A plain air purifier in a spacious bedroom

Sizing and use

CADR, room size, placement, and portable vs whole-house.

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A plain air purifier in a calm, evenly lit room

CADR, explained

How to read the rating.

One white cylindrical air purifier on a dark smooth floor by a pale, sunlit wall

Air purifier room size, explained

Square feet and ceilings.

A low round air purifier on a grey rug in a dim room with long curtains

Where to put an air purifier

Placement, speed, and noise.

A wall air grille in a hallway and an air purifier beyond

Portable vs whole-house air cleaning

One room, or the whole home.

Start with cadr

How to read the rating.

Read cADR, explained

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