404 Tech Support

What is the Commercial Mobile Alert System (CMAS)?

In an update released to my wife’s phone today, the changelog listed the Commercial Alert System (CMAS) being activated. With a name like that and little elaboration, I had to do a little research to find out what it meant.

Fortunately, the FCC had the answer on their website to explain it.

The FCC took a number of steps in facilitating the ability of consumers to receive emergency alerts through their wireless phones. In 2008, the Commission issued a series of orders adopting requirements for a Commercial Mobile Alert System (CMAS), a system by which commercial mobile service (CMS) providers may transmit emergency alerts to their subscribers, if they choose to do so.

So, it’s an alert system that the carriers (Sprint, AT&T, Verizon, T-Mobile, etc.) can use to notify customers in an area of an emergency, established by FEMA and the FCC. I’ll admit that my first thought was that Sprint was going to start sending ads (commercials) to the phone as notifications.

You can read the full rules at the FCC page but I’ll highlight a few of them:

According to the FCC Master CMAS Registry, amongst smaller carriers US Cellular is participating ‘in whole’ while AT&T, Verizon, T-Mobile, and Sprint Nextel are listed as participating ‘in part’. As for what ‘in part’ means, that seems to be a bit more hidden.