Bipolar commercial-off-the-shelf (COTS) circuits are increasingly used in spacemissions due to the low cost per part. In space environments these devices are exposed to ionizing radiation that degrades their performance. Testing to evaluate the performance of these devices is a costly and lengthy process. As such methods that can help predict a COTS part’s performance help alleviate these downsides. A modeling software for predicting total ionizing dose (TID), enhanced low dose rate sensitivity (ELDRS), and hydrogen gas on bipolar parts is introduced and expanded upon. The model is then developed in several key ways that expand it’s features and usability in this field. A physics based methodology of simulating interface traps (NIT) to expand the previously experimental only database is detailed. This new methodology is also compared to experimental data and used to establish a link between hydrogen concentration in the oxide and packaged hydrogen gas. Links are established between Technology Computer Aided Design (TCAD), circuit simulation, and experimental data. These links are then used to establish a better foundation for the model. New methodologies are added to the modeling software so that it is possible to simulate transient based characteristics like slew rate.