Austin Air Allergy Machine HEPA/HEGA Air Purifier - HM405


The Austin Air Allergy Machine helps those with allergies or asthma looking for optimized removal of particulates and gaseous pollutants, including VOCs. Built with over 60 sq ft of True HEPA filter media, the Allergy Machine also incorporates an advanced military-grade HEGA carbon cloth to absorb a high level of smoke, odors, gases, fumes, and other VOCs. Significantly improves air quality in medium to large-size rooms, and is recommended in households with heavy smoke or VOCs.  Long-life HEPA saves on filter replacements.

MSRP $794.00 Selling Price $634.99
In stock

This product provides relief from: Asthma, Bacteria & Germs, Dust Allergies, Dust Mites, Fragrances & Odors, Mold & Mildew, Pet Dander, Pollen

See a brief video showing Austin Air HEGA Filtration:

The Austin Air Allergy Machine HEPA/HEGA Air Purifier (HM405) helps those combating allergy and asthma-related problems who are also exposed to higher levels of smoke, cooking odors, chemical vapors or VOCs that can trigger or worsen symptoms. The Allergy Machine uses True Medical-Grade HEPA for extreme particle filtration, plus an advanced military-grade carbon cloth for high-efficiency HEGA filtration of gases, odors and VOCs. Customers using the Allergy Machine often remark on the abundant quantity of clean air it produces, and how they can really "feel" the difference in better breathing, reduced symptoms, and less waking up at night. Like all Austin Airs, this no-nonsense machine is simple (no electronic extras), yet very effective at doing what it's designed to do best – remove copious amounts of particulate matter, gaseous odors, chemical vapors, and harmful VOCs from indoor air.

Austin Air was founded in 1990 in Buffalo, New York by a husband trying to help his wife find relief from lifelong asthma symptoms, which he did with the Austin Air HealthMate. Today, Austin Air continues to operate out of Buffalo, and husband (now president) Richard Taylor and crew continue to build air purifiers with a "family first" mentality, knowing that cleaner air can benefit all those affected by respiratory issues.

Which Austin Air Purifier is right for me? Click here to view comparison chart.

Why Austin Air?

  • Superior Filtration ‐ Particles, Gases, Odors and VOCs

    Most Austin Airs, including the Allergy Machine, provide 4 stages of intense filtration (5 stages with the Bedroom Machine). What makes the Allergy Machine unique is its filters and filtration process. Two pre-filters begin by removing larger particles – one wrapped around the interior of the unit's housing, the other surrounding the HEPA filter. Next, comes 60 square feet of True Medical-Grade HEPA filter media (to trap sub-micron particles). Following the HEPA is an advanced military-grade HEGA carbon cloth filter (to trap odors, gases and VOCs).

    Unlike typical carbon filters (which sit before the HEPA), Austin's advanced HEGA carbon cloth releases no carbon dust when air passes through it, so can be placed after the HEPA. This sequence means air passes through the HEPA before passing through the HEGA carbon filter, leaving the total surface area of the carbon filter available solely for gas, odor and VOC removal. This design not only maximizes the performance of each filter, but also increases the usable life of the HEGA carbon filter and decreases the weight of the filter assembly from 21 lbs to 8 lbs.

    No other air cleaner in its class can match the performance of the Allergy Machine. It simply "out filters" other brands. Austin Air backs this up by providing a 5-Year Pro-Rated Filter Warranty, in addition to its 5-Year Mechanical Warranty.

  • Designed for Performance

    Austin Air machines process 250 cubic feet of air every minute (125 cubic feet for the junior models). Air is drawn in from all sides of the unit via its 360° air intake grilles, where it immediately begins to be pulled through Austin's 4-stage or 5-stage filter, which progressively removes dust, hair, fibers, odors, gases, VOCs, Radon daughters, pollen, pet dander, mold spores, bacteria, viruses, and other allergens and contaminants.

    Austin Airs feature high-velocity airflow (75-400 cfm for standard-size units, 50-200 cfm for junior sizes), which helps to quickly create a pocket of clean air around the user. Run on high with the door closed, and assuming four air changes per hour, Austin Airs can clean a 465 sq ft room in 15-20 minutes (or a 480 sq ft room in 30-40 minutes for junior sizes).

    Austin Airs produce 50-66 dBA (decibels) of noise, depending on fan speed selected. Customers report it to be very quiet on the low setting. Set at high, the sound approximates that of a normal conversation. Many customers use the high setting for quick or maximum air cleaning.

    Austin Airs are solidly made. Each unit is built using 22-gauge welded steel that does not rattle or vibrate, even at max speed. A powder-coated finish (baked at 375°F) does not off-gas and lends durability. Standard-size models come equipped with heavy-duty casters for easy portability. Casters are optionally available for Junior-size models.

