National Audit Office (NAO) has warned that the planned implementation of the Emergency Services Network (ESN)

National Audit Office (NAO) has warned that the planned implementation of the Emergency Services Network (ESN)

The National Audit Office (NAO) has released its report on the transition of the “Blue Light” services (police, fire, ambulance etc.) from the current Airwave UHF TETRA system to the commercial 4G network provided by EE/BT.

Whereas the NAO acknowledges that a transition to the 4G Emergency Services network offers many advantages such as the ability to provide access to high-speed data and ultimate cost savings when compared with Airwave’s TETRA network, it questions whether the time-frame adopted by the UK government for implementation is realistic. At present the transition to the 4G network is scheduled to commence on a region-by-region basis starting September 2017 and to be completed by December 2019.


Factors influencing its conclusions include:

  • EE/BT’s network currently cover 70% of the UK land-mass compared with 97% covered by Airwave. Therefore additional base-station sites will need to be established;
  • Devices for 4G do not currently incorporate features demanded by many of the User services, such as push-to-talk and direct device-to-device communication capabilities;
  • Development required for new software to permit push-to-talk and device-to-device communications;
  • Development of software and protocols are needed that would enable “Blue Light” services to have priority over commercial users of the EE/BT network.


The NAO does acknowledge that these factors are not necessarily insurmountable, but expresses concern regarding whether they can be overcome within the time-frame proposed. It also warns that the transition is a high-risk programme, and points out that at present only South Korea is proposing a similar transition to 4G but that it starts out with significantly better system coverage. Other countries looking at enhancing their emergency communications systems are adopting a “wait-and-see” approach by proposing to initially use only data services on 4G and retain their existing voice communications systems (using TETRA, P25, or similar protocols) until industry has developed suitable hardware and software.