Services at Orange and Bloomfield hospitals will be "dramatically" slowed due to industrial action planned for August 1, the Health Services Union has claimed.
HSU secretary Gerard Hayes said the union's 450 members in Orange would be going on strike for four hours to highlight concerns about security.
Mr Hayes said about 22,000 workers across NSW would be involved.
"This will slow things down dramatically," he said.
However, Mr Hayes said patients would not be put at risk by the strike.
"Patient safety is paramount. We will not endanger patient security," he said.
He said the union covered all hospital workers and paramedics "except for doctors and nurses."
This will slow things down dramaticallyGerard Hayes, Health Services Union secretary
Mr Hayes said staff and the union were fed up with stabbings and attacks on staff at public hospitals.
"It is a little bit more significant for Orange with [the stabbing death of a nurse at Bloomfield hospital in 2011]," he said.
"That is the level of violence that is becoming more and more commonplace across NSW hospitals," he said.
Mr Hayes said the August 1 strike was just the start of the union's planned action.
"This won't be the end of it," he said.
"We've seen too many people stabbed, too many people shot, too many people who have been spat upon or punched."
He described the situation as "dire" and said when it came to violence staff at the Orange Health Service had the same experience as staff at other NSW hospitals.
He said rolling stoppages would start on August 1, and would escalate until the matter was resolved.
He said it was appalling that since a statewide review in 2016, nothing has been done to address it.
"It's been three years, and nothing has changed," he said.
Mr Hayes said he would be meeting with NSW health department officials on Friday about the planned action.
A NSW Health spokeswoman said the department would seek the assistance of the NSW Industrial Relations Commission to resolve any planned industrial action.
She said there has been an increase in security staff from 974 full-time equivalent staff in 2010 to 1243 in 2018 across NSW.
The NSW Nurses and Midwives' Association said nurses and midwives offered their in-principle support to the HSU members who voted to take industrial action.
"However, rostered nurses and midwives will remain at the bedside in hospitals and other health settings across the state," a statement from the NSWNMA said on Tuesday.
"Current violence prevention measures are clearly inadequate and require urgent attention," it said.
DO YOU WANT MORE ORANGE NEWS?
- Receive our free newsletters delivered to your inbox, as well as breaking news alerts. Sign up below ...