Please bear in mind that a single air exchange does not equate to the complete purification of a room's air. This is because the clean air emitted by the air purifier mixes with the polluted air, and this mixture is subsequently drawn back into the purifier. Consequently, one air exchange means that, on average, the air has been cleaned once, although some portions may have been filtered multiple times while some remains untouched. The test results I recently obtained indicate that only after 8 air changes, airborne microorganisms can be reduced by over 99%, and 12 air exchanges to 99.9%. This process takes longer than most people anticipate. Therefore, it is crucial to utilize air purifiers with high Clean Air Delivery Rate (CADR) and Air Changes per Hour (ACH) to ensure effective air purification. https://bird.makeup/@engineer_wong/1862144777787215931
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