America's ability to interact online and use mobile technology have changed significantly since Sept. 11, with the use of social media such as Facebook and Twitter playing a greater role in disaster response and preparedness.

Hospitals and public health organizations are increasingly using social media to get the word out during a crisis and are finding at times that tools such as text messaging, Facebook and Twitter may be their only options.

During Hurricane Irene last month, 135-bed Carteret General Hospital, Morehead City, N.C., was able to post regularly to its Facebook page and Twitter feeds despite at times not having regular power or regular telephone access.

“All I can say is smartphones are a wonderful thing,” says Michelle Lee, who as marketing and public relations director was responsible for the updates. Lee says she was not on the hospital premises but was in direct contact with Carteret's storm command center using the hospital's e-mail and her smartphone as the hospital ran on generator-produced power. (She says the hospital's disaster communications were operable even though its main phone system was not.)

Carteret executives studied the market in May and found that Facebook was used more often than Twitter in the community but both tools were used for messaging during the storm.

“We saw this as a new means of communicating when the other ways aren't working,” she says.

On a much broader scale, the American Red Cross has ramped up its use of Facebook and Twitter during calamities such as Hurricane Irene, and is increasingly using Twitter chatter in its disaster-management assessments, says Wendy Harman, director of social strategy for the American Red Cross in Washington.

The Red Cross had at least one volunteer working on monitoring messages and publishing on social media beginning two days before the storm made landfall Aug. 27 in North Carolina and relied on storm-related Twitter postings for its analysis of the effects of the storm, “That situational awareness is becoming more important to us,” Harman says.

And that's a trend Americans are happy to see, according to recent surveys. Two surveys together found that 80% of the general public and 69% of the online population “believe that national emergency response organizations should regularly monitor social media sites in order to respond promptly,” according to a news release from the Red Cross.

The results also showed relatively high use of social media, text messaging and online news sources by the public during times of disaster. The surveys indicate that 24% of the general population and 31% of the online population would use social media to tell family and friends they are safe.