Air Scrubbers for Construction Dust and Drywall Sanding: Sizing and Picks

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.

For drywall sanding or demo in one room, run a HEPA air scrubber of about 500 to 750 CFM inside the work area with its exhaust ducted out of the room. That sets up negative air and cleans up the fine dust that escapes at the sander.

Our one-room pick is the Abatement Technologies PAS750 at $1,139. The AlorAir PureAiro HEPA Max 870 at $699 is the budget pick. Suites and open floors need 1,000 to 2,000 CFM or several units, which is where the KwiKool BioAir 1800 and the PAS2400 come in.

Why construction dust changes the choice

Drywall sanding, demolition and cutting make a lot of very fine dust in a short time, and it settles on everything you just finished. Three things set the machine you need: how big the work space is, how fast the pre-filters clog, and how many amps the jobsite circuit has left. A scrubber built for a quiet restoration job can still do this work, but you will change filters far more often.

The plan has more parts than one machine. Sealing the room, capturing dust at the tool and a HEPA vacuum for cleanup all matter, and our dust control in construction guide walks through that whole sequence. This post covers only the air scrubber: size, pick, filters and power. If you are new to the machine itself, start with what an air scrubber is.

Sizing by job: one room, a suite or an open floor

The formula is the one in our air changes per hour guide: CFM needed = room volume in cubic feet x ACH / 60. For the target, Abatement Technologies' PREDATOR manual says that for jobs with no ACH figure given, most users aim for at least 6 ACH on construction areas. It also advises building in a safety factor to cover filter loading, duct losses and reduced voltage, and gives 7.5 ACH as the figure for a 25 percent safety factor on a 6 ACH goal.

This is our calculation from the formula, using each maker's rated CFM; real jobs have openings, furniture and long duct runs. The open-floor row shows why big floors are often split into zones with plastic barriers: it is easier to run four small rooms than one 60,000 cubic foot space.

Rated CFM is not delivered CFM

Check KwiKool's own claim with the formula. It lists about 2,000 sq ft at 6 ACH with a 9 ft ceiling, which is 18,000 cubic feet. At 1,800 CFM that works out to 6 ACH, but at the 1,600 CFM it lists with one opening closed it is about 5.3 ACH (our calculation). Abatement's PREDATOR manual says system airflow drops with filter loading, a blocked inlet or too much flex duct, and it advises keeping ducting as short as possible with the fewest bends. Rigid metal duct creates less turbulence than flexible duct, and flex duct should be kept taut.

How we picked

We did not test these machines. The picks come from our catalog data, the makers' spec sheets and manuals, and the price bands in our range. None of the seven has owner reviews on our product pages yet, so there are no owner quotes below and we do not guess at how any of them holds up. We chose the seven to cover one-room work, mid-size jobs and large floors at three price tiers.

Best for one room: Abatement Technologies PAS750

The PAS750 lists variable airflow up to 750 CFM, a HEPA filter certified to 99.97% efficiency at 0.3 microns as Abatement rates it, and an amperage draw of 1.9 amps or less. It weighs 33.5 lb, runs at 62 to 67 dBA and has a 10 inch exhaust outlet for ducting out of the room. Its pre-filters are a 1 inch Fiber-Trapper coarse filter and a 2 inch pleated filter, two stages that take the first hit from drywall dust. It stacks up to three units and is among our best-selling air scrubbers.

Skip it if the floor is bigger than a large room and you do not want to run several units. Abatement also makes the PREDATOR PRED750 at $1,070: 200 to 750 CFM, 1.9 A or less and 35 lb in a polyethylene cabinet, which Abatement rates for 6 ACH in up to 7,500 cubic feet. Abatement's quick start video below walks through setting up a PREDATOR 750, not the PAS750.

Best value for small rooms: AlorAir PureAiro HEPA Max 870

At $699 it is the entry point of this group. AlorAir lists 270 to 550 CFM with variable speed, a combined HEPA and activated carbon filter rated up to 99.95% of particles 0.3 micron and larger, and a 2.5 A draw. The inlet is 14 inches and the outlet 8 inches, both ductable, and the static pressure row reads 2.8 inches of water. It has a 23 ft cord, a GFCI duplex outlet that lets up to three units chain together, an hour meter and a rotomolded polyethylene housing. It also carries a UV-C lamp, which does nothing for dust control.

