The Space Station Projects Office (SSPO) at NASA's Ames Research Center (ARC) is responsible for operational plans for plant and animal research in the Life Sciences Research Facility (LSRF) aboard the Space Station. As a planning database, the SSPO uses scientists' descriptions of experiment operations, configured into scenarios for typical 90-day missions. Both research tasks and tasks involving specimen care and housekeeping are included. Four of these scenarios were used to test a computer program named OpSim, developed by the ARC Space Human Factors Office specifically to simulate Space Station operations. The tasks for each scenario were set up for inputting to OpSim, simulations were executed and program output was analyzed. Some scenarios were simulated more than once, at different levels of crew time availability and of laboratory automation. The test showed that OpSim gives an informative picture of mission operations, and that it responds appropriately to changes in variables such as crew availability and automation. OpSim should become widely used to model Space Station operations and develop realistic plans.