Which of the following chemical warfare agents is NOT considered a casualty agent?

The classification of chemical warfare agents typically divides them into categories based on their effects on humans, particularly in relation to military operations. Casualty agents are those that can cause significant harm or incapacitation, leading to a loss of personnel effectiveness in a combat situation.

Vomiting agents, while causing distress and incapacitation, are primarily classified as incapacitating agents rather than casualty agents. They induce nausea and vomiting, which can disrupt operations but are not necessarily lethal or directly harmful in the way that blood, blister, or nerve agents are.

Blister agents cause severe skin and respiratory damage, blood agents disrupt oxygen transport in the body, and nerve agents attack the nervous system, often resulting in quick and lethal consequences. Therefore, vomit agents serve a different purpose in the context of chemical warfare; they are more about incapacitation rather than causing death or long-term injury, which is why this option is not considered a casualty agent.