When a 999 call is made from residential or business premises using a phone that is directly connected to the public telephone network precise location information for the caller is automatically displayed to the BT (or Cable & Wireless) 999 operator.
However, if a 999 call is made from an office telephone system (ie PBX) extension there is a significant risk that the location information presented to the 999 operator will be misleading, particularly with the latest generation of IP-PBXs.
The reason for this is that the BT (or Cable & Wireless) 999 location database is provisioned only with location information for the point where the call leaves the PBX and enters the public telephone network.
This is not ideal if the caller is in a large office block, a dispersed factory site or in a multi-building campus that is served by a PBX with thousands of extensions.
In a multi-site network with a single PBX server at head-office, or the company data-centre, the caller may even be at a completely different geographic location.
It is this latter possibility that causes most concern since centralised break-out of external calls from a single PBX server is a key feature of the latest IP-PBX telephone systems.
The availability of location information is vital if the 999 operator is unable to obtain verbal confirmation of the caller’s location. This may be due to:
- the nature of the emergency (eg smoke inhalation or physical danger);
- language, accent or dialect issues; or
- the fact that the caller may be simply unaware of their precise location or be disoriented.
The following pages examine this issue both from a legal and technical angle and then describe solutions that will ensure that employees and visitors to business premises served by PBX telephone systems have the same level of protection as 999 callers from residential or small business premises.