A:Answer Moisture can damage any electronic device. Fog from a fog machine is moist. The fan on the projector has open vents. This would allow the fog in. I wouldn't recommend using a fog machine near this device, not to mention it could create issues for the lense. Finally, the online manual (yeah, I read that long thing) states that any damage due to moisture/condensation/water exposure voids Any warranty. I would assume that includes additionally purchased warranties as this would be considered negligence.