Difference between revisions of "Filter Sampler"
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==Filter Baking== | ==Filter Baking== | ||
− | 1. The PSI group usually bakes their filters in the lab, and then | + | 1. The PSI group usually bakes their filters in the lab, and then ships/brings them to the field site. |
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+ | 2. Filter Baking Procedure (from Peter Zotter at PSI): A whole pack of filters (~30) is put in a quartz petri dish and put in the oven (8h at 800°C) and on the next morning after the filters have cooled down, they are wrapped in aluminum foil. So the whole procedure takes about 24h (8h prebaking and a long time cooling down) even thoug the only workstep which takes some time for me is wrapping the filters in foil (~30min up to 1h). | ||
==BEACHON== | ==BEACHON== |
Revision as of 11:23, 13 June 2011
This page is a work in progress...
Filter Baking
1. The PSI group usually bakes their filters in the lab, and then ships/brings them to the field site.
2. Filter Baking Procedure (from Peter Zotter at PSI): A whole pack of filters (~30) is put in a quartz petri dish and put in the oven (8h at 800°C) and on the next morning after the filters have cooled down, they are wrapped in aluminum foil. So the whole procedure takes about 24h (8h prebaking and a long time cooling down) even thoug the only workstep which takes some time for me is wrapping the filters in foil (~30min up to 1h).
BEACHON
- Sampling Times and Limits of Detection:
1. Chris Geron (U.S. E.P.A) measured OC levels are 0.5-2 ugC m-3 for 48-hr samples (July & August 2008)
2. Barend L. van Drooge (Molecular Tracers Analysis) needs approximately 100m3 sample. Doing the math, that means 13 1/3 hours sampling time, if we divide filters into quarters.
3. Andre Prevot (14C analysis) needs 12 hrs sampling time (Patrick Hayes has a spreadsheet from Peter Zotter with calculations). This is figured with 0.5 ug/m3 concentrations, and two (16.3 mm diameter) punches taken from a filter.
CONCLUSION: Sampling time should be a minimum of 12 hours, or 24 hours if one wants to be very cautious.