Document: 333D012G
5-18-2007
- 26 -
Replacing the HEPA Filters
When the certifier can no longer set the cabinet air flows to within
±
5
%
FPM of the nominal set point by
adjusting the speed control and/or balancing damper then it may mean the filters are loaded with particles and must be
replaced. If the filters are damaged, they will also need to be replaced.
Before any seal panels are removed, the cabinet should be decontaminated. The filters are sure to have collected
microorganisms and other potentially harmful particles generated in the work area during their lifetime, and
maintenance personnel should not allow themselves to be exposed. It should also be remembered that a specific
gaseous decontamination might work against microorganisms, but not against chemical agents. Where chemicals are
present, consult an industrial hygienist or other qualified person.
A chemically contaminated filter must be handled with caution. Clothing and/or breathing apparatus should be
used to protect personnel as necessary to reduce the hazard. It is advisable to seal the contaminated side of the filter
by taping a plastic sheet or cardboard over the face before removal. This should minimize the number of particles
shaken loose from the filter. Once removed, the filter should immediately be sealed in a chemical hazard bag and then
disposed of safely in accordance with environmental regulations.
After filter replacement has been completed, the cabinet and the room should be cleaned and decontaminated in a
manner consistent with the nature of the hazardous material. The cleaning materials, along with the protective gear
and clothing should be properly disposed.
HEPA filters are very easily damaged, and you will want to use great care in handling so as to avoid injury to the
filter media and gasket surfaces. When installing the new filters, it is a good idea to tape a piece of cardboard over the
filter media to give protection against dropped wrenches or misdirected fingers. Of course, you'll need to make sure
that the cardboard is removed before the access panels are re-installed. Inspect the filters carefully before and after
installation. A broken or damaged filter is worthless.
For detailed instructions on changing the filters, see the following two sections.
Summary of Contents for SG403A
Page 35: ...Document 333D012G 5 18 2007 34 Appendix ...
Page 38: ...Document 333D012G 5 18 2007 37 Dimensional Drawing Standard Configuration SG403A ...
Page 39: ...Document 333D012G 5 18 2007 38 Dimensional Drawing Standard Configuration SG603A ...
Page 41: ...Document 333D012G 5 18 2007 40 Interior View Exterior View Cable port plug not shown ...
Page 42: ...Document 333D012G 5 18 2007 41 Ladder Schematic SG403A ...
Page 43: ...Document 333D012G 5 18 2007 42 Ladder Schematic SG603A ...
