The Corrections Association is disappointed the government has not approved a plan to make pepper spray more accessible for prison guards which it says could help prevent assaults on staff.
Three prisoners at the Otago Prison assaulted three Corrections' staff on Saturday.
The association's president, Alan Whitley, said his members wore stab vests and had waited a long time to get pepper spray closer to their control rooms and onto their response officers.
He said attacks such as the one in Otago were always a problem in prisons, where Corrections officers tried to stop fights between inmates, as well as violence towards staff.
"We're a little disappointed we don't have [pepper spray] yet."
Mr Whitley said the move would require a change to regulations for the Corrections staff. He said that process was taking a long time.
"We thought it was going to be done in October last year, then December, we're now in February and we're still waiting."
He said a request was made last year to change the regulations to allow responding officers to carry pepper spray and for it to be held in guard rooms.
Mr Whitley said it was currently held in a prison's central armoury and there was a process for drawing the pepper spray to use it.
He said the Corrections Department supported staff having that access and were waiting on the government to act on the request.
"It's taking longer that we thought it should have.
"What it means is that the responding staff come in, they've got their vests, but they've got nothing else."
Mr Whitley said quicker access to pepper spray would help to quell situations quicker.
MPs back better access to pepper spray
New Zealand First corrections spokesperson Mahesh Bindra is a former prison officer and agreed prison guards needed better access to pepper-spray.
The MP said he had suffered several assaults during his career.
"I think it should be and so does the union - but the (Correction) Department takes the view that it could be misused or used inappropriately, but then there is training for that," Mr Bindra said.
"If it is there, it should be available for use."
Labour's corrections spokesperson Kelvin Davis said it looked like red tape was getting in the way of prison staff safety.
"Workers' safety should be paramount for any employer and if they've got the tools available and they don't have access to them, well that's really silly and it needs to be changed," Mr Davis said.
"If it means having them in secure officers that are more handy - why wouldn't they do it? It's just a bit of bureaucracy gone mad."
In a statement, Corrections Minister Louise Upston said she was taking range of proposed regulation changes, including to pepper-spray rules, to Cabinet shortly.
She said Corrections staff worked in a challenging environment and it was a priority to keep them safe.