Be sure to open the "Pressure Building" valve on the argon Dewar to maintain enough pressure. I have had runs stop because the pressure dropped below the minimum requirement causing the instrument to shut down. And, of course, check to make sure the Dewar has enough argon for how many hours the run will take. May seem obvious but most of us have made this mistake before.
William Mindak, Chemist
Center for Food Safety & Applied Nutrition
US Food & Drug Administration
5100 Paint Branch Pky
College Park, MD 20740
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From: PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's). [mailto:[log in to unmask]] On Behalf Of H Muhanna
Sent: Friday, December 03, 2010 11:47 PM
To: [log in to unmask]
Subject: Re: overnight runs with Agilent 7500a
Besides the software command that does the trick, you should be aware of
special concerns with night runs.
Make sure everything is in top condition , like sample tubing. If it is worn
out for example, it can leak during the night when no one is around, and you
come next day with a long list of useless data.
Also, make sure to provide enough wash solution for the whole run.
Basically, take an inventory of everything that is consumed during a day run
and see if it is automatically provided at night.
Also, take into account that a working day is 8 hours long, but a "working
night " ( 5pm - 8 am ) is 15 hours long.
Hasan H. Al-Muhanna
Center for Environment & Water
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