The EAS is the Emergency Alert System which replaced the Embergency Broadcast System in the mid-90s.
As a sidenote, it is amazing that the EAS was no activated here in the DC area during the 9/11 attacks. But it was activated for the 9/24/01 College Park tornado and subsequent tornado and severe storm outbreaks this year...
I remember being in DC then. Being gainfully unemployed at the time, I slept through the whole thing. I remember thinking "why didn't that air-raid siren thing they set off every Wednesday at noon go off?
Expressing myself EVERY day - but especially on July 22, 2002!
900 gives a +/- error rate of 4% for the nation I think. Meaning, essentially, that there is a 95% certainty that the actual number lies somewhere between 4% higher and 4% lower than the polled number.