Re: Shop Air Changes

Posted by ndeanmoseyjr on Dec 18, 2006

Computing the rate of air exchange (make-up air) and size fan needed can get a bit tricky as there are many factors involved. In my commercial shop, the simple rule at the base level is for every cubic foot of air that goes out of the building, a cubic foot of fresh air must come in. I'm in MI so that puts me roughly in the same yak as someone in MN. I have two heating furnaces tied directly to my spray room to keep heat at a constant in the dead of winter. These are in addition to my general heat source. One must also remember that it will suck the air conditioned coolness out equally fast in the summer. It CAN get costly. Remember that fan speed is important and a fan can run too fast....over a certain speed and it will actually remove less air. If you don't have a source of return air, your enclosure will build up an inverse pressure or vacuum effect and even less matter can be eliminated. In all cases it is advisable to use a fan that has a TEFC motor as is rated for hazardous use. It is truly a safety issue.

In Response to: Shop Air Changes by Dan B on Dec 17, 2006