinement building, a special area within the NCNR that is built to confine radioactive materials. It includes a filtered ventilation system designed to prevent the external release of radioactive material. All systems appear to have worked as designed and all protocols were followed in a timely manner. NIST will continue to evaluate data from air monitors and other sensors to ensure the health and safety of our campus and local community. NIST is also working to understand the precise cause of the elevated levels of radiation. 

NIST has notified the Nuclear Regulatory Commission and will release additional information when it is available.  

NIST posted an update on the status of the NCNR on February 5, 2021. Read the update.

Released February 3, 2021, Updated May 5, 2021