What type of sensation does CS (Orthochlorbenzalmalonitrile) primarily cause?

CS (Orthochlorobenzalmalonitrile), commonly known as tear gas, primarily causes extreme burning of the eyes. This compound is specifically designed to irritate mucous membranes, leading to an intense sensation that can result in tearing, redness, and a burning feeling. The eyes are particularly sensitive to CS gas, making this effect prominent and one of the primary indicators of exposure.

When CS is deployed, it acts quickly, often leading to uncontrollable tearing and a strong urge to close the eyes, which can momentarily incapacitate an individual. While it can also provoke other reactions such as nasal irritation and skin burning, the extreme eye reaction is the hallmark effect of this chemical agent, distinguishing it from other sensations that might be caused by different irritants. Understanding this foundational effect is crucial for crowd management scenarios, particularly in assessing the immediate impacts of CS exposure on a crowd.