Every purifier moves a measurable amount of clean air per hour. Your room needs a measurable amount. Match the two numbers and ignore the plasma-ion marketing modes. That is the whole trick.
4.8 air changes per hour · allergy grade
Find the smoke-CADR number your room needs, then buy any honest machine that clears it.
Delivers 4.8 air changes per hour in your room. On the box this is often printed in CFM: look for 141 CFM or higher.
Clears an average bedroom on its silent setting, because the purifier you turn off at night is filtering nothing.
A plain box with a big fan and a real HEPA filter. No app required, no ionizer theater, just airflow per dollar.
Two mid-size machines at opposite ends beat one monster: better circulation, quieter total, redundancy included.
Smoke CADR is the one third-party-tested number on the box. Ionizer and plasma modes are not, and we treat them as decoration.
A cheap purifier with $90-a-year filters is not cheap. Every pick lists the five-year cost, machine plus filters.
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