TEAR GAS
CS or 2-chlorobenzalmalononitrile (chemical formula: C₁₀H₅ClN₂) is a substance that is used as a riot control agent and is usually claimed to be non-lethal by the forces who use it. CS was discovered by two Americans, Ben Carson and Roger Staughton in 1928, the first letters of the scientists' surname giving us the name of the substance, 'CS'.

In common parlance CS is referred to as 'CS gas' or 'Tear gas', however this description is incorrect because 2-chlorobenzalmalononitrile is a solid at room temperature, not a gas.

It is worth noting that many types of tear gas have been produced with effects ranging from mild tearing of the eyes to immediate vomiting and prostration. CS has become the most popular due to its strong effect and lack of toxicity in comparison with other similar chemical agents. The effect of CS on a person will depend on whether it is packaged as a solution, or if it is an aerosol; the size of solution droplets and the size of the CS particulates after evaporation, are factors determining its effect on the human body.

Well... I had my first taste of the stuff today. We were covering a hostage situation and after hours of fruitless negotiating the SWAT team deployed the GAS. They shot over 60 rounds of it. I got a good whiff before donning my gas mask. It was like rubbing a freshly cut habanero pepper in your eye and nose.