Abstract: A closed positive pressure evaporation system for evaporating samples in preparation for analysis comprising a plurality of sample vials where each sample vial has associated therewith an inlet and an outlet. An chamber is provided having a heat source and a holder for positioning and holding the sample vials with reference to the heat source. A distribution manifold is connected via tubing to the inlet of each sample vial for distributing purified inert gas, such as Nitrogen, to each sample vial held by the holder in the chamber. A collection manifold is connected via tubing to the outlet means of each sample vial for collecting purified inert gas, such as Nitrogen, and gases from each sample vial connected to the distribution manifold. The chamber, distribution manifold and collection manifold coacting to expose a sample in each sample vial to only purified inert gas, such as Nitrogen, during the evaporation of the sample.