How to Determine How Many Negative Air Machines for a Certain Size Room or Building.

"CFM"
CFM (Cubic Feet per Minute) a measurement of air flow.

1.  Figure out the total square footage of the home, times the height of the ceiling to get the total cubic footage of the home or building. ( L * W * H )
     Example: A 2,500 sq. ft home with a 10 foot      ceiling
     will have a total cubic foot measurement of
     25,000 cubic feet.

2. Take the total cubic foot measurement of the home and divide it by the c.f.m. ability of the Neg-Air machine.
     Example: 25,000 cubic home divided by a
     2,000 c.f.m.  Neg-Air = 12.5.   It will take 1 (one)
     2,000 c.f.m.  Neg-Air machine 12.5 minutes to
     change the air in the area 1 time.

* It is the Industry Standard to change the air in a   room 6 times per hour !

3. Divide 60 minutes (1 hour) by the 12.5 minutes it      takes to change the air in a room 1 time.
     Example: 60/12.5 = 4.8. This is the number
     of times this 2000 c.f.m. Neg-Air machine will
     change the air in this size building in one hour.
   
     In this case more c.f.m. will be needed to meet      the standard of 6 times per hour.