This report provides the results of the initial development of scaling laws for use in developing cost effective experimental measurements of a passenger rail car heat release rate (HRR) history as well as modeling approaches for predicting passenger rail car HRR. Scaling laws were successfully developed to predict the fire dynamics and material burning behavior in pre-flashover and fully-developed fires. In addition, a finite element (FE) model for window failure was developed to support the design of small scale windows. Fire Dynamics Simulator (FDS) was used to provide detailed predictions of the fire HRR history using a pyrolysis model for material burning. In addition, a simplified model was created for use by designers and operators. Future work is recommended to generate data to further validate the scaling laws and models.