In this study, a series of experiments were carried out to measure temporal stability of trimethylamine (TMA) in two different bag sampler types (polyvinyl fluoride bag (PVF) and polyester aluminum bag (PEA)) as a function of storage time. To this end, temporal variability of TMA was measured using its standard gas samples up to 4 days. For the purpose of comparison, storability of TMA was tested between PVF and PEA. To this end, standard gas samples were prepared at two concentration levels of 1 and 10 ppm. The results of this study indicate that the reduction of TMA levels generally increased with the extension of the storage time. Although both bag types showed moderate losses of TMA, differences between bag types (PVF and PEA) were likely to be less significant than those of concentration levels.