Reaction hazards represent significant challenges in the chemical industry, driven by their intrinsic complexity, which often impedes the accurate identification and quantification of runaway reaction consequences. This article presents an advanced scenario-based strategy for reaction hazard analysis, empowering industries to proactively identify potential risks and predict outcomes of reactive chemical processes. By leveraging the synergistic capabilities of adiabatic calorimetry and dynamic simulation technologies, this approach enables precise characterization and quantification of chemical reaction hazards. The methodology supports the design of inherently safer processes, reducing the likelihood of catastrophic events such as fires, explosions, and toxic releases. A case study on styrene polymerization illustrates the practical application and effectiveness of the proposed strategy.