SOME areas of Tomaree Hospital were evacuated on Sunday as staff detected smoke in the building.
Emergency services were called to the site about 11am to reports of a possible fire.
The smoke was thought to be coming from an air conditioning vent on the premises. Some areas of the hospital were evacuated as a precaution while NSW Fire and Rescue crews investigated the source of the smoke.
No fire was found and the area was deemed safe.
Hunter New England Health shut the hospital to everyone except those needing emergency care while the incident was under investigation.
"There is currently a disruption to normal services at Tomaree Hospital, with smoke detected inside the facility," a statement released on Sunday said.
"All patients and staff are safe and will continue to receive care as required.
"The hospital is still operational and patients requiring emergency care can still present to the hospital, however ambulances have been temporarily diverted to other facilities as a precaution. Please avoid the area unless you require urgent medical assistance."
