Striking prison officers have been ordered by to return to work by the NSW Industrial Relations Commission (IRC).

Commissioner John Murphy this afternoon ordered members of the Public Service Association and Professional Officers Association to notify their members of the order by 4:00pm.

The union told a hearing of the IRC that it did not instigate the industrial action, rather that it was initiated by officers on a prison-by-prison basis.

The order against industrial action remains in place until May 12.

Earlier, up to 4,000 prison officers across New South Wales had gone on strike to protest proposed job cuts.



Corrective Services NSW said the "unauthorised" industrial action was "unnecessary and inappropriate".

All jails across the state held stop-work meetings and staff at most facilities went out on strike.

A spokesperson for the NSW Chief Magistrate's and Chief Judge's Office said the impact of the strike on courts had been "significant" as custody matters had not been able to proceed today.

The majority of those matters were adjourned to new dates.

"The industrial action has had a major detrimental impact on both trial and sentence matters listed today in the District Court," Chief Judge, Justice Derek Price, said.

General secretary of the Public Service Association Stewart Little said the walkout was in response to the NSW prison system being in "crisis".

Staff at both the Goulburn supermax prison and Long Bay jail in Sydney walked out as each facility faces 90 job cuts.

"We have a prison population that is fast approaching 14,000 ... it's a system that is designed and built for 11,000 inmates," Mr Little said.

"This has come about because of a complete failure by the Government to adequately manage and plan for that system ever since the bail laws were changed back in 2014.

"This seems somewhat incredulous when you think that the prison population is fast reaching record levels [and] we are not meeting any KPIs."

Mr Little said the prospect of job cuts was "crazy and ludicrous".

"There are over 1,700 inmates at Long Bay, in the middle of suburban Sydney, if you can convince me that's a good idea you are doing well.

"[And] Goulburn is the toughest prison in Australia and is full to the brim."

Assault rates have tripled in the last three years and these cuts will put officers' lives at risk, Mr Little said.

Despite the action, there was no concern to safety Mr Little said, as all prisoners were secured in their cells.

However he called on Corrections Minister David Elliott to "come down to Long Bay Prison, spend a day in our members' shoes, and then tell me cutting officers is a safe move".

2,000 new jobs expected over two years: Corrective Services

Chair of Prison Officers Vocational branch Nicole Jess said the Department of Correctional Services had failed to work with staff.

"[Long Bay] have done risk assessments to prove that these job cuts will be unsafe," she said.

But Corrective Services NSW said discussions with relevant parties had been "cooperative" and no decisions on job changes had been made.

Benchmarking is being applied to all prisons across the state which will ensure they are "efficient and taxpayers receive best value for money", a spokesperson for the department said.

"It involves reduced staff in some areas of prison operations and extra staff in others.

"This is based on … careful risk assessment of any proposed changes."

The department will aim to find alternative jobs for any staff whose positions have been affected and said 2,000 new jobs were expected to be created in the next two years.

Mr Little said the department had ignored the union's repeated requests for data on benchmarking due to cabinet confidence.

