Best Air Scrubber for Mold Remediation: 8 HEPA Machines Compared by CFM, Filter and Price

How we made this guide: picks, prices and specs come from our catalog and the makers' published specs, owner quotes come from customer reviews on our product pages and every guide is checked and edited by Trevor Hall.

The best air scrubber for most mold remediation jobs is the Abatement HEPA-AIRE H2KM at $1,070: a HEPA machine rated at 2,000 CFM that you can duct out of the containment as a negative air machine, and our best-selling negative air machine. For a lower-priced pick, the AlorAir PureAiro HEPA Pro 970 is $799 and for large rooms the Abatement PAS5000 goes up to a rated 4,000 CFM at $6,800.

Quick picks: eight HEPA machines for mold jobs

Each CFM figure is the maker's rating; the condition column shows how it was measured.

What matters when you choose an air scrubber for mold

Ductability comes first. A scrubber that only recirculates air inside the work area cleans the room it sits in. A negative air machine exhausts through a duct to the outdoors, which holds the containment at negative pressure to the rooms around it. The EPA's mold remediation guide for schools and commercial buildings describes the same setup: a HEPA-filtered fan unit exhausted outside the building. Most machines here take a duct collar: the H2KM, the 9103 (12 in exhaust), the NOVAIR 1000 (10 in collar), the HEPA Pro 970 (8 in outlet) and the X-3400A when you attach a hose to the exhaust. Our guide to air scrubber vs negative air machine covers the setup difference, and what a negative pressure room is covers the pressure side.

The CFM number needs its condition. A rating taken without loaded filters will always read higher than the airflow you get at the end of a dirty job, so call every number rated and size with room to spare.

Filter rating, as the maker states it. Four of the eight list 99.97% at 0.3 micron. HEPACART lists 99.99% at 0.3 micron with the HEPA stage mounted after the fan. AlorAir lists up to 99.95% of particles 0.3 micron and larger. Aeroclean and XPOWER list the HEPA stage without an efficiency figure. For the standard behind these numbers, read what a HEPA filter is.

Power. The big boxes want a 15 A circuit (H2KM, PAS1200UV) or a dedicated 10 A circuit (NOVAIR 1000). The PAS5000 lists 230 V and 30 A. The X-3400A and the HEPA Pro 970 each list 2.8 A. Our calculation: three on one 15 A circuit is 3 x 2.8 = 8.4 A. Stay inside each maker's chaining limit: AlorAir lists up to three units on the 970's outlet.

Air changes per hour. ACH = CFM x 60 / room volume in cubic feet. Take a 12 x 20 ft containment with 8 ft ceilings: 1,920 cubic feet. The NOVAIR 1000 on low, rated at 500 CFM with all filters installed, gives 500 x 60 / 1,920 = about 15.6 air changes per hour. That is our calculation from a rated figure, and real airflow through loaded filters and long duct runs is lower.

Best overall: Abatement HEPA-AIRE H2KM

The H2KM is the machine we would put in most mold containments. Abatement lists two speeds, 2,000 CFM high and 1,300 CFM low, with a 6 in deep HEPA filter listed at 99.97% at 0.3 micron and an optional 12 in HEPA. It runs on a 115 to 120 V, 15 A circuit with a starting draw of 10 A or less. The cabinet is 20-gauge galvanized steel with four locking swivel casters, and a lamp tells you when the filters need changing.

Two prefilters, a polypad and a 2 in pleat, sit ahead of the HEPA. Our Abatement air scrubber range holds the other models if you want a variant.

Skip it if you work in tight houses with narrow stairs and small containments.

Best with an alarm and gauge: Aeroclean Full Feature 9103

The 9103 is rated at 2,000 CFM on high and 1,500 CFM on low at 1.9 in running static pressure, one of only two ratings here that state their condition. The controls include a differential pressure gauge, a push-button breaker, a two-speed switch and a red warning light with an audible alarm. It runs on 115 V and draws 9.4 running amps.

