Starting today, you can text to 911. All of the major wireless carriers in the US will make this available: Verizon, AT&T, Sprint, and T-Mobile. Hit the link below to get more details.
http://lifehacker.com/you-can-text-911-in-an-emergency-starting-tomorrow-1576457059
You can also go the to FCC site as well:
http://www.fcc.gov/text-to-911
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