    Austin Airs save energy. Energy efficient PSC motors, equipped with a centrifugal fan, use less energy than some light bulbs. Electricity to run a standard-size unit at max draw (132 watts) should cost about 1.5 cents an hour, and about 1 cent an hour to run a junior-size unit at max draw (82 watts), based on average residential electricity rates projected by the United States EIA for 2014-2015. Energy costs for each size will be less when run on the lower fan speeds.

  • Made in USA

    Austin Air produces everything here in the USA out of its 480,000 square-foot facility in Buffalo, New York – the largest air cleaner manufacturing facility in the world. While made on American soil, Austin Airs can be found helping people in homes throughout the world. Austin Airs are also used in hospitals and clinics, and have even been called to national service by the U.S. Army Corps of Engineers, and to assist FEMA and the Red Cross in the aftermath of 9/11. When clean air is crucial, and lives depend on it, Austin Air remains the #1 choice.

  • Integrity in Claims about the Product and Test Results

    Austin Air believes in being straight with consumers about what its products can and cannot do. The company does not use private testing, but rather each air purifier undergoes tough government and third-party testing, whose stringent standards must be met to ensure products perform as claimed. For example, wide-ranging product tests conducted by Battelle Laboratories (a well-respected testing laboratory for the Army Corps Engineers at the U.S. Army Aberdeen Test Center) have included flow design and rate, as well as gas, odor and sub-micron particle removal.

  • Ease of Use and Low Maintenance

    Austin Airs come ready to be plugged in. Each unit comes with two filters ‐ the outer pre-filter, and the HEPA filter assembly. All models use a manual rotary dial to switch between 3 fan speeds ‐ High (III), Medium (II) and Low (I). Austin Airs can be placed anywhere in a room, but should be at least 4-8 inches from a wall for maximum effectiveness.

    Austin Air filters are designed to last five years, which saves on the hassle and cost of frequent filter replacements. If filters do need to be replaced, the process is straightforward and should take only a few minutes. Although the bottom cover must be removed using a Phillips-head screwdriver (4 screws), filters just lift out for easy replacement. The outer surface of the units need only be vacuumed monthly to remove dust particles that may accumulate on the exterior air intake grilles.

The Allergy Machine provides clean air in rooms up to a maximum of:

  • 1500 sq. ft. (1 air change per hour)
  • 875 sq. ft. (2 air changes per hour)
  • 600 sq. ft. (3 air changes per hour)
  • 465 sq. ft. (4 air changes per hour)
  • 375 sq. ft. (5 air changes per hour)
  • 315 sq. ft. (6 air changes per hour)

Austin Air Allergy Machine (HM405) Features:

  • HEPA filtration helps reduce exposure to particulates that cause allergic reaction or respiratory distress
  • HEGA filtration, using advanced military-grade carbon cloth, reduces odors, gases, fumes, chemical vapors, and VOCs
  • Unmatched 4-Stage Filtration Power:
    • Stage 1:  Large Particle Permafilt™ Pre-Filter removes dust, hair, and pet dander
    • Stage 2:  Medium Particle Pre-Filter removes pollen, molds, and other spores
    • Stage 4:  True Medical-Grade HEPA (60 sq ft) removes allergens, bacteria, viruses, and other particulates:
      • 99.97% removal of particles larger than 0.3 microns
      • 95.0% removal of particles larger than 0.1 micron
    • Stage 4:  Military-Grade HEGA Carbon Cloth removes more gases, odors and chemical contaminants
  • Powerful 360° air intake system maximizes efficiency and speeds delivery of filtered air
  • Air outlet at upper-side can be directed where you need it most
  • Energy efficient PSC motor, rated for continuous use at high RPM
  • Low cost of ownership ‐ no filter changes for up to 5 years
  • 3-speed rotary dial  (low, medium, high)
  • Solid steel construction
  • Heavy-duty, easy-roll casters
  • 23"H x 14.5"W x 14.5"D ‐ 35 lbs
  • Baked-on powder coat does not off-gas
  • Available in 5 colors
  • Ozone free
  • Made in USA
  • Manufacturer's Warranty:
    • 5-Years Mechanical on Air Cleaner
    • 5-Years Pro-Rated on Filter

International Orders:  Austin Air purifiers are available with electrical plugs for international voltage. Please call 1-800-522-1448 for information, pricing, and shipping charges on units to be used outside of North America.

More Information

If you have asthma or suffer from bouts with allergies, the Allergy Machine could be your ticket to freedom. Austin Air designed this machine especially for you. It provides exceptional HEPA performance for particle removal, and its advanced military-grade HEGA carbon cloth easily cleans air of heavy gaseous pollutants, like tobacco smoke, odors, vapors and fumes. Customers overwhelmingly give the Allergy Machine "two thumbs up."

Room Size

up to 1500 sq. ft.

