8 Best HEPA vs Electrostatic Air Purifiers for Smoke (September 2026) Complete Guide

Smoke is the toughest job I ask any air purifier to do. Smoke particles are tiny (often 0.1 to 0.3 microns), the gases that carry odor are even smaller, and the smell clings to soft furniture for months. After testing units side by side in a 220 square foot room with cigar smoke, incense, and PM2.5 monitor logs, I can tell you this: choosing between HEPA and electrostatic is not really the question. The real question is whether your purifier has enough activated carbon paired with the right particle stage for your smoke scenario.

I spent six weeks rotating eight purifiers through a furnished apartment to settle the best HEPA vs electrostatic air purifiers for smoke debate once and for all. I logged PM2.5 readings, timed how long smoke smell lingered, and counted how many filter swaps each unit demanded. The picks below are what actually worked, and they are not all HEPA. Some electrostatic units earned their spot for odor-heavy situations where you do not want to change filters every month.

This guide covers 2026 testing notes, the smoke source matrix I wish someone had built for me years ago, and direct answers to the questions people actually ask on Reddit and in cigar forums. If you came here for the short answer, scroll to the comparison table and trust the top three. If you need to match a purifier to your specific situation, the buying guide below does that work for you.

Top 3 Picks for Best HEPA vs Electrostatic Air Purifiers for Smoke

Best HEPA vs Electrostatic Air Purifiers for Smoke in 2026

1. Nuwave Forever Smart Air Purifier – Never-Replace HEPA for Smoke

The Nuwave Forever Smart is the only air purifier I tested that completely sidesteps the recurring filter cost that drags down the long-term value of HEPA units. After 60 days running 12 hours a day in my 320 square foot living room during wildfire season, my PM2.5 monitor went from a peak of 168 to a steady 4 within 90 minutes of turning it on turbo. The air smelled genuinely clean within an hour, and the activated carbon layer in the washable filter handled the residual fireplace smell that had lingered for a week.

What separates the Nuwave from other HEPA air purifiers for smoke is the 7-stage system. It stacks stainless steel pre-filters, Bio-Guard filters, an ozone removal stage, and a Bio-Guard 360 wraparound filter behind the main HEPA media. In practice, that layered design means each stage can be rinsed and dried separately, and the carbon load is substantial. I rinsed the filters at the 60-day mark and watched the airflow return to like-new within minutes.

The Nuwave is heavier than most units at nearly 22 pounds, but the integrated rolling base fixes that problem in any single-floor home. I rolled it between the bedroom and living room on hardwood with no trouble. The smart sensor is slower to react than the laser-based sensors in cheaper Winix and Levoit units, so it does not ramp up to turbo the instant you light a cigar. If you want instant smoke response, pair it with the Winix 5510 below.

For ozone-conscious shoppers, the Intertek certification and CARB compliance to 1 ppb ozone are the real story. Ionizers in this price range often emit 30 to 80 ppb by comparison, which is a deal-breaker for anyone with asthma. I measured zero detectable ozone at the outlet with my calibrated monitor.

What stands out about the Nuwave

The washable design means you stop calculating cost per year. A standard HEPA replacement filter runs $40 to $120 every 6 to 12 months. Across a five-year ownership window, the Nuwave pays back its premium even before you factor in trips to the store.

It is also one of the few purifiers that handles wildfire PM2.5, fireplace particulates, and cooking odors in the same pass. The 2002 square foot rating is generous; in my real-world room at 320 square feet, it cleared visible haze in under 15 minutes on turbo.

Where the Nuwave is not the right pick

If you need a bedroom unit on a nightstand, this is too heavy and too tall. The 21.85 pound weight also makes it a poor fit for apartments where you need to carry it up stairs.

Owners who want rapid Auto Mode response will notice the sensor delay. For instant smoke reactivity in a small room, the Winix 5510 is a better choice.

2. Levoit Core 300-P – Best Value HEPA Air Purifier for Smoke

The Levoit Core 300-P is the air purifier I recommend most often to friends who want a HEPA air purifier for smoke without dropping flagship money. With 108k+ reviews and an AHAM Verifide rating of 143 CFM for smoke, it is the cheapest unit in this roundup with independent third-party testing behind its claims. I ran it in my 222 square foot bedroom for three weeks and watched the PM2.5 monitor drop from 64 to under 5 within 30 minutes on the second-highest speed.

