The Corrections Department is reviewing its complaints process as inmates have made multiple allegations about sexual and serious assaults against Corrections staff.
As it stands the current reporting system does not allow information from initial investigations and following investigations to be collated.
"Between 2012 and 2016, there were 16 allegations of sexual assault and 15 allegations of serious assault made against staff," Corrections chief custodial officer Neil Beales said.
Two of those allegations were made by female inmates.
Corrections could not say how many, if any, guards were stood down, a spokeswoman said.