The furloughs, which were ordered by Secretary of Defense Chuck Hagel to meet mandated budget cuts forced by the sequester, will affect more than 650,000 civilian defense workers.
Last week, a coalition of federal employee unions launched a campaign to stop the Pentagon from imposing the furloughs, which they say unfairly target defense workers.
While many federal agencies have avoided furloughs, the Defense Department decided it could not meet the mandated cuts without them. The furloughs are projected to save the Defense Department $1.8 billion, according to officials.
Furloughed workers are prohibited from performing any work-related assignments while away from their jobs.
Most furloughed employees face one day without pay for each week through the end of September.
“Employees may request a specific furlough schedule; however, the department’s approach has generally been one day a week, two days per pay period not to exceed a total of 88 hours,” said Navy Cmdr. Leslie Hull-Ryde, a Defense Department spokeswoman.