The findings are part of the report published on Friday which said the prison's overall performance was poor.

The inspection in March also found that inmates' cell alarms were frequently muted by staff. But relations between staff and inmates was praised.

The prison's governor James Shanley said many of the 179 recommendations made had now been implemented.

HM Chief Inspector of Prisons Anne Owers said: "Key functions within the prison were inadequate and had been poorly managed.

I'm proud of my staff, they do a good job in difficult circumstances with some of the most complex people in society Governor James Shanley

"A performance improvement programme, under a new governor, is trying to deal with some of these weaknesses."

The report also said healthcare accommodation at Norwich Prison was among the "worst" it had seen, and the use of unscreened toilets in some cells was criticised.

Mr Shanley said: "Over the years there has been a lack of investment in prisons and it (Norwich Prison) is a Victorian prison.

"But within the healthcare centre we have now secured �50,000 for a refurbishment and that work will start in November.

"The body of the report continually talks about the good staff and prisoner relationship.

"If you walk around the prison you can see the good atmosphere, and the relationship between staff and prisoners is extraordinary.

"I'm proud of my staff, they do a good job in difficult circumstances with some of the most complex people in society."