Here's the latest breakdown of the more commonly used emergency alert systems. Deploying multiple modes will help to ensure the strengths of one solution compensate for the weaknesses of others.
Solutions covered include call boxes, digital displays, E-mail, intercoms, loudspeakers and Giant Voice, phone trees/telephony, computer pop-up messaging, sirens, text (SMS) messaging, voice evacuation systems, weather radios, Web site announcements and hotlines.
Many of these solutions can now be linked with each other so messages can reach more individuals on or near a campus, as well as other stakeholders, such as family members.
Be certain to test the systems regularly, and account for the hearing and sight impaired.
View the 2010 Mass Notification Cheat Sheet.
For information on bullhorns, common alerting protocols (CAP/IPAWS), digital communication spectrum (digital television feeds), posters, radio announcements, RSS feeds/readers and smart phone apps, click here.