Stability Evaluation of Ambient Concentrations of Sulfur Dioxide,Nitric Oxide,and Nitrogen Dioxide Contained in Compressed Gas Cylinders,

摘要

Compressed gas samples of sub-part per million concentrations of sulfur dioxide,nitric oxide,and nitrogen dioxide were evaluated for long and short term stability. Except for several stainless steel tanks,the samples were contained in aluminum cylinders. A degree of stability was achieved over the short term,however,all of the samples were considered unstable over the term of the evaluations. Utilization of ambient level compressed gas samples may be considered where relative stability is required for no more than two or three months.