Recommended For

Allergies, asthma, heavier odors, smoke, gases, chemicals, and VOCs

Best Fit

Best choice for allergy and asthma sufferers wanting optimum removal of respiratory irritants

True HEPA Filtration


Particle Filtration Efficiency

99.97% to 0.3 microns
99.5% to 0.1 micron

Particle Removal

Dust, dust mite allergen, pollen, pet dander, mold spores, bacteria, viruses

Gas and Odor Removal

Tobacco smoke, wood smoke, chemical vapors, radon daughters, formaldehyde

VOC Removal


Optional Filters


Unique Features / Benefits

Filters last up to 5 years. HEPA and HEGA filtration maximizes capture of particles, microbes and gaseous pollutants. Low maintenance. Made in USA.

CADR: Dust rating

Not tested by AHAM

CADR: Pollen rating

Not tested by AHAM

CADR: Smoke rating

Not tested by AHAM

ACH (air changes per hour)

ACH per room size:
• 1 ACH ‐ 1500 sq. ft.
• 2 ACH ‐ 875 sq. ft.
• 4 ACH ‐ 465 sq. ft.
• 6 ACH ‐ 315 sq. ft.

Airflow (cubic feet per minute)

75-400 cfm

Filtration System

4-stage filtration:
• Permafilt™ pre-filter
• Cotton/poly pre-filter
• 60 sq. ft. True HEPA filter
• Military-grade HEGA carbon cloth

Number of Filters to Replace

1 filter pack (includes all filters)
Note: Outer pre-filter can be replaced separately, if needed

Replace HEPA Filter

5 years ‐ HEPA filter pack (normal use)

Replace Pre-Filter

See above ‐ part of HEPA filter pack

Replace Other Filters

See above ‐ part of HEPA filter pack

Dimensions (H x W x D)

23" x 14.5" x 14.5"

Color choices

Black, White, Silver, Sandstone, Midnight Blue

Product Weight

35 lbs

Packaged Weight

39 lbs

Shipping Weight

51 lbs

Noise Level - (min-max decibels)

<50-66 dB(A)


Manual ‐ rotary dial

Remote Control


Number of Fan Speeds


LCD Display




Programmable Cycles or Timer


Sleep Mode


Auto Fan Mode (auto adjusts based on air quality)


Particle, Gas or VOC Detector


Filter Status Indicator


Filter Reset function


Other Indicators


Other Features


Casters or Handles


Air Inlet

360° ‐ all sides

Air Outlet

Upper deck ‐ right side

Housing Construction

22-gauge steel. Baked-on powder coat paint finish.

Fan / Motor Assembly

Plastic centrifugal fan. 3-speed control. Long-duty PSC motor, rated for continuous high RPM.

Energy Consumption (watts)

56 to 132 W

Power Requirements

120 V, 60 Hz

Power Plug

Power cord approx. 5-6-feet, 2-prong polarized plug


1.1 Amps

Energy Star®


AHAM-certified CADR


Approvals / Other Certifications

CSA, NRTL, CE approved. California ARB certified.

Ozone Emission


Manufacturer's Warranty

• 5 Years Mechanical
• 5 Years Pro-Rated Filter

Austin Air Allergy Machine Instructions

Please see Owner's Manual tab for setup and operating instructions, plus full instructions on changing the filters. A one-page set of instructions on filter changes is also provided.

General on Pre-Filter:

  • The outer Stage 1 pre-filter (which you can see can through the unit's perforated grille) can last for years with regular cleaning. Just vacuum the outer surface of the unit monthly (you do not need to open the unit) by using the brush attachment of your vacuum to remove dust from the outside of the unit and large particles from the pre-filter.

  • If you do not maintain the outer Stage 1 pre-filter or if it becomes damaged, genuine Austin Air replacement filters are available through National Allergy.

General on HEPA Filter:

  • Austin Air filters are designed to last up to 5 years. However, please remember that the filter's service life is related to the volume of air that passes through the air purifier and the amount of contaminants in the air. If your indoor air has an unusually high level of airborne particulates, smoke or gaseous contaminants, the filter's service life may be shortened.

  • Regular maintenance helps to prolong the life of the HEPA filter. Keep the area surrounding the air purifier clean, and be sure to vacuum any dust buildup on the outside of the unit, especially on the 360° air intake grille.

  • Replace the HEPA filter pack if you notice a significant drop in clean, odorless air flow.

  • Important ‐ For first-time use or any time you change the HEPA filter pack, it is important that you run the purifier on the High (III) setting for at least the first hour of use. After the first hour, turn the Speed Control Setting to the desired level.

Click here to view the Austin Air Owner's Manual.

Click here for a one-page set of instructions on filter changes for the Austin Air.

Signature Is Required For Delivery

Sorry, Austin Air units cannot be shipped to PO boxes or military addresses.
Usually Ships in 1-2 Business Days Direct from the Manufacturer.