A cleaning process is provided for a test apparatus that has a switch, external connections and internal volumes that can come into contact with a fluid from a filter to be tested or a container to be tested. The cleaning process includes selecting one or more internal volumes to be cleaned, cleaning the selected internal volumes with a cleaning fluid by a corresponding switching of the switch, at least partially draining the cleaning fluid left in the selected internal volumes after cleaning, and flushing the selected internal volumes with a flushing fluid different from the cleaning fluid. Also provided are a computer program product for performing the cleaning process, a cleaning apparatus, and a test apparatus for testing filters and containers.