A pair of undergraduates in a chemistry class loaded a pressure vessel (a “Parr bomb”) with reactants and placed the vessel in a furnace, leaving the reaction to run for the night.

Several hours later, during an evening class in the same lab, an unanticipated reaction occurred in the vessel. This raised the pressure beyond the established safe operating limit for the experiment and burst the vessel’s safety rupture disc. The class heard a loud bang followed by a strong odor described as “microwaved broccoli.”

The instructor evacuated the lab. Because procedures were not clear, a delay followed before anyone contacted Security and Health, Safety & Environment. Once the authorities were notified, the laboratory was inspected for damage, and ventilation was increased to remove the odor (which had spread throughout the floor).

Learn more about this incident in Incident pressure relief UTL Apr2014.