Diffuser Filtration for Commercial Stainless Steel HVAC Products from AJ Manufacturing

Many of our stainless steel diffusers are available with options including HEPA and ULPA filters.

These high-quality, effective filters are commonly used in hospitals, semiconductor manufacturing, disk drive and compact disc manufacturing, pharmaceutical production, and aerospace manufacturing.

Specifications & Details


Filter Installation Instructions

HVAC Diffusers with Filter Options

  • Stainless steel laminar flow diffusers
  • Radial flow diffusers
  • Flat radial diffusers
  • Non-hinged or hinged radial diffusers
  • Plenum models
  • Combination grilles
  • Plaster frame models

Contact us to get an estimate or place an order.

Our Stainless Steel Air Filter Standards

Standard filters from AJ Manufacturing incorporate an anodized aluminum gel seal frame to provide a leak-tight connection and a separatorless deep media pack as a standard.

Test ports on filters are optional, upon request. The test port measures filter pressure drop, performs leakage tests, and adjusts balancing dampers in the diffuser neck.

All our filters are UL 900 Class I Listed and Factory Mutual Approved. All filters under scan tests per Section 6.2 of IEST-RP-CC034.1 and are packaged independently from the diffuser for final installation in the field. ULPA filters are assembled and tested in a cleanroom environment before being sealed in a poly bag.

How We Test Our Air Filters

All filtration testing is completed using aerosol constructed of man-made spheres, not with authentic biological or irregularly-shaped particles.

This method provides a repeatable test to ensure manufacturing quality. Depending on your diffuser application and conditions in your environment, actual efficiency may be lower.

Testing is performed at 100 fpm (0.51 m/s) velocity on the net media surface area. During these tests, our filters have been shown to maintain their ratings at up to 150 fpm (0.76 m/s) velocity.

Filtration Rates

HEPA filters have a 99.99% minimum removal efficiency on 0.3 micrometer particle sizes, while ULPA filters have a 99.995% minimum removal efficiency on 0.12 micrometer particle sizes.

The filtration efficiency of filters follows a specific nonlinear curve. Filters are classified by the efficiency at a particular particle diameter, and generally a smaller particle will have a slightly lower filtration efficiency. Many pathogens responsible for nosocomial infections have particles in a size range of fewer than 0.2 micrometers, but are attached to larger particles found in clumps, which will break apart upon contact with filter fibers.

Filtration experts recommend that actual particle size be used to determine a conservative filtration efficiency requirement.

Clean air is critical.

Select your air filtration option when you order our stainless steel HVAC diffusers for your project.

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