Powermatic PM1200 Air Filtration Question

[chris dub]

I recently purchased an air filtration unit. I got the PM1200. I have a 1 car garage (11x19x8). it may have been a bit of over kill, but I figured since it is for my health, why not.

Now to my question. Since the outer filter can use store bought furnace filters, would a premium filter like the one attached that has the highest Microparticle Performance Rating cut off too much of the air flow as an outer filter. I believe these can filter down to something like .3 microns or so. I was thinking that would be even better than the 1 micron inner filter does. And since they are often sold in bundles the price per filter can be fairly reasonable, with a nice health benefit.

http://www.filtersfast.com/3M-Filtrete-Advanced-Allergen-Air-Filter.asp (http://www.filtersfast.com/3M-Filtrete-Advanced-Allergen-Air-Filter.asp)


Any thoughts would be appreciated.

[Nathan Wittman]

I looked at the information on that unit online. It has a pleated pre-filter (25% efficient on 1 micron) and a 85% (85% on 1 micron) as the 2 stages that come in the system. The pre-filter's only purpose is to protect and extend the life of the final filter. So, by installing a higher efficiency pre-filter, you are not doing any better job of actual filtration, but extending the life of the more expensive final filter.

Think of it as putting 2 fences around your back yard, a chain link and then a brick wall. The first fence is chain link, which would filter out kids and dogs, the second fence would filter out just about everything, but if the chain link fence was not there, then you would not lose an efficiency in filtering out kids and dogs with just the brick wall.

Let me know if you have any additional questions about air filtration, as that is my business. I own an air filtration company and we specialize in industrial/commercial/healthcare.