Pepper spray is made up of an active ingredient called OC (Oleoresin
Capsicum) and other inert ingredients. They can be water or oil based.
The best formula being oil based as oil based products do not have the
problem of separation. Separation is where the final blend will not
stay blended and the oil (OC) will separate from the water base. This
is very similar to putting oil in water. The oil will want to rise to
the top. All OC products that the Pepper Spray Store sells are
non-toxic and non-flammable. The effects of the pepper spray last
between 20 and 90 minutes, giving the user plenty of time to escape
their terrifying situation. Pepper spray units can be fired multiple
times and can have a range of 8 to 20 feet, depending on the particular
model you purchase.



The newest defensive spray agent, Oleoresin Capsicum, is
a derivative of hot cayenne peppers. OC is an inflammatory agent and
unlike tear gas it is effective on those under the influence of drugs
and alcohol. When the OC contacts the mucous membranes (eyes, nose,
throat, and lungs), symptoms will appear instantly. The capillaries of
the eyes will immediately dilate, causing temporary blindness.
Inflammation of the breathing tube tissues will cause difficulty in
breathing; however the victim will still be able to breathe. Pepper
spray will not deteriorate with age and will not cause lasting
aftereffects, however the short-term effects are quite effective.
Some consumers think that when it comes to pepper defense spray, the
higher the percentage, the better the pepper spray. However, this is
not true. The percentage of OC does not correlate to the spray’s level
of intensity. An effective spray allows the victim to disable the
attacker and escape or take control of the situation.



OC is effective against all attackers; even attackers
who cannot feel normal levels of pain (psychotics, drug abusers,
alcohol abusers) will be affected by pepper spray. Pepper spray is also
the best deterrent against attacking wild or vicious animals.



The actual term OC (oleoresin capsicum) refers to
chili peppers, and is a horticultural term. Jalapenos, chiletpin,
cayenne, and habaneros are all chili peppers. Although they look quite
different, and can taste quite different, they all contain an alkaloid
called capsaicin. Capsaicin is tasteless and odorless. It is so
powerful that even when it is immersed in water, the heat from it can
be detected. Studies show that humans can detect even one part per ten
million of this powerful alkaloid.



In 1912, Wilbur Scoville, a pharmacologist, developed
the standard for measuring the power of capsaicin. The Scoville
Organoleptic Test was used to determine the temperature of peppers.
Scoville conducted his research by measuring the ground pepper into a
mixture of sugar, water, and alcohol. He then took the mixture to a
panel of tasters who then gave the mixture a grade between zero and
5,000,000 with a majority needed to assign a proper value. This is
now referred to as an SHU or Scoville Heat Unit.



Today the method of measuring the power of capsaicin
is much more sophisticated. High Pressure Liquid Chromatography or
HPLC is a computerized method that is now used to determine the Total
Capsaicinoid % and SHU. It is a significantly more accurate method of
testing the heat of OC.

http://www.pepper-spray-store.com/relatedinfo/whatis.shtml

Pepper spray, known as Oleoresin
Capsicum (OC), is a chemical weapon designed to irritate the eyes and
inflict pain; it also affects the respiratory system should it be inhaled.
Its primary ingredient comes from capsicum, the pepper
family of plants. Their fruit varies in hotness, from the no-tingle bell pepper
to the eyes-burning chili pepper. Capsaicin is the chemical responsible for the
spicy heat of the pepper; this heat is measured using the Scoville scale. Pure
capsaicin has a Scoville heat unit of 15–16 million; law enforcement grade pepper spray has a Scoville
heat unit of 5-5.3 million. The Pimento,
Peperoncini and Banana pepper peppers have a Scoville heat unit of 100-900. Tabasco and Cayenne
peppers are 30,000-50,000; Tabasco
sauce (original) is 2,500-5,000 heat units.
As an agent of pain, pepper spray was adopted by the
U.S. Postal Service in the 1980s as a dog
repellant (pdf).

http://themoderatevoice.com/129350/pepper-spray-incidents-backfire-in-california-and-oregon-when-is-pepper-spray-excessive-force/