Fifty-five of the 130 correctional workers at a multi-level psychiatric hospital in Saskatoon operated by the Correctional Service of Canada are on workers' compensation because of attacks by inmates, CBC has learned.

Thirty-two are on full leave, with the balance working "accommodated" hours, according to an officer CBC spoke with and the union representing correctional workers at the Regional Psychiatric Centre.

The staffing shortfall is being addressed through overtime with the remaining workers, the officer said.

Staff members say this year has seen a troubling spike in assaults at the prison hospital. They blame a change in policy earlier in 2017.

As an example, they cited an incident just before midnight Oct. 31, when a group of 14 inmates dressed in black refused to go to their cells.

"Inmates planned to take over the Bow [unit] computer panel and use force against the four correctional officers on that 'open area' post," said an officer at the centre, who spoke on the condition of anonymity. CBC News has agreed not to name the officer.

"These officers would have been very badly beaten. Very lucky that [the inmates] were talked down, just to lock up for the evening."

The union that represents Corrections Canada workers says that changes made by Correctional Service of Canada earlier this year to the policy around administrative segregation — the practice of separating inmates from the general population — triggered a rise in assaults.

"There's just been continuous assaults of throwing urine and feces on officers, spitting on officers, biting — we've had officers been stabbed with pens. We've had a lot of physical assaults in that way. It's just been continuous," said James Bloomfield with the Union of Canadian Correctional Officers.

"The inmates that are assaulting us are right in front of us the next day. There's no repercussions for them."

Correctional Service of Canada changed its segregation policy in August.

According to CSC's website, the new policy does not allow staff to segregate inmates "with a serious mental illness with significant impairment" or inmates "engaging in self-injury which is deemed to likely result in serious bodily harm."

Blood running from a cell at the Regional Psychiatric Centre is not an uncommon sight, staff members say. (Submitted) Bloomfield said this change applies to nearly all inmates at the psychiatric hospital.

"The change in the segregation area means that you cannot segregate a mental health inmate," he said.

"When we look at a place like the Regional Psychiatric Centre, you can imagine how we can't segregate anybody. We can't take them out of the general population."

Corrections Canada would not discuss the specifics of what's happening at the Saskatoon centre.

In an email to CBC, spokesperson Kelly Dae Dash confirmed there have been assaults on inmates and staff, but would not provide further details about numbers of staff off work or the types of assaults.

"What I can say is we do not tolerate violence in our institutions. Disciplinary action is taken and criminal charges can be laid against offenders involved in violent incidents," she wrote.

"CSC examines each incident of violence to find out how it can better prevent and address these situations."