Abstract: An improved chromatographic method for measuring impurities in a gas sample that allows extraction of a peak of impurity masked by the sample background. An impurity peak is extracted from the sample background and put in a second sample loop and the second sample loop volume is injected into a second separation column. A “slice” is taken from the sample background to fill the second sample loop and the “slice”, whose width is preferably substantially equal to the impurities peak width, is injected into the second separation column. Another embodiment allows concentration of a predetermined impurity, thereby providing an improved precision on the results. The chromatographic method provides an improved measure of argon in oxygen, oxygen in argon and oxygen in hydrogen.

Abstract: The present invention provides an improved chromatographic system and an improved chromatographic method for measuring impurities in a gas sample that advantageously allow to extract a peak of impurity masked by the sample background. The method extracts an impurities peak from the sample background and put it in a second sample loop. Then, this second sample loop volume is injected into a second separation column. In fact, the system takes a “slice” from the sample background and fills the second sample loop with it. Then, the “slice”, whose width is advantageously substantially equal to the impurities peak width, is injected in the second separation column. In a further preferred embodiment, the method also advantageously allows to concentrate a predetermined impurity, thereby providing an improved precision on the results. The chromatographic method advantageously provides an improved measure of argon in oxygen, oxygen in argon and oxygen in hydrogen.

Abstract: A fluid sampling system and a method thereof are provided. The fluid sampling system is provided with a plurality of sampling channels, each of the sampling channels comprising a sampling line having an inlet, a regulated outlet, and first and second calibrated flow orifices connected in series between the inlet and outlet. Each of the sampling channels also comprises a controllable derivation line connected between the first and second orifices, for deviating fluid from the sampling line. The fluid sampling system is also provided with a connecting line for connecting together the outlets of the sampling lines. The connecting line has a main regulated outlet for providing a fluid sample.