A mass notification system sends one alert to many channels at once: phones, email, desktop pop-ups, sirens, public address and screens. Adding screens as a channel reaches the people who aren't looking at a phone, such as visitors, students in a corridor or staff on a plant floor.
Who uses it
Campuses, hospitals, plants, government buildings and large offices. Organizations that already run a mass notification platform (Everbridge, Rave, Alertus and Singlewire are common ones) usually want screens on the same button, so one decision reaches everyone.
Some duties make screens part of the record. US colleges under the Clery Act have to issue emergency notifications and test their procedures each year, with the tests documented; screens that show the alert, and a record that they did, help with both.
How an alert reaches screens
| Route | How it works |
|---|---|
| CAP | The alerting system publishes the alert in the Common Alerting Protocol, and the signage system reads it |
| A connector | The two products have a built-in integration |
| API or webhook | The alerting system calls the signage system's API to start and stop an emergency message |
What the screens have to do
- Take over at once, ahead of everything else scheduled, on the screens in the affected area only.
- Show the message large enough to read across a room.
- Keep showing it if the network drops.
- Clear when the alert ends, without a person remembering to undo it.
- Leave a record of what played, for the drill log and the after-action review.
- Stay quiet otherwise: a takeover that fires by mistake is its own incident.
What to ask a signage vendor
- Does it connect to our mass notification system, and how?
- Can an alert target some screens and not others?
- How fast does a takeover reach every screen?
- What happens on screens that are offline when the alert is sent?
- Who can trigger a takeover, and is it logged?
Where Screenly stands
Screenly has no built-in connector to a mass notification system. Its takeover is the priority playlist: it replaces everything else on the screens you choose, by label, site or workspace, and hands back on its own when its schedule ends. Everything in the dashboard is in the API, so the alerting system can switch it on. ScreenlyOS devices keep playing from local storage if the network drops, and proof of play records what played, on request. CAP alerts covers the alert format.
