OC spray

Pepper spray
Heat	Peak (SR: 500,000–15,000,000)

Pepper spray (Also known as mace or capsicum spray) is a lachrymatory agent (a chemical compound that irritates the eyes to cause tears, pain, and temporary blindness) used in policing, riot control, crowd control and self-defense, including defense against dogs and bears. Its inflammatory effects cause the eyes to close, taking away vision. This temporary blindness allows officers to more easily restrain subjects and permits people using pepper spray for self-defense an opportunity to escape. Although considered a less-than-lethal agent, it has been deadly in rare cases, and concerns have been raised about a number of deaths where being pepper sprayed may have been a contributing factor.

The active ingredient in pepper spray is capsaicin, which is a chemical derived from the fruit of plants in the Capsicum genus, including chilis. Extraction of oleoresin capsicum (OC) from peppers requires capsicum to be finely ground, from which capsaicin is then extracted using an organic solvent such as ethanol. The solvent is then evaporated, and the remaining waxlike resin is the oleoresin capsicum.

An emulsifier such as propylene glycol is used to suspend OC in water, and pressurized to make it aerosol in pepper spray. High performance liquid chromatography (HPLC) is used to measure the amount of capsaicin and major capsaicinoids within pepper sprays.

Determining the strength of different manufacturers of pepper sprays can be confusing and difficult. Statements a company makes about their product strength are not regulated. A method using the capsaicin and related capsaicinoids (CRC) content of the product is unreliable as well, because there are six different types of capsaicinoids, causing different levels of irritation. Manufacturers do not state which particular type of capsaicinoids are used. Personal pepper sprays can range from a low of 0.18% to a high of 3%. Most law enforcement pepper sprays use between 1.3% and 2%. The federal government of the United States has determined that bear attack deterrent sprays must contain at least 1.0% and not more than 2% CRC. CRC does not measure the amount of OC within the formulation. Instead, CRC is the pain-producing component of the OC that produces the burning sensation.

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Wikipedia