There is increasing interest inmeasur-
ingwater in air at low ppm levels.
We configured anSRI 8610CGCwith
Helium IonizationDetector ( HID ) and
a 2meter Haysep-D column. Oven
temperaturewas set to 80C.
The chromatogram at right shows 1ul
of room air. We calculated that room
air contained about 21000 ppm of wa-
ter, so a 1 ul injection should contain
the same amount of water as 1ml in-
jection at 21ppm.
We then switched to a 15meter RTX
Q-plot column and injected 1ul of room
air. TheQ-plot resultswere slightly
better because of the sharper peak
shape.
Finallywe inserted a empty syringe
into the injection port and saw a
smaller water peak that we believe is
the equivalent of 6ppmwater.
Notice that the air peak is drastically
smaller.
Water analysis using the
SRI HID detector
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