Size a Room

Size a Room for an Air Cleaner

Determining the size of your room is as simple as measuring how wide and long it is (Room Width x Room Length = Total Square Feet). To determine your Room Volume, simply multiply the Total Square Feet by the Room Height (Total Square Feet x Room Height = Room Volume).
 
To choose which air cleaner you need you must look at the Room Volume and compare it with the Air Cleaner Flow Rate. The Air Cleaner Flow Rate will help you acheive your desired level of air quality based on the Air Changes Per Hour (ACH). Indoor air quality professionals and Allergists recommend 3 - 6 ACH for each room.
 
To determine how much air must be moved through the air cleaner to provide 3 ACH, you take the Room Volume and multiply by 3 (Room Volume x 3 = Total Volume of Air). Air cleaners provide air flow performance in cubic feet per minute, so you must take your Total Volume of Air to achieve 3 ACH and divide by 60 minutes to get a value for cubic feet per minute (cfm) (Total Volume of Air / 60 = Air Cleaner Flow Rate (in cfm)).
 
 Use the chart below to determine the Air Cleaner Flow Rate you need.
 
Room Size
(square feet)
Air Cleaner Flow Rate
to Achieve 3 ACH
Air Cleaner Flow Rate
to Achieve 6 ACH
75 sq. ft. 30 cfm 60 cfm
100 sq. ft. 40 cfm 80 cfm
125 sq. ft. 50 cfm 100 cfm
150 sq. ft. 60 cfm 120 cfm
175 sq. ft. 70 cfm 140 cfm
200 sq. ft. 80 cfm 160 cfm
225 sq. ft. 90 cfm 180 cfm
250 sq. ft. 100 cfm 200 cfm
275 sq. ft. 110 cfm 220 cfm
300 sq. ft. 120 cfm 240 cfm
325 sq. ft. 130 cfm 260 cfm
350 sq. ft. 140 cfm 280 cfm
375 sq. ft. 150 cfm 300 cfm
400 sq. ft. 160 cfm 320 cfm
425 sq. ft. 170 cfm 340 cfm
450 sq. ft. 180 cfm 360 cfm
475 sq. ft. 190 cfm 380 cfm
500 sq. ft. 200 cfm 400 cfm
525 sq. ft. 210 cfm 420 cfm
550 sq. ft. 220 cfm 440 cfm
575 sq. ft. 230 cfm 460 cfm
600 sq. ft. 240 cfm 480 cfm
625 sq. ft. 250 cfm 500 cfm