BIOPAN (Biological Pan) is a multi-purpose exposure and re-entry facility for small sized experiments in the field of exo-biology and radio-biology. It has been developed by Kayser-Threde under ESA contract. Development was completed by a qualification flight on FOTON 8 in 1992. Subsequently three operational missions were performed in 1994 (FOTON 9), 1997 (FOTON 11) and 1999 (FOTON 12). All missions were fully successful and delivered comprehensive data on orbital environment and re-entry impact.The paper summarizes the environmental data measured during four missions and compares the measurements with the predictions performed during the development of BIOPAN. It concludes on the assumptions made for the flight predictions and the learning process with regard to improved predictions. The paper describes the applied methods to control the energy budget and reports on the proven function of the self-protection mechanism (emergency closing). In orbit temperatures for exposed and shielded experiments as well as re-entry temperature profiles for scientific hardware and structure underneath the heatshield are presented.