Firefighters are working to extinguish a blaze in a derelict outbuilding near the a Waterfall nursing home.
About 3pm, firefighters were called to the Garrawarra Centre after reports black smoke was coming from the nursing home.
Firefighters found a small outbuilding well alight on the grounds near the centre.
No one was inside the building.
NSW Fire and Rescue Superintendent Mick Henley said eight Fire and Rescue officers and four Rural Fire Service officers are working to extinguish the blaze.
"They are using four big hoses," he said. "Asbestos has been identified.
"A HAZMAT team and senior inspector are on route.
"The fire has been contained, it is not spreading and there are adequate resources trying to extinguish the fire."