The mechanics of High-Efficiency Particulate Air.
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True HEPA filters are certified to capture 99.97% of particles that are 0.3 microns in diameter. This makes them highly effective at removing pollen, pet dander, mold spores, and dust mite feces from indoor air environments.
| Filter Type | Effectiveness |
|---|---|
| True HEPA | Catches 99.97% of particles down to 0.3 microns |
| HEPA-type | Not certified; captures larger particles only |
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Clinical Allergy & Immunology Content
Content is written by our editorial team following current clinical guidelines from ACAAI, AAAAI, and WAO. Educational only — always consult a qualified healthcare provider for medical advice. View editorial policy →
Sampson HA, et al. "Second symposium on the definition and management of anaphylaxis: Summary report" — Journal of Allergy and Clinical Immunology.
View sourceAmerican College of Allergy, Asthma & Immunology (ACAAI) "Allergy Facts and Figures" — ACAAI Clinical Resources.
View sourceWorld Allergy Organization (WAO) "White Book on Allergy — 2025 Update" — World Allergy Organization.
View sourceNational Institute of Allergy and Infectious Diseases (NIAID) "Clinical Guidelines for the Diagnosis and Management of Food Allergy" — National Institutes of Health.
View sourceMuraro A, et al. "EAACI food allergy and anaphylaxis guidelines: Diagnosis and management of food allergy" — Allergy — European Journal of Allergy and Clinical Immunology.
This content reflects clinical guidelines current as of the last review date shown above. Always consult a qualified healthcare provider for personalized medical advice.