Which category refers to the duration of the chemical agent's effects?

• A. Persistency
• B. Onset effects
• C. Route of entry
• D. Physical state

Answer: (A)

Focus on how long a chemical agent keeps acting after release. Persistency describes how long the agent remains active in the environment and continues to produce effects, which directly maps to the duration of those effects. Onset effects is about the time between exposure and when symptoms first appear, not how long they last. Route of entry concerns how the agent enters the body, affecting absorption and speed of action, while physical state (gas, liquid, solid) influences dispersion and handling. So the category that best captures the duration of effects is persistency.