Each of ten factors gets up to 10 points, 100 is perfect and very unlikely.

1. First do no harm; minimal out gassing, no ozone.

Score: 10 of 10.

2. Serious airborne gas and odor removal is a requirement if health benefits are expected: aircleaners with real carbon VOC capability rank higher.

Score: 9 of 10.

3. Quality construction; case, gaskets, seals, and precision fitting eliminate bypassing and assure high efficiency at filtering sub-micron particles.

Score: 10 of 10 one airtight aircleaner.

4. The aircleaning design maximizes the lifespan of each filter stage by allowing independent filter replacement. Ideally this is combined with electronic filter monitoring.

Score: 10 of 10.

5. Cleaner has long filter life, low maintenance requirements, and reasonable operating costs.

Score: 8 of 10, a retailer reports gas filter cartrige replacement more frequent than specs.

6. Purifier produces low noise levels and meaningful airflow rates relative to noise.

Score: 8 of 10, a bit loud on high.

7. Manufacturer has a track record, with many units in the field and a reputation for supporting what they sell. Warranty period and average service life are long.

Score: 10 of 10, In my view, 5-year warranty could be longer.

8. Purifier is a value in terms of price/performance ratio. Every price range should be included, “models above $1,200 are best”, while true, is not useful to most consumers.

Score: 10 of 10, worth the money.

9. No dirt; clean air machine and manufacturer should be devoid of class-action suits, high returns, recalls, consumer complaints, and legitimate negative consumer reviews.

Score: 10 of 10, so clean they squeak.

10. Unit is stylish, portable, comfortable, and convenient for consumer use.

Score: 9 of 10, a bit boxy for the stairs, handy remote, easy interface.

Iq Air Cleaner Air-Purifier-Power Numeric Rating; 94, fairly tough to beat.