This study examines the methods for determining the effects of temperature and relative humisity (RH) in the dimensional and mechanical properties of artists' objects, such as paintings and photographs can be modeled on the computer to correlate the magnitude of developed stresses to environmental changes. Comparing thses calculated stresses with the measured strength of the materials provides the opportunity to assess the potential risl from damage due to environmental change. Recognizing that the mechanical properties of polymeric materials are functions of the rate of the application of load, the time they are subjected to a load, the temperature and the relative humidity, it becomes a question of identifying those parameters that are the most important in determining the correct information needed for computer modeling. -- CAL