Ambulance staff in South Yorkshire have staged a five-hour strike in the latest round of action over new shift patterns and will walk out again today.
Unite members at Yorkshire Ambulance Service NHS Trust have already held four strikes since 1 February, including one for five hours on Friday.
The union claims proposed longer shift patterns could lead to staff working for up to 10 hours without a meal break and could affect patient safety.
The trust said it had taken steps to maintain operational cover.
Unite represents about 375 of the trust’s 4,600 employees and is not recognised by the trust for the purposes of collective bargaining.
The union took industrial action for 24 hours on 1 February, four hours on 3 February and five hours on February 14 and 17.
Meanwhile, Unison has called off industrial action after reaching an agreement with YAS.
The union said the trust had met its demands over breaks and would review the use of emergency ambulances and rapid response vehicles.