Stability studies indicated test solutions were stable for "ve days or until solutions
started to turn brown from oxidation of iodide to iodine. Adjustments of argon #ow
and gas}liquid separator drain pump rate were critical for optimum performance.
Draining the separator too rapidly resulted in reduced sensitivity because of insu$-
cient analyte hydride residence time. Foaming was not observed in the separator,
therefore, antifoaming agents were not necessary. Better precision was obtained by
using integrated absorbance rather than peak height. Contamination control was
veri"ed by analysis of method blanks. Method blank results averaged(LOD so no
blank correction was performed