The most important component of air filters
The most important component of any air purifier is, unquestionably, its air filter or filters. For this reason, the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE) certifies and tests air filters in order to gauge their performance and their effectiveness. Two basic ratings are involved: The Initial Staining Dirt Efficiency, which measures how effective a filter is against tobacco, grease and other things, and the Average Arrestance Test, which measures what percentage of things like hair, lint and dust are processed. Air purifiers that use well-rated filters work the best.