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Update on the Status of the NIST Center for Neutron Research (NCNR)

The research reactor on NIST’s Gaithersburg, Maryland, campus is shut down and in a safe state. It will remain in shutdown status until the cause of the elevated radiation levels is determined and corrected. The elevated levels of radiation within the NCNR’s confinement building have dropped significantly, as expected. Radiation levels outside the confinement building have always been significantly below regulatory health and safety limits and have returned to their normal level of hundreds of times below those limits. 

The staff members who received elevated exposures underwent prompt decontamination and screening, and all were cleared to go home by the evening of Wednesday, Feb. 3, 2021. On Thursday, Feb. 4, 2021, the affected staff members received additional screening that will help determine the precise doses they received. We have confirmed that no employee received doses in excess of limits established for radiation workers. The NCNR continues to be fully staffed 24 hours a day.

With safety as our No. 1 priority, NIST is now in a phase of careful and deliberate planning. The first step will be to develop a plan for safely assessing the condition of the reactor so that the root cause of the elevated radiation levels can be investigated. Once that root cause is determined, NIST will identify and then implement all necessary corrective actions.

We have heard concerns from our local community and want to reassure our neighbors that the Nuclear Regulatory Commission (NRC) has stated it is “satisfied the facility is safely shut down and the public around and near the facility remains safe.”

The NRC has strict requirements for the safe and secure operation of research reactors such as the one at NIST. It is important to note that the NIST research reactor differs from a nuclear power reactor in almost every way, including size, power, temperature, pressure, design and purpose. At full power, the NIST research reactor produces 20 megawatts of thermal power. In contrast, a power reactor produces 2,000 to 3,000 megawatts of thermal power. The NIST research reactor is much smaller and simpler and operates at atmospheric pressure and a temperature of about 130 F (54 C) — cooler than many residential water heaters.

These characteristics result in an extremely low-risk facility that brings enormous research benefits to the nation. Redundant cooling and shutdown systems (either automated or operator-activated) and backup electrical power ensure that the reactor can always be shut down safely and quickly. Testing ensures these systems operate properly; each system is different, but some are tested monthly and most are tested prior to operating the reactor.

NIST has operated the NCNR safely for more than 50 years, providing a premier research facility serving more than 2,500 researchers from across the U.S. each year. Their research has improved our understanding of a wide variety of materials and phenomena, helping to improve pharmaceuticals, high-tech alloys, data storage and much more.

NIST leadership and staff are committed to determining what caused the Feb. 3, 2021, elevated radiation levels and to ensuring the safety of our staff, visitors and community.

Released February 5, 2021, Updated May 5, 2021