Met One Instruments LVS-100, Руководство пользователя

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MicroVol-1100 User manual 1.6 Installation
A log-book sample page can be found at the back of this manual.
2.6.3 Post Collection Equilibration
Carefully remove the filter elements from their holders and check them for
defects that may have occurred during sampling. The sample should be
reasonably even across the element. Localised dark spots could indicate
pinhole leaks. Filter holder support screens will produce a pattern on the filter.
If this is unacceptable due to the type of analysis being performed requiring a
steady filter loading, an optional woven wire screen support is available.
Place the filter element on its numbered Petri dish and cover the top of the
dish with a paper towel.
Record the relative humidity, temperature, date and time of the post collection
equilibration. The equilibration temperature and relative humidity should be as
close as possible to the initial equilibration conditions. Once again, each filter
should be allowed to equilibrate for at least 24 hours.
2.6.4 Final weighing
Use the same microbalance that was used in the initial weighing. Before
weighing the filters, turn the microbalance on for 1 hour to allow them to
stabilise.
Weigh each filter at least twice and record the average final mass of each
filter, Wf. Always check the zero reading of the microbalance between each
reading.
Immediately after weighing, place each filter into a Petri dish with lid, sample
side up, and record the time and dates that the sample was taken.
Record the relative humidity, temperature, date and time of the final weighing.
Refer to the Calculation section for method of determining mass
concentrations.
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