Decontamination, Determination of when to replace hepa filters, How to install a new hepa filter – Labconco Class I Enclosure Models 3980423 User Manual
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Chapter 6: Maintaining Your Filtered Enclosure
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Decontamination
When used in conjunction with biohazards, the Purifier Class I Enclosure and
Purifier HEPA Filtered Enclosure should be decontaminated with formaldehyde
gas before:
maintenance work in contaminated areas
HEPA filter changes
moving the cabinet to a new location
changing research programs
after a gross spill of biohazardous material
The procedures for performing a gaseous decontamination are thoroughly outlined
in the U.S. Department of Health, Education and Welfare booklet entitled
Formaldehyde Decontamination of Laminar Flow Biological Safety Cabinets,
available from NIH, Division of Safety, Bethesda, MD 20892, call 301-496-2801,
or from Labconco Corporation.
Determination of When to Replace HEPA
Filters
The HEPA filters in the filtered enclosures gradually accumulate airborne
particulate matter and powders from the enclosure and room. The rate of
accumulation will depend upon the cleanliness of the room air, the amount of time
the enclosure is operating, and the nature of work being done in the enclosure. In
typical installations and usage, the HEPA filters will last two to five years before
requiring replacement. Replace HEPA filters when face velocity drops below the
recommended 75-105 fpm velocity, and the speed control is adjusted to full speed.
Replace HEPA filters if it fails the HEPA Filter Leak Test in Chapter 6.
How to Install a New HEPA Filter
NOTE: The enclosure must be properly decontaminated before servicing the
HEPA filter. Only a qualified certifier should service the HEPA filter.
After the HEPA filter is replaced, the enclosure MUST be certified. See
Figure 6-1.
1. Unplug the enclosure.
2. Remove the front panel by loosening the two screws that secure it, and then
remove the filter access cover.
3. Using a 9/16" deep socket, loosen the filter clamp bolts located on top.
Refer to Figures 4-1 and 4-2.
4. With the clamp bolts loosened, the HEPA filter-clamping frame should be
clear of filter. Carefully pull the filter straight out of the enclosure and
discard properly.
5. With the filter removed, inspect the clamping frame and the frame of the
cabinet for damage.