NNSA just checked Oklahoma off the list of states cleared of cesium irradiators. This is a major milestone in enhancing security across the nation. Read more about how NNSA worked to eliminate the radiological risk these devices pose.
National Nuclear Security Administration
December 3, 2025
minute read time
WASHINGTON – In a significant advancement for national security, the U.S. Department of Energy’s National Nuclear Security Administration (NNSA) has removed all cesium-137 irradiators from the state of Oklahoma. This achievement marks a critical step in NNSA’s mission to eliminate radiological risks across the United States and keep American communities safe.
Used for medical applications such as blood treatment and cancer research, irradiators are a critical part of America’s infrastructure. However, many of these irradiators contain cesium-137, a radioactive material that poses a serious risk if it is stolen and used to produce a radiological dispersal device, also known as a “dirty bomb.”
“Clearing states of these irradiators showcases NNSA’s commitment to making U.S. communities safer and more secure,” said Matthew Napoli, NNSA Deputy Administrator for Defense Nuclear Nonproliferation. “With Oklahoma now added to the growing list of states cleared of cesium irradiators, NNSA proudly recognizes this milestone in enhancing national security.”
Oklahoma is the 12th U.S. state or territory to be free of cesium irradiators, joining Alaska, Arizona, Delaware, Idaho, Iowa, Kansas, Nevada, New Mexico, Puerto Rico, South Dakota, and Wyoming.
“Clearing states of these irradiators showcases NNSA’s commitment to making U.S. communities safer and more secure. With Oklahoma now added to the growing list of states cleared of cesium irradiators, NNSA proudly recognizes this milestone in enhancing national security.”
– Matthew Napoli
NNSA Deputy Administrator for Defense Nuclear Nonproliferation.
The Oklahoma cleanout was made possible through a partnership with the Oklahoma Medical Research Foundation, which participated in NNSA’s Cesium Irradiator Replacement Project. This voluntary program incentivizes users of cesium irradiators to transition to safer alternatives.
“We are proud to advance our research mission while supporting efforts that strengthen the security of our communities,” said Trent Brown at Oklahoma Medical Research Foundation. “Thanks to NNSA’s Cesium Irradiator Replacement Project, we are able to replace our technology with safer alternatives, making our community safer.”
NNSA’s Office of Radiological Security enhances U.S. and global security through a two-pronged approach of eliminating risk by removing high-activity radioactive material and preventing adversaries from acquiring this material through strong industry, law enforcement, and government partnerships. These efforts safeguard American interests and promote a safer and more secure America.