safety check

https://static.xx.fbcdn.net/rsrc.php/v2/y-/r/CpZ8KuL2u35.png

 safety check  is an aggregation feature that shows a list of the people you follow in a disaster affected geographical area that have marked themselves as safe; like Facebook does at https://www.facebook.com/safetycheck.

Facebook
Facebook has a Safety Check page: which redirects to a subpage of that URL of the most recent disaster worldwide that Facebook is tracking and aggregating safety information for.
 * https://www.facebook.com/safetycheck

2016-07-14 screenshot of a FB Safety Check:



2015-11-13 Text-ish summary of Facebook's Safety Check:  ABOUT THE CRISIS map of affected area with large blue translucent circle over the epicenter text description of disaster https://static.xx.fbcdn.net/rsrc.php/v2/y-/r/CpZ8KuL2u35.png Disaster Event Name FACEBOOK SAFETY CHECK Quickly find and connect with friends in the area. Mark them safe if you know they're OK. Are you in the affected area? Yes, let my friends know.

Note also list of people, some with buttons next to their names:
 * Ask If Safe
 * Mark Safe