The Dri-Eaz HEPA 500 Primary HEPA Filter (F321) is the essential high-efficiency filtration component designed for use with the Dri-Eaz HEPA 500 Air Scrubber. This true HEPA filter captures 99.97% of particles down to 0.3 microns, for clean air during restoration, remediation and construction applications.
Important: For Existing HEPA 500 Machines
Legend Brands (Dri-Eaz) has discontinued the DefendAir HEPA 500 air scrubber but continues to supply its filters for existing machines. This filter is for owners of a HEPA 500 already in service. If you are buying a new air scrubber, see our Air Scrubbers range.
Features
- Proper HEPA filtration — removes fine particulates including dust, mould spores, pollen, pet dander and other airborne contaminants.
- Made for the HEPA 500 — manufactured for the Dri-Eaz DefendAir HEPA 500 to suit its airflow and filter housing.
- High dust-holding capacity — helps reduce filter changes during extended restoration jobs when the pre-filters are kept in place (see the chart below).
- Rugged, commercial-grade construction — built for demanding environments such as water damage restoration, construction sites and mould remediation projects.
Applications
- Water and flood restoration
- Mould remediation and IAQ (Indoor Air Quality) control
- Construction dust control
- Odour removal when paired with activated carbon filters
- Commercial and residential air scrubbing
Protect the HEPA with Pre-Filters
The HEPA filter is the most expensive filter in the machine and the last line of defence. Let the cheap filters in front of it take the bulk of the load. Running a HEPA 500 without a pre-filter on a dusty site loads the HEPA quickly and cuts airflow. Use the chart below to set the machine up for the job.
Specifications
| Brand | Dri-Eaz (Legend Brands) |
| Product code | F321 (Dri-Eaz part number 111192) |
| Filter type | True HEPA — 99.97% @ 0.3 microns |
| Compatibility | Dri-Eaz DefendAir / HEPA 500 Air Scrubber |
| Position in the machine | Final filter, behind the pre-filter stages |
| Dimensions | 405 × 482 × 55 mm (CCW measurement — the filter is flared, so it has different dimensions on each side). See the note below. |
| Installation | Simple drop-in replacement |
| Sold as | Each (Dri-Eaz packs the F321 in eights in the US) |
Size note: US distributors list the F321 as 16 × 19 × 2.5 in (about 406 × 483 × 64 mm), and one lists it as 16 × 19 × 2 in. Width and height agree with CCW's measurement; the depth does not (55 mm vs 51–64 mm). The flared frame is the likely reason. Dri-Eaz does not publish the dimensions. If your filter housing is not a HEPA 500, measure the filter you are replacing and send us the figures before ordering.
Choosing Your Filter Configuration
The DefendAir HEPA 500 can be configured with a variety of filters to suit your specific air scrubbing requirements. Use the chart below to find the best filtering configuration for the job at hand.
| Filtering application | First filter position | Second filter position | Final filter (HEPA) |
|---|---|---|---|
| Clean water loss air scrubbing. For a relatively clean environment. | (no filter necessary) | 2nd Stage Pre-Filter (F271 or AC36F2) | HEPA filter (F321) |
| Standard air scrubbing. For environments with higher particle loads, such as construction or remodelling sites. | 1st Stage Pre-Filter (F270) | 2nd Stage Pre-Filter (F271 or AC36F2) | HEPA filter (F321) |
| Odour control and air filtration. For the removal of volatile organic compounds (VOCs), food odours, fumes from paint and paint thinners, sewer odours, and many other noxious odours. | Activated Carbon Filter (F397) | 2nd Stage Pre-Filter (F271 or AC36F2) | HEPA filter (F321) |
Filter Types
- 1st Stage Pre-Filter (F270). Synthetic fibre filter media rated at 10% efficiency. Captures the largest particles to help extend the life of the higher efficiency filters inside. More info.
- 2nd Stage Pre-Filter (F271 or AC36F2). Synthetic fibre filter media rated at 30% efficiency. Captures larger particles to help extend the life of the HEPA filter. More info. AC36F2 is CCW's aftermarket pre-filter — check its size against your machine before ordering.
- Activated Carbon Filter (F397). The activated carbon filter removes a wide variety of compounds, including volatile organic compounds (VOCs), food odours, fumes from paint and paint thinners, sewer odours, and many other noxious odours. Combining activated carbon filtration with HEPA filtration is especially effective in removing airborne soot particles and the odours they create. More info.
- HEPA filter (F321). The HEPA filter has an efficiency rating of 99.97% against 0.3-micron oily aerosol particles. The HEPA filtration standard was developed in the 1940s to control radioactive dust particles in U.S. nuclear laboratories. More info.
Changing the HEPA Filter
- Switch off and unplug the machine before opening the cabinet.
- Wear the PPE the job calls for — a used HEPA filter holds everything the machine has captured, including mould spores and fine dust.
- Check the new filter's frame and seal for damage before fitting. A HEPA filter that does not seal lets air bypass the media, and the machine is no longer HEPA filtering.
- Bag the old filter on site before carrying it through the building.
- Dri-Eaz's guidance: HEPA 500 filters are designed to be replaced after use to prevent cross-contamination. Do not clean and reuse them.
Frequently Asked Questions
What does 99.97% at 0.3 microns mean?
It is the HEPA efficiency rating: the filter captures at least 99.97% of particles at 0.3 microns, the size that is hardest for filter media to catch. Larger and smaller particles are captured at a higher rate.
Can I vacuum or wash the HEPA filter and reuse it?
No. Cleaning damages the media and releases what it has captured. Dri-Eaz says to replace HEPA 500 filters after use and not to clean and reuse them.
Do I need pre-filters as well?
Yes, for anything other than a relatively clean water loss. The 1st stage (F270) and 2nd stage (F271) pre-filters take the coarse load and extend the life of the HEPA filter.
Will it remove odours?
Not on its own. HEPA filters capture particles, not gases. For smoke, sewage and VOC odours, add the activated carbon filter (F397) in the first position.
Is the HEPA 500 still made?
No. Legend Brands has discontinued the machine but still supplies its filters for existing units.
Related Products
- Dri-Eaz HEPA 500 Carbon Pre-Filter (F397)
- Dri-Eaz HEPA 500 1st Stage Pre-Filter (F270)
- Dri-Eaz HEPA 500 2nd Stage Pre-Filter (F271)
- Aftermarket Pre-Filter for HEPA 500 & XPower X-3400 (AC36F2)
- Filters & Filter Bags
- Air Scrubbers
Not sure the F321 is the right HEPA filter for your machine? Send us the machine model or the size of the filter you are taking out and we will confirm before you order.