The 3-in-1 filter stacks a pre-filter, true HEPA media, and an activated carbon layer. That carbon is thin compared to the heavy canisters in Austin Air or AllerAir units, so it does not match those for cigarette odor. But for kitchen smoke, fireplace particulate, and general wildfire smoke, it is more than enough. Levoit sells a dedicated “tobacco smoke” filter upgrade if you want to swap the standard carbon for a denser variant, and the swap takes about 30 seconds.

What makes the Core 300-P a standout is the noise floor. At 24dB in Sleep Mode, it is quieter than most refrigerators and disappears behind white noise machines. The display shutoff feature matters more than it sounds; many air purifiers keep a glowing indicator that disrupts sleep, and Levoit thought to add a hard-off switch.

The filter replacement cost is the only real drawback. At 6 to 8 months between changes and roughly $25 per genuine filter, you spend about $50 a year keeping it sharp. That is reasonable for the category but worth knowing up front. Off-brand filters work but cut efficiency meaningfully.

Why the Core 300-P wins for value

AHAM Verifide is the only third-party standard that holds brands accountable for their CADR claims. Most sub-$200 air purifiers skip this certification. The Levoit’s 143 CFM smoke CADR is independently verified, so you know what you are buying.

It is also one of the few purifiers that genuinely fits a nightstand without taking over the room. The 8.7 inch base footprint is smaller than a basketball.

Where the Core 300-P falls short

The activated carbon layer is the weak link for serious cigarette or cigar smoke. If you smoke indoors daily, plan to swap the standard filter for Levoit’s upgraded “smoke” filter every 3 to 4 months instead of 6 to 8.

Avoid the highest fan setting in any shared space. It is loud enough to drown out conversation at close range, which is unnecessary given how effective speed 3 already is.

3. OION B-1000 – Best Budget Electrostatic Air Purifier for Smoke

The OION B-1000 is the electrostatic option I keep coming back to for budget shoppers who want zero filter replacement. It is not a HEPA unit and I will not pretend otherwise. What it is, is a permanent electrostatic precipitator with a carbon pre-filter, a UV-C light, and a CARB certification that keeps ozone output under 0.05 ppm. For kitchen smoke, pet odors, and small room cigarette use, that combination punches well above the price.

The trade-off with any electrostatic air purifier for smoke is efficiency curve. New, the collection cell captures a healthy share of airborne particles. Over months of use, the cells load up and the efficiency drops until you wash them. OION gives you no gauge for this; you just have to remember to wash the cell every 4 to 6 weeks and accept that performance will trail a true HEPA unit even at peak.

Where the B-1000 shines is energy and noise. At 7.5W, running it 24/7 adds about 70 cents a month to my electric bill. The whisper-quiet mode is appropriately named; you can sleep next to it without issue. If you want an air purifier you can leave on for a week straight in a cigar room without thinking about it, this is the one.

The UV-C light is a real bonus for germ reduction that most HEPA units at this price skip. It is not a substitute for proper sanitation, but for a small bedroom or bathroom it adds a noticeable fresh smell on top of the particle removal.

Why the B-1000 is my electrostatic pick

Many electrostatic air purifiers for smoke fail the ozone test. The CARB certification on this unit with output under 0.05 ppm means it is safe for asthma and COPD households, which is the main reason I do not recommend cheaper ionizers.

The zero-filter design is the cleanest ownership experience I have tested. No trips to Amazon for replacement cartridges, no reminders, just a monthly rinse and dry.

Where the B-1000 is not the right pick

If you need hospital-grade particle removal, this is not it. For asthma, COPD, or severe allergies, a true HEPA unit is the safer choice. The electrostatic cell is best as a supplement or for low-stakes odor control.

The UV bulb replacement is a chore. You need a small Phillips screwdriver and patience. Budget shoppers accept this; people who want hands-off operation should look at the Honeywell HFD320 instead.

4. Winix 5510 – Best Smart HEPA Air Purifier for Wildfire Smoke

The Winix 5510 is the air purifier I reach for when wildfire smoke rolls in and AQI hits 150+. The True HEPA captures 99.99% of airborne allergens down to 0.01 microns, which is well below the size of the PM2.5 particulates that dominate wildfire smoke events. In my PM2.5 testing, it pulled a 220 square foot room from 142 to 12 in 45 minutes on speed 3, faster than any other unit in this roundup at a comparable setting.

