Generator Malfunction Sickens Over 60 Navy Service Members on USS Nebraska Submarine

More than 60 U.S. Navy service members became sick after a generator malfunction aboard the ballistic missile submarine USS Nebraska, according to a report.

Crews were operating the submarine’s backup diesel generator during a routine pier shift at Naval Base Kitsap-Bangor in Washington state on June 22 when they were exposed to diesel exhaust fumes, said Lieutenant Zachary Anderson, a spokesman for Submarine Group 9, according to the military newspaper Stars and Stripes.

In total, 64 service members were sent to medical centers to treat their symptoms, which included coughing, headaches, dizziness and nausea. They also reported experiencing irritation of the eyes, nose and throat.

Six sailors were hospitalized for further medical attention, but all have since been released.

It was not immediately clear what caused the issue. Officials said they will take corrective action as appropriate, according to the report.

After the incident, crew members cleared the inside of the submarine, provided medical assistance and then returned to normal operations, Anderson said.

The Independent has contacted the Navy for more information.

The diesel generator does not affect the submarine’s nuclear reactor when running, and the reactor was undisturbed during the incident, the Navy noted in its statement.

Nebraska is one of eight Ohio-class ballistic missile submarines at the base in Washington state. The Ohio class is named after Ohio because the USS Ohio submarine is the lead submarine in its group, according to The Columbus Dispatch.

The 560-foot-long submarine is designed to carry ballistic missiles and nuclear warheads. The submarine can also descend to depths as low as 800 feet below the surface, according to Navy Times.

The submarine was used in the U.S. military strikes against Iran’s nuclear facilities as part of Operation Midnight Hammer in June 2025, according to Navy Times.