The Unison union is calling on the Tees, Esk and Wear Valley NHS trust to halt its plans to hand hundreds of NHS staff over to a wholly-owned subsidiary company.
A similar scheme led to strikes in Wigan.
The trust’s plans involve transferring 600 members of staff to a private company it has set up, called Tees, Esk and Wear Valleys Estates FM Ltd. Maintenance workers, porters, housekeepers and caterers would be among those affected.
Many of the workers who face being transferred out of direct NHS employment have worked for the health service for more than 20 years.
The union has written to the trust, along with local Labour MPs from the Tees Valley, calling for an end to the proposals.
The letter warned that privatisation does not work in the interest of patients or staff, and cited the recent collapse of outsourcer Carillion.
The union has launched a petition urging the trust not to go ahead with the privatisation, which has already been signed by staff and local people.
Further meetings with staff will take place in the next few weeks ahead of a trust board meeting on 25 September.
Salisbury NHS trust is also trying to transfer its support staff to a wholly-owned subsidiary private company.
Staff at Salisbury District Hospital learned of the proposals this week, in a series of meetings that kicked off a month-long consultation over the plans.
The move will affect some 375 health workers including porters, switchboard operators and couriers.
Bolton hospital strike over pay
Around 650 cleaners, catering staff, porters and security officers at the Royal Bolton Hospital are voting on a strike over pay.
Local health bosses have decided not to pay the wage increase agreed nationally for NHS workers.
The workers being balloted are employed by Integrated Facilities Management Bolton Ltd—a wholly-owned subsidiary of Bolton NHS foundation trust.
Workers planned to lobby a company board meeting on Tuesday this week. Their Unison union said they could strike.