The union representing radiographers is balloting its members on potential strike action.
Medical radiation technologists, also known as MRTs or radiographers, produce medical images of the body, using radiation, ultrasound or magnetic fields, to help doctors diagnose and treat illness.
The Association of Professional and Executive Employees (APEX) says district health boards have not budged from a zero pay offer since talks began between the parties in August.
The union says more is being demanded of radiographers and that must be recognised in their pay.
