MERV Ratings Explained: The Complete Chart
MERV (Minimum Efficiency Reporting Value) rates an air filter's ability to capture particles, from MERV 1 (basic) to MERV 16 (very high efficiency). Higher MERV captures smaller particles. Homes generally use MERV 8–13, commercial buildings MERV 13–14, and critical environments MERV 14–16 or HEPA.
Full MERV rating chart
| MERV | Smallest particles captured | Examples | Typical use |
|---|---|---|---|
| 1–4 | > 10 microns | Pollen, dust mites, carpet fibres | Basic equipment protection |
| 5–8 | 3–10 microns | Mold spores, hairspray, cement dust | Homes, light commercial |
| 9–12 | 1–3 microns | Pet dander, fine dust, auto emissions | Better homes, commercial |
| 13–16 | 0.3–1 micron | Smoke, bacteria, respiratory aerosols | Hospitals, offices, smoke control |
How MERV is measured
MERV is determined by ASHRAE Standard 52.2, which measures how efficiently a filter captures particles across twelve size ranges from 0.3 to 10 microns. The MERV number reflects the filter's worst-case performance across those ranges, so a higher MERV guarantees minimum efficiency on the smallest, hardest-to-catch particles.
Frequently Asked Questions
What does MERV stand for?
MERV stands for Minimum Efficiency Reporting Value, a standardized scale (1–16) from ASHRAE that rates how well an air filter captures airborne particles.
Is a higher MERV always better?
Not always. Higher MERV captures more particles but adds airflow resistance. The best choice is the highest MERV your system can handle without restricting airflow — usually MERV 8–13 for homes and 13–14 for commercial buildings.
What is MERV 13 good for?
MERV 13 captures smoke, bacteria, and respiratory aerosols in addition to dust, pollen, and dander. It is the recommended baseline for allergies, asthma, wildfire smoke, and occupied commercial spaces.
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