Vacutainers are used by the Bureau of Mines and the Mining Enforcement and Safety Adminstration (MESA) for sampling mine air and products of combustion. Tests were conducted on both 10-ml and 30-ml sizes to study shelf life stability during storage, pretreatment of stoppers, and handling of a wider range of compounds. A chamber was constructed to provide convenient, efficient evacuation of the vacutainers shortly prior to use. Fixed gases and c1-c5 hydrocarbons could be stored for 1 week or more after sampling. Where decreases occurred (co2 and c3-c5 hydrocarbons), they were predictable as a function of storage time. An unexplained phenomenon, slow accumulation of CO in evacuated vacutainers, occurred after a few weeks of storage. The levels were low and time dependent. Attempts to eliminate this behavior by pretreating the stoppers were unsuccessful.