Federal Emergency Management Agency

Twitter said Wednesday morning it has launched Alerts, a new system designed to help users get crucial information in the event of an emergency.

Following on Twitter's implementation of a similar system called Lifeline in Japan last year, Alerts is meant to deliver the most important -- and accurate -- information from "credible organizations during emergencies, natural disasters or moments when other communications services aren't accessible."

The new system makes sense because Twitter is already seen by many users as the most reliable way to get real-time information about breaking news, emergencies, and other events. Giving users a way to get the most reliable information from the most credible agencies is a natural extension of that common use case.

If you sign up to receive an account's Twitter Alerts, you will receive a notification directly to your phone whenever that account marks a tweet as an alert. Notifications are delivered via SMS, and if you use Twitter for iPhone or Twitter for Android, you'll also receive a push notification. Alerts also appear differently on your home timeline from regular tweets; they will be indicated with an orange bell.

The system is meant to allow users to sign up for alerts from a wide variety of public and private organizations that would be putting out critical information via tweets during an emergency. Users have to opt in for alerts from each such agency. So, for example, to get alerts from the Federal Emergency Management Agency, a user would need to go to FEMA's Alerts page and click on the "Activate Alerts from @fema" button.

Twitter has so far added a variety of national and local organizations in the United States, Japan, and Korea. In the US, those include the American Red Cross, the Centers for Disease Control and Prevention, the US Department of Homeland Security, and many others. Twitter said it will add more agencies over time.