What is air flow?
For most home appliance or electronics purchases, we know what specs are important. Is this TV high-def or 4K? What’s the capacity of this refrigerator? How much water does this washing machine use per load? For air purifiers, however, the facts and figures might not be as clear.
At the same time, having high-quality indoor air is important for both short- and long-term health, as well as managing conditions like asthma and allergies. So understanding what’s important in a purifier is just as — if not more — important than making sure that new fridge has adequate crisper drawer storage. Aside from choosing a model with a high-quality filter, a unit’s air flow stats are of vital importance to its performance. Here’s what you need to know:
Okay, you’ve got my attention. What is air flow?
Air flow is the rate at which air runs into a purifier in a given period of time. Generally, flow rate is measured in cubic feet per minute (CFM). The primary factor that determines a purifier’s air flow rate is the strength of its fans, which are responsible for pulling air into the unit and through the filters. The more “dirty” air a purifier can ingest, the better it will be at sending clean air back into the room.
Makes sense, but is air flow a spec I can look for on a box?
Not necessarily. Most commonly, what you’ll see advertised are a purifier’s coverage area (that is, how large of a space its fan, or fans, can reach) and air changes per hour (ACH). Think of ACH as the speed of an air purifier. Take the Airmega 400S as an example: Thanks to its dual fan system (there’s one on either side of the unit), it’s able to cover rooms up to 1,560 square feet, and can cycle through all the air in that space twice in one hour. In a room half the size, it can clean the air every 15 minutes.
Is that good?
In a word: Yes. At minimum, experts suggest purifiers have an ACH of four cycles per hour. Those suffering with serious allergies may need to up the ante to two cycles per hour, or invest doubly in purification to make up the difference.
Disclaimers
1 Airmega air purifiers have been proven to trap dust, pollen, dander in the air based on KCL(Korea Conformity Laboratories) testing. They have been tested according to the Korea Air Cleaning Association standard (SPS-KACA 002-132:2022 Modified) to measure the 0.01㎛ size of particle removal rate. It was tested on maximum airflow speed in normal room temperature and humidity conditions. The performance may vary in the actual living environment of customers. Tested with Airmega Aim, 50, 100, 150, Tower AP-1216L, Mighty AP-1512HH, MightyS AP-1512HHS, 200M, Icon, 230, 240, 250, 250S, 300, 300S, 350, 400, 400S, 450, ProX
2Our HEPA filter complies with IEST-RP-CC007 standards at speed level 1 as tested by SGS (Société Générale de Surveillance). SGS's test report only reflects SGS's evaluation of the sample and does not reflect the evaluation of the batch of goods from which the sample was taken. Tested with Airmega 100, 150, 160, Mighty AP-1512HH, MightyS AP-1512HHS, 200M, 230, 240, 250, 250S, 250 Art, 300, 300S, 350, 400, 400S, 450, ProX
3 Tested by KCL(Korea Conformity Laboratories) according to JEM 1467: 2015 condition, the concentration of acetic acid was proven to be reduced up to 99.5% in 60 minutes. Results may vary depending on actual environment. Tested with Airmega 150, Mighty AP-1512HH, 200M
4 Tested by KCL(Korea Conformity Laboratories) according to SPS-KACA002-132:2022, showed result of over 99.5% removal rate of common household gases including Ammonia, Acetaldehyde, Acetic acid, Formaldehyde, Toluene, Benzene, Nitrogen dioxide (NO₂), and Sulfur dioxide (SO₂) within 30 minutes. Results may vary in different environments and not all odors or gas particles may be removed. Tested with Airmega MightyS AP-1512HHS, 250S, 300S, 400S, 350, 450
5 Test conducted using Coway Allergen filter media (5×5 cm) placed in a polyethylene bag. The allergen solution and sample were immersed in 2 mL of phosphate buffer (100 ng/mL) prior to the reaction and heat-sealed to specimen size. The reaction was maintained at 4°C for 24 hours. Nichinichi Pharmaceutical Co., Ltd. conducted the test using ELISA to measure allergen concentration. Results may vary in actual product usage environments. Tested with Airmega Mighty AP-1512HH, 200M
6 Removal rates of Ammonia (NH₃) and Hydrogen Sulfide (H₂S) were tested in a 1 m³ chamber under EL608:2023 conditions for 30 minutes. Gas Detector Tubes were used for measurement, and testing was conducted by KCL (Korea Conformity Laboratories). Results may vary in actual product usage environments. Tested with Airmega Mighty AP-1512HH, 200M
7 Reduction rates of Naphthalene, Sulfur Dioxide, and Nitrogen Dioxide were tested using the Airmega Mighty AP-1512HH in 1㎥ chamber, following JEM-1467:2015 standards. Tests were conducted by Intertek. Actual performance may vary depending on the living environment. Tested with Airmega Mighty AP-1512HH, 200M
9 Tested by KCL(Korea Conformity Laboratories) according to SPS-KACA002-132:2022. The test was conducted with Methyl mercaptan, Isovaleraldehyde, Isovaleric acid in a 1.0±0.1 m³ chamber with a test time of 60 minutes at (24±4)°C and (46±10)% Relative Humidity. A removal ratio of over 99.5% was achieved. Results may vary depending on the actual usage environment. Tested with Airmega 350, 450
10 Tested by the Guangzhou Institute of Microbiology, exposed the filter media to protein solutions for 24 hours under ISO 4333-2022 standard. The results showed strong reduction performance: >99.79% for pollen, >99.60% for dog allergen, >99.90% for cat allergen, and >99.80% for dust mites matter allergen. Actual results may vary depending on room size, airflow, and pollutant levels. Tested with Airmega 350, 450
11 Tested by KCL(Korea Conformity Laboratories) according to SPS-KACA002-132:2022. The test was conducted in a 1.0±0.1 m³ chamber for 60 minutes at (24±4)°C and (46±10)% Relative Humidity. A removal ratio of >99.5% was achieved for Formaldehyde and Toluene in 60 minutes. Results may vary depending on the actual usage environment. Tested with Airmega 350, 450
12 Tested by Intertek. The evaluation was conducted against designated test materials: Sulfur dioxide, Nitrogen dioxide, and Naphthalene. The test was performed in a sealed 1.0×1.0×1.0 m (1.0 m³) odor chamber at a test room temperature of (23±2)°C (measured between 23.6∼23.9°C) and a test room humidity of (45±5)% R.H. (measured between 40∼48)% Relative Humidity. It met the odor removal rate of ≥99.9% for Sulfur dioxide, Nitrogen dioxide, and Naphthalene. Results may vary depending on the actual usage environment. Tested with Airmega 350, 450
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