Emergency alerts are still broadcast via TV, radio and air siren, according to the Federal Emergency Management Agency. Arriving with distinct ringtones and vibrations, the wireless alerts resemble text messages when they pop up on cellphone screens, but they rely on different technology. There are three types of wireless alerts: those issued by the president; those involving imminent threats to safety or life; and Amber Alerts for missing children. PhotoThe system has come under growing scrutiny in recent months, with public safety officials complaining that it requires upgrades on several fronts. Last week, Mr. Pai announced a proposal to update the alert system to improve its location-targeting ability.

Source: New York Times January 14, 2018 01:33 UTC