 called CF, formerly known as EA1779. It can be disseminated as an aerosol or as a fine dust cloud, and it has a swift and pronounced effect on men. So much so that the United States Army Chemical Warfare Laboratories are investigating its possible use as an incapacity agent. By our definition, an incapacity agent is one that destroys or greatly reduces a person's ability to perform his duty. It has a large margin of safety between the effect details and the lethal dose, and it permits complete recovery. When CF is used, exposure to an amount as low as one part per million produces almost immediate effects. These usually continue from 5 to 10 minutes, and in some situations, they last for 20 or 25 minutes. Because CF has the characteristics of an incapacity agent, it has been the subject of study and experimentation. Here is the story of CF. Under the terms of the tripartite standardization agreement, information about CF was exchanged between the United States and Great Britain which used CF for riot control. In the Chemical Warfare Laboratories, a program was instituted to determine the feasibility of using CF in a tactical situation. Criteria for the study were based upon experiments then being conducted in a dynamic aerosol exposure chamber, a structure designed to study effects of proposed compounds. Typical is the experience of these army volunteers who enter the chamber knowing they would be subjected to an aerosol of a new compound but not knowing what the effects would be. The dose selected for this first test was at the minimal level based on British findings that CF is effective in extremely low concentrations. Careful control of these chamber tests resulted in a dose of only two parts per minute. Even so, the effects were apparent almost at once. Although told to remain in the chamber as long as they could, in just 27 seconds the volunteers left the chamber. They experienced typical symptoms including eye irritation, lacrimation, sneezing, coughing, and labored breathing. With preliminary data from these chamber tests in hand, field trials were scheduled under stimulated tactical situations. In the first trial, troops from several scattered army units were exposed to the compound. They were instructed to put on protective masks when they thought it was necessary. Experimental grenades containing one quarter pound of agent combined with a burning mixture were in place for static firing to simulate preparatory fires of an attacking force. These grenades have an emission time of 20 to 25 seconds. Upon firing the grenades, what appears to be a dense cloud of agent was formed, but only one fifth of the cloud was actually CS. Highest concentrations achieved were two to three ten-thousandths of one percent in air. As the agent cloud reached the defensive position, some of the men succeeded in putting on their masks, but others were completely incapable of doing so because the effects of the agent were so rapid and severe. The obscuring effect might be minimized by disseminating the agent from other types of munitions rather than from burning grenades. Masked observer was assigned to each volunteer to record his reactions and to assist him in case he was overcome by the agent. Effects of the agent, even in extremely low concentrations, are so rapid and so acutely painful that a man becomes obsessed with an overpowering desire to remove his mask and escape from the cloud. Even then, some men collapse on the ground or wander around in a state of helplessness. In this test, every one of the volunteers abandoned his position. The agent produced severe irritation of the eyes, nose, throat, and lungs. Among the symptoms were the same convulsive coughing, heavy-lavered breathing, and searing chest pains experienced by the wind tunnel volunteers. Conspicuous elevation occurred. The eyes lacrimated and closed involuntarily, and they could be opened only with great difficulty. In severe cases, nausea and vomiting occurred. Frustrating as these effects are, the exposed individual recovers in from 5 to 15 minutes after he gets into an atmosphere of fresh air. The feeling of exhaustion and weakness may persist for a few hours after the worst of the effects have worn off. Although effective in very low concentrations, exposure to heavy doses of the agent does not result in permanent injury to the individual. The rapidity with which this incapacitating agent can temporarily prostrate a man demonstrates its effectiveness for riot control and gives rise to serious consideration that it might have potential uses in combat operations. The potential was tested in another field trial using trained troops from the 3rd Battalion's 3rd Armored Cavalry Regiment in a simulated tactical situation. The same type of burning grenades was functioned in the path of the attackers. The concentration of agent was the same, 2 to 3, 10,000 of 1%. One man ran through the first cloud before he felt the effects of CS. However, before passing through the second cloud, he had lost his impetus. Effects varied depending upon the dosage received by each man. The attacking group of this well-trained army unit was demoralized by CS. Some of the men lost their helmets, rifles, and masks in their confusion. Others reported they had put on protective masks, but the constriction in their chests prevented them from clearing the masks properly. They were forced to remove the masks in order to breathe. In about 10 minutes, the squad had recovered completely. However, none of those affected volunteered to repeat the test. There are several methods of effective dissemination made possible by adapting existing material. The burning type grenade already has been demonstrated. A new kind of bursting grenade made of plastic material so that the fragments are non-lethal also can be affected in dispersing a dust cloud of CS, which has a pronounced effect on the eyes. Good coverage with particulates of CS also can be obtained by use of a special gun attached to the standard flamethrower. Large area dispersion by helicopter is possible with the mounted disperser, as well as with a truck mounted standard gasoline powered disperser. Other studies are developing the feasibility of adapting the standard smoke generator. Using the exhaust of military vehicles to disseminate this compound and producing quick coverage with multiple grenade launchers. Yes, is a potent agent with a definite place in our arsenal of munitions.