only during medical emergencies but also daily to further independence and access to services. For people with disabilities who are unable to drive themselves, mobile devices can be imperative in arranging for transportation. Indeed, the penetration of wireless devices in communities of people who have disabilities is the same, if not slightly higher, than in the community at large.

This finding, and the observation that text messages are increasingly used to deliver alerts and warnings, prompted the Wireless RERC to conduct a series of field trials, focus groups, and simulations to investigate a variety of approaches to delivering text alerts. The study population was primarily individuals who are blind or have low vision, or who are deaf or hard of hearing, along with a few participants with cognitive disabilities; the study population included people with varying levels of technical savvy. The tests used two different devices: (1) a Windows mobile device with custom software to provide a tone alert similar to that used in the Emergency Alert System (EAS), other customized attention signals, and text-to-speech processing; and (2) standard BlackBerry devices that support text messaging and are commonly used in the community of people who are deaf and hard of hearing.

The Wireless RERC studies were completed before an initial set of requirements for the CMAS program was set forth by the 2007 Commercial Mobile Service Alert Advisory Committee (CMSAAC) report.1 The studies used a standard short message service (SMS) text message and a Web page, putting essential information in the SMS body and including a hyperlink to the full alert on the Web page. The first test group, composed of people who are blind and vision-impaired, used the custom device. These test subjects found that the tone alerts and speech synthesis were a significant improvement over the phones that they normally used. The second test group, composed primarily of people who are deaf and hard of hearing, used the BlackBerries. They found the text message alerts to be useful but not a big improvement over the systems that they normally used. For example, many in this group already subscribed to alerts from third-party providers such as the Weather Channel. For them, the EAS-like alert was slightly preferred because it provided somewhat more detailed information and did not contain advertisements. Notably, in post–field surveys, 83 percent of people with sensory limitations said that receiving emergency alerts by way of wireless devices was highly desirable.

After the 2008 adoption of the CMSAAC recommendations by the FCC, Wireless RERC conducted a second series of tests using CMAS-like messages (90-character messages that did not contain links to second-


CMSAAC, PMG-0035, 2007; and FCC, Public Safety Docket No. 07-287.

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