Four fire engines were called to an industrial building at 10:20am on Friday morning at Kirk Sandall Industrial Estate on Sandall Lane, Doncaster.
When crews arrived at the scene everyone had been safely evacuated from the building. The fire involved a filtration system and was well alight.
Firefighters wearing breathing apparatus worked hard to tackle the fire.
The fire is now undercontrol and the crews are damping down at the scene (1:45pm).