Do not read 99.97% into its filter rating; AlorAir's figure is 99.95%. AlorAir backs it with a 12-month limited warranty on defects in materials and workmanship.

Skip it if you need more than 550 CFM from one machine. AlorAir lists coverage of up to 800 sq ft. With an 8 ft ceiling that is 6,400 cubic feet, about 5.2 ACH at 550 CFM (our calculation), so treat 800 sq ft as the top end for sanding.

Best low-amp mid pick: XPOWER AP-1500D

XPOWER rates the AP-1500D at 700 CFM and lists a 1.5 A draw, the lowest in this group, from a DC brushless motor with variable speed and a 13 ft cord. It has a built-in PM2.5 sensor that shows a particle reading, which is useful as a visual check on how dusty the room is but is not a health measure. It weighs 45.9 lb, stacks up to two units and takes 12 inch duct. The housing is roto-molded polyethylene and it carries ETL/CETL safety marks.

XPOWER's listing gives no HEPA efficiency figure. Skip it if you need a rated efficiency on paper, or if your duct kit is 10 inch: it takes 12 inch duct.

Best two-speed pick with a filter gauge: Aerospace America Aeroclean 600 MAG 9145

The 9145 is rated at 625 CFM on high and 425 CFM on low, with a 1 HP two-speed motor, a pressure gauge and a push-button circuit breaker. At 9.0 amps it is the heaviest draw of the single-cord picks, and at 80 lb it is heavy. Its filters are a 16 x 16 x 1/2 inch pre-filter, a 16 x 16 x 1 inch secondary and a 16 x 16 x 6 inch HEPA. The standard 9145 is $1,019.20; the 9145FF Full Feature adds a red high-pressure warning light with an audio alarm at $1,174.60.

Skip it if you will share a 15 amp circuit with other tools. See the amps section below.

Best variable-speed workhorse: Novatek Novair 1000

The variable-speed Novair 1000 gives you a dial from 100 to 1,000 CFM with all filters installed, a 1 hp motor and a 115 V, 5 A rating. The HEPA is a 16 x 16 inch metal mini-pleat (Novatek part F4032) behind a two-ply ring filter and a pleated carbon filter. The configurations are priced apart: HEPA at $1,195, HEPA with alarm and light at $1,375 and HEPA with alarm, light and hour meter at $1,425. It weighs 94 lb and has a 10 inch exhaust collar.

The manual describes a differential pressure gauge that reads about 1.0 to 1.2 inches of water column with new filters and about 1.6 to 1.8 inches when they are loaded; the alarm configurations trip at that 1.6 to 1.8 point. That is a handy way to know when drywall dust has loaded the filters. The manual also calls for a dedicated 10 amp circuit.

Skip it if you need to lift it into a truck alone.

Best for a suite: KwiKool BioAir 1800

KwiKool lists 1,800, 1,675 and 1,550 CFM at zero static on three speeds, and 1,600, 1,375 and 1,250 CFM with one opening closed. It uses a 4 inch HEPA rated 99.97% at 0.3 micron, draws 7.2 A on the Plus (7.3 A on the Max) and weighs 135 lb, with a 12 inch stainless top flange. Its cord is 6 ft with a NEMA 5-15 plug, so plan the outlet or a rated extension cord. The BioAir Plus KBP1800 is $2,726.50 and the Max KBX1800, which adds ionization, is $3,286.50. Both carry UVC lamps, which we do not count as dust control.

Skip it if the work is one room; a 135 lb machine is more than it needs.

Best for large floors: Abatement Technologies PAS2400

The PAS2400 lists 2,100 CFM on high and 700 on low, a static lift of 5.5 inches, and a True HEPA rated 99.97% at 0.3 micron. It runs on 120 V and 15 A, with a stainless cabinet, a built-in dolly with a stair climber, GFCI protection and an hour meter. Its pre-filters are a 1 inch Fiber-Trapper and a 2 inch pleated filter. It has sold on our store, though not as often as the PAS750.

