BreathHarbor
Figure 1 · a living room, honestly annotated

You can see dust in a sunbeam. Here is the whole system it belongs to.

One drawing explains every purifier decision: where particles enter, why room volume is the number that matters, and what a purifier can and cannot reach. Toggle the room state, then size yours on the control panel.

At the window

Particles are a flow, not an event

Pollen, traffic soot and cooking smoke re-enter constantly. Clean air is a rate you maintain, never a level you reach once.

The whole room

Volume is the real customer

The purifier serves every cubic meter, not the corner it sits in. That is why the calculator below starts from your room, not from a product.

At the machine

CADR is the only number on the box that was tested

Smoke CADR is third-party measured airflow of clean air. Ionizer and plasma modes are not, and this drawing treats them as decoration.

Control panel · room-to-CADRmatch, then buy anything honest
240 m³/h CADR

Delivers 4.0 air changes per hour. Boxes often print CFM: look for 141 CFM or higher.

Legend: how the picks are drawn

Bedrooms run on night mode
A purifier you switch off at night filters nothing. Quiet-setting CADR is the spec that matters for sleep; around 19 dB clears a bedroom.
Filters are the real price
Every pick lists the five-year cost, machine plus filters. A cheap unit with $90-a-year filters is not cheap.
Two beat one in open plans
Two mid-size machines at opposite ends beat one monster on circulation, noise, and redundancy, and usually on price.
Affiliate-funded
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