Labconco Protector Work Stations 3930021 - Manual (Page 56)

Chapter 6: Maintaining Your Enclosure
Product Service 1-800-522-7658 52
Time - For applications that have very consistent inlet concentrations and
operating time, “Time” can be used to anticipate saturation or TWA levels based
on prior experience. However, this does not replace the need for sampling.
Consult Labconco technical specialist for an estimate of carbon filter life based on
chemical usage. Detector tubes, or analytical instrumentation should always be
used to determine concentrations in the carbon filter. It is recommended that the
carbon filters be checked with detector tubes or other means at intervals of 20% of
the total estimated filter life. The exception to the 20% recommendation is
formaldehyde and any carcinogen or suspected carcinogen. These more hazardous
chemicals must be checked at least every 10% of the total estimated time.
Analytical Instrumentation - This is the most accurate means of measuring
concentrations of any chemical. It is the method of choice when no detector tubes
are available or the tubes are not sensitive enough to measure at the TWA
concentration for the chemical. This method is also to be used to determine
saturation when the chemical concentration is below the measurement range of
detector tubes.
Carbon Filter Replacement Procedure – See Figure 6-10 for Carbon Filter
Replacement.
1. The carbon filters are replaced by first removing the two knobs, which hold
the rear perforated baffle in place. Then carefully lower the perforated
baffle, which is heavy because of the carbon filters.
2. Carefully remove both carbon filters.
3. If using formaldehyde, the formaldehyde filter is always placed
downstream of the organic vapor filter. (The formaldehyde filter is on top
of the organic vapor filter in the loading position. The same applies with
ammonia and formaldehyde. No specific placement is required with
organic vapor and ammonia.
4. Re-install the new carbon filters with the gasket up or on the downstream
side.
5. Pivot the perforated baffle up and replace and tighten the knobs.