The Defense Department on Monday issued an order barring all personnel from using geolocation services on their personal and government-issued devices in all “operational areas.”

The policy, which applies to smartphones, tablets, fitness trackers, smartwatches and all other applications with geolocation features, goes into effect immediately.

“The rapidly evolving market of devices, applications, and services with geolocation capabilities … presents significant risk to Department of Defense personnel both on- and off-duty, and to our military operations globally,” Deputy Defense Secretary Patrick Shanahan wrote Friday in a memo to top Pentagon brass.

“These geolocation capabilities can expose personal information, locations, routines and numbers of DoD personnel,” he said, which can create “unintended security consequences and increased risk to the joint force and mission.”

Under the new measure, combatant commanders in operational areas can make exceptions for certain government-issued devices based on “mission necessity.” They can also permit the use of geolocation services on personal devices after conducting a comprehensive operations security survey.

The Pentagon defines an operational area as “a location where military are operating for the purposes of a specific mission,” Pentagon spokesperson Maj. Audricia Harris told Nextgov. Overseas military outposts, such as those used in the fight against ISIS, would fall under this umbrella, she said, but the Pentagon building would not.  

Though the order doesn’t block geolocation services in non-operational areas, it requires officials to assess the risks of those features for on- and off-duty personnel and issue “rational” restrictions when they pose a threat to employees or operations.

“The goal of this policy is to focus more on the features instead of the devices,” Harris said, noting geolocation services are becoming almost ubiquitous as more products connect to the internet. “Next thing you know there might be contact [lenses] with the same capability, so we want to focus on the feature and not the actual medium.

The measure comes as the Pentagon’s latest crackdown on the use of electronic devices at department facilities.

In May, Shanahan issued a sweeping ban on personal and government-issued mobile devices in classified areas of the Pentagon, citing concerns over potential leaks of classified information. The ban doesn’t cover devices with negligible storage and transmission capabilities, like key fobs.

The Pentagon began reconsidering its mobile electronics policies after the fitness-tracking app Strava compiled user location data in a global heat map and inadvertently revealed the locations of multiple overseas military bases. The data dump also publicized the identities and locations of international aid workers, intelligence operatives and military personnel, raising security concerns among government officials.

“We’re always aware of the rapidly changing technological environment so we’re always looking at our policies to make sure they’re up-to-date and that they continue to protect the integrity of our mission and our personnel,” Harris said.