Union delegate Tanya Oomen said often workers were put in the position where they were "physically and verbally abused" by those they are caring for.
"It is not every worker, every day, but it is a risk," she said.
A media statement from the union said staff were fed up with feeling overworked and undervalued, with understaffing leaving them working long hours and needing more pay to compensate for time away from family.
IDEA Services chief operating officer, Joan Cowan, said although there would be some disruption to some services, IDEA had ensured people with intellectual disabilities would be safe during strike action.
"Each area has a plan in place, and anyone who has concerns or questions is encouraged to contact their local area office."
She said IDEA Services remained committed to trying to achieve a collective agreement from negotiations with the union representing staff and was listening to them.
"We have been carefully considering all demands, either financial or otherwise, and are continually balancing staff remuneration with other quality improvement priorities."