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HBD Transmittance Monitor: Panametrics Vs Transmittance. HBD Working Group Meeting 5/22/2007 B. Azmoun, S.Stoll Brookhaven National Lab. Measurements since Install. Of new Panametrics H2O Head on HBD E. Notes. O2 ppm values are in reasonable agreement.
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HBD Transmittance Monitor: Panametrics Vs Transmittance HBD Working Group Meeting 5/22/2007 B. Azmoun, S.Stoll Brookhaven National Lab
Measurements since Install. Of new Panametrics H2O Head on HBD E.
Notes • O2 ppm values are in reasonable agreement. • H2O ppm values appear to be drifting apart in time (expect ppms to be ~const.). • Trans. ppm values are ~const. (with some fluctuation) • Panametrics ppm values appear to be dropping over time (longer than expected time const.), perhaps due to the accelerated aging of the H2O sensor head by CF4. • Next step is to hear back from Chemist at Panametrics who will tell us • about the physical appearance of the old H2O head after exposure to CF4 • for many months –is CF4 really eating away at the sensor? Above 10ppms of H2O • this is apparently a possibility. • Calibration drift is also a major concern (after ~ a few months) and must also be • checked by Panametrics. • Rob has ordered (or will order) a Kahn hygrometer which is more robust with • regard to slightly aggressive gases like CF4. Will do similar tests with CF4.