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Replacing the NPD Bead
Instruction Guide
Agilent Technologies
Replacing the NPD Bead
7890A and 6890 Gas Chromatographs
This instruction guide reviews the procedure for installing a
bead on a nitrogen- phosphorus detector (NPD). Before
following this procedure, refer to the safety information on the
inside front cover and in your GC user information.
Parts list
• 1 NPD bead assembly (ceramic or Blos)
• Cap for the bead
• Test chromatogram
NOTE
If you used Blos beads before 2008, you may notice that the current bead
has a slightly different shape and color. This is normal.
NPD Bead Replacement.book Page 3 Monday, October 13, 2008 2:32 PM