Officers at the complex in Lavadia, near Grafton in the NSW Northern Rivers region previously went on strike at the end of September.

The prison's private operator, British government services contractor Serco, says the strike will have minimal impact on operations.

"Serco respects the right of union members to participate in protected action and we have operational response plans ready to implement to ensure the safety and security of the centre is maintained," a Serco spokesperson said.

Serco is committed to further discussions, they said.

The Public Service Association and Serco's own recruitment material says officers at the centre are paid a base of $26.88 an hour.

The union's assistant general secretary Troy Wright says officers put their safety on the line at work.

"It's not right to ask them to do that for the same pay as they'd make scanning shovels at Bunnings," Mr Wright said.

Serco is struggling to recruit or retain staff due to the conditions and wages on offer, Mr Wright says.

"Some nights there are just four officers on duty. It's a disaster waiting to happen," he said.

"One perverse aspect of the chronic understaffing is that every time Serco don't fill a shift, that's more profit they make."

"We know any pay rise won by prison officers will flow straight through the economy of this region which desperately needs it and I bet Serco's shareholders won't notice one way or the other," Mr Wright said.

The local economy was promised a $560 million boost and 600 jobs when the $700 million, 1700-bed minimum and maximum security centre opened in 2020.

Serco was asked but did not confirm how many prisoners are currently at the facility beyond saying it is adequately staffed for the number of inmates.

AAP understands it is not at or near capacity.

Australian Associated Press