Still not evident to me why you would want or need a vacuum. You
take air out, it will be pulled in wherever there is an opening."
Directionality is a consideration, but only after a vacumm.
Not having a vacumm will not give true air exchange. Similar to
blending eggs, but not rotating the blender- you will have one or two
really blended eggs, but the rest of the bowl will be runny. Your
fumes may be removed from the immediate area, but no larger then
directly under the exhaust. Yes- the intake, if at the other side of
the room, will transfer air toward your exhaust, but this could be
considered a mock exchange. True air exchange happens in areas that
dont have any physical air push/pull because they are in a vacumm.
Imagine trying to remove the air bubbles from a flask of investment
by simply “sucking” them out with a hose. The flask must be in a
vacumm because it creates “Uniform Pull” (and there is a large
difference in density; air to investment). There is no greater pull
in any given spot, therefore allowing all areas to be air bubble free
When your room has a slight vacumm there is no favoritism from where
the air is drawn; it is more universal (and in a PERFECTLY sealed
room it approaches closer to perfect universal pull). This way, the
student in the back will recieve clean air equally (actually just
similar-) to the students sitting close to the exhaust. If you ever
visit a studio that has the vacumm sealed room, you can physically
feel the vacumm (kinda like the feeling of airplane compression) and
how the air exchanges. You can also smoke the room and see how the
air flows. It really is a big difference. Your local
lumber/furniture factory will most likely have one of these rooms due
to thier large work areas and toxic finishing fumes. Thier finishing
areas would never be workable is they didnt create a vacummir
IM not sure how well I explained this, but feel free to hit me up
with clarification. Furthermore, your local OSHA compliant exhaust
expert should be able to give some great advice and clarification.
Nope. Im not an engineer, except when Im trying to resurrect
grandma’s old ring!