A metering apparatus for a reprocessing device for reprocessing surgical instruments. The metering apparatus including: a metering chamber for accommodating a reprocessing fluid, wherein the metering chamber comprises: an inlet for letting the reprocessing fluid into the metering chamber； and an outlet for letting out the reprocessing fluid introduced into the metering chamber, wherein the inlet and the outlet are dimensioned such that a flow velocity of the reprocessing fluid from the outlet while the reprocessing fluid is being let out of the metering chamber is greater than a flow velocity of the reprocessing fluid into the inlet while the reprocessing fluid is being introduced into the metering chamber.
