ary sources) and alerting by means of a distinctive tone and vibration cadence. About three-quarters of those who had participated in previous tests thought that this CMAS-like alert was an improvement over the third-party alerts with which they were familiar. They observed that CMAS-like messages were simple and that they clearly indicated what action to take, but these people suggested that it would be useful if links to supplemental information were included.
Text alerts are inherently ill suited for people who are blind unless the telephone that they are using has the ability to read the text—that is, has text-to-speech capabilities. Without the inclusion of text-to-speech capabilities, CMAS-like messages simply cannot be used by those who are blind. Moreover, there are questions about the more general usability of cell phones by people who are blind—the phones that they commonly employ fall into two categories. The first category consists of much older telephones with fewer features and settings and thus very simple interfaces that can readily be memorized. However, these older phones cannot receive CMAS messages, and it is unclear whether new phones that do support CMAS will be simple enough to be used by those who are blind. The second category consists of new smartphones that have built-in voice commands and voice menus. Today, these capabilities are only found on high-end smartphones, which may be too expensive for many.
Fortunately, there are several resources for emergency alerting that already exist for those who have a hearing impairment. E-mail and SMS alerting systems are already understood to work well. Television coverage of emergencies provides a great deal of text and visual graphics, so that even those who cannot hear what is being said can glean at least some of the needed information from the media coverage. There are National Oceanic and Atmospheric Administration (NOAA) weather radios with text displays, flashing lights to garner attention, and vibration functions to awaken a person. However, the content of the text component is much more limited than the audio (speech) information that is broadcast to the radios. Telephone emergency notification systems are not particularly useful for those with impaired hearing, as fewer people with impaired hearing have a land line, and most telephone alerting systems do not provide a TTY option, which would allow a person who is deaf to receive the calls