Dingtone does not carry emergency call.
Based on the statement in "Terms of Service" provided by Dingtone:
The Software (Dingtone) does not and is not intended to support or carry emergency calls to any type of hospitals, law enforcement agencies, medical care unit or any type of emergency services of any kind and Dingtone is not liable in any manner for such calls.
Therefore, don’t depend on Dingtone in the case of emergency.