 The service can also, if required, mobilise London's Air Ambulance and even the Kent, Surrey and Sussex Air Ambulance if there is a major incident requiring more than one critical care team, and where other teams in the region are operating at maximum capacity.The trauma teams are dispatched by a Critical Care Paramedic at the Critical Care Desk, in their Control Room in Chelmsford, who filters through every call the ambulance service receives and makes a clinical decision on whether to dispatch a critical care resource.The trust was formed on 1 July 2006 following the three-way merger of the Bedfordshire and Hertfordshire Ambulance Service NHS Trust, the East Anglian Ambulance NHS Trust and the Essex Ambulance Service NHS Trust.