It weighs 108 lb and uses 24 x 24 in filters: a pad prefilter, a ring panel and the HEPA. The gauge and alarm read pressure across the filters, so they warn you when the filters load up before airflow falls off unnoticed. They do not measure the containment. To confirm negative pressure you still need a room pressure monitor such as the Abatement RPM-RT1; what a negative pressure room is covers the targets.

Skip it if you do not need the alarm and want the lower price of a smaller machine.

Best compact negative air machine: Novatek NOVAIR 1000

Novatek rates the NOVAIR 1000 at 1,000 CFM on high and 500 CFM on low with all filters installed. Buy a HEPA version for mold: the F1000 is listed at 99.97% at 0.3 micron. The standard version uses a general purpose 5 micron filter and is not a HEPA machine. Hour meter, alarm and light versions run from $1,154 to $1,275.

It is 94 lb with HEPA, 20 x 23 x 40 in, with a 10 in exhaust collar and a dedicated 10 A, 115 V circuit. Alarm versions trip at 1.6 to 1.8 in of water column.

Skip it if your containments are large. At 1,000 CFM rated on high it suits small and mid-size containments; big ones want the 2,000 CFM class.

Widest airflow range: HEPACART HEPAFORCE AIR 2100

HEPACART rates the HEPAFORCE AIR 2100 from 50 to 1,700 CFM with a variable speed control, which lets you dial airflow down for a small room or up for a big one. The HEPA filter is listed at 99.99% at 0.3 micron and sits after the fan, and the prefilter is a MERV 8. HEPACART lists ICRA levels I to V for the HEPAFORCE AIR line, and the unit can hold negative or positive pressure.

It is 120 lb, 42 x 31 x 27.5 in, and draws 6 to 12 A on 120 V. See what ICRA is.

Skip it if you want a gauge and alarm on the panel, or if a flat 2,000 CFM rating at a lower price suits your jobs better.

Best compact stainless portable: Abatement PAS1200UV

The PAS1200UV is Abatement's upright portable with variable airflow from 300 CFM on low to 900 CFM on high, a certified metal-frame HEPA listed at 99.97% at 0.3 micron and a UV lamp. It adds an optional carbon prefilter stage. The cabinet is 20-gauge stainless steel, it weighs 85 lb and a GFCI duplex outlet lets you daisy-chain other units. It plugs into a 120 V, 15 A circuit, with a 400 W motor and a 3.5 A starting draw.

It stands 39 in tall on a 19.75 x 22 in footprint, against the H2KM's 35.75 x 26 in, and at 85 lb it is easier to roll from room to room.

Skip it if you do not need the UV lamp or stainless cabinet. The extra cost buys features, not airflow.

Best stackable: XPOWER X-3400A

The X-3400A is rated at 600 CFM on a 2.8 A draw and weighs 28.8 lb. It runs a washable nylon mesh first stage, a pleated media second stage and a HEPA50 third stage, with a filter change light and a variable speed control. A built-in GFCI outlet lets you daisy-chain machines, and XPOWER lists it as stackable up to five units. At 28.8 lb it is the lightest machine in this list, which suits bedrooms, closets and other small containments where a 120 lb cabinet is hard to carry in.

XPOWER's owner manual for the X-3000 series tells you to use the scrubber in an enclosed area with doors and windows closed, and says installing multiple scrubbers may be required for larger enclosed areas. The same manual warns against running it in high relative humidity, which it says can block and damage the filters, and says to plug it only into GFCI-protected receptacles. It also covers fitting a duct hose to the intake or exhaust. More XPOWER models sit in our XPOWER air scrubber range.

Skip it if you need a rigid 10 in or 12 in duct collar for a single large containment.

Best lower-priced pick: AlorAir PureAiro HEPA Pro 970

The HEPA Pro 970 is rated at 270 to 750 CFM with variable speed. AlorAir lists the filter as a combined HEPA and activated carbon stage with up to 99.95% of particles 0.3 micron and larger, behind a pre-filter and with a UV-C lamp. It is 39.6 lb, runs on 2.8 A at 115 V and has a 23 ft cord and an hour meter. The housing is rotomolded polyethylene.