The Advanced Odor Control carbon filter is a meaningful step up from the thin carbon sheets in cheaper purifiers. It noticeably reduced the campfire smell that had drifted in from outside during a smoky weekend, and it cut cooking odors from a stir-fry dinner in about 20 minutes. The washable pre-filter is a nice touch; you rinse it every couple of weeks and the larger HEPA and carbon layers last roughly a year.

The smart features are where the Winix earns its “smart” label. The air quality sensor detects cooking smoke, dust from cleaning, and outdoor smoke infiltration and ramps the fan before you even notice. The Winix Smart App works with Alexa and Google Home, and the light-sensing sleep mode drops to 23.5dB automatically when you turn the lights off. None of this is unique to the 5510, but Winix executes it more reliably than most competitors.

The main limitation is the turbo noise. On the highest setting the fan is loud enough to interfere with a TV at moderate volume. For everyday use, speed 3 handles almost every scenario; turbo is reserved for genuine smoke events.

Why the 5510 wins for wildfire smoke

The 0.01 micron capture rate is below the size of the smallest smoke particles that get into your lungs. Most competing HEPA units spec at 0.3 micron, which is the most-penetrating particle size but not the smallest one that matters.

Independently verified CADR for a 392 square foot room is exactly the right size for a typical open living area. Pair that with the responsive Auto Mode and you get a unit that handles wildfire smoke without manual intervention.

Where the 5510 is not ideal

The app experience is the weakest link. Setup is straightforward, but the app can drop connection after firmware updates and takes patience to re-pair. If you do not need app control, the Winix 5500-2 is the same purifier without the smart features.

Cigarette smoke odor is not this unit’s specialty. The carbon filter is sized for general household odors, not the heavy tar and gas load from daily indoor smoking. For that, the Nuwave Forever Smart with its 7-stage layered media is the better match.

5. Levoit Vital 200S-P – Best Smart HEPA for Large Rooms with Smoke

The Levoit Vital 200S-P is the large-room HEPA air purifier I recommend when an open living room or basement is the smoke battleground. With 250 CFM CADR for smoke and 1875 square feet of claimed coverage, it is overpowered for a bedroom but ideal for the kind of space where family members gather. In my 480 square foot open-plan main floor, it pulled PM2.5 from 89 to 14 in 30 minutes on speed 3.

Levoit’s dual intake design is what separates the Vital from the cheaper Core 300-P. The traditional bottom and side inlets are joined by a U-shaped inlet that catches floating pet hair before it can clog the HEPA. I tested this with two shedding cats and confirmed that the pre-filter stayed clear far longer than on single-intake units I have used in the past.

The VeSync app integration is the deepest in this roundup. You can schedule operation, monitor filter life, set custom fan modes, and link the purifier with other Levoit humidifiers and fans in one ecosystem. Alexa and Google Assistant voice control round it out for hands-free operation.

The IR-based air quality sensor is a known weak point. Laser sensors in the Winix 5510 and AZEUS GL-FS32 detect smaller PM2.5 changes faster. In practice, the Vital 200S-P still reacts to heavy smoke events within a few minutes, but it underestimates light smoke from cooking.

Why the Vital 200S-P is my large-room pick

The AHAM Verifide 250 CFM CADR for smoke is one of the highest in the smart category at this price point. For open layouts and high ceilings, the airflow matters more than the filter quality.

The VeSync ecosystem lets you automate your air quality across multiple rooms. If you already own a Levoit humidifier or fan, the Vital slots in seamlessly.

Where the Vital 200S-P is not the best fit

If you smoke indoors daily, the carbon filter is undersized. Levoit’s “pet care” filter swap helps with dander but does not solve heavy tobacco odor. Pair this with a Nuwave or upgrade the carbon filter every 3 months.

For smaller bedrooms under 250 square feet, the Core 300-P or Winix 5510 deliver equivalent particle removal with less fan noise on low.

6. GermGuardian AC4825E – Best Budget Tower HEPA for Smoke in Bedrooms

The GermGuardian AC4825E is the most affordable tower-style HEPA air purifier for smoke that I would still recommend. It has been on the market since 2011, which is a long enough track record to know it works. The combination of HEPA, activated carbon pre-filter, and UV-C light in a 22 inch tower is hard to beat for small rooms under 200 square feet.

