Facebook has introduced a new feature to allow users to let their friends know they are safe if they are in an area affected by a disaster.

Named Safety Check, the tool allows the Facebook user to let their friends and family quickly know they are safe, check on others in the affected area, and mark friends as safe.

Facebook will determine whether someone is in the affected area based on the location listed on their profile, their last location and the place where they are using the internet. 

When there is a natural disaster and Safety Check is activated, those in the area will receive a notification that will allow them to quickly indicate if they are safe or outside the affected area. Friends will receive a notification when someone marks themselves as safe, and it will link to a shortcut of their latest updates.

Safety Check is a continuation of the Disaster Message Board feature built by Facebook's Japanese engineers following the 2011 tsunami and earthquake in their country.

Announcing the new project, Mark Zuckerberg said, "it's meaningful to be in Tokyo to announce this because the great earthquake and tsunami a few years ago inspired us to build the first version of this for Japan. Now we're glad to have this ready to serve everyone in the world".

You can see a video of how the feature works below:

Introducing Safety Check from Facebook on Vimeo