The inlet is 16 in and the outlet is 8 in, and both can take duct, which is what makes it a negative air option for small containments. The panel has a 15 A GFCI outlet for chaining up to three units. Our AlorAir air scrubber range has the smaller siblings if you want a lower price still.

Skip it if your protocol or contract names a 99.97% filter, or if the containment is larger than a few rooms.

Best for large rooms: Abatement PAS5000

The PAS5000 is the biggest machine we carry in this group: Abatement lists up to 4,000 CFM, a 5 HP single-phase motor and 6 or more air changes per hour in containment areas up to 40,000 cubic feet. It needs 230 V at 30 A, so confirm the circuit before you order. Filtration is True HEPA at 99.97% at 0.3 micron with a 2 in pleated prefilter, and an optional Vapor-Lock granular carbon filter.

The control panel has speed control, indicator lamps, GFCI protection and an hour meter. The cabinet is 20-gauge galvanized steel on 5 x 2 in casters.

Skip it if the containments you work are houses and small commercial rooms. One or two 2,000 CFM machines such as the H2KM are the sensible size there.

How to choose by job

• Whole-house or basement containment: one or two 2,000 CFM machines (H2KM or 9103) ducted out. See basement mold remediation.
• Attics and crawl spaces: a light machine you can carry in, such as the HEPA Pro 970 or the X-3400A. See attic mold remediation and crawl space mold remediation.
• Healthcare or ICRA-controlled areas: a machine that lists ICRA levels, such as the HEPAFORCE AIR 2100, plus a pressure monitor.
• Large open floors: the PAS5000, or several 2,000 CFM machines.

For the rest of the kit, from moisture meter to containment, see the mold remediation equipment list and for what an air scrubber is in the first place, what is an air scrubber.

Price bands in our range

Frequently asked questions

Do air scrubbers help with mold?

Yes, during remediation. A HEPA air scrubber filters the air that passes through it, to the filter's listed rating, while the work disturbs dust and spores. It does not address growth on surfaces. Cleaning or removing the affected material and fixing the moisture source does that.

Is there an air purifier that fixes a mold problem?

No machine fixes mold growth. Find the moisture source and have the affected material dealt with.

What pulls mold out of the air?

Airborne particles are pulled through the filters by the fan. In a scrubber that is a prefilter and a HEPA stage, rated by the maker at 99.95% to 99.99% at 0.3 micron on the six machines here that list a figure. A carbon stage, where listed, handles odors, not particles.

Can I use a big-box store air purifier instead?

For a living space after the work, a household purifier can fit; our guide to air scrubber vs air purifier goes through the difference. For a containment, a household purifier lacks a duct collar, a high CFM rating and the build for job-site use. A ductable scrubber is the right tool there.

How many air changes per hour do I need?

Your protocol, contract or industrial hygienist sets the number, not us. To check a machine against a target, use ACH = CFM x 60 / room volume in cubic feet with the maker's rated CFM, then allow for lower real airflow through loaded filters.

How much does an air scrubber cost?

In our range, HEPA air scrubbers run from about $500 for small portables to over $6,000 for the 4,000 CFM PAS5000. Most ductable 2,000 CFM negative air machines sit between $1,000 and $2,000. Filters are a running cost on top, so price the HEPA and the prefilters before you buy.

Does a mold job require a HEPA air scrubber?

No single rule covers every job. The EPA's guide Mold Remediation in Schools and Commercial Buildings recommends limited containment for 10 to 100 square feet of mold and full containment above 100 square feet, with the area kept under negative pressure, which it says can be done with a HEPA-filtered fan unit exhausted outside the building. Your protocol, contract and local rules decide the rest; our equipment list covers the full kit.

Related guides

• Mold Remediation Equipment: The Full Kit by Job Size, From Moisture Meter to Negative Air
• Air Scrubber vs Negative Air Machine: Same Box, Different Setup (and When You Need Each)
• What Is an Air Scrubber? How a HEPA Air Scrubber Works and When You Need One
• Air Scrubber vs Air Purifier: Airflow, Filters and Which One a Job Needs