Abstract: The present techniques, including methods and systems, relate to obtaining or producing a concentrated gas sample from a non-concentrated gas sample with a trap that is not inline with (or indirectly connected to) a chromatographic method, and injecting a controlled volume of the concentrated gas sample in a sample loop including a valve or similar chromatographic component through a sample line. The method includes preparing the concentrated gas sample from the non-concentrated gas sample with a trap; controlling a temperature of an internal volume of the trap to reach a release temperature; injecting the concentrated gas sample in a sample line towards a sample loop, the sample line and sample loop being at a sub-atmospheric pressure; and operating the sample loop to release the concentrated gas sample contained in the sample loop in a chromatographic method, wherein the trap is not inline with the chromatographic method.