A multi-agency exercise with police and the emergency services is due to take place in Derbyshire.
The exercise, this week, will involve the emergency services, local authorities and a variety of other agencies including members of the armed forces.
It is based on a serious emergency or major incident where local emergency responders need help to deal with the event and its consequences.
Most of the activity is taking place at police headquarters in Ripley.
However, there may be some locations in North Derbyshire where responders come together to make joint decisions about a hypothetical emergency scenario, involving flooding.
Assistant Chief Constable Gary Knighton, who is in charge of emergency planning for the police, said: “Thankfully major emergencies are rare, but when they do occur they require a co‑ordinated approach from many organisations.
“This is why we practice and test our plans on a regular basis.”
Councillor Dave Allen, Derbyshire County Council’s cabinet member for health and communities, said: “This exercise is routine testing for our emergency planning personnel and there is no reason for any residents to be alarmed by the activity they may see.
“It’s important that we provide the best possible service to the people of Derbyshire if we are faced with a major incident. In emergency situations we often rely on the support of the voluntary sector and volunteers will also be involved in this exercise.
“I’d like to take the opportunity to thank them for giving their time so willingly.”