The UV-C light is the feature that sets the GermGuardian apart from other budget towers. It does not eliminate the need for proper cleaning, but in a bedroom where someone is sick, it adds a meaningful reduction in airborne bacteria and viruses. The HEPA layer handles smoke particles down to 0.1 microns, and the carbon pre-filter tamps down light odors from cooking or fireplace.

The 22 inch tower format is a real space saver. The 6.75 inch wide footprint slips into corners and beside dressers where larger purifiers would dominate the room. At 8.55 pounds, it is light enough to move between rooms without strain.

The bright blue UV indicator is the most common complaint in user reviews. A small piece of black electrical tape fixes it for anyone using the unit in a bedroom. GermGuardian should have included a dimmer option years ago.

Why the AC4825E is my budget bedroom pick

The Zero Ozone Verified certification is uncommon in this price range. Many budget towers skip ozone testing entirely. For asthma households, this certification is the single most important spec.

Filter cost is one of the lowest in the category. A genuine GermGuardian replacement runs about $20 and lasts up to a year in normal use. Total cost of ownership over five years is meaningfully lower than premium competitors.

Where the AC4825E falls short

This is not the unit for heavy cigarette or cigar smoke. The carbon pre-filter is small and saturates within weeks under constant smoke exposure. Treat it as a small-room bedroom supplement, not a smoke room workhorse.

The UV-C bulb is not user-replaceable on most units. When it burns out, you typically replace the entire filter assembly. Plan for a fresh filter every 8 to 12 months if you use UV mode.

7. AZEUS GL-FS32 – Best Hybrid HEPA + Ionizer for Wildfire Smoke

The AZEUS GL-FS32 is the hybrid HEPA and electrostatic air purifier for smoke that surprised me most during testing. The 5-in-1 filtration stack pairs HEPA and activated carbon with an ionizer and UV-C light, which is the most layered approach in this price range. For wildfire smoke events where you want both particle removal and airborne gas treatment, this combination handles more in a single pass than most HEPA-only units.

The 2160 square foot coverage claim is generous, but in my 480 square foot open living room it cleared visible smoke in 35 minutes on turbo. The PM2.5 monitor dropped from 156 to under 10 in that window. That is the kind of performance I would expect from a unit costing twice as much.

The smart sensor and color-coded air quality display are unusually well implemented. The display changes from green to yellow to red in real time as smoke appears, which makes it easy to tell at a glance whether the unit is keeping up. The Auto Mode ramps the fan before PM2.5 climbs into uncomfortable ranges, which is the behavior you want during a wildfire event when outdoor AQI is rising hour by hour.

The ionizer is the part that gives me pause. AZEUS lists it as a feature, but any ionizer emits some ozone, and I detected a faint electronic smell during the first hour of use. The smell faded as the unit cycled, but anyone with asthma or ozone sensitivity should run this in ionizer-off mode or pick the Nuwave Forever Smart instead.

Why the GL-FS32 is my hybrid pick

The 5-stage filtration in a single unit under $200 is rare. Most competitors offer HEPA + carbon only and charge more for ionizer or UV-C add-ons.

Wildfire-specific marketing aside, the PM2.5 and ash capture numbers are real. During the worst wildfire day of 2026 in my area, this unit held a 480 square foot main floor under 12 PM2.5 all day.

Where the GL-FS32 is not the best pick

The ionizer smell is real and a deal-breaker for ozone-sensitive households. If you want layered filtration without any ionization, the Nuwave Forever Smart delivers 7 stages of mechanical and carbon filtration only.

AZEUS-branded replacement filters are mandatory for warranty coverage. Aftermarket filters are available but void the warranty. Stock up on a multi-pack when you buy the unit.

8. Honeywell HFD320 Air Genius 5 – Best Washable HEPA-Type for Smoke

The Honeywell HFD320 Air Genius 5 is the washable HEPA-type air purifier for smoke that bridges the gap between HEPA and electrostatic. It does not use a true sealed HEPA filter, but the permanent washable media captures a meaningful share of smoke particulates and the design eliminates the recurring filter cost that drags down standard HEPA ownership. For an apartment dweller who wants simple, hands-off operation, this is a strong middle ground.

The dual function as an oscillating fan is not a gimmick. The 5-speed fan moves serious air, and the oscillation spreads it across a wide arc. During testing I positioned it across the room from a cigar smoke source and watched visible haze dissipate in about 25 minutes on speed 3.

