Original Criti-Clean FFU

Diffusers for Critical Environments from AJ Manufacturing

Our original laminar flow diffuser for critical environments started it all. It was the industry’s first high-performance, intelligent fan filter unit with stainless steel construction and an all-welded plenum. The original Criti-Clean Fan Powered Laminar Flow continually delivers a non-aspirating, low-velocity, uniformly-distributed, downward-moving piston of HEPA-filtered air.

Today, it remains in use in a variety of critical environments, including hospital operating rooms. Our original has a slightly lower maximum output and larger plenum height than the upgraded Criti-Clean Ultra. However, it remains an invaluable component to your critical environment air distribution system.

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Standard Features of the Original Laminar Flow Diffuser

The original Criti-Clean, item SSLFHFD-FP, comes standard with the following:

  • Type 304 Stainless Steel
  • All-welded
  • Forward-curved EC motor
  • Removable faceplate for cleaning, secured by quarter-turn fasteners
  • Digitally-controlled ECM motor that provides constant airflow for even air distribution and field balancing
  • Digital controller displays airflow (CFM)
  • Cleanable, expanded aluminum prefilter
  • 2” HEPA filters
  • Safety cables to prevent accidental dropping of removable face
  • Perforated face with 3/16” diameter holes on 60-degree ¼” staggered centers
  • 51% free area
  • Round duct inlets for simple duct connection
  • Integral earthquake hanger tabs
  • Compatibility with lay-in T-bar ceiling systems and surface-mount applications
  • Clear anodized aluminum filter frame with test port for filter pressure drop measurement or leakage (scan) tests
  • Independently-packaged filters ready for final installation in the field
  • #4 satin polished finish 
  • Three size options

Optional Upgrades

Talk to your sales adviser to learn more about these upgrades:

  • Type 316 stainless steel
  • Rectangular or oval duct openings
  • HEPA filter (99.99% on 0.3 micrometers) in sizes other than 2”
  • ULPA filter (99.9995% on 0.12 micrometers)
  • LED indicator light to alert user to change filter
  • PAO challenge and static port
  • UV-C germicidal irradiation
  • Baked-on epoxy-polyester hybrid powder coat finish
  • Built-in LED lights (eliminates need for additional light fixtures)

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Original Criti-Clean FFU Sizes

24”x24” Unit

Performance Data
IES Photometric File for LED Lighted Unit

36”x24” Unit

Performance Data
IES Photometric File for LED Lighted Unit

48”x24” Unit

Performance Data
IES Photometric File for LED Lighted Unit

Fan Filter Unit Specifications

AJ Manufacturing makes available detailed submittals and instructions for your planning needs. Contact us for additional information specific to your project by calling 816-231-5522 or sending an email.

SSLFHFD FP STD (Standard Build) Submittal
SSLFHFD FP MEA (Motor & Electronics Accessible) Submittal
SSLFHFD FP MEA LED (Motor & Electronics Accessible with LED Lighting) Submittal
SSLFHFD-FP-MA (Motor Accessible) Submittal

Installation Instructions

Controlling Air Distribution

For recommendations on controls options, contact AJ Manufacturing.

ACC1 Control Options
ACC7 Control Options

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