Glossary · Health & indoor air
HEPA filter
Also called: HEPA · true HEPA · high-efficiency particulate air filter · HEPA vacuum
A very fine high-efficiency particulate air filter used in portable air cleaners and vacuums to trap smoke, dust and other small particles.
What it means
Portable air cleaners often reach a high clean air delivery rate (CADR) by using a HEPA filter, and some studies have found small health improvements from using them. A HEPA vacuum traps fine dust instead of blowing it back into the room.
Why it matters in an audit
During wildfire smoke or renovation dust, a correctly sized HEPA air cleaner is one of the quickest ways to lower fine particles indoors.
Typical numbers
Reference values with their sources. Your auditor’s report gives the figure for your own house.
| What | Value | Source |
|---|---|---|
| Sizing a portable air cleaner (EPA) | Minimum CADR of about 65 cfm for 100 ft², 130 for 200 ft² and 195 for 300 ft² (8-foot ceilings) | epa.gov ↗ |