DEC112 – The PSAP Interface

DEC112 – The PSAP Interface

13. August 2018 Off By dec112

Receiving emergency text messages at a PSAP is different to plain emergency calls but must be integrated in the same workflow of a control center. Depending on the capabilities of the PSAP system this might be a bit challenging …

In our recent blogs the DEC112 architecture and core elements for mapping and routing were introduced. One important element is still missing – the emergency control center or public safety answering point (PSAP). Depending on country specific requirements it may either be a single control center answering calls to an emergency telephone number for police, firefighting, and ambulance services (9-1-1 in the US), or each agency runs its own control center (122, 133, 144, … in Austria). We already explained how to route calls or, in the case of DEC112, messages to the most applicable PSAP, but how does a PSAP receive such messages?

Basically, at a control center, two main tasks can be distinguished: call taking and dispatching. Call taking is, in technical terms answering the emergency call by a well-trained operator or call taker. Dispatching, in short, is announcing the call details to field units via data messages or over a two-way radio. A call taker’s task is far more complex by nature, requires analytical skills, multi-tasking, interpersonal and crisis management skills – but let’s focus on the technical part.

In the case an emergency call arrives at the PSAP, it gets routed through a call processing equipment (CPE). The CPE may utilize an automatic call distribution (ACD) algorithm to forward the call to the next free call taker. Further, first information of the calling party is shared with the computer aided dispatch (CAD) system. As soon as all relevant incident data is collected, the proper units are dispatched to the incident.

Text messages are quite different to a plain voice call but must be integrated in the same workflow, which, depending on the capabilities of the PSAP system, might be a bit challenging. If either the CPE or the CAD provide interfaces to external communication sources and support the reception of a so-called trigger message, it would be possible to indicate an incoming DEC112 message on a call takers position. But how would a call taker be able to chat with the person in need? The following gives an example how to integrate, but there might also be different options.

One of the DEC112 work packages aim it to integrate with different emergency control center systems. Based on the workflow explained above, we decided to move on with the following ideas:

  • Implement a kind of PSAP border device or gateway connecting to the DEC112 service entities
  • The border device creates a trigger message (adaptable to local needs) if a message arrives
  • The trigger message contains among others, location, reference data and an URL pointing to a local Web-UI with chat features
  • The PSAP CPE or CAD receiving the trigger just needs to support a web object in the call takers UI, that automatically connects the border device via the URL given
  • In the case, such an integration is impossible, DEC112 provides a web-based UI to display location, reference data and chat features that can be accessed via a browser

Recently, this task has been completed and currently the first emergency control center is integration and testing this solution. Further technical details and screenshots can be found in the following blog.