How It Works
What is a PM2.5 filter? PM2.5 is an ISO standard referring to tiny airborne particulate matter that are the less than 2.5 microns (0.0025mm) wide – or 3% the size of human hair. A PM2.5 filter is designed to filter airborne particulate matter smaller than 2.5 microns. ISO describes the efficiency of such filters to be capable of filtering particle sizes in the range of 0.3 microns to 2.5 microns.
What are PM2.5 filters made of?The filter consists of five layers of activated carbon filter and different kinds of fabric:
- Layers 1 and 5: Spun-bound non woven material that filters out larger particles
- Layer 3 (middle): activated carbon layer. Traps particulate matter via an adhesion process.
- Layers 2 and 4: high-efficiency melt-blown filtering material that can filter small substances.
How long does the PM2.4 filter last? The PM2.5 filter longevity will depend on, of course, how much it is used and the intensity of particulate matter in the environment it is used. In a highly polluted city, or during forest fire haze, it will probably last 3-4 uses due to the higher concentrations of particulate matter.