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Chapter 3: Getting Started
The Purifier Enclosures were also subjected to Biological
Containment testing, using a modified Personnel Protection Test,
as described in NSF/ANSI Standard Number 49. An aerosol
challenge of approximately 5 x 108 spores of Bacillus subtilus var
Niger were released in the enclosure and appropriate air sampling
equipment established the number of spores that escaped through
the sash opening. Each size enclosure was tested three times. All
three sizes of the enclosure were tested at 75 FPM inflow and
typically 1 or less than one spore escaped from the enclosure
during each of the tests.
The Purifier Enclosures were also subjected to an industrial
hygiene air-monitoring study to confirm the performance of the
enclosure for powders. The Purifier Enclosures demonstrated
excellent containment when used by an operator using excellent
technique and good containment when used by an operator using
marginal technique. While no enclosure can compensate for
improper technique, these tests confirm the Purifier Enclosures
provide a safe working environment.
NOTE: Face velocity profiles and smoke testing
should be performed frequently per your
organization’s quality system to ensure safe
performance.
Sealing the Filtered Enclosure to the Work Surface When the filtered enclosure has been set in place, ducted, (if
necessary), and wired, it may be sealed at the work surface to
prevent spilled materials from collecting under the walls. A bead
of silicone sealant is recommended to seal the filtered enclosure to
the work surface.
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