Firefighters in Hertfordshire are to take part in industrial action over pensions next month, the Fire Brigades Union has announced.
Firefighters will strike between noon and 5pm on May 2; between 2pm and 2am on May 3 and on May 4 between 10am and 3pm.
There will also be a ban on voluntary overtime across England and Wales from 3pm on May 4 until noon on May 9.
Hertfordshire Fire Brigade Union secretary Tony Smith said: "The Government has failed to make any offer since the last strikes. We have been talking for months discussing all sorts of angles and ways and we have tried to negotiate. We are very disappointed about this.
"This is the only option left to us. Obviously it is the last thing we want to do but we have to make a statement. We are hoping that this announcement will cause the Government to act."