The biological mechanism by which riot-control agents work has not been well studied or documented compared to the other types of chemical agents. Generally, riot-control agents cause pain, tearing, and conjunctivitis in the eyes, which can be accompanied by spasms of the muscles around the eyes. A burning sensation occurs in the nose and respiratory tract. This is followed by sneezing and a large volume of nasal discharge. The chest may feel tight, and there may be a shortness of breath accompanied by coughing and secretions from the bronchial tubes when inhaled. Contact with the skin produces tingling, a burning feeling, and present along with a high concentration of high temperature and humidity are present along with a high concentration of agent, blisters may occur within 8-12 h, which are similar to those produced by vesicants. Blisters have been reported by firefighters resulting from exposure when entering buildings where law enforcement personnel have discharged CS. Death, although rare, may occur from riot-control agents when exposure occurs in confined areas for an extended period of time. However, there are no reported deaths from open-air use