Atem X
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Search high CADR purifiers. My recommendation is if you are ok spending the money on an iqair unit, to look at other options since you have multiple rooms. What I see right now is the levoit EverestAir on clearance for $299 from Bestbuy. It is an excellent choice with a high 350 CFM CADR. (I just got 2 more at this price) a “comparable” unit is the levoit core 600s-p(sale price 299 410cfm CADR) if the Everest is not on clearance. I would buy the core at the sale price. Owning both the Everest is better in my opinion. As others have stated multiple units will provide more benefit than one large unit. However again if you are spending that money and like iqair please consider the Atem-X as it has a very high CADR. Another option is the SmartAir blast MKII. This is a beast of a unit that targets commercial applications but is generally at the same price point as the larger IQAir units but proving a much higher CADR. I have one sitting in my 600sqft Great room.
I have the Atem X. 1-8 speeds. 1-2 are silent, 3 is quiet, 4 barely noticeable, 5-6 a moderate fan noise, 7-8 a strong whooshing sound, but nothing a pair of ANC headphones or earplugs doesn't quiet. I usually have it between 2 and 4 and it does a great job.
IQAir is the best, but a much higher price category.
Have two different iQair purifiers (on different floors of our house). Have lasted forever and do a phenomenal job. Highly recommend. https://www.iqair.com/
I have heard good things from the Smart Blast, and on paper the performance is impressive. If you want to stick with IQ Air, the IQ Air Atem X is a tried and true beast if you are looking for filtration without carbon. My unit has a certified measured particle removal rate of 706 m3/h or 415.5 CFM and comes with a built-in indoor AQI monitor. I'm very happy with my unit.
Are you looking to move one purifier between your bedroom and living room? I would *not* recommend Airpura or AllerAir unless you have a serious gas/vapor/odor/VOCs issue that can't be mitigated with source control or ventilation. In that case, you'd choose one of their heavyweight carbon purifiers. Airpura and AllerAir do make more particulates-focused units, but they don't list particulate Clean Air Delivery Rates (CADRs). They're also known for be very loud. Both are Canadian companies that manufacture largely in Canada and some components in the USA. Levoit is lower quality than IQAir and Coway. The [IQAir Atem X](https://www.iqair.com/us/products/air-purifiers/atem-x) you linked in a comment is high quality and has CADRs in the 400s CFM, but it's very expensive per CADR. As for "True" HEPA, I would say that listing the standard and filtration efficiency at Most Penetrating Particle Size (MPPS) gives you the best idea of performance. There are several HEPA standards. But I don't think there's a significant difference between brands on this front; they will still clean your air. The [Coway Airmega AP-1512HH Mighty](https://cowaymega.com/products/mighty-ap-1512hh) you linked is commonly recommended. It's a good price point and attainable for many. But the Mighty has a few drawbacks like being less energy efficient, somewhat loud, and occasionally people have reported balance issues (e.g., purifier "walking" across a floor). The [Coway Airmega 400](https://cowaymega.com/products/airmega-400) was probably recommended in part because it's "oversized" for your bedroom. Oversizing allows you to run the unit on a quieter setting while hopefully maintaining CADRs. ➡️ If you're expecting one purifier to clean both the living room and bedroom areas, I would also recommend the Coway Airmega 400. The highly upgraded pick would be the [Coway Airmega ProX](https://cowaymega.com/products/airmega-prox). Top Smoke CADR is 568 CFM. It has wheels so you can move it around easily and it shows PM10, PM2.5, and PM1.0 concentrations. Obviously the ProX is fairly big. Keep in mind that CADRs apply to the highest airflow speed/setting *only*. Lower settings have lower CADRs, which reduces cleaning effectiveness. Right now there aren't any fantastic sales directly from Coway. But you can use the discount codes **COWAYMEGA10** or **FORYOU10** for 10% off most items.
I would avoid the Dyson Big+Quiet models. I don't think the particulate air cleaning nor the build quality matches the price tag. Per **Rule 4: Information For Air Purifier Requests** and repeated in the AutoModerator comment, purifiers are sized by room volume. Let's assume your ceilings are 2.4 meters high. 50 m^(2) × 2.4 m = 120 m^(3). For rooms measured in meters, minimum Clean Air Delivery Rate (CADR) should be 3 times the volume (in m^(3)). 120 m^(3) × 3 = 360 m^(3)/h CADR. If you have allergies or high pollution levels, you'll want to multiply the room's volume by 4-6. Using the 120 m^(3) value, CADRs should be 480 - 720 m^(3)/h. If you have no budget, I'd go for the [IQAir Atem X](https://www.iqair.com/products/atem-series/atem-x?Style=EU+Plug+Type+C). It's made in Germany. Per the AHAM AC-1-2020 standard, top Smoke CADR is 422 CFM or 716.983 m^(3)/h. The CADR I've listed for the Atem X applies to the highest airflow speed/setting only. Lower settings will have lower CADRs which reduces cleaning effectiveness.
IQair.com. …our mold test numbers have gone way down since getting it. The air SMELLS different.
The big IQ air they have in hospitals. Cost a fortune but you can't beat it
I can clearly tell when my IQAIRs are running, I sleep so much better. You might already have good air quality Fixing your furnace filter and central filtration will make a bigger difference than buying an air purifier
I run 3 filters, Austin and IQAIR, in each of 2 spaces - one 300 square feet the other 600 square feet. If the air is poor outside my Purple Air sensors will still show green. However there are so many chemicals in wildfire smoke, particularly if structures have burned, that they don't get everything. I am sensitive to terpenes and right now they don't help with the Camphor tree flowers. So they can greatly improve air quality but don't expect all VOCs to be removed from the air.
For best VOC removal, such as mycotoxins, you need a lot of absorbent media. Checkout Airpura, Allerair, Austin, IQAir. All are in the $1k range. I'm unsure whether any filter will eliminate mold sensitivities. Did see an improvement when upgraded my Austins with Immunity Machine filters but molds still aren't totally controlled. There are clinics which can treat mycotoxin sensitivities. Can be quite expensive.
Running both IQAir and Austin Immunity Machines in my major rooms particulates run from 0 to under 10.
I have had my Austin, IQAir, Honeywell and Whirlpool machines for as much as \~20 years and have had no problems with filter replacements.
The 4 vendors with the best VOC filters are Airpura, Allerair, Austin, IQAir. Absorbent media composition and weight vary by manufacturer. IQAir has models that go up to 32 pounds of media, at least according to google search. Note that no VOC filter will remove all VOCs. They do well with some chemicals, partially control some, and totally ignore others. I use IQAirs and Austin Immunity Machines, multiple units per room unless you want to put up with the noise running the fans on high speed. Had a room repainted and requested a low VOC paint. Was pleasantly surprised that I had no problems with the paint even though I am extremely chemically sensitive. It is possible that the renovations don't cause a VOC problem at all, or maybe just for a few days.
My Austin, IQAir, Honeywell and Whirlpool filters all work with smart plugs. When you purchase make sure you can return if it doesn't work as features change over time.
Alen is excellent. So is IQair