Pure Air Systems IN MERV
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Minimum Efficiency Reporting Values (MERV)
ASHRAE Standard 52.2
Group Number |
MERV Rating |
E1 Average Particle Size Efficiency (PSE) 0.3 – 1.0 Microns |
E2 Average Particle Size Efficiency (PSE) 1.0 – 3.0 Microns |
E3 Average Particle Size Efficiency (PSE) 3.0 – 10.0 Microns |
Average Arrestance (ASHRAE 52.1) |
Minimum Final Resistance (in. W.G.) |
---|---|---|---|---|---|---|
1 | MERV 1 MERV 2 MERV 3 MERV 4 |
– – – – |
– – – – |
Less than 20% Less than 20% Less than 20% Less than 20% |
Less than 65% 65 – 69.9% 70 – 74.9% 75% or greater |
0.3m 0.3m 0.3m 0.3m |
2 | MERV 5 MERV 6 MERV 7 MERV 8 |
– – – – |
– – – – |
20% – 34.9% 35% – 49.9% 50% – 69.9% 70% – 84.9% |
– – – – |
0.6m 0.6m 0.6m 0.6m |
3 | MERV 9 MERV 10 MERV 11 MERV 12 |
– – – – |
Less than 50% 50% – 64.9% 65% – 79.9% 80% – 89.9% |
85% or greater 85% or greater 85% or greater 90% or greater |
– – – – |
1.0m 1.0m 1.0m 1.0m |
4 | MERV 13 MERV 14 MERV 15 MERV 16 |
Less than 75% 75% – 84.9% 85% – 94.9% 95% or greater |
90% or greater 90% or greater 90% or greater 95% or greater |
90% or greater 90% or greater 90% or greater 95% or greater |
– – – – |
1.4m 1.4m 1.4m 1.4m |
Notes
- ASHRAE Standard 52.2 tests are to be conducted at one of seven (7) air flow rates.
- 118 FPM (.60 m/s)
- 246 FPM (1.25 m/s)
- 295 FPM (1.50 m/s)
- 374 FPM (1.90 m/s)
- 492 FPM (2.50 m/s)
- 630 FPM (3.20 m/s)
- 748 FPM (3.80 m/s)
- The air flow rate at which the filter was tested is included in the MERV rating (MERV-10 @ 2.5m/s)
- Filters with an E3 efficiency of less than 20% (MERV-1 through MERV-4) must also be tested for arrestance per ASHRAE Standard 52.1
- Final resistance must be at least twice the initial resistance at the test air flow rate. Or the values shown in the table above, whichever is greater.