Ensure the availability of emergency numbers

A major advantage of Voice over IP is that the connection can be used worldwide, regardless of the connection address. However, this can lead to problems with emergency calls, because

• the transmitted telephone number determines which emergency call centre is responsible.
• If no location details can be provided during an emergency call (e.g. a ‘gasping for breath’ call), the connection address associated with the phone number is determined. Emergency services will then be dispatched to this address.

However, to ensure that the correct address can be identified in an emergency, you should only make emergency calls from a line registered to the address where you are currently located. 

• If you are working remotely, please use your mobile number to make an emergency call.
• If you are working from home, please use your private landline or your mobile number for emergency calls, rather than your office number.

Individual caller ID information does not usually have a direct influence on which emergency call centre is selected. The location data on file with the provider is the decisive factor.

However, it is important that the number provided is reachable so that the emergency call centre can call back.

In many telephone systems, emergency numbers can be defined so that they are handled separately. Some or even all of the points in this article will then be implemented automatically.

If in doubt, you should check with the manufacturer to find out whether, and to what extent, your telephone system supports this function.

For the call to go through, both parties must agree on a codec. In the case of Voice over IP, it has been agreed that emergency call centres must accept the G.711A codec (see Framework for Emergency Calling Using Internet Multimedia).

Please therefore ensure that G.711A is correctly configured and available in your telephone system.

Most telephone systems on the market first check for internal numbers or speed dials when routing calls. Only then is the call routed externally to the relevant provider.

If, for example, 122, 133 or 144 were assigned as internal speed dials, all emergency calls would be routed to the relevant extension rather than to the emergency services. For this reason, our Cloud PBX does not allow 122, 133 and 144 to be assigned as internal speed dials at all.

Telephone systems often modify telephone numbers before passing them on to the service provider. A common example of this is when the country code and area code are automatically added to the start of a number if they have not been dialled.

It is therefore essential to ensure that emergency numbers such as 122, 133 and 144 are always transmitted directly and unaltered to the outside network. This is automatically guaranteed in Easybell’s Cloud PBX.