Blood-testing staff at three West Yorkshire hospitals will strike for 48 hours this week over patient safety.
Hospital pathologists, who test blood samples and monitor blood transfusions, will stage a walk-out at St James’ Hospital in Leeds, and Leeds and Bradford Infirmaries on Thursday and Friday.
It comes after a strike on July 16 over proposed changes to working patterns by the Leeds Teaching Hospitals NHS Trust.
The country’s largest union, Unite, said the Trust's plans put staff and patient safety at risk and could mean significant pay cuts of up to £20,000 a year for workers.
Talks have been held to try to settle the dispute, which affects 140 staff, but union members say no progress has yet been made.
Unite regional officer Terry Cunliffe said: “We had offered to reconsider this week’s industrial action if the trust withdrew the threat to impose these shifts on our members, but...it has refused.
“We have a duty to fight such proposals and to bring this issue to the attention of the public," he added.
The strike will begin at 8.30am on Thursday and continue on Friday."