Queensland prison officers are striking after wage negotiations broke down.

A series of half-day strikes began on Wednesday afternoon at prisons across the state, the Together union says.

Union secretary Alex Scott saus Queensland Corrective Services (QCS) has sought to undercut award conditions and introduce a “risky” flexible staffing policy that he alleges would compromise security and safety.

“These issues for members are far more important than wages,” he told AAP.

“What was a debate [on Tuesday] about wages has now become an issue about the safety of the community and our members through a fundamental change to the way correctional centres are managed.”

The protected industrial action comes after three months of stalled QCS wage negotiations.

QCS said affected jails would be placed into lockdown when officers walk off.

“Prisoners will receive meals and medications as needed during this time,” a spokeswoman said in a statement.

“Contingency plans are in place should there be an incident at the centres during the lockdowns.”