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Chapter 6: Maintaining Your Filtered Enclosure
9. Carefully fold and roll the new bag in four-inch pleats and
push the bag into the access port. Reinstall the retaining
strap and bungee cords. Turn the enclosure ON to draw a
vacuum on the bag. Reinstall the front panel.
Figure 6-1
Bag-In-Bag-Out HEPA Filter Changing Procedure Diagram &
Filter Leak Test Diagram
HEPA Filter Leak Test
Purpose
After installing the new HEPA filter, the HEPA filter should be
leak checked. This test is performed to determine the integrity of
the HEPA filter, the filter housing, and the filter mounting frames.
Leak testing is to be done by a qualified technician with calibrated
equipment. Remove the top perforated exhaust cover by using a
Phillips screwdriver to unfasten the (2) screws used to secure (2)
clips. See Figure 6-1. The filter passes the leak test at .01% or
better. Reference Leak Testing and Photometer scanning from the
Institute of Environmental Services (IES-RP-CC001.3)
HEPA