In the annual report to Parliament, Custodial Inspector Richard Connock, said after three years' operation it was "even more apparent" that current staffing for the office was "inadequate".

Mr Connock, who holds several statutory appointments including Ombudsman and and Health Complaints Commissioner and is also primarily responsible for Right to Information external reviews, said he could only dedicate 10 per cent of his time to the inspectorate.

He also said the new Northern Prison and Southern Remand Centre would increase the number of custodial centres to be inspected "by a third, from six to eight".

"The inspectorate's budget submission for the 2019-20 financial year requested an increased budget allocation which, at the time, was thought to be adequate: regrettably, the request was not successful," Mr Connock said.

"A request for additional funding is being prepared which will outline what the Inspectorate considers is required in terms of an adequate, functional budget to allow it to fulfil its ongoing responsibilities.

"It is almost certain that with two additional custodial centres to inspect, and without additional resourcing in terms of both financial resources and staffing, the three year mandatory inspection timeframe will not be met."

In his report, Mr Connock also says that increasing prisoner numbers were presenting a challenge for the Tasmanian Prison Service.

"In the 2018-19 financial year, the biggest challenge for TPS appears to have shifted towards staffing shortages with daily 'holes' in the roster creating pressures for staff, ultimately resulting in an increase in overtime costs and a generally fatigued workforce," he said.

"Of considerable concern and highlighted in the Inspection of Adult Custodial Services, 2018: Custody Inspection Report is the issue of lockdowns at RPC due to staff shortages.

"That is to say, TPS is unable to meet the agreed prisoner to custodial staff ratio and to mitigate safety and security risks (when) the prison is locked down."

Mr Connock also said staff at the Ashley Youth Detention Centre were not "adequately trained in diversity, equity and disability awareness."

"There is no clear information for staff and young people at AYDC promoting equity or diversity," he said.

"There is a risk that a young person's concerns may not be adequately addressed, or taken seriously, if they display difficult or challenging behaviours."