A 'humidicleaner'.(CLAIM CHECK)(Venta-Airwasher)(Product/service evaluation)(Brief article)

The claim. The Venta-Airwasher, a "humidifier & purifier--two in one," claims to trap "even the very finest particles as small as 10 microns" while adding moisture to the air. Here's how it works: Plastic discs are mounted on an axle that constantly rotates, dipping the discs in a waterfilled reservoir. As wet discs emerge from the reservoir, a built-in fan evaporates their water, boosting humidity. Particles in the air are supposed to stick to discs, then wash off as discs pass through the reservoir again. There are four models, for rooms of different sizes.

The check. The air-cleaner claim is kind of a nonstarter: A 10-micron particle is so big that it's unlikely to remain aloft for long. So we tested the LW-14 and LW-44 models as we usually test air cleaners, by measuring their ...