Mental health: Ysbyty Gwynedd's Hergest Unit could lose beds
Some beds at a mental health unit in Bangor could temporarily close to try and deal with concerns over the way patients are treated.
Staff at Ysbyty Gwynedd's Hergest Unit have criticised the plans, blaming problems on managers.
Last year, Healthcare Inspectorate Wales (HIW) identified low staff morale and other issues in a surprise visit.
Betsi Cadwaladr University Health Board (BCUHB) said fewer beds would help it address some of the issues.
Health service regulator HIW made a surprise visit to the 42-bed Hergest Unit at the end of last year.
Its report criticised low staff morale, poor professional relationships, safety issues, concerns over mixing mentally-ill patients with frail elderly ones, and the need for single sex wards.
It said: "Relationships between some responsible clinicians and some nursing staff was very poor with staff not talking to each other.
"In addition, some nursing staff were not talking to other nursing staff. The lack of communication and behaviour amongst professionals is unacceptable and must be resolved."
It also pointed out that there was "a lack of training in some key areas across all wards, specifically fire safety and basic life support".
Another criticism concerned a lack of privacy and dignity for patients.
"There are multi-occupancy rooms and the bathrooms are shared between the patients on that ward. There were limited designated male and female facilities," the report said.
"An urgent review of the environment is required."
In response, BCUHB has proposed temporarily reducing the number of beds.
It said the change would "support improved nurse-to-patient ratios, facilitate more appropriate separation of males and females, and also provide for separation of frail older mental health patients and adult mental health patients".
But doctors at the Hergest Unit said the changes would make patients less safe.
They also say it could mean patients being transferred to the mental health unit at Glan Clwyd hospital in Bodelwyddan, Denbighshire, which is currently under police investigation after one ward there was closed last month.
The doctors suggested an extra ward could be opened at the Hergest Unit to deal with the problems instead.
The changes are being discussed at a meeting on Thursday at 10:00 GMT at Wrexham's Maelor hospital.