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Fan/Filter Unit (FFU) Challenge Port

Challenge port
  • Simplifies filter leak-test certification by easy insertion of challenge aerosol
  • Differential pressure readings help establish a filter replacement schedule
  • Polypropylene plug seals the FFU when not in use

Air filters keep your environment clean, but validating their integrity can be cumbersome and knowing when to replace them is a challenge. Room designs, applications and staffing make each cleanroom unique. Therefore, it’s important to get baseline measurements of your equipment when first installed, and then set up a schedule for regular monitoring.

Upgrade your fan/filter unit (FFU) to include a Terra-installed FFU Challenge Port that both simplifies leak testing and helps establish a filter replacement schedule. The port is 3/8"-diameter, nickel-plated brass adapter fitting with a white polypropylene plug.

Leak-testing the filter entails getting particle counts when the filter is challenged with a test substance. The challenge port simplifies this process—and saves you money when you face certification. The 3/8" port allows quick and easy insertion of a tube containing the test aerosol.

A filter replacement schedule can be established by taking a baseline measurement of the FFU pressure when first installed using a challenge port to measure differential pressure. Be sure to also record the FFU speed (high, medium, or low). Simply hook up one end of 3/8" diameter tubing to the challenge port and the other end to a Magnehelic® or other differential pressure gauge. The other channel of the gauge can remain open, registering ambient pressure. Record the reading.

challenge port with gauge

Repeat this test every six months: when the pressure differential is double that of the original reading, it’s time to order a replacement filter. Note: If you experience changes in operating conditions or fan speed, you'll need to set a new baseline.

Price includes installation on specified FFUs.

FFU Challenge Port
Cat. # Price
6601-99 $ 67

Filter Replacement Alarm System

This optional module monitors the efficiency of the HEPA filters and alerts personnel when the HEPA filters need to be replaced.  The module's Photohelic gauge connects to the nearest Fan/Filter Unit equipped with a Challenge Port (Part # 6601-99) and displays the backpressure created within the FFU.

Filter Replacement Alarm System

As the HEPA filter accumulates particles over its lifetime, pressure builds in the space between the blower and the HEPA filter.  The Photohelic gauge features two manually adjustable needles that are used to mark the original backpressure reading and the maximum acceptable level (which is typically double the backpressure reading of a new filter). When the backpressure exceeds this set limit, the LED indicator light located above the gauge will flash, notifying personnel that the room's HEPA filters should be replaced.

If a HEPA filter accumulates too many particles and becomes clogged, it can result in a loss of efficiency that can compromise the cleanroom's ISO rating.  If they are not replaced in a timely manner, severely clogged filters can destroy the motors in the Fan/Filter Units and potentially pose a fire hazard in the event of catastrophic electrical failure.

  Cat. # Price
Filter Replacement Alarm System 2625-54B-SS $ 1,140
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