Paris Attack: How Facebook 'Safety Check' Feature Works

Updated: November 14, 2015 12:45 PM [ET] | Originally published: November 14, 2015 8:43 AM EST;

After Friday night’s terrorist attacks in Paris, you may have noticed an unusual notification appear on Facebook for the first time: “[Friend’s Name] was marked safe during Paris Terror Attacks.”

The notifications came from a Facebook feature called Safety Check. If you’re in an area struck by some kind of life-threatening situation, Safety Check will prompt you to tell your Facebook friends you’re safe. To figure out your location, the feature looks at several data points, including your profile data, your last location (if you let Facebook see that information) and the city from where you’re connected to the Internet.

TIME’s Naina Bajekal reports from Paris the company sent her a text message asking to confirm her status during Friday’s attacks — text messages will often work even when full Internet access isn’t available.

Unlike a normal Facebook update, using Safety Check will instantly blast your status to your friends in the form of a notification. That’s a smart touch — this reporter received at least one such notification Friday from a friend he didn’t even know was in the area.

If you’re with other people, you can also mark them as safe. That’s handy if they don’t have the means to access their Facebook account in the midst of a chaotic or dangerous situation.

Facebook introduced Safety Check last year, inspired by an employee project built in the wake of the devastating tsunami that struck Japan in 2011. It was initially envisioned as a tool to use during natural disasters, like earthquakes or hurricanes. It’s been activated several times already for those incidents: I was notified of a friend’s safety following an earthquake in Afghanistan; the feature was also activated in April after a similar disaster in Nepal.

But Paris is the first time Safety Check was deployed during a terrorist attack.

“We are shocked and saddened by the events unfolding in Paris,” a Facebook spokesperson says. “Communication is critical in these moments both for people there and for their friends and families anxious for news. People turn to Facebook to check on loved ones and get updates which is why we created Safety Check and why we have activated it today for people in Paris.”

Witness Paris Mourn the Day After Deadly Attacks

The Eiffel Tower turns off its lights in memory of the more than 120 victims the day after the terrorist attack on Nov. 14, 2015 in Paris.Marc Piasecki—Getty Images

Bono and band members from the band U2 place flowers on the pavement near the scene of yesterday's Bataclan Theatre terrorist attack on Nov. 14, 2015 in Paris.Jeff J Mitchell—Getty Images

A woman is comforted by others outside the Carillon cafe and the Petit Cambodge restaurant in Paris on Nov. 14, 2015.Jerome Delay—AP

France Paris Attacks — A man places a candle in front of the Carillon cafe in Paris, on Nov. 14, 2015.Jerome Delay—AP

Significant Death Toll Feared In Paris Terror Attacks — The interior of the Casa Nostra Cafe, the day after the attacks on the city, on Nov. 14, 2015 in Paris.Christopher Furlong—Getty Images

Dozens of burnt motorbikes and bikes are pictured on the corner of Albert Thomas Lancry streets, in the 10th arrondissement of Paris, on November 14, 2015, few hours after a series of terror attacks that occurred across the city. ©MAXIME JOUY/NEWZULU/Al — Burnt motorbikes and bicycles on the corner of Albert Thomas Lancry streets, in the 10th arrondissement of Paris, on Nov. 14, 2015, the morning after the attacks across the city.Maxime Jouy—Newzulu/Alamy Live News

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