Many chemicals that are stable in their pure state become violently reactive when contaminated, heated, or combined with another chemical. Even when the reaction is intentional, as, in most chemical manufacturing, there is the potential for a runaway reaction that results in an explosion and fire. It is, therefore, important that safeguards be in place to prevent uncontrolled reactions from occurring. Failure to have these safeguards has resulted in numerous incidents. I am a founding member of the AIChE/CCPS Chemical Reactivity Roundtable which published a system for identifying potential reactive hazards and programs that can be used to control those hazards. I have also prepared a paper on the details of the programs needed to control these hazards, which is available for download here:
Explosion and fire resulting from an unexpected reaction.