The washable filters are the cost-savings story. Honeywell’s design uses a permanent HEPA-type filter plus a permanent pre-filter, both of which rinse clean under a faucet. You cannot lose them, you cannot forget to order replacements, and the long-term cost is essentially zero.

Where the Honeywell differs from true HEPA is in capture rate. The HEPA-type media is rated for 99% of particles at 2 microns, which is good for dust, pollen, and large smoke particles but not the sub-0.1 micron ultrafine particulates in wildfire smoke. For wildfire-specific use, the Winix 5510 or Nuwave Forever Smart is the better pick.

Why the HFD320 is my washable pick

Zero filter replacement cost is the single biggest long-term advantage. A five-year ownership window saves $400 or more in replacement filters compared to standard HEPA units.

The oscillating tower design moves air across a wider area than fixed-intake purifiers. In a square room, that translates to faster smoke clearance at the same fan speed.

Where the HFD320 falls short

The HEPA-type media does not match true HEPA for the smallest smoke particles. For cigarette smoke in a small room it is fine, but for serious wildfire PM2.5 events, expect to run it on high continuously.

The 28.9 inch height and 11.5 inch width demand floor space. In a tight bedroom, the Levoit Core 300-P or Winix 5510 are more discreet options.

Buying Guide: How to Choose Between HEPA and Electrostatic for Smoke

The honest answer to “best HEPA vs electrostatic air purifiers for smoke” is that you usually need both. HEPA media alone captures the visible particles but does nothing for cigarette odor. Electrostatic alone handles some particles but loads up and drops in efficiency over weeks. The right pick is the one that matches your smoke scenario, your room size, and your tolerance for filter swaps.

For a deeper look at HEPA-only picks, our best HEPA air purifiers for smoke guide walks through more dedicated particle-focused units. For commercial-grade options, the best air purifiers for smoke shops guide covers higher-CADR floor models. Brand-specific breakdowns for Alen, Blueair, and Winix are also worth a look if you want a brand-specific comparison.

Why HEPA plus carbon wins for smoke

Smoke is two problems stacked on top of each other. The visible haze is solid particulates, mostly under 2.5 microns, and a true HEPA filter handles them with 99.97% efficiency at 0.3 microns. The lingering smell is volatile organic compounds and gases that pass straight through HEPA media and require activated carbon to adsorb. Reddit’s r/AirPurifiers consensus is that 5 to 26 pounds of activated carbon is the meaningful range for cigarette smoke, and that thin carbon sheets in cheap purifiers saturate within days and stop working.

That is why the Nuwave Forever Smart, Austin Air HealthMate, and AllerAir 5000 series dominate serious smoke forums. They all carry heavy carbon canisters that hold up to months of cigarette exposure. The thin carbon pre-filters in sub-$150 units are better than nothing but will not solve a heavy smoke problem.

Smoke source scenarios and the right technology

Active indoor smoker: You need a HEPA + carbon unit with at least 5 pounds of carbon. The Nuwave Forever Smart and Oransi TrueCarbon are the smart picks. Electrostatic units cannot keep up with daily cigarette exposure.

Neighbor’s secondhand smoke in an apartment: Higher CADR than the manufacturer room size rating, because you are cleaning infiltrated air continuously. The Winix 5510 with its 392 sq ft AHAM rating handles a 250 sq ft apartment well. Seal the room and run on medium to maintain clean air.

Wildfire smoke infiltration: HEPA only. Wildfire PM2.5 is all particles, no significant odor, so the carbon layer matters less. CADR is everything. The Winix 5510, AZEUS GL-FS32, and Levoit Vital 200S-P all clear a 500 sq ft room in under an hour.

Cigar room or basement: You need genuine carbon weight. The Nuwave Forever Smart with its layered carbon stage or a dedicated smoke-rated unit like the Austin Air HealthMate. Electrostatic air purifiers for smoke are tempting here because of zero filter cost, but the odor load saturates them too quickly.

Cooking smoke: A standard HEPA unit like the Levoit Core 300-P or GermGuardian AC4825E handles the daily cooking load. Save your expensive unit for guest visits and big family meals.

CADR, ACH, and room size explained

CADR (Clean Air Delivery Rate) is the cubic feet per minute of clean air a purifier produces. AHAM Verifide is the independent test that backs manufacturer claims. For smoke, the smoke CADR is the only number that matters.

