Process safety decision making in chemical engineering practice has a strong ethical and moral component. While effective process safety decision making can be taught, it is not solely a technical topic, and includes complex behavioral elements that classroom-based instruction finds difficult to capture. To capture the complexity of this decision making, we have developed a digital immersive environment, Contents Under Pressure (CUP), that includes both technical and behavioral elements. This immersion allows participants to explore realistic process safety decision points in a safe environment. To determine the effect of CUP on moral reasoning, a retrospective study of two cohorts was conducted. The first cohort (n = 109) received traditional process safety instruction, and the second cohort (n = 181) had CUP included as part of their instruction. Pre- and post-assessment of participant process safety reasoning was achieved via the Engineering Process Safety Reasoning Instrument (EPSRI), also developed by the authors. Analysis of the data suggests that exposure to CUP has a distinct and statistically significant impact on process safety reasoning as compared to the comparison cohort.