Read This Before Buying a PuroAir 400 — My Research Notes
I'm not usually the type to spend a lot of time researching an air purifier. But after a neighbor mentioned the PuroAir 400 unprompted — and then I saw it come up again in a completely different conversation — I figured it was worth actually looking into before pulling the trigger. This is what I found after a few hours of digging. The Coverage Claim Held Up My main skepticism going in was the 2,000 square foot coverage number. Brands throw big numbers around. But the PuroAir 400's coverage rating is backed by independent testing in an ISO 17025-certified lab — the same certification standard used for medical and industrial testing environments. The claim isn't just that it covers 2,000 sq ft; it's that it can clean that space within an hour. That's a meaningful distinction. The Filter Is Not Standard This is the part that actually surprised me. Most air purifiers on the market use a HEPA 13 filter. The PuroAir 400 uses HEPA 14 — a medical-grade filter that an...