[johntodd]

Hello
I work at a small college where we are thinking of buying a portable fumehood for doing lecture demonstrations in chemistry. 
It's hard to decide if it would be worthwhile (~7000 $CNDN) without having seen one in operation.  Can they handle the smoke of a gummi bear combustion?  The sparks from thermite?  Are they noisy to speak over?  How is the glare/visibility through the plastic?
If anyone on the forum has experience with ductless portable fumehoods for demos, either as lecturer or student, I would appreciate your opinion.
Thank-you
Todd Stuckless