Drums that are swollen and distorted from over-pressurization are potentially very dangerous. They may rupture at any time without warning and release their contents. Some dangerously reactive liquids such as styrene, methyl acrylate and acrylonitrile, are also flammable liquids. They give off enough vapour at normal workplace temperatures to form flammable mixtures with air. They can be serious fire hazards at temperatures lower than those at which they would begin to polymerize or decompose.
Fires involving dangerously reactive materials can be more hazardous than normal.
The heat from the fire can lead to violent, uncontrolled chemical reactions and potentially explosive ruptures of sealed containers. Many dangerously reactive materials can also undergo dangerous reactions from direct contact with other, incompatible materials. Incompatibility hazards can be complicated. The chance of a dangerous reaction depends not just on the different combinations of chemicals involved. It also depends on the amounts of each, the surrounding conditions such as temperature, and whether the substances are enclosed in a sealed container.