UPDATE: the cause of this morning's plant room fire at Hobart's CSIRO precinct has been traced to a lithium battery.
It's understood a bag containing the cordless drill battery caught fire; a nearby airconditioning duct then spread the smoke throughout the building.
Crews remain on the scene ventilating the smoke.
Firefighters including a hazardous materials team have attended Hobart's CSIRO Marine Laboratory in Battery Point this morning due to a fire in a plant room.
Four crews are working to contain the blaze in the Castray Esplanade precinct.
Alarms tripped around a quarter past 8 this morning.
Incident controller Mark Dobson says crews are doing everything they can to limit the damage.
"There's always the possibility of further spread so we'll do everything we can to limit that. There are a lot of laboratories and associate equipment on that floor and on the lower floor, so firefighters are working to limit the damage," he said.