Air cleaning rates

The performance of air cleaners depends on the:

Airflow rate – the amount of air that they process

Equipment efficiency – how many particles they remove from the air as it passes through

The performance changes over time as the airflow drops as the filters become loaded with particles. The performance of each unit will decline at a different rate.

It is difficult to compare air cleaners as they use different technologies and layouts.

There have been attempts to make a comparison between different units simpler by laboratory testing the effectiveness of equipment in clearing a test chamber of smoke when the units are new and when they have been loaded with the smoke from 500 cigarettes.

One means of evaluating air cleaners is the Clean Air Delivery Rate (CADR) , although this is more commonly used for domestic air cleaners.