Which control measure is most effective in preventing hazards when a process is exothermic?

• A. Adequate cooling and proper venting
• B. Increasing agitation and mixing speed
• C. Adding more reactants
• D. Isolating the reactor from the environment

Answer: (A)

In exothermic processes, heat removal is critical to safety because the hazard comes from heat building up faster than it can be removed, which can lead to runaway reactions or overpressure. Adequate cooling and proper venting directly address this by removing excess heat to keep the temperature under control and by providing a safe outlet for any generated gases or pressure. Cooling slows or halts the rate of heat production and reduces the risk of thermal runaway, while venting prevents dangerous pressure buildup as gases evolve. Other options don’t prevent the underlying issue: increasing agitation might help transfer heat but can also accelerate the reaction if heat isn’t adequately removed; adding more reactants adds more exothermic energy; isolating the reactor from the environment reduces heat loss and can worsen the temperature rise. That’s why cooling and venting is the most effective control.