Estates workers in NHS Tayside are going on strike from Wednesday, as they extend their industrial action in a dispute over pay and conditions.
Unite says its members will now go on strike for three days each week, in addition to withdrawing weekend cover.
Earlier, the workers had agreed to strike for two days each week as they called for the implementation of national conditions for craft workers.
The dispute involves around 60 estates workers including electricians, joiners, and plumbers.
The extension of the strike days means they will not return to work until 8am on Monday.
NHS Tayside has earlier said the dispute affects only the estates department at Ninewells Hospital in Dundee and there will be no impact on patient care.
The health board said it had already agreed to halt a staff restructure proposed earlier this year.
Sharon Graham, Unite general secretary, said: “Unite has sought to resolve this dispute through negotiation and arbitration but NHS Tayside is refusing to listen to anyone but themselves.
“They have left our members with no option but to escalate their industrial action.
“Our members are determined to get what they deserve – fair and equal treatment – and Unite will continue to support our members all the way.”
NHS Tayside said it believed a dispute with Unite had been resolved in July, and was “disappointed” at industrial action at Ninewells Hospital.
A spokesperson for NHS Tayside said: “We are extremely disappointed that Unite are escalating their industrial action. We have contingency arrangements in place. Throughout the strike action which has been running since the end of September, no clinical activity has been affected.
“We are dismayed at some of the statements made by Unite which are not reflective of what is happening in Ninewells or other parts of the NHS Tayside estate.
“The contingency arrangements means there have been no concerns relating to building environments across the NHS Tayside estate. There has been no widespread heating or hot water issues in any areas reported by clinical or estates teams. Any maintenance issues reported are being dealt with as normal.
“NHS Tayside has proactively contacted Unite throughout the dispute several times in the past week to continue discussions. Management met with staff last week in an open question and answer session in which many questions were raised and responded to in relation to the dispute.
“NHS Tayside remains committed to resolving the dispute and believes that there are still routes for resolution open to both parties.
“One of these routes to local resolution is the offer which has been made to both Unite and individual members of staff to bring concerns they have relating to their pay to their managers or other senior leaders with a commitment these will be fully investigated.”
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