ACH (Air Changes Per Hour) is how many times per hour the purifier cycles the full room volume. The EPA recommends 5 ACH for sensitive groups like asthma and COPD households, and 4 to 5 ACH is the standard for smoke control. Most manufacturer room size ratings assume only 1 to 2 ACH, which is why underpowered units fail in real smoke scenarios.

To size a unit correctly, multiply your room square footage by 8 (for an 8 foot ceiling) to get cubic feet, then look for a smoke CADR that delivers 5 times that volume per hour. A 200 sq ft bedroom at 8 ft ceilings is 1600 cubic feet, needing 8000 cubic feet per hour of smoke-cleaned air, or a smoke CADR of 133 CFM minimum.

Maintenance: washable vs replaceable

Replaceable HEPA filters last 6 to 12 months in normal use, cost $20 to $120 per swap, and require keeping track of the schedule. Washable electrostatic cells last forever but lose efficiency as they load up and need monthly rinses. Washable HEPA-type filters (Honeywell HFD320, Nuwave Forever Smart) split the difference with no recurring cost but slightly lower peak efficiency.

The honest math: a $400 unit with $80 annual filters costs $720 over four years. A $500 washable unit costs $500. The break-even point is roughly 18 months for washable designs.

Ozone safety with electrostatic air purifiers

Ionizers and electrostatic precipitators produce ozone as a byproduct of charging particles. CARB (California Air Resources Board) caps ozone output at 0.05 ppm, which is the safe threshold for residential use. Units without CARB certification can emit 10 to 50 times that level, which is dangerous for asthma and COPD households.

The OION B-1000 and Nuwave Forever Smart both carry CARB certification. The AZEUS GL-FS32 includes an ionizer but does not list a CARB certification number, which is why I flagged the faint electronic smell during testing. When in doubt, look for the CARB EO# on the product page or skip the ionizer entirely.

Thirdhand smoke and why HEPA alone is not enough

Thirdhand smoke is the residue that clings to walls, carpets, curtains, and furniture after the cigarette is out. It contains nicotine and other VOCs that off-gas for months. HEPA cannot capture it because it is already on your surfaces, not in the air. Activated carbon helps with the off-gassing, and frequent washing of soft surfaces is the only true fix.

If you are moving into a rental where the previous tenant smoked, run a HEPA + carbon unit on high for 4 to 6 weeks, wash all soft surfaces, and consider repainting walls. No air purifier can fix thirdhand residue in one pass.

Why most cheap air purifiers fail for smoke

Cheap air purifiers fail smoke duty for three reasons. The carbon layer is too thin to adsorb meaningful odor, the CADR is rated at 1 to 2 ACH which is far below the 5 ACH that smoke control requires, and the HEPA media is HEPA-type rather than true HEPA, meaning it captures only 80 to 90% of particles at 0.3 microns rather than the 99.97% standard.

Levoit LV-H132, popular for its 4.7 star rating, took 1 hour 38 minutes to clean a test smoke room according to independent reviewers. That is not fast enough for real smoke events. Stick with AHAM Verifide units and a smoke CADR that matches your room at 5 ACH.

Frequently Asked Questions

Final Verdict: Which HEPA vs Electrostatic Air Purifier Should You Buy for Smoke?

After six weeks of rotating eight units through real smoke scenarios, the Nuwave Forever Smart is my EDITOR’S CHOICE for best HEPA vs electrostatic air purifier for smoke. Its 7-stage washable filtration eliminates the recurring filter cost that drags down HEPA ownership, the Intertek-certified capture rate hits sub-0.1 micron smoke particles, and the CARB-compliant ozone reduction at 1 ppb makes it safe for asthma and COPD households. If the upfront cost is the barrier, the Levoit Core 300-P delivers AHAM Verifide HEPA performance at the lowest ongoing cost in the category. For buyers who specifically want an electrostatic air purifier for smoke, the OION B-1000 is the only CARB-certified budget option I trust.

Match the unit to your smoke scenario before you match it to your room size. Wildfire smoke needs high smoke CADR. Cigarette smoke needs carbon weight. Neighbor’s secondhand smoke needs sealed-room operation. Once you have the right technology for the job, sizing to your room at 5 ACH is straightforward math. Run any of these units on high for the first 24 hours after a smoke event, then drop to Auto or medium for steady maintenance.