Blueair 311i Max Review: CADR, HEPASilent, Ozone, Filters and Alternatives

The Blueair Blue Pure 311i Max is a medium-room purifier for a bedroom, nursery or living room up to about 439 sq ft. Blueair rates it at 283 cfm of smoke CADR, ENERGY STAR’s record matches, and it draws only 32 W at full speed, for around $230. The trade-off is HEPASilent: electrostatic charging helps the filter, you can’t switch it off, and CARB lists the purifier as an electronic air cleaner. We’d buy it for a bedroom or medium living room if a small, documented ozone reading doesn’t bother you.

This review is research-based, not a test of our own. Every number below comes from Blueair’s product page, the ENERGY STAR Version 3.0 data set and the CARB certified list. Blueair isn’t in the AHAM Verifide directory, so the CADR figures are Blueair’s own, cross-checked against ENERGY STAR. Our research method explains how we work.

Blueair 311i Max specs at a glance

Spec	Blueair Blue Pure 311i Max	Source
CADR (smoke / dust / pollen)	283 / 314 / 365 cfm	Blueair (matches ENERGY STAR, SKU 3332111100)
Room size	439 sq ft at 4.8 air changes per hour	Blueair
Filter	One cylindrical filter: washable fabric pre-filter, particle media, carbon layer	Blueair
Technology	HEPASilent (electrostatic charging plus filter media)	Blueair
CARB	Certified (SKU 3332111100, Electronic, EO G-23-050)	CARB
Ozone	2 ppb	ENERGY STAR
Noise	23 to 50 dB	Blueair
Power	32 W max	Blueair
ENERGY STAR	Yes (V3.0, 9.59 smoke CADR/W, 193 kWh/yr)	ENERGY STAR
Smart features	Wi-Fi, Blueair app (remote control, timer, filter alerts), air sensors, Auto and Night modes, 3 speeds	Blueair

How much air does the 311i Max clean?

Blueair rates the 311i Max at 283 cfm for smoke, 314 for dust and 365 for pollen, and ENERGY STAR’s record for the same SKU matches. Older Blueair and retailer pages cite about 250 cfm and 387 sq ft; those figures are out of date, so use the current ones.

Blueair’s 439 sq ft matches AHAM’s own formula (smoke CADR x 1.55), which works out to about 4.8 air changes per hour with an 8 ft ceiling. AHAM’s simpler rule of thumb, a smoke CADR of at least two-thirds of the floor area, puts the ceiling at roughly 425 sq ft. That’s a large primary bedroom or a 15 x 25 ft living room. For wildfire smoke, AHAM suggests a smoke CADR equal to the room’s square footage, which would cap the 311i Max at about 283 sq ft during smoke events.

Ignore the 1,054 sq ft (in 30 minutes) and 2,107 sq ft (in one hour) figures on Blueair’s page. They’re based on two air changes and one air change per hour, so they can’t be compared with 4.8-ACH room sizes. To check your own room, use our air purifier size calculator, and read what CADR is for how the test works. Like every CADR, these numbers are measured at top speed; on Night mode it cleans less air.

HEPASilent, electrostatic charging and ozone

HEPASilent is Blueair’s name for combining electrostatic charging with mechanical filter media. It’s the reason the 311i Max is grouped with ionizing purifiers by regulators, even though it has no separate ionizer button.

CARB certifies the 311i Max (SKU 3332111100, EO G-23-050, March 2023) as electronic, which means it emits no more than 0.050 ppm (50 ppb) of ozone. ENERGY STAR, which also caps ozone at 50 ppb for certified models, lists a measured 2 ppb. That’s a small number, but it isn’t zero, and Blueair’s page shows no setting to turn the charging off.

EPA notes that air cleaners using ionizers or electrostatic precipitators may emit ozone, a lung irritant. In our view the 311i Max’s documented reading is low enough for most homes, but if anyone in the household is sensitive to ozone, or you’re setting up a nursery, a mechanical-only purifier is the safer choice. Our guides to the ionic air purifier and the air purifier for a baby room explain the background.

Important: HEPASilent is not a True HEPA claim. The US DOE defines HEPA as at least 99.97% efficiency at 0.3 µm, and none of the sources we rely on publish such a figure for the 311i Max. Compare it with other purifiers by CADR.

Filters: what’s inside and what they cost

The 311i Max uses one cylindrical filter with a particle layer and a carbon layer, wrapped in a fabric pre-filter. Blueair says to replace the main filter up to every 9 months and sells three versions:

• Particle + Carbon (#110037), the standard filter for light household odors, around $45
• SmokeBlock (#111236), with “2x more activated carbon” per Blueair, around $60
• AllergenBlock (#111228), around $65

Replacement fabric pre-filters cost around $11. The pre-filter is the only washable part, which helps with pet hair and lint; the main filter can’t be washed.

Blueair publishes no carbon weight for any version. EPA notes that thin carbon layers saturate quickly, so the standard filter suits everyday cooking and household smells, not heavy smoke odor or VOCs. If smoke is the main reason you’re buying, get the SmokeBlock filter, and see our HEPA vs carbon filter guide for why the amount of carbon matters.

