Data from the Hazardous Substances Emergency Events Surveillance system was used to identify factors associated with the severity of injuries of victims (an ordinal outcome variable) harmed in acute chemical release events in the manufacturing industry. We used proportional odds models to account for the order of severity in the outcome, with the general estimation equation. There were 659 events involving 2826 victims. More severe injuries were associated with explosion (adjusted OR aOR = 6.45), multiple chemicals (aOR = 1.75), multiple chemical categories (aOR = 1.70), the chemical group acids (aOR = 1.6), multiple injuries to an individual (aOR = 1.38–1.56) (ranges represent several models), confinement within a structure in a fixed facility (aOR = 1.76–1.90), and being located in the midwest region (aOR = 1.76–1.90). The summer was less likely than all other seasons to be associated with more severe outcome. The results provide information beneficial for preventive activities.