Essex Ambulance Service is launching a new fleet of major incident vehicles.
The vans are based at strategic locations around the county and eight of nine ordered have been delivered.
The last was due to become operational at the end of September. They include vans designed for chemical incidents whether accidental or deliberate.
Also included are vans which carry shower units for decontaminating casualties and the personal protection equipment which staff could be using.
The fleet includes vehicles fitted with a deployable mast that has the ability to run complex radio communications and can replace the main operations centre at headquarters if it cannot be used for any reason.
Incident Support Unit Manager, Shaun Downes, said: "After the terrorist attacks on 11 September, we fully reviewed our major incident fleet and equipment supplies.
"We identified that we needed to be better prepared and these vehicle allow us to do that.
"This is a major step forward for the service. It gives our staff the best equipment available and a good level of working conditions should the worst ever happen."
Chief Executive of Essex Strategic Health Authority, Terry Hanafin, formally launched the vehicles at a ceremony at Ambulance Headquarters in Chelmsford.
He said: "The new fleet of major incident vehicles should reassure the public in Essex that the NHS is geared up to cope with a major emergency.
"We sincerely hope they are never put to use, but at the same time they provide emergency staff with modern, first-rate equipment, should it be required."