Noise, controls and running cost

Blueair rates the 311i Max at 23 dB on its lowest setting and 50 dB at the top of its three speeds. Air sensors drive Auto mode, and Night mode is there for bedrooms. The Blueair app adds remote control, a timer and filter alerts over Wi-Fi.

Power is its strongest spec. Blueair lists 32 W at maximum, and ENERGY STAR rates it at 9.59 smoke CADR per watt with an estimated 193 kWh a year. At the US average of 18.31 cents per kWh (EIA, July 2026), our math gives:

• ENERGY STAR’s estimate: about $35 a year
• Top speed, around the clock: about 280 kWh, or roughly $51 a year
• Top speed, 8 hours a night: roughly $17 a year

Try your own hours and rate in the air purifier electricity cost calculator. At Blueair’s 9-month interval, the standard filter adds roughly $60 a year.

Blueair 311i Max vs 211i Max, Levoit Vital 200S and Coway AP-1512HH

	311i Max	211i Max	Levoit Vital 200S-P	Coway AP-1512HH
Smoke CADR	283 (Blueair)	435 (Blueair)	250 (AHAM)	233 (Coway)
Room size	439 sq ft	674 sq ft	388 sq ft	361 sq ft
Max power	32 W	46 W	52.4 W (AHAM)	77 W
Ozone tech	Electrostatic (CARB electronic)	Electrostatic (CARB electronic)	None (CARB mechanical)	Ionizer, can be switched off
Filter life	Up to 9 months	Up to 9 months	6 to 12 months	Carbon 6, HEPA 12 months

Blueair Blue Pure 311i Max

The 311i Max is the one to get for a bedroom or medium living room when you want a cross-checked CADR on very little power, a washable fabric pre-filter and an app, at around $230. The trade-offs are electrostatic charging you can’t turn off, a 9-month filter interval and no published carbon weight.

Blueair also sells a higher-output 311i+ Max. ENERGY STAR lists it at 339 smoke, 364 dust and 408 pollen CADR for 525 sq ft, and it sells for around $255 on sale ($300 list). It fits rooms between the 311i Max and 211i Max.

Check the Blueair 311i Max on Amazon

Blueair Blue Pure 211i Max

The 211i Max is the same design at a larger scale. Blueair lists 435 smoke, 452 dust and 450 pollen CADR for 674 sq ft, and it draws 46 W at max. It adds a fourth speed, PM1/PM2.5/PM10 sensing and Alexa and Google Home support. Filters are around $70 and last up to 9 months, and the unit is around $350. It shares the same caveat: CARB lists it as electronic and ENERGY STAR measured 2 ppb of ozone. We’d pick it over the 311i Max only for a room bigger than about 425 sq ft. For a large-room purifier without electrostatic charging, our Levoit Core 600S review covers an alternative.

Check the Blueair 211i Max on Amazon

Levoit Vital 200S-P

If you’d rather have no ionizing or electrostatic stage at all, the Vital 200S-P is the alternative we’d look at. AHAM lists 250 smoke CADR for 388 sq ft, a little less than the 311i Max, and CARB certifies it as mechanical. It has a washable pre-filter, an infrared dust sensor with Auto mode, a Pet Mode and app control, and Levoit gives a 6 to 12 month filter interval. It costs around $190. The catch is power: AHAM measured 52.4 W at max, and it isn’t ENERGY STAR certified.

Check the Levoit Vital 200S-P on Amazon

Coway Airmega AP-1512HH Mighty

The AP-1512HH covers a similar room (233 smoke CADR and 361 sq ft, both from Coway) and has a True HEPA filter, a washable pre-filter and a separate carbon filter. Its ionizer can be switched off, but it draws 77 W at max and has no app. Coway’s own store showed it as sold out or unavailable in October 2026, so check stock. Our Coway Airmega AP-1512HH review covers it in detail.

Who the 311i Max suits, and who should skip it

Good fit:

• A bedroom or living room up to about 425 sq ft
• Anyone who wants low running costs and a quiet bottom speed
• Homes with pets, thanks to the washable fabric pre-filter

We’d skip it if:

• You don’t want any electrostatic or ionizing stage in the house (look at the Levoit Vital 200S-P)
• Your room is bigger than about 425 sq ft (the 311i+ Max or 211i Max fits better)
• You need heavy odor or smoke removal on the standard filter; at minimum, switch to SmokeBlock

For more bedroom options, see our guide to the best air purifier for a bedroom.

Note: An air purifier can reduce airborne allergens, dust and smoke particles, but it doesn’t replace removing the source or ventilating. If you’re buying for asthma or allergies, talk to your doctor about what else will help.

Our verdict

On paper, the Blueair Blue Pure 311i Max is one of the most efficient medium-room purifiers you can buy: a 283 smoke CADR that ENERGY STAR confirms, about 439 sq ft of coverage, and only 32 W at full speed. The weak points are electrostatic charging with no off switch, which makes it a CARB electronic unit even though its measured ozone is low, a filter that lasts up to 9 months, and thin carbon in the standard filter. Our pick for a bedroom or medium living room is still the 311i Max if you’re comfortable with that trade-off; if you’re not, the mechanical-only Levoit Vital 200S-P is the safer choice.