Skip it if the job is one or two rooms: 2,100 CFM on high and a dolly-mounted stainless cabinet are built for open floors.

Amps on a shared jobsite circuit

Sanders, lights and vacuums share the same breakers, so add the scrubber's draw to the rest. The table is our calculation from the amps rows, on a 15 amp circuit.

On a crowded floor, a 750 CFM unit that draws 1.9 A leaves a lot more of the circuit for the sander than a unit that draws 9.0 A.

Replacement filter prices

Drywall dust loads pre-filters quickly, so budget for filters as a job cost, not a surprise. Change them by the gauge or the maker's manual, not by the calendar. Abatement's PREDATOR manual lists pre-filter loading among the causes of reduced airflow, and Novatek's manual says to check filters daily and replace them if needed. Below are the replacement parts we carry, priced by variant.

See the parts pages for the Novair 1000 HEPA filters, the BioAir 1800 replacement filters and the Aeroclean 16 x 16 inch filters. HEPA filters are replaced, not washed; our HEPA filter replacement guide explains why. A case of 40 pre-filter pads costs far less per job than a HEPA, which is a reason to change pre-filters often.

Price tiers

What OSHA says about silica dust

Cutting or demolishing concrete, brick, block or stone throws off silica, and OSHA covers that under 29 CFR 1926.1153, its respirable crystalline silica standard for construction. The standard sets the permissible exposure limit at 50 micrograms per cubic meter of air over an 8-hour shift and lets an employer either use the controls in Table 1 or measure exposure and pick its own. Table 1's controls work at the tool, such as water delivery and shrouds connected to a dust collector, and it does not list room air scrubbers, so a scrubber adds to those controls rather than replacing them. No machine here is claimed to meet it: read the standard and ask the maker. Our dust control guide gives the silica rule its own section, and for drywall sanding, check the joint compound's safety data sheet for what it contains.

Setup tips for a dusty job

• Seal doors and returns first; see how to set up a negative air machine and what a negative pressure room is.
• Put the scrubber inside the work area, with the exhaust ducted out through a window or door.
• Keep ducts short and straight, as Abatement's PREDATOR manual advises.
• Do not use a box fan in place of a rated HEPA machine; our box fan versus HEPA air scrubber comparison explains the difference.
• Read the gauge or check the pre-filters daily on a sanding job.

Frequently asked questions

Do air scrubbers work for construction dust?

Yes, when sized and ducted properly. An air scrubber filters the air it draws in, and the HEPA stage is rated as the maker states, for example 99.97% at 0.3 micron on the PAS750. It does not replace sealing the room or capturing dust at the tool.

How do I get rid of construction dust in the air?

Seal the work area, capture dust at the tool and run a HEPA air scrubber, then HEPA vacuum the surfaces. Our dust control in construction guide lays out the order.

Is there a machine that can remove dust from the air?

Yes, a HEPA air scrubber filters airborne particles as rated. How much it handles depends on its real airflow, the filter condition and the room volume.

Will an air purifier help with mold and dust?

An air scrubber filters air, but mold is removed by remediation, not by a machine. Our air scrubber versus air purifier guide covers what each machine does.

How do I clean the dust out of an air purifier?

Change the pre-filters when they load; HEPA filters are replaced, not washed. See how often to change a HEPA filter.

How many CFM do I need for drywall sanding?

Take room volume x 6 ACH / 60, then add a safety factor. A 5,400 cubic foot room works out to 540 CFM at 6 ACH and 675 CFM at 7.5 ACH (our calculation).

Related guides

• Dust Control in Construction: Seal, Run Negative Air and HEPA Vacuum
• Air Changes per Hour Formula: How to Calculate ACH and Size an Air Scrubber
• DIY Box Fan Air Scrubber vs a HEPA Air Scrubber: What a Box Fan Can and Cannot Do
• How to Set Up a Negative Air Machine and Create Negative Pressure in a Room