FEMA Standardized Awareness Practice Test 2025 – Your Comprehensive All-in-One Guide to Exam Success!

Choking agents are a category of chemical warfare agents that primarily target the respiratory system, causing severe damage to the lungs. This class of agents includes substances such as chlorine and phosgene, which, when inhaled, lead to symptoms such as coughing, choking, and the potential for pulmonary edema. The mechanism of choking agents involves irritation of the respiratory tract and the disruption of gas exchange in the lungs, which can result in suffocation if exposure is intense or prolonged.

In contrast, blister agents cause severe skin and mucosal blistering and are not specifically lung-targeting agents. Nerve agents interfere with the nervous system, affecting muscle control and autonomic functions rather than primarily impacting the lungs. Blood agents disrupt the body's ability to use oxygen at the cellular level and can affect the entire system but do not specifically target the respiratory system like choking agents do. Thus, choking agents uniquely represent the effects on the lungs, making them the correct identification in this context.