Nurses at Christchurch's Hillmorton Hospital are set to get help from security guards.
Around 50 nurses met with district health board officials on Friday after ongoing assaults.
New Zealand Nurses Organisation spokesman John Miller says there were honest and frank discussions.
"Our members have asked for it… they are going to bring in some security guards, directly into the unit."
Three staff members have been injured in recent weeks.
Mr Miller says some are scared to go to work.
"They're most concerned about being assaulted, about the violence," he told Newshub.
He said the "bigger picture" is "developing a different workforce that is trained in de-escalation, working alongside people in the units, being able to - if required - restrain patients and support the nursing team".
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