NuAire LabGard NU-581-400, Operation And Maintenance Manual

Page: 63 / 107

OM0302
Rev 2/December 2020 Page 63 of 107
7.6 HEPA Filter Leak Test
In order to check filter and filter seal integrity, the HEPA filter media and seals must be directly accessible, by the measuring
instrument. There are three separate sets of HEPA filters that must be checked: Primary HEPA Prefilter, Secondary HEPA
Supply Filter and Secondary Exhaust HEPA Filter.
7.6.1 Primary HEPA Prefilters
This section will explain how to check the integrity of the HEPA prefilters that are located beneath the work
surface. In order to properly validate these HEPA filters a challenge material must be introduced (PAO, or a similar
challenge that can be detected using a particle counter) upstream of the primary filters. The scanning wand is
used to dispense the particle challenge directly at a small section of each filter in order to help isolate the position
of any leaks.
The following is needed to help check the filter integrity:
Particle counter
Particle generator
Sliding window should never be opened unless interior is known to be free of
hazardous drug residue or appropriate precautions are taken per facility
Standard Operating Procedures (SOP’S).
NOTE : Cabinet should be on and running throughout the filter replacement process.
Hazardous Drug
Using appropriate PPE, surface decontaminate or clean cabinet workzone interior including both sides of the
worktray. Remove worktray from cabinet and be sure window is at nominal work height of 8” (203mm). Remove
the stainless steel plug from the front of the base. Insert tube for particle counter and secure with low-residue tape.
Start this procedure by accessing the calibration menu, press SENSOR SETUP menu, then press the CALIBRATE
DOWNFLOW SENSOR menu, then press BLOWER DUTY CYCLE and change the speed of the motor to 850 RPM. Let
the cabinet operate at the 850 RPM level through the primary HEPA prefilter testing procedure. However once
completed
DO NOT SAVE
this RPM level but use
EXIT
to return to the main menu.
Procedure:
1. Using a stop watch and a particle counter set to .5 micron, measure the average background concentration over
60 seconds. Repeat this test 4 more times and average those readings.
2. Challenge cycle: Introduce PAO into one prefilter, One Laskin Nozzle open at 23 PSI for a period of 60 seconds
CAUTION
!
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