The Sandia National Laboratories have temporarily dropped a requirement that all employees be vaccinated against COVID-19, leaving only a pair of National Nuclear Security Administration (NNSA)-owned sites that require vaccination.

While Sandia’s mandate is paused, “the discipline process for those employees who are unvaccinated, and processing of religious and medical accommodations are on hold,” a labs spokesperson said. “Despite the pause in enforcement, Sandia continues to encourage the small percentage of employees who remain unvaccinated to become fully vaccinated to create a safer workplace at the Labs and help deter community spread.”

Like the other two NNSA nuclear-weapons labs, Sandia says that 90% or more of its workforce is vaccinated. NNSA is the semiautonomous branch of the Department of Energy responsible for maintaining and modernizing U.S. nuclear warheads and bombs. Sandia does portions of the engineering and testing work to support nuclear designs maintained by the Los Alamos and Lawrence Livermore National Laboratories. 

Most NNSA site-operations contractors have paused enforcement of their COVID-19 vaccine mandates in the wake of a December injunction handed down by a federal judge in Georgia that blocked the Biden administration from enforcing its requirement that federal contractors get vaccinated or find new jobs.

Of the eight major NNSA nuclear-weapon sites, only Los Alamos and the Nevada National Security Site were still enforcing vaccine mandates as of Wednesday afternoon. The Savannah River Site’s management and operations contractor, which performs NNSA nuclear-weapons work at the former plutonium production site but is under contract with DoE’s Office of Environmental Management, also still required a vaccine. 

In court documents, Savannah River Nuclear Solutions has claimed it is a private employer and can require a vaccination whether its government customer demands one or not.