For many Hawaii residents, the ballistic missile false alarm was a preparedness wakeup call.

State officials have been trying to tell residents for months that if there is a missile headed for the islands, there will be little time to do much more than to get inside, stay inside and stay tuned. But that message didn't seem to sink in until after the false alarm.

Residents and tourists remained rattled Sunday, a day after the mistaken alert was blasted out to cellphones across the islands with a warning to seek immediate shelter.

The chairman of the Federal Communications Commission says it appears the Hawaii government didn't have reasonable safeguards in place that would have prevented the transmission of a false alert.