1. Media Velocity Panel vs Extended Surface
NAFA Technical Seminar
May 2004

2. HVAC Filter Styles Panel Filters Up to MERV 8 performance
Throwaway
Pad
Polyester, Fiberglass
Ring Panel
Sleeve, Link
Autoroll
Up to MERV 8 performance
Typically ½”, 1”, and 2” Depth

3. HVAC Filter Styles Extended Surface Filters
Poly Cube
Pleat
Pocket
Rigid
Aluminum Separator
Cell, HEPA
Minipleat
Panel, V-Bank
MERV 6 and better performance
Typically 1”, 2”, 4”, 6”, and 12” Depth

4. HVAC Filter Styles Extended Surface Filters Carbon Honeycomb Panel
Carbon V-Bank
Carbon Housing
Pleated Carbon Nonwoven

5. Non HVAC Filter Styles Extended Surface Filters Cleanroom Panel
Dust and Liquid Bag
Pleated Bag
Cartridge

6. Sample Calculation Ring Panel Duct Velocity Duct Area Air Flow
500 feet per minute
Duct Area
2’ x 2’ = 4 sq feet
Air Flow
500 * 4 = 2000 cfm
Media Area
Media Velocity
2000 cfm / 4 sq feet
= 500 feet per minute
= Duct Velocity

7. Sample Calculation Pleated Filter Duct Velocity Duct Area Air Flow
500 feet per minute
Duct Area
2’ x 2’ = 4 sq feet
Air Flow
500 * 4 = 2000 cfm
Media Area
2’ x 2’ x ?” = ?? sq feet
Media Velocity
2000 cfm / ?? sq feet
= ???

8. Pleated Filters Contractor Pleat Standard Capacity High Capacity
1” Nominal
¾” Actual
1.00 pleat per inch
1.33 pleats per inch
2” Nominal
1 ¾” Actual
0.80 pleats per inch
1.25 pleats per inch
4” Nominal
3 5/8” Actual
0.75 pleats per inch

9. Pleated Filters Contractor Pleat Standard Capacity High Capacity
1” Nominal
¾” Actual
1.00 pleat per inch
1.33 pleats per inch
2” Nominal
1 ¾” Actual
0.80 pleats per inch
1.25 pleats per inch
4” Nominal
3 5/8” Actual
0.75 pleats per inch

10. Pleated Filter
24” Wide * 0.80 ppi = 19 Pleats

11. Pleated Filter 24” Wide * 0.80 ppi = 19 pleats
24” Tall * 70.7” Wide
= 1,697 sq inches / 144 sq in / sf
= 11.8 sq feet of media
1 ¼”
0.625”
1 ¾”
1.86”

12. Pleated Filters Contractor Pleat Standard Capacity High Capacity
1” Nominal
¾” Actual
1.00 pleat per inch
1.33 pleats per inch
2” Nominal
1 ¾” Actual
0.80 pleats per inch
11.8 sq feet
1.25 pleats per inch
4” Nominal
3 5/8” Actual
0.75 pleats per inch

13. Pleated Filters Contractor Pleat Standard Capacity High Capacity
1” Nominal
¾” Actual
1.00 pleat per inch
1.33 pleats per inch
2” Nominal
1 ¾” Actual
0.80 pleats per inch
11.8 sq feet
1.25 pleats per inch
4” Nominal
3 5/8” Actual
0.75 pleats per inch

14. Sample Calculation Pleated Filter Duct Velocity Duct Area Air Flow
500 feet per minute
Duct Area
2’ x 2’ = 4 sq feet
Air Flow
500 * 4 = 2000 cu ft / min
Media Area
2’ x 2’ x 2” = 11.8 sq feet
Media Velocity
2000 cfm / 11.8 sq feet
= 169 feet per minute

15. Unaccounted Losses Actual Dimensions Blinding Turbulent Flow
23 3/8” x 23 3/8” = 3.8 sq ft = 5% loss
Blinding
Welded Wire – xx%
Paper Die Cut – xx%
Turbulent Flow
11.8 sq feet becomes 11.5 sq feet
169 feet per minute becomes

16. Pocket Filters 24” x 24” x 22” 5 Pocket 24” x 24” x 12” 10 Pocket
Each Pocket
24 H * 22 D * 2
= 528 sq in = 3.7 sq ft
Whole Filter
3.7 sq ft * 5 = 18.5 sq ft
Media Velocity
2000 cfm / 18.5 sf = 108 fpm
24” x 24” x 12”
10 Pocket
Each Pocket
24 H * 12 D * 2
= 288 sq in = 2 sq ft
Whole Filter
2 sq ft * 10 = 20 sq ft
Media Velocity
2000 cfm / 20 sf = 100 fpm