The fire station in Chelmsford could be used as a hub for ambulances to improve response times.
East of England Ambulance crews will use Frinton and Old Harlow fire stations as part of a three-month pilot scheme from mid January.
If successful the approach will be rolled out later in 2015 to Chelmsford fire station, in Waterhouse Lane, as well as Colchester and Waltham Abbey.
"The facility allows the ambulance service to have more people in the right place when they are needed and should get ambulances to people quicker," explained assistant divisional officer Mark Wilby, Essex County Fire & Rescue Service project manager.
"The pilot is simply an extension of ECFRS' commitment to strengthening partnerships and shared services with other blue lights services.
"Firefighters very often work alongside ambulance teams at the scene of road traffic collisions and by providing ambulance colleagues with a bolt hole, there will be the positive practical benefits but also the move should help to develop relationships on the ground and potentially lead to greater understanding and potentially further down the line joint training and information sharing.
Ambulance crews will be allocated an identified hatched area located on ECFRS station forecourts between 6am and 2am and will turn out during these times to emergency calls with an additional advantage of the crews being able to use fire station toilet facilities, rest areas and take on light refreshments.
If they respond to a 999 call, then another ambulance or paramedic vehicle will be redeployed to take its place.
"This is not about replacing ambulance stations," ADO Wilby added.
"Ambulance crews will still pick up their vehicles, do their safety checks, paperwork and daily business routines back at base
