HAZMAT Technician Practice Exam

What typically happens at the self-accelerating decomposition temperature?

1. Materials solidify

2. Irreversible decomposition of organic peroxides begins

3. Gas production ceases

4. Solid materials dissolve into liquids

The correct answer is: Irreversible decomposition of organic peroxides begins

The self-accelerating decomposition temperature (SADT) is a critical temperature for materials such as organic peroxides, where an increase in temperature leads to an increase in the rate of decomposition. This phenomenon is significant because once a material reaches its SADT, the decomposition reactions become self-sustaining and can escalate rapidly, potentially leading to safety hazards such as fires or explosions. When organic peroxides approach or exceed their SADT, the stored energy from the decomposition reactions can cause irreversible breakdown. The reactions are marked by the release of heat and gas, producing byproducts that can further drive the reaction and make it uncontrollable. Therefore, recognizing the temperature at which this irreversible decomposition begins is crucial for managing safety and preventing incidents involving hazardous materials. The other options do not accurately reflect the behavior of materials at their SADT. Solidification, gas production cessation, or dissolution into liquids do not occur at this temperature; rather, the opposite is true as the material undergoes significant change due to the rapid and exothermic